[Federal Register Volume 63, Number 151 (Thursday, August 6, 1998)]
[Rules and Regulations]
[Pages 42110-42189]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-19929]
[[Page 42109]]
_______________________________________________________________________
Part II
Environmental Protection Agency
_______________________________________________________________________
40 CFR Parts 148, 261, 266, etc.
Hazardous Waste Management System; Identification and Listing of
Hazardous Waste; et al.; Final Rule and Proposed Rule
Federal Register / Vol. 63, No. 151 / Thursday, August 6, 1998 /
Rules and Regulations
[[Page 42110]]
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 148, 261, 266, 268, 271, and 302
[SWH-FRL-6122-7]
RIN 2050-AD88
Hazardous Waste Management System; Identification and Listing of
Hazardous Waste; Petroleum Refining Process Wastes; Land Disposal
Restrictions for Newly Identified Wastes; And CERCLA Hazardous
Substance Designation and Reportable Quantities
AGENCY: Environmental Protection Agency.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The Environmental Protection Agency (EPA) is amending the
regulations for hazardous waste management under the Resource
Conservation and Recovery Act (RCRA) to reduce hazards to human health
and the environment from wastes generated from petroleum refining. EPA
is listing as hazardous four wastes generated during petroleum refining
and is issuing a decision not to list ten other petroleum refining
wastes.
This action is taken under the authority of RCRA 3001(b)(1), which
authorizes EPA to list wastes as hazardous, and 3001(e)(2), which
directs EPA to make a decision whether to list as hazardous the various
petroleum refining wastes. The effect of listing these four wastes will
be to subject them to stringent management and treatment standards
under RCRA and to emergency notification requirements for releases of
hazardous substances to the environment. These notifications are
required under the Comprehensive Environmental Response, Compensation,
and Liability Act (CERCLA or Superfund) and the Emergency Planning and
Community Right to Know Act (EPCRA). EPA is also issuing Reportable
Quantity (RQ) adjustments for these notifications.
This action also makes certain changes to the RCRA regulations to
promote the environmentally sound recycling of oil-bearing residuals.
Specifically, the Agency is excluding certain recycled secondary
materials from the definition of solid waste. These materials include
oil-bearing residuals from petroleum refineries when they are inserted
into the petroleum refining process, oil from associated petrochemical
facilities inserted into the petroleum refining process, and spent
caustic from liquid treating operations when used as a feedstock to
make certain chemical products. This rule also clarifies an existing
exclusion for recovered oil from certain petroleum industry sources.
Finally, EPA is applying universal treatment standards (UTS) under
the Land Disposal Restrictions program to the petroleum refining wastes
listed in this rulemaking. The listed wastes must be treated to meet
these treatment standards for specific constituents prior to land
disposal.
EFFECTIVE DATES: This final rule is effective February 8, 1999, except
for the amendments to Secs. 261.3(c)(2)(ii)(B), 261.4(a),
261.6(a)(3)(iv)(C) and 261.100(b)(3) and the removal of
Sec. 261.6(a)(3)(v) which are effective August 6, 1998.
ADDRESSES: Supporting materials are available for viewing in the RCRA
Information Center (RIC), located at Crystal Gateway I, First Floor,
1235 Jefferson Davis Highway, Arlington, VA. The Docket Identification
Number is F-98-PRLF-FFFFF. The RIC is open from 9 a.m. to 4 p.m.,
Monday through Friday, excluding federal holidays. To review docket
materials, it is recommended that the public make an appointment by
calling 703 603-9230. The public may copy a maximum of 100 pages from
any regulatory docket at no charge. Additional copies cost $0.15/page.
The index and some supporting materials are available electronically.
See the beginning of the Supplementary Information section for
information on accessing them.
FOR FURTHER INFORMATION CONTACT: The RCRA/Superfund Hotline, toll-free,
at (800) 424-9346 or at (703) 920-9810. The TDD Hotline number is (800)
553-7672 (toll-free) or (703) 486-3323 in the Washington, DC.,
metropolitan area.
For technical information on the RCRA hazardous waste listings,
contact Maximo (Max) Diaz, Jr., or Robert Kayser, Office of Solid Waste
(5304W), U.S. Environmental Protection Agency, 1235 Jefferson Davis
Highway, Arlington, VA, (703) 308-0439. [E-mail addresses and telephone
numbers: [email protected], (703) 308-0439;
[email protected], (703) 308-7304.] For information related
to the exclusions from the definition of solid waste, contact Ross
Elliott at the same address. [[email protected]; (703) 308-
8748.]
For technical information on the CERCLA aspects of this rule,
contact: Ms. Elizabeth Zeller, Office of Emergency and Remedial
Response (5204G), U.S. Environmental Protection Agency, 401 M Street,
SW, Washington, D.C., 20460, (703) 603-8744.
SUPPLEMENTARY INFORMATION: The index and the supporting materials are
available on the Internet. Follow these instructions to access the
information electronically:
www:http://www.epa.gov/epaoswer/osw/hazwaste.htm#id
FTP: ftp.epa.gov
Login: anonymous
Password: your Internet address
Files are located in /pub/epaoswer
The contents of the preamble to this final rule are listed in the
following outline:
I. Affected Entities
II. Legal Authority and Background
A. Listing Decisions
B. Definition of Solid Waste and Exclusions
III. Summary of Proposal and Notice of Data Availability
A. Proposed Exclusions
1. Exclusion of Oil-Bearing Hazardous Secondary Materials
Inserted into Petroleum Refining, Including Petroleum Coking
2. Recovered Oil From Associated Petrochemical Facilities
3. Use of Spent Caustics as Feedstock
B. Proposed Listing Decisions
1. Summary of Proposed Decisions
2. Summary of Proposed Risk Assessment Approach
C. Notice of Data Availability
IV. Changes to the Proposed Rule
A. Definition of Solid Waste Exclusions
1. Exclusion of Oil-Bearing Hazardous Secondary Materials
Inserted into Petroleum Refining, Including Petroleum Coking
2. Recovered Oil From Associated Petrochemical Facilities
3. Use of Spent Caustic as Feedstock
B. Listing Determinations
C. Other Exemptions
1. Headworks Exemption
2. Exemption for Catalyst Support
3. Third Party Recycling of Spent Petroleum Catalysts
V. Response to Comments and Rationale for Final Rule
A. Proposed Modifications to the Definition of Solid Waste
1. Exclusion of Oil-Bearing Hazardous Secondary Materials
Inserted into Petroleum Refining, Including Petroleum Coking
2. Recovered Oil From Associated Petrochemical Facilities
B. Modeling Approaches and Risk Assessment
1. Sampling and Analysis of Refinery Wastes
2. Waste Management Assumptions
3. Codisposal of Wastes
4. Impact of Hazardous Characteristic Regulations
5. Other General Risk Issues
6. Specific Groundwater Modeling Issues
7. Specific Nongroundwater Modeling Issues
[[Page 42111]]
C. Residual-Specific Comments
1. Crude Oil Storage Tank Sediment
2. Clarified Slurry Oil Sediment
3. Catalyst From Hydrotreating and Hydrorefining
4. Catalyst From Sulfuric Acid Alkylation
5. Spent Caustic From Liquid Treating
6. Off-Specification Product and Fines From Thermal Processes
7. Catalyst and Fines From Catalytic Cracking
8. HF Alkylation Sludge
9. Sludge From Sulfur Complex and Hydrogen Sulfide Removal
Facilities
10. Catalyst From Sulfur Complex and Hydrogen Sulfide Removal
Facilities
11. Unleaded Gasoline Storage Tank Sediment
12. Catalyst From Reforming
13. Sludge From Sulfuric Acid Alkylation
D. Headworks Exemption
1. Application to Listed Catalysts
2. Clarification of Scope
3. Comments Opposing the Exemption
E. Third Party Recycling of Spent Petroleum Catalysts
VI. Land Disposal Restrictions
A. Treatment Standards for Newly Identified Wastes
B. Response to Comments
1. Constituents of Concern
2. Sulfides
3. Underlying Hazardous Constituents
4. High Temperature Metals Recovery
5. Vanadium
6. Revisions to Proposed Standards
C. Capacity Determination for Newly Identified Wastes
1. Introduction
2. Capacity Analysis Results Summary
VII. Compliance and Implementation
A. State Authority
1. Applicability of Rules in Authorized States
2. Effect on State Authorizations
B. Effective Date
C. Section 3010 Notification
D. Generators and Transporters
E. Facilities Subject to RCRA Permit Requirements
1. Facilities Newly Subject to RCRA Permit
2. Existing Interim Status Facilities
3. Permitted Facilities
4. Units
5. Closure
F. Landfill Leachate
VIII. CERCLA Designation and Reportable Quantities
A. Reporting Requirements
B. Standard and Alternative RQ Adjustment Methodology
C. Basis for RQ Adjustments in Final Rule
D. Response to Comments
IX. Executive Order 12866
X. Economic Analysis
A. Compliance Costs for Listings Including LDR Impacts and the
Exclusion for Oil-Bearing Hazardous Secondary Materials
1. Universe of Petroleum Refineries and Waste Volumes
2. Methodology for Estimating Industry Economic Impact and
Incremental Compliance Cost
3. Potential Remedial Action Costs Within the Refining Industry
4. Summary of Compliance Cost Results
B. Details of Industry Economic Impact
XI. Regulatory Flexibility Act
XII. Submission to Congress and the General Accounting Office
XIII. Unfunded Mandates
XIV. Paperwork Reduction Act
XV. National Technology Transfer and Advancement Act
XVI. Executive Order 13045--Protection of Children from
Environmental Health Risks and Safety Risks
I. Affected Entities
Entities potentially affected by this action are those which handle
either the waste streams being added to EPA's list of hazardous wastes
under RCRA and to the CERCLA list, or entities which need to respond to
releases. Affected entities include:
------------------------------------------------------------------------
Category Affected entities
------------------------------------------------------------------------
Industry..................... Generators of the following listed
wastes, or entities that treat, store,
transport, or dispose of these wastes.
K169--Crude oil storage tank sediment
from petroleum refining operations.
K170--Clarified slurry oil storage tank
sediment and/or in-line filter/
separation solids from petroleum
refining operations.
K171--Spent hydrotreating catalyst from
petroleum refining operations, including
guard beds used to desulfurize feeds to
other catalytic units (this listing does
not include inert support media).
K172--Spent hydrorefining catalyst from
petroleum refining operations, including
guard beds used to desulfurize feeds to
other catalytic units (this listing does
not include inert support media).
State, Local, Tribal Govt.... State and local emergency planning
entities.
Federal Govt................. National Response Center, and any Federal
Agency that handles the listed waste or
chemical.
------------------------------------------------------------------------
This table is not intended to be exhaustive, but rather provides a
guide for readers regarding entities likely to be affected by this
action. This table lists those entities of which EPA now is aware that
potentially could be affected by this action. Other entities not listed
in the table also could be affected. To determine whether your facility
is regulated by this action, you should examine 40 CFR Parts 260 and
261 carefully in concert with the amended rules found at the end of
this Federal Register notice. If you have questions regarding the
applicability of this action to a particular entity, consult the person
listed in the preceding FOR FURTHER INFORMATION CONTACT section.
II. Legal Authority and Background
These regulations are being promulgated under the authority of
sections 2002(a) and 3001(a), (b) and (e)(2), 3004 (g) and (m) of the
Solid Waste Disposal Act (commonly referred to as RCRA), as amended, 42
U.S.C. 6912(a), and 6921(b) and (e)(2), and section 102(a) of CERCLA,
42 U.S.C. 9602(a).
A. Listing Decisions
Section 3001(a) of RCRA requires EPA to promulgate criteria for
identifying characteristics of hazardous wastes and for listing
hazardous wastes. Section 3001(b) authorizes EPA to promulgate
regulations, based on these criteria, identifying and listing hazardous
wastes. Section 3001(e)(2) of RCRA requires EPA to determine whether to
list, as hazardous, wastes generated by specific industries and
production processes, including petroleum refining wastes. Hazardous
waste, for purposes of this rule, is defined at section 1004(5)(B) of
RCRA as solid waste which may pose a substantial present or potential
hazard to human health or the environment when improperly managed.
Hazardous wastes are subject to management and treatment
requirements of RCRA Subtitle C, which establishes stringent federal
requirements, including the need to obtain facility operating permits
for persons who generate, transport, treat, store, or dispose of such
waste. Solid wastes which are not hazardous may be disposed of at
facilities which are overseen by state and local governments. These are
the so-called RCRA subtitle D facilities, which generally impose less
stringent requirements on management of wastes.
[[Page 42112]]
EPA's regulations at 40 CFR 261.20 provide that hazardous wastes
may be classified as ``characteristic'' wastes if they have the
properties described at 40 CFR 261.21 through 261.24, which would cause
them to be classified as having the characteristics of ignitability,
corrosivity, reactivity, or toxicity. Characteristic wastes are
identified by sampling a waste, or using appropriate company records
concerning the nature of the waste, to determine whether a waste has
the relevant properties. There is no regulatory requirement to conduct
sampling, but persons managing materials that are found to be
characteristic hazardous wastes are subject to enforcement actions
under RCRA.
Criteria for listing hazardous wastes are found at 40 CFR
261.11(a)(3), which provides that wastes may be listed as hazardous if
they contain hazardous constituents identified in appendix VIII of 40
CFR part 261 and the Agency concludes, after considering eleven factors
enumerated in Sec. 261.11(a)(3), that the waste is capable of posing a
substantial present or potential hazard to human health or the
environment when improperly managed. A substance is listed in appendix
VIII if it has been shown in scientific studies to have toxic effects
on life forms.
EPA's regulations at 40 CFR 261.31 through 261.33 contain the
various hazardous wastes the Agency has listed from time to time.
Section 261.31 lists wastes generated from non-specific sources, known
as ``F-wastes,'' and Sec. 261.32 lists hazardous wastes generated from
specific sources, known as ``K-wastes.'' Pursuant to the requirement of
RCRA section 3001(e)(2) to list refinery wastes, EPA has previously
listed various petroleum refinery wastes designated as F037, F038, and
K048 through K052. Section 261.33 lists as hazardous discarded
commercial chemical products and other materials that become hazardous
wastes, known as ``P-wastes'' or ``U-wastes,'' when they are discarded
or intended to be discarded.
Therefore, newly listed wastes in this rule will be added to the K-
waste list. Once listed, wastes must be managed as RCRA Subtitle C
hazardous wastes. No testing of waste samples is required as for
characteristic hazardous wastes.
On June 12, 1997, EPA entered into a proposed amended consent
decree in a lawsuit filed by the Environmental Defense Fund (EDF)--EDF
v. Browner, Civ. No. 89-0598 (D.D.C.). The consent decree sets out a
series of deadlines for promulgating RCRA rules. Paragraph 1.k. of the
proposed amended consent decree obligated EPA to promulgate a final
listing determination on or before May 29, 1998 (EPA and EDF have since
agreed to extend this date to June 29, 1998), for 14 additional
petroleum refining process residuals. Today, EPA is issuing final
listing determinations for these residuals (hereafter, ``listing
residuals'') in accordance with the proposed consent decree's deadline.
The consent decree also identified another 15 petroleum refining
residuals for which EPA agreed to conduct a study (hereafter, ``study
residuals''). EPA published the study in 1996. (See Study of Selected
Petroleum Refining Residuals-Industry Study, August 1996; EPA530-R-96-
018.)
All hazardous wastes listed under RCRA and codified in 40 CFR
261.31 through 261.33, as well as any solid waste that exhibits one or
more of the characteristics of a RCRA hazardous waste, described in 40
CFR 261.20 through 261.24, are also hazardous substances under CERCLA,
as provided in CERCLA section 101(14)(C). CERCLA hazardous substances
are listed in Table 302.4 at 40 CFR 302.4 along with their reportable
quantities (RQs). Today's rule also establishes RQs for the newly
listed wastes.
Today's listing determination follows the elements of EPA's
hazardous waste listing policy presented in the dyes and pigments
listing determination proposal (59 FR 66072, December 22, 1994). A
description of how elements of EPA's listing policy were applied in
today's listing determination is found in Section III.F.2., ``Risk
Analysis,'' of the preamble for the proposed rule. Section V.C of this
preamble discusses EPA's responses to comments and final decisions as
they relate to the various elements of the listing policy and their
applicability to this rule.
B. Definition of Solid Waste and Exclusions
The jurisdictional boundaries of RCRA are established primarily by
the definition of solid waste. When hazardous sludges, by-products, and
spent materials (often referred to as a group as ``secondary
materials'') are recycled, a question exists as to whether such
materials are ``solid wastes'' and so potentially within EPA's subtitle
C jurisdiction. The regulatory definition of solid waste, found at 40
CFR 261.2, answers these questions, since only materials which meet
this definition are even potentially subject to the subtitle C
regulatory program set out at 40 CFR Parts 262-268. Secondary materials
may be excluded from the definition of solid waste, and therefore from
regulation under this regulatory program, if they are recycled in
certain ways. The current definition of solid waste at 40 CFR 261.2
excludes secondary materials from the definition of solid waste that
are used directly (i.e., without reclamation) as ingredients in
manufacturing processes to make new products, used directly as
effective substitutes for commercial products, or returned directly to
the original process from which they are generated as a substitute for
raw material feedstock. (See 40 CFR 261.2(e)(1)). As discussed in the
January 4, 1985, rulemaking that promulgated this regulatory framework,
these are activities which, as a general matter, resemble ongoing
manufacturing operations more than conventional waste management and so
are more appropriately classified as not involving solid wastes. (See
50 FR at 637-640).
However, these exclusions do not apply to materials that are either
contained in, or used to produce, fuels and, therefore, do not
generally apply to secondary materials recycled as part of the
petroleum refining process (see 40 CFR 261.2(e)(2)(ii)). Petroleum
industry representatives have long argued that oil-bearing secondary
materials used as ingredients in a petroleum refining process to make
fuel should be excluded from the definition of solid waste under
RCRA.1
---------------------------------------------------------------------------
\1\ See the proposed rule (specifically 60 FR 57752 to 57753)
for a detailed discussion on the background to these regulatory
issues.
---------------------------------------------------------------------------
While these exclusions from the definition of solid waste are not
available to hazardous secondary materials generated by, and used as
ingredients in, the petroleum refining industry, these hazardous
secondary materials, or the fuels produced from them, may be exempt
from all regulatory requirements under 40 CFR 261.6(a)(3)(iii)-(v).
These exemptions from regulatory requirements, however, did not resolve
the jurisdictional debate involving the continued processing of
hazardous secondary materials into fuels.
Regarding this debate ,the plain reading of the statute has been
supplemented by case law providing parameters within which to determine
whether secondary materials being recycled are or are not solid wastes.
In its decision in American Mining Congress v. EPA, (824 F. 2d 1177
(D.C. Cir. 1987) (AMC I)), the D.C. Circuit Court held that EPA's rules
defining the statutory term ``solid waste'' (RCRA Section 1004(27))
exceeded the Agency's statutory authority to the extent that the rules
asserted jurisdiction over ``materials that are recycled and reused in
an ongoing manufacturing or industrial process''
[[Page 42113]]
(Id. at 1186 (emphasis original)). The Court held that ``[b]ecause
these materials have not yet become part of the waste disposal
problem'' (Id.), they are not yet ``discarded'' within the meaning of
Section 1004(27) and so cannot be considered to be ``solid wastes.''
On January 8, 1988, EPA responded to the AMC I decision by
proposing to exclude, from the regulatory definition of solid waste,
oil-bearing petroleum residuals that are returned for further refining
``as part of one continuous and ongoing process.'' (see 53 FR FR 525,
Jan. 8, 1988). More specifically, EPA proposed to exclude oil-bearing
residues from the refining process when those residues are generated
on-site and reinserted on-site into the petroleum refining process
(including the coker), provided that the residues were not
speculatively accumulated or stored in a manner involving land
placement.
Subsequent decisions have established that the decision in AMC I is
relatively narrow. In particular, courts have rejected the argument
that ``potential reuse of a material prevents the Agency from
classifying it as `discarded' '' (see, American Mining Congress v. EPA,
907 F. 2d 1179, 1186 (D.C. Cir. 1990) (AMC II)). The proper test as to
when, as a matter of law, the Agency is foreclosed from classifying a
material as a solid waste is when a material is ``destined for
immediate reuse in another phase of the industry's ongoing production
process'' and that has ``not yet become part of the waste disposal
problem'' (Id. at 1186 (emphasis original)). EPA retains considerable
discretion in ascertaining how to apply this standard.
For example, secondary materials generated by one industry and sent
to another industry for reclamation could be classified as solid wastes
(although EPA retains some discretion as to whether to make that
determination) (see, American Petroleum Inst. v. EPA, 906 F. 2d 726,
740-41 (D.C. Cir. 1990); Ilco v. EPA, 996 F. 2d 1126 (11th Cir. (1993);
Owen Electric Steel v. Browner, 37 F. 3d 146 (4th Cir. 1994)).
Similarly, secondary materials generated onsite, stored in surface
impoundments, and reclaimed within the process which generated them
could also be classified as solid wastes (see AMC II). EPA must
normally justify determinations that a secondary material being
recycled is not a solid waste by showing how the determination is
consistent with RCRA's objective to ``establish a cradle-to-grave
regulatory structure for the safe handling of hazardous wastes'' (see
API, 906 F. 2d at 741).
On July 28, 1994, EPA finalized parts of the January 8, 1988,
proposal pertaining to petroleum refining industry operations. As noted
in that final rule, post-AMC I decisions make clear that the statute
affords EPA great latitude to set the jurisdictional parameters of
RCRA. As a consequence, the July 28, 1994, final rule excluded a more
limited set of materials and imposed greater restrictions on where the
materials can be inserted within the petroleum refining process, than
what was proposed on January 8, 1988. Specifically, in its January 1988
proposal, EPA did not distinguish between recovered oil (i.e., oil
reclaimed from secondary materials, such as wastewater, generated from
normal petroleum refining, exploration and production, and
transportation practices) and oil-bearing hazardous sludges, nor did it
distinguish between the petroleum coker and other petroleum process
units in defining the scope of the proposed petroleum refining
exclusion. In the July 28, 1994, final rule, EPA limited the exclusion
to recovered oil that is inserted into the petroleum refining process
prior to distillation and catalytic cracking. Thus, it did not apply to
recovered oil reinserted into the petroleum coker (see 40 CFR
261.4(a)(12) and 59 FR at 38541-38542, July 28, 1994). In at least one
respect, the July 28, 1994, final rule was somewhat broader than what
was proposed. The final exclusion applied to materials generated from
petroleum industry sources other than refineries, while the January 8,
1988, rule proposed to exclude only oil-bearing materials generated at
a refinery and reinserted into that refinery's refining process.
After promulgation of the July 28, 1994, final rule excluding
certain recovered oil, the EPA published a direct final rule on March
26, 1996, to correct an inadvertent error in the regulatory text of the
exclusion (see 61 FR 13103). Specifically, the direct final rule
amended the words describing the point of insertion for recovered oil
into the petroleum refining process (i.e., ``prior to crude
distillation or catalytic cracking'') that was a condition of the
exclusion. The original intent was to exclude recovered oil inserted
into the refining process where the process removes at least some
contaminants (which does not include cokers). After promulgating the
exclusion, the Agency learned that delineating where recovered oil
could or could not be inserted (and be excluded) using the words
``prior to crude distillation or catalytic cracking'' was
unintentionally restrictive, i.e., those operations were common
examples but there were other refinery units where contaminants were
removed as well. In addition to the amended regulatory text, the Agency
also clarified that the recovered oil exclusion applied to oil
recovered from shared wastewater treatment systems at petroleum
refineries co-located with petrochemical facilities (see 61 FR 13104).
Because the Agency received no adverse comment as of April 9, 1996, on
the amended regulatory text, the direct final rule became effective on
May 28, 1996.
Today's final rule, which deals specifically with petroleum
residuals, gives EPA the opportunity to address some larger,
longstanding issues involving where the boundaries of RCRA should be
drawn regarding jurisdiction over oil-bearing hazardous secondary
materials which are generated by, and recycled within, the petroleum
industry. Therefore, in addition to addressing specific regulatory
issues that may arise as a result of a decision to list an individual
petroleum waste stream, the Agency is issuing more comprehensive
revisions to the RCRA regulations relating to regulatory jurisdiction
over these materials when this type of intra-industry recycling occurs.
III. Summary of Proposal and Notice of Data Availability
A. Proposed Exclusions
The proposed rule discussed the applicability of the definition of
solid waste to the waste streams being evaluated for listing, but also
related to a broader class of petroleum wastes. This is discussed
briefly below.
1. Exclusion of Oil-Bearing Hazardous Secondary Materials Inserted Into
Petroleum Refining, Including Petroleum Coking
In the November 20, 1995, proposal, the Agency proposed to exclude
oil-bearing secondary materials generated within the petroleum industry
that are inserted into the petroleum coker (see 60 FR at 57754-57755).
Generally, these secondary materials are generated as either residues
of various refining processes or wastewater treatment systems which
collect process waters (and oil) from the entire facility. (Note that
these secondary materials, primarily wastewater treatment sludges, do
not meet the definition of ``recovered oil'' because the contained oil
is a small percentage of the total.) Secondary materials, such as
wastewater treatment sludges, that contain a high percentage of oil are
often processed to recover the oil for further refining (e.g., when
there
[[Page 42114]]
is free oil). However, the typical oil recovery process (e.g.,
centrifugation) cannot recover all of the oil from these secondary
materials, leaving a not insignificant amount of oil in the secondary
materials that can only be recovered thermally.
In conventional petroleum coking operations (also known as
``delayed coking''), heavy oil-bearing feedstocks, typically bottoms
from crude oil distillation or vacuum distillation (also referred to as
``resids,'' representing the heaviest oil fraction of the crude oil
feedstock) are placed into a coke drum. This material is then heated to
high temperatures, thermally breaking or ``cracking'' the long-chain
hydrocarbon molecules found in heavy oil feedstock into short-and
middle-chain oil fractions that are then recovered, condensed, and sent
for further refining into high-value fuel products. The remains of the
heavy oil-bearing feedstock (which is primarily carbon and some
inorganic contaminants) forms the coke product, typically used as a
fuel.
The last step of the conventional coking operation involves the
injection of water to quench the coke product. Water is injected in the
base of the coke drum and works its way up through the coke product,
cooling the coke as it goes. This quenching also serves to remove light
ends entrained within the coke product, similar to steam stripping.
(The light ends recovered during the quenching process are likewise
condensed and further refined into high-value fuel products.) Once cool
enough, the coke product is typically removed from the coke drum using
high pressure water drilling. For the purposes of this preamble
discussion, it is important to distinguish between the two aspects of
the coking operation. The first aspect, referred to in this preamble as
``conventional coking,'' involves the recovery of light-end
hydrocarbons from the resids feedstock and produces the coke product.
The second aspect, referred to here as the ``quenching process,''
involves the injection of water into the high-temperature coke to cool
it down after the conventional coking process.
In the preamble discussion in the November 20, 1995, proposal, the
Agency presented its determination that the petroleum coker is an
integral part of the petroleum refinery process, with recovered middle-
and light-end hydrocarbons as its primary product and petroleum coke as
a co-product. Based on the information on hand comparing the
composition of oil-bearing hazardous secondary materials to typical
feedstocks to the coker, and the fact that the coke produced using oil-
bearing hazardous secondary materials demonstrated no significant
increase in hazardous metals concentrations, the Agency proposed to
exclude such oil-bearing secondary materials when used in the
production of petroleum coke. EPA believed this exclusion was further
justified because the hazardous secondary materials are managed in a
manner to prevent release, commensurate with management of nonhazardous
oil-bearing feedstocks. (See 60 FR 57754-57755). In addition, the
proposed exclusion was conditioned on there being no speculative
accumulation or land placement (thus ensuring that the secondary
materials would not be stored such that they could become part of the
waste disposal problem), and that the coke product itself not exhibit a
characteristic of hazardous waste, which, along with existing product
specifications, would serve to ensure that the quality of the coke
product would not degrade through the use of hazardous secondary
materials such that it would become part of the waste disposal problem.
At the time of the proposal, the Agency did not distinguish between
oil-bearing hazardous secondary materials used in either of the two
aspects of the coking operations, i.e., in the conventional coking
process (where secondary materials would be used as feedstocks) or
during the quenching process (where secondary materials are mixed with
water and injected into the coke during the quenching process). While
the Agency was aware that oil-bearing hazardous secondary materials
were being used in the quenching process at some refineries, the
primary focus and intent of EPA's proposed exclusion was for secondary
materials used as feedstock in the conventional coking process, with a
secondary consideration being whether these secondary materials
legitimately could be used in the quenching process. As the Agency
learned through comments received, the hazardous secondary materials in
question (i.e., listed hazardous wastes generated by petroleum
refineries) are rarely, if indeed ever, used as feedstock along with
the resids. EPA, therefore, has since focused its attention on the role
of oil-bearing hazardous secondary materials in the quenching process,
maintaining the key consideration that the exclusion is only intended
for oil-bearing hazardous secondary materials used in a manner
consistent with the main production purpose of the coking process,
i.e., the recovery of light-end hydrocarbons for further refining and
the production of a marketable coke product.
2. Recovered Oil From Associated Petrochemical Facilities
In the November 20, 1995 proposal, EPA proposed to add an exclusion
at 40 CFR 261.4(a)(13) for recovered oil 2 that is generated
by certain organic chemical industry facilities and inserted into
petroleum refining processes provided that certain conditions are met
(i.e., the petrochemical recovered oil is not stored in a manner
involving placement on the land, or accumulated speculatively before
being recycled) (see 60 FR at 57755. The proposed exclusion only
applied to petrochemical recovered oil from organic chemical
manufacturing facilities that were within the SIC code 2869, and was
further limited to situations where the petrochemical and petroleum
refinery facilities were either co-located, or under common ownership
(co-owned). (Id).
---------------------------------------------------------------------------
\2\ Recovered oil, as defined within the context the exclusion
from the definition of solid waste promulgated in the July 28, 1994,
final rule, includes materials that are primarily oil and that are
recovered from any phase of petroleum exploration, production,
refining, and transportation related thereto. Oil recovered from
petrochemical facilities associated with petroleum refineries,
whether from shared wastewater treatment systems at co-located
facilities, or from other ``dry'' streams recovered from
petrochemical process units, are referred to here as ``petrochemical
recovered oil.''
---------------------------------------------------------------------------
As described in the proposed rule, the recovered oil exclusion that
was promulgated in the July 28, 1994, final rule did not apply to oil
from organic chemical industry operations except in cases where
petrochemical and petroleum refining operations share a common
wastewater treatment system. In these instances, because a portion of
the oil recovered during wastewater treatment and returned to petroleum
refining originates from organic chemical manufacturing, some industry
representatives questioned whether a ``petroleum industry'' exclusion
would apply. However, because of the predominance of petroleum refining
wastewaters in the shared wastewater treatment systems, and the degree
of integration between these facilities, the Agency believed that it
was appropriate to apply the July 28, 1994, recovered oil exclusion to
the oil recovered from shared petrochemical and petroleum refining
wastewater treatment systems. (see 61 FR at 13104). The EPA
subsequently became aware that some petrochemical facilities recover
oil from their process streams in a manner distinct from wastewater
treatment operations and send this material (so-called ``dry''
hydrocarbon streams) to
[[Page 42115]]
petroleum refineries for insertion into the refining process. In some
cases these hydrocarbon materials might or might not be viewed as solid
wastes when returned to petroleum refining operations as feedstocks in
producing the normal slate of refinery produced fuels. After
promulgation of the July 28, 1994, rule, EPA received information from
the chemical manufacturing industry indicating that these ``dry''
hydrocarbon streams recovered from their operations are comparable to
oil recovered from petroleum refining operations, i.e., are chemically
comparable to the recovered oil already excluded from being a solid
waste. As explained in more detail in the proposed rule, the exclusion
for petrochemical recovered oil was therefore based upon two specific
arguments raised by both the chemical manufacturing and petroleum
refining industries. First, knowledge of the composition of these
petrochemical recovered oil streams is very important because of the
potential for adverse impacts on both refinery operations (e.g.,
equipment corrosion, catalyst fouling) and product quality (e.g.,
introduction of contaminants that degrade motor fuels) if these streams
contain constituents not typically encountered in normal refinery
feedstocks. Second, analytical data the Agency received prior to
proposal supported industry's premise that recovered oil from
petrochemical operations is similar in composition to that from
petroleum refining, and is therefore suitable for insertion into the
petroleum refining process.3 EPA based the proposed
exclusion for petrochemical recovered oil on a very limited set of data
from integrated petrochemical and petroleum refineries that were either
co-located or co-owned, and EPA believed that this was a typical
arrangement for the return of these hydrocarbon streams to petroleum
refineries (see 60 FR at 57756). In the proposal, EPA solicited
additional data which could support broadening the exclusion to
recovered oil from other SIC codes representing other types of
associated chemical manufacture (e.g., plastics and resins, synthetic
rubber, cyclic crude and intermediate producers). (Id).
---------------------------------------------------------------------------
\3\ September 13, 1995, letter to Becky Daiss (EPA Office of
Solid Waste) from Michael W. Steinberg (Morgan, Lewis & Bockius).
---------------------------------------------------------------------------
3. Use of Spent Caustics as Feedstock
EPA proposed an exclusion from the definition of solid waste that
would clarify that spent liquid treating caustics from petroleum
refineries used as feedstock in the manufacture of naphthenic and
cresylic acid products are not solid wastes. EPA believed that, when
used in this manner, spent caustic is a valuable commercial feedstock
that is used in the manufacture of commercial chemical products.
Therefore, EPA proposed to add a new Sec. 261.4(a)(14) to exclude spent
caustic when used in this manner.
B. Proposed Listing Decisions
1. Summary of Proposed Decisions
EPA evaluated 14 wastes (the consent decree ``listing residuals'')
in the petroleum refining industry, proposing to list 3 of these wastes
as hazardous and not the other 11 wastes. Further general background
for this rule is provided in the preamble to the proposed rule at 60 FR
57748-57749. As a result of numerous comments on the proposed rule, EPA
conducted additional analyses for these wastes, resulting in the
Agency's publishing a Notice of Data Availability (NODA) on April 8,
1997 (62 FR 16747). This Section summarizes the issues raised in the
proposed rule and the following Section describes the NODA.
The Agency proposed to list as hazardous the following three
wastes:
K170--Clarified slurry oil storage tank sediment and/or in-line filter/
separation solids from petroleum refining operations.
K171--Spent hydrotreating catalysts from petroleum refining operations.
(This listing does not include ceramic support media.)
K172--Spent hydrorefining catalysts from petroleum refining operations.
(This listing does not include ceramic support media.)
The Agency proposed not to list as hazardous the following eleven
residual categories:
Crude oil storage tank sediment
Unleaded gasoline storage tank sediment
Off-specification product and fines from thermal processes
Catalyst from reforming
Catalyst from sulfuric acid alkylation
Sludge from sulfuric acid alkylation
Hydrofluoric acid alkylation sludge
Spent caustic from liquid treating
Catalyst and fines from catalytic cracking
Catalyst from sulfur complex and hydrogen sulfide removal
facilities
Sludge from sulfur complex and hydrogen sulfide removal
facilities.
EPA also noted that its decision not to list crude oil storage tank
sediment was a close call, and that the Agency may choose to list this
waste as K169, depending on further evaluation of the data and
comments.
The proposed listing determinations were based on the Agency's
evaluations at the time as to whether the wastes met the criteria in 40
CFR 261.11(a) for listing wastes as hazardous. EPA assessed and
considered the factors contained in these criteria primarily by
incorporating them as elements in a risk assessment. A detailed summary
of the risk assessment methodology is found in the preamble to the
proposed rule, Section III.F, ``Description of Health and Risk
Assessments'' (60 FR 57756-57762). EPA's view at the time of proposal,
the applicability of the risk assessment to particular waste streams,
and the proposed reasoning for the listing decisions are found in
Section III.G., ``Waste-Specific Listing Determination Rationales'' (60
FR at 57762-57776).
EPA also proposed a number of exemptions for the wastes proposed
for listing, described below.
Headworks Exemption
In the proposal, EPA noted that some refineries manage the wastes
EPA proposed for listing in their wastewater treatment system, while
and others may scour residual sludge of the wastes proposed for listing
during vessel cleaning or tank washing into the refinery wastewater
treatment system. A consequence of listing these wastes as hazardous
would be to cause all wastewaters and wastewater treatment sludges to
be derived from those wastes.
The Agency noted in the proposal that, provided the residuals
derived from the wastes proposed for listing are discharged to the oil
recovery sewer system, the residuals carried into the wastewater system
would be removed during primary treatment as sludges or other wastes
that are already regulated hazardous wastes (e.g., K048, K051, F037, or
F038). Accordingly, the Agency proposed not to include these
wastewaters in its listing determinations and to modify an existing
regulation at 40 CFR 261.3(a)(2)(iv) to provide that these wastewaters
would not be considered hazardous wastes. This exemption, known as the
``headworks exemption,'' was discussed in the preamble for the proposed
rule at 60 FR 57750 and 57781. The proposal noted that the exemption
would apply to wastewaters containing clarified slurry Oil (CSO)
sediment and, if EPA decided to list crude oil storage tank sediment in
the final rule, this waste as well.
Exemption for Catalyst Support
Upon removal from catalyst beds and/or during catalyst regeneration
or reclamation, spent catalysts are separated from the support media
that
[[Page 42116]]
are used in the catalytic reactors to optimize mixing and flow within
the reactor beds. The Agency proposed an exclusion from RCRA regulation
(under 40 CFR 261.3(c)(2)(ii)) for these support media because the
support media are generally inert ceramics, separate from the catalyst,
and commonly managed separately.
Third Party Recycling of Spent Petroleum Catalysts
Spent hydrotreating and hydrorefining catalysts, two of the wastes
proposed for listing (as K171 and K172, respectively), are frequently
regenerated for reuse or reclaimed off-site to recover nonprecious
metals (e.g., nickel, molybdenum, cobalt, and vanadium) and other
compounds sold as products (i.e., aluminum sulfate derived from the
alumina substrate material).
In the proposed rule preamble in Section III.J.1., ``Third Party
Regeneration/Reclamation of Spent Petroleum Catalysts'' (60 FR 57781),
EPA proposed to clarify the regulatory status of units that regenerate
or reclaim these catalysts. The proposal would have clarified that
these units are specifically excluded from regulation as industrial
furnaces under EPA's boiler and industrial furnace (BIF) rules at 40
CFR Part 266, Subpart H. The proposed clarification was based on a
number of factors, including EPA's view that the units differed from
those considered for the BIF rule and the Agency's general view that it
did not want to impose an unnecessary regulatory burden that may serve
to discourage environmentally safe recycling of spent petroleum
catalysts.
The proposal also stated, however, that EPA had not fully evaluated
the prevalence and adequacy of existing emission controls and the
potential for uncontrolled emissions of toxic organic compounds, toxic
metals, and particulate matter from spent hydrotreating and
hydrorefining catalysts. Accordingly, the Agency stated that if it
found that emissions from these units pose a threat to human health and
the environment, it would reconsider the proposed clarification of the
BIF rule and even could determine that the rule should, instead, be
amended to specifically apply to spent petroleum catalyst recovery
units. Thus, EPA solicited comment on the adequacy/efficiency of
existing controls and data quantifying the levels emitted of hazardous
air pollutants (HAPs) regulated under RCRA and/or section 112 of the
Clean Air Act Amendments. The Agency indicated that it had made a
preliminary finding that these units are already equipped with
pollution controls comparable to those required under the BIF rule such
that further regulation may be unnecessary.
Application of the Existing Exclusion for Spent Sulfuric Acid
As described in the proposal, EPA previously excluded from the
definition of solid waste spent sulfuric acid used to produce virgin
sulfuric acid (40 CFR 261.4(a)(7)). The Agency reexamined this
exclusion as it pertains to sulfuric acid used as a catalyst in
refinery alkylation processes and found no reason to change the
existing regulatory structure.
2. Summary of Proposed Risk Assessment Approach
The proposed rule preamble describes in detail the various risk
assessment analyses EPA carried out to determine the potential risk
that might arise from the disposal of the refining wastes under
consideration in this rule (see 60 FR at 57756-57762). In carrying out
the modeling for these assessments, EPA used available data it
collected for this industry, supplemented by data gathered from surveys
of waste management practices (e.g., EPA's National Survey of Solid
Waste (Municipal) Landfill Facilities, 1988, in the docket). The Agency
also used information gathered in a questionnaire prepared under RCRA
3007, hereafter referred to as the ``3007 Questionnaire,'' and site
visits designed to examine the waste characteristics, waste management
practices, and potential pathways for release and exposure.
While EPA used this empirical data as much as possible in its risk
assessment, the Agency nevertheless found that data gaps existed in the
available information. Therefore, EPA also used other generic input
parameters in the fate and transport models used to estimate the risk a
waste might present under management scenarios known or likely to
occur. The Agency used available data to develop input parameters for
the concentrations and toxicity of constituents in the waste, the
mobility and fate of such constituents in different disposal scenarios,
likely exposure routes under these scenarios, and the location of
various persons (``receptors'') that might be exposed. These receptors
might be persons who consume contaminated groundwater, breathe air
containing contaminants, or ingest contaminated soil or food.
EPA considered what waste management scenarios to model, based on
existing and potential practice in the refinery industry. Also
important to the risk analyses are the volumes of wastes disposed and
the potential for constituents in the waste to be released. Total
volumes of waste were derived by multiplying the amount of wastes
disposed in any given year times the active life for the disposal unit
(how long a disposal unit accepts waste before closure). The fraction
of the waste in the disposal unit (waste fraction) was derived from the
total volume of a waste placed in the unit and the unit's capacity.
While various waste management practices were considered, the Agency's
modeling focused primarily on potential releases from waste volumes
sent to nonhazardous (Subtitle D) landfills and land treatment units
(LTUs), both on and off the refinery site (on-site and off-site units).
For on-site, units EPA used the data on unit size available from the
3007 Questionnaire. For off-site landfills, EPA used generic data
available for Subtitle D unit size available from surveys of industrial
and municipal waste management facilities.
To estimate the significance of any potential releases of
constituents from the disposal units and the potential for exposure to
people or the environment, EPA first considered the mode of migration
out of the landfill or LTU. The exposure of most concern for landfills
arises from the release of constituents from the waste to groundwater.
Other exposure routes were considered only in preliminary analyses, and
did not present significant risks. EPA used the Toxicity Characteristic
Leaching Procedure (TCLP) to estimate the mobility of constituents in
leachate that may be released from a landfill to groundwater. EPA also
considered the potential for oil in the wastes to facilitate release
and transport of constituents from landfills by ``oil-phase flow.''
Such facilitated release might occur if free oil in wastes, potentially
containing hazardous constituents, migrated from landfills to
groundwater. However the Agency's analysis showed this type of
facilitated release was not likely. For LTUs, the wastes are mixed with
soils on the surface of the unit. Potential exposure routes of most
concern for land treatment arose from the transport of contaminated
soils to receptors by both wind-borne air releases, and the erosion/
run-off caused by precipitation. Groundwater risks from LTUs were not
found to be significant.
To model the transport of constituents to receptors, EPA typically
used data available from surveys to locate the likely exposure point.
Thus, to assess potential groundwater exposures near landfills, EPA
used national surveys of landfills, which included data regarding
[[Page 42117]]
the distance from landfill units to nearest drinking water well. For
LTUs, EPA used surveys of the distance of residences from such disposal
units. Where appropriate, EPA attempted to consider information related
to the biodegradation some constituents may undergo in the unit or
after release into the environment.
The Agency used comparisons between concentrations in the
environment and health-based levels (HBLs) to evaluate the potential
health impacts of toxic constituents in environmental media, such as
soil or groundwater. For noncarcinogenic constituents, the HBL is the
concentration in the media which results in an exposure level equal to
the ``reference dose;'' the reference dose is EPA's measure of an
acceptable daily intake for a specific chemical. For carcinogenic
constituents, the HBL is the concentration in the media that results in
an exposure level corresponding to a specified cancer risk level. EPA
applied carcinogenic potency estimates (Carcinogenic Slope Factors) to
calculate specific risk levels. The risk assessment results are given
in terms of individual risk, i.e., the carcinogenic risk is described
in terms of the additional incidence of cancer that may occur in an
exposed population. A risk of 1 x 10-5 (which will be
presented in this document as 1E-5), for example, corresponds to a
probability of one additional case of cancer for every 100,000 people
exposed. The Agency also evaluates carcinogenic constituents by
directly calculating the estimated cancer risk level resulting from a
given concentration of the constituent in the environmental media.
In the modeling for risk assessment, EPA varied some of the more
sensitive parameters to examine the range or potential risks presented
by the wastes studied. Key parameters included the area of the waste
disposal units, waste volumes disposed, constituent concentrations in
the wastes, and the distances to receptors. Varying several of these
key parameters at one time can have a large cumulative impact on the
risk results. In view of the variation in individual exposure risks
that could exist for the wastes, EPA performed a number of different
types of risk and sensitivity analyses. First, the Agency completed a
``bounding analysis'' in which the key input parameters were set to
produce a worst-case scenario. This analysis was intended to purposely
overestimate exposure to establish an upper bound for risks. (See the
EPA guidance memo entitled, Guidance on Risk Characterization for Risk
Managers, 1992; docket number F-95-PRLP-S0423, hereafter known as the
Habicht memo, 1992.) Thus, all key parameters were set to their maximum
or ``high-end'' values (typically the 90th percentile point on the
distribution of values available for each parameter). If the risks
resulting from the bounding analysis were below the level of any
potential concern (i.e., carcinogenic risks below 1E-6 and hazard
quotients (HQs) less than one), the wastes and/or waste constituents
were removed from further consideration.
For wastes and constituents that did not ``bound out,'' EPA ran a
double ``high-end'' deterministic sensitivity analysis, which produced
point estimates of risk based on use of single values for input
parameters. In this method, key input parameters were varied between
the central tendency value (50th percentile) and the high-end (90th
percentile) values. The point estimate in which all variables were set
at central tendencies was assumed to be the central tendency risk
estimate. The highest risk estimate for any combination of double high-
end variables (with all other variables set at central tendency) was
assumed to be the high-end estimate of risk. The high-end risk estimate
was presumed by the Agency to be a plausible estimate of individual
risk for those persons at the upper end of the risk distribution. The
intent of these descriptors is to convey estimates of exposure in the
upper end of the distribution (i.e., above the 90th percentile) and to
avoid estimates that are beyond the true distribution.
After completing these various analyses, EPA compared individual
exposure levels to HBLs for the toxic constituents to determine whether
particular wastes are candidates for listing. In keeping with
discussions of the Agency's listing policy (see Dyes and Pigments
Listing, 59 FR at 66075-66078), EPA used a risk level of concern of 1E-
5, and/or HQs of one, to determine which wastes are considered initial
candidates for listing. To make listing determinations, EPA then used a
weight-of-evidence approach that considers the risk estimates along
with other evidence related to the factors described in 40 CFR
261.11(a)(3).
Based on EPA's analysis for the proposed rule, the exposure pathway
of concern for the landfill scenario was ingestion of groundwater
contaminated by constituents leaching out of the unit. For the land
treatment scenario, the potential release of wastes by air or run-off
yielded exposure for nearby residents and home gardeners via soil
ingestion and for other subpopulations (fishers, farmers) through
indirect exposures, i.e., via ingestion of contaminated fish and food.
These analyses led to the proposed listing decisions as explained in
the preamble to the proposed rule.
C. Notice of Data Availability
Many issues were raised by commenters on the proposed rule causing
EPA to rethink its analyses and the risk assessments. These issues are
discussed in the April 8, 1997 NODA (62 FR 16747) and the accompanying
support documents. EPA conducted new risk assessments for both
groundwater and non-groundwater pathways, in addition to analyses for
the headworks exemption, recycled hydrocarbon-bearing materials, and
leaching of oily wastes. This new information was presented for
comment. At the time, EPA believed that the additional analyses tended
to support the proposed rule and did not propose any new listing
decisions. Important additional analyses provided in the NODA are
briefly described below.
The NODA provided revised ``high-end'' analyses for the landfill
and LTU scenarios. In the groundwater analysis, EPA completed more
detailed sensitivity analyses and Monte Carlo analysis to better define
high-end risks, and determine how close the high-end risks, were to the
90th percentile.
The Agency has been using Monte Carlo modeling methodology in
various rulemakings for many years. Monte Carlo modeling is a
statistical technique that can be used to simulate the effects of
natural variability and informational uncertainty which often accompany
many actual environmental conditions. It is a process by which an
outcome is calculated repeatedly for many situations, using in each
iteration randomly selected values from the distributions of each
variable input parameter. When compared with alternative approaches for
assessing parameter uncertainty or variability, the Monte Carlo
technique has the advantages of general applicability and no inherent
restrictions on input distributions or input-output relationships.
Monte Carlo application results can also be used to calculate
uncertainty, and can be used to quantitatively specify the degree of
conservativeness used. However, potential limitations also exist when
applying Monte Carlo techniques in modeling efforts. Variability
(inherent variation in a measure over time and space) and uncertainty
(lack of knowledge) may be difficult to distinguish within
applications. Also, correlations among the various data parameters that
have not been accounted for in the modeling may
[[Page 42118]]
distort conclusions. Finally, sufficient data must generally be
gathered to ensure that acceptable statistical representations and
sensitivity analyses within Monte Carlo applications can be properly
prepared.
The Monte Carlo simulations used in this rulemaking assessed the
full distributions of critical input data (e.g., distance to well,
waste volumes, landfill area) to randomly generate receptor well
concentrations of key constituents for certain landfill situations, and
then combined the results from many runs (10,000) to produce a
probability distribution of risks. EPA was then able to choose points
along the probability distribution of risk for comparison to the high-
end analysis. For example, a risk that corresponds to the 95th
percentile for a specific waste constituent in a landfill means that
the risk would be below this level in 95 percent of the runs. EPA also
modified all groundwater risk analyses to add risks due to noningestion
exposures (e.g., via inhalation and dermal absorption during showering)
to the ingestion risks that may arise from residential use of
groundwater.
Further groundwater analysis was also performed in response to
comments on the proposed rule that noted EPA had used waste input data
(TCLP) that exceeded the existing Toxicity Characteristic (TC)
threshold and that disposal in nonhazardous landfills was unlikely for
such wastes. This additional groundwater analysis limited the TCLP
input used in modeling, such that none of the input levels exceeded the
TC threshold, to examine the impact on risk results (the ``TC-capped''
analysis).
In the nongroundwater analysis presented in the NODA, EPA
incorporated several modifications for LTUs, including: limiting wastes
volumes modeled to nonhazardous waste; limiting unit characteristics
used (e.g., unit area) to nonhazardous units; correcting an error in
the air dispersion modeling; minor changes to the models used to
estimate release and transport of contaminated soil to off-site
receptors; and incorporating further biodegradation of key constituents
after they travel off-site.
The appropriateness of the TCLP for petroleum wastes containing oil
and the potential for oil and other materials to facilitate release and
transport of wastes in landfills were major areas of comment. EPA
provided additional information in the NODA to respond to this issue,
including; analysis of the oil content of the waste samples, the
prevalence of disposal of oily waste in landfills, analysis using
alternative leaching procedures, and calculated TCLP leaching
efficiencies for organic constituents in the wastes.
EPA received comments on its choice of management practices modeled
and the way volumes were allocated. Some commenters also suggested that
volumes of wastes beyond those under consideration in this rule should
have been considered in various codisposal scenarios for both landfills
and LTUs. In response, EPA presented risk analyses in the NODA that
assessed the potential impact of codisposal of the listing residuals
with certain other refinery wastes.
In the NODA, EPA presented additional analyses to address comments
on the headworks exemption for CSO storage tank sediment. While some
commenters did not favor the exemption due to potential impacts on
downstream wastes, other commenters argued the exemption should be
expanded to exclude wastewater from spent hydrotreating and
hydrorefining catalysts, the other two wastes EPA proposed for listing.
The Agency evaluated the potential impact of including wastewater from
these three wastes in the headworks exemption, and presented the
results in the NODA that showed excluding them would not result in any
significant risks in the downstream wastes.
Comments on the proposal suggested that the active life for a
landfill used by EPA was too short. This parameter is important because
it determines the total waste volume in the modeled landfill, which is
one of the critical input parameters for the model. To respond to this
comment, EPA presented data in the NODA for on-site landfills to show
that the data in the 3007 Questionnaire supports the Agency's
assumption of a 20-year active life.
The NODA also presented other information related to: the potential
impact of the oil-bearing residuals exclusion on coke product, the
potential for concurrent exposure to releases from landfills and LTUs,
and the applicable UTS under the Land Disposal Restrictions program.
IV. Changes to the Proposed Rule
As a result of comments on the proposed rule and NODA analyses,
certain modifications were made to the listing determinations and
definition of solid waste exclusions. These changes and the subsequent
scope of today's final action are described below. Detailed reasoning
behind these changes is provided in Section V.
A. Definition of Solid Waste Exclusions
1. Exclusion of Oil-Bearing Hazardous Secondary Materials Inserted Into
Petroleum Refining, Including Petroleum Coking
Today, the Agency is finalizing a portion of the proposed exclusion
for oil-bearing hazardous secondary materials recycled within the
petroleum industry. Specifically, oil-bearing hazardous secondary
materials generated within the petroleum refining sector (i.e., SIC
code 2911, petroleum refineries) are excluded under today's rule when
they are to be inserted into the petroleum refining process, including
into the petroleum coker, provided they are not placed on the land or
speculatively accumulated before being so recycled. As discussed below,
this exclusion applies to any oil-bearing material generated at a
petroleum refinery, including oil-bearing wastes currently regulated as
listed hazardous wastes (e.g., K048-K051), and including refinery
wastes newly listed under today's rulemaking that are suitable for
insertion into normal petroleum refining operations. EPA is not
finalizing the proposed exclusion for oil-bearing hazardous secondary
materials generated elsewhere within the petroleum industry, such as
from petroleum exploration and production sites, bulk crude oil
storage, and petroleum industry-related transportation facilities.
However, the pre-existing recovered oil exclusion promulgated July 28,
1994, is still being retained under today's rule with respect to
recovered oil generated from within the petroleum industry. EPA is also
modifying an existing petroleum-industry listing (F037) to make it
apply to discarded residues generated from processing or recycling
petroleum-industry listed hazardous wastes that are otherwise excluded
under today's provision.
The Agency notes that this exclusion will have little net effect on
the materials or units involved. Under the current regulatory program
(i.e., prior to today's amendments), oil-bearing secondary materials
may legitimately be recycled into a petroleum coker. While such
materials may be considered solid and hazardous wastes, the coking unit
would be a recycling unit exempt from permitting requirements (40 CFR
261.6(c)(1)). The coke product is exempt under 40 CFR 261.6(a)(3)(v),
provided the secondary materials are generated by the same ``person,''
defined in 40 CFR 260.10 as ``an individual, trust, firm, joint stock
company, Federal agency, corporation (including a government
corporation), partnership, association,
[[Page 42119]]
State, municipality, commission, political subdivision of a State, or
any interstate body,'' and the petroleum coke does not exhibit a
characteristic of hazardous waste. The oil recovered in the coking
operation (including both conventional coking and the quenching
process) which is used to produce fuels is excluded from the definition
of solid waste as recovered oil under 40 CFR 261.4(a)(12).
2. Recovered Oil From Associated Petrochemical Facilities
In today's final rule, EPA is finalizing a somewhat narrower
exclusion than originally proposed. Specifically, EPA proposed to
exclude recovered oil from ``associated organic chemical manufacturing
facilities'' where such facilities were defined as those within the SIC
code 2869 and either co-located or under common ownership with the
petroleum refinery receiving the petrochemical recovered oil. In
today's rule, EPA is dropping ``under common ownership'' from the
definition of ``associated organic chemical manufacturing facility''
for reasons discussed later. In addition, EPA is limiting the
applicability of the final exclusion to petrochemical recovered oils
that are hazardous only because they exhibit the characteristic of
ignitability (as defined in 40 CFR 261.21) and/or toxicity for benzene
(40 CFR 261.24, waste code D018). Finally, in today's rule, EPA is also
excluding petrochemical recovered oil generated at facilities where the
primary SIC code is 2869, but where three other classifications of
chemical manufacturing units commonly occur at these vertically-
integrated facilities (SIC codes 2821, 2822,2865).
3. Use of Spent Caustic as Feedstock
Today EPA is finalizing the exclusion proposed for spent caustic
solutions from petroleum refining when used as feedstocks to produce
cresylic or naphthenic acid. This new exclusion is being added at 40
CFR 261.4(a)(19).
B. Listing Determinations
Table IV-1 presents a summary of changes to the proposed listing
decisions. Detailed bases for today's final listing determinations are
discussed in Section V.C for each specific waste.
Table IV-1.--Comparison of Proposed and Final Listing Decisions
--------------------------------------------------------------------------------------------------------------------------------------------------------
Waste Stream 1995 Proposal Final decision Basis for decision
--------------------------------------------------------------------------------------------------------------------------------------------------------
Hydrotreating Catalyst.............. List............................ List........................... Groundwater risks due to benzene and arsenic
from landfill disposal; pyrophoric and self-
heating nature of waste.
Hydrorefining Catalyst.............. List............................ List........................... Groundwater risks due to benzene and arsenic
from landfill disposal; pyrophoric and self-
heating nature of waste.
CSO Storage Tank Sediment........... List............................ List........................... Nongroundwater risks due to PAHs from land
treatment disposal; some groundwater risks due
to benzene from landfill disposal; high PAH
and oil content.
Crude Oil Tank Sediment............. No-list......................... List........................... Groundwater risks due to benzene from landfill
disposal; PAH and oil content.
Unleaded Tank Sediment.............. No-list......................... No-list........................ Some groundwater risks due to benzene from
landfill disposal, but no significant PAH or
oil content; relatively low volume.
HF Alkylation Sludge................ No-list......................... No-list........................ Relatively low groundwater risks due to benzene
from landfill disposal; no significant PAH
content; benzene found in only one TCLP
sample.
Off-specification Product & Fines... No-list......................... No-list........................ Low groundwater risks due to PAHs from landfill
disposal; PAHs only found in one TCLP sample
near detection limit.
Other Wastes \1\.................... No-list......................... No-list........................ No significant risks from any pathway.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Includes seven wastes: Catalyst from Sulfuric Acid Alkylation, Sludge from Sulfuric Acid Alkylation, Spent Caustic from Liquid Treating, Catalyst
and Fines from Catalytic Cracking, Sludge from Sulfur Complex and Hydrogen Sulfide Removal Facilities, Catalyst from Sulfur Complex and Hydrogen
Sulfide Removal Facilities, and Catalyst from Reforming.
In response to additional comments submitted on the NODA, the
Agency further examined the record and reconsidered the entire risk
assessment and decisions for all the wastes under consideration.
Commenters on the NODA provided detailed comments on the groundwater
modeling approach used by EPA. Some commenters submitted their own
groundwater modeling, purporting to show higher risks than EPA's
evaluation for a number of wastes. While the commenters used the same
model as EPA (EPACMTP), they adjusted key input values to increase
landfill area, increase active life of landfills and resulting volume
disposed, move the receptor well location to the middle of the plume of
contamination, increase TCLP concentrations using simplifying
assumptions, and increase volumes due to codisposal. To respond fully
to critical issues raised in comments on the groundwater risk analysis,
EPA decided to make modifications to some modeling assumptions and data
inputs. EPA examined the impact of other suggestions by the commenters,
but found these to be of no importance or did not agree that the
changes were warranted. The changes to the modeling, and EPA's reasons
for not accepting other suggestions, are discussed in detail in Section
V.B.
Specifically, in response to NODA comments, EPA decided that some
revisions in the modeling assumptions were appropriate. Thus, the
Agency performed additional risk analyses to reflect an increase in the
active life for off-site landfills (which resulted in increased volume
input to the modeling), and the use of off-site municipal landfill area
distributions, rather than the areas for industrial landfills used
previously. With these changes, the final revised high-end and Monte
Carlo risks increased somewhat from those presented in the NODA for
off-site landfills and are summarized in Table IV-2. Also, in
conducting the Monte Carlo analysis for the NODA, the Agency made a key
assumption concerning well location which was inconsistent with the
assumption made for the high-end analysis (see discussion of receptor
well location in Section V.B.6). Therefore, EPA performed further Monte
Carlo analyses using well location assumptions consistent with the
high-end analysis, and the results show that this also increases risks,
such that the 95th percentile Monte Carlo risks are more comparable to
the high-end risks. Finally, while reexamining the groundwater risk
analysis for off-specification products and fines, EPA corrected errors
in waste volumes and a
[[Page 42120]]
health-based level used for prior analyses.
(See Additional Groundwater Pathway Risk Analyses, 1998, in the public
docket for this rule for details on the revised analyses.)
The final risk results for off-site landfills, with the changes
noted above, are summarized in Table IV-2 for wastes of concern. Other
wastes either did not have significant risk in bounding analyses, or
were not modeled for landfill disposal because the practice was not
found.
Table IV-2.--Summary of Revised Groundwater Risks for Petroleum Wastes in Off-Site Landfills
--------------------------------------------------------------------------------------------------------------------------------------------------------
Revised risks \1\ TC-capped risks \2\
-------------------------------------------------------------------------------
Waste Constituent Monte Carlo Risk Monte Carlo risk
High-end risk \3\ \4\ (95th%) High-end risk (95th%)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Clarified Slurry Oil Tank Sediment. benzene............................ 4E-06 2E-06 NC NC
Hydrotreating Catalyst............. benzene............................ 1E-04 3E-05 3E-05 9E-06
arsenic............................ 8E-05 2E-05 NC NC
Hydrorefining Catalyst............. benzene............................ 7E-05 2E-05 3E-05 8E-06
arsenic............................ 6E-04 4E-04 6E-04 4E-04
Crude Oil Storage Tank Sediment.... benzene............................ 4E-05 1E-05 3E-05 9E-06
Unleaded Gasoline Storage Tank benzene............................ 3E-05 6E-06 2E-05 4E-06
Sediment.
HF Alkylation Sludge............... benzene............................ 1E-05 2E-06 NC NC
Off-Specification Product and Fines benzo(a)anthracene................. 2E-06 \5\ 1E-06 NC NC
5E-07 \6\ 8E-07
Codisposal Scenario................ benzene............................ 8E-06 3E-06 NC NC
arsenic............................ 4E-06 2E-06 NC NC
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Revised risk includes new inputs for active landfill life (30 yr.) and municipal landfill areas.
\2\ Input leaching rates were capped at TC regulatory levels for disposal in Subtitle D landfills (0.5 mg/L for benzene and 5.0 mg/L for arsenic); NC =
no change because TCLP values were already below TC levels.
\3\ Risks using high-end values for two most sensitive parameters, and remaining parameters kept at median values.
\4\ Risks using Monte Carlo simulation runs at the 95th percentile level with well location restricted to plume.
\5\ Estimated TCLP input assumed to be mean value.
\6\ Estimated TCLP input assumed to be one high-end parameter.
The nongroundwater risk results for land treatment are unchanged
from those reported in the NODA (see 62 FR at 16753). However, in
response to comment EPA performed a Monte Carlo uncertainty analysis
for land treatment risks that supports the results presented in the
NODA. See Section V.B of today's notice for further discussion of this
issue.
The revised groundwater risk assessment for landfills, in
conjunction with the nongroundwater assessment for land treatment
disposal presented in the NODA, continues to support the proposed
listing of K170, K171, and K172. Therefore, EPA is promulgating these
listings in today's final rule, with minor modifications to clarify the
definition of the two spent catalysts (see Section V.C.3).
K171--Spent hydrotreating catalyst from petroleum refining
operations, including guard beds used to desulfurize feeds to other
catalytic units. (This listing does not include inert support
media.)
K172--Spent hydrorefining catalyst from petroleum refining
operations, including guard beds used to desulfurize feeds to other
catalytic units. (This listing does not include inert support
media.)
In addition, EPA has determined that the available information and
the revised groundwater risk assessment provides sufficient basis to
list as hazardous crude oil storage tank sediment, and to have the
waste designation of K169. The listing will read:
K169--Crude oil storage tank sediment from petroleum refining
operations.
All final listing determinations depend upon EPA's consideration
and review of public comments submitted in response to the proposed
determinations, issues raised in the NODA, and any other relevant
information available to the Agency. The final determinations are based
on the Agency's evaluations as to whether the wastes meet the criteria
in 40 CFR 261.11(a) for listing wastes as hazardous. EPA has assessed
and considered the factors contained in these criteria primarily by
incorporating them as elements in the revised risk assessment, which is
based on the methodology described in the preamble to the proposed rule
and subsequent modifications described in this preamble and in support
documents in the rulemaking record. EPA bases its final listing
determinations on the entire rulemaking record, including applicable
sections of the preamble to the proposed rule, additional analyses
provided in the NODA, the Agency's responses to the comments on
significant issues raised in the preamble to the proposal and the NODA,
and all other relevant information available to the Agency.
C. Other Exemptions
1. Headworks Exemption
EPA presented analysis in the NODA to support the headworks
exemption for both wastewater associated with CSO tank cleaning and the
expansion of the exemption to include water discharges from the clean-
out and turn around of hydrotreating and hydrorefining catalytic units.
After considering all comments on these analyses, EPA has decided to
promulgate the expanded headworks exemption. As noted in the proposal,
EPA intended to include crude oil storage tank sediment in the
exemption, if this waste was listed. Thus, EPA is also promulgating the
exemption for K169 as well. To fully respond to all comments, EPA
completed an analysis of the impact of the discharge of crude oil
storage tank sediment to the wastewater treatment system, which
demonstrates that the discharge is unlikely to adversely impact
downstream wastes. This decision is discussed in V.D, and supporting
analyses are presented in the docket for this notice.
In amending the headworks exemptions under 40 CFR
261.3(a)(2)(iv)(C), the Agency intends the exemption to apply to
wastewaters from cleaning operations when these wastewaters reach the
headworks of the wastewater treatment system. As noted
[[Page 42121]]
in the proposal, however, the exemption is not intended to allow the
discharge of the entire waste stream (i.e., tank sediments or spent
catalysts), but rather dilute waters generated during tank or unit
clean-outs and dewatering operations.
2. Exemption for Catalyst Support
The Agency is finalizing the proposed exemption (under 40 CFR
261.3(c)(2)(ii)) for these support media because the support media are
generally inert materials and commonly managed separately. EPA is
clarifying the exemption so that it is no longer limited to ceramic
material, based on comments indicating that other inert materials, such
as stainless steel, are also used.
3. Third Party Recycling of Spent Petroleum Catalysts
EPA does not believe at this time that it is appropriate to issue
the proposed clarification to exempt, from permitting requirements
under Part 266.100(b), third party units regenerating and reclaiming
hydrotreating and hydrorefining spent catalysts. EPA is deferring to a
later day any final decision on whether or not to clarify the BIF rule
with respect to these wastes. In the meanwhile, EPA reiterates that
nothing in today's rule (or indeed the proposal in this docket) changes
the current RCRA status of facilities managing these hazardous wastes.
(See Section V.E. for further discussion of this decision.)
V. Response to Comments and Rationale for Final Rule
The Agency is responding in this preamble to the most significant
comments received in response to both the notice of proposed rulemaking
and the NODA. Other comments received by the Agency are addressed in
the Response to Comments Background Documents that are available in the
docket associated with this rulemaking.
A. Proposed Modifications to the Definition of Solid Waste
1. Exclusion of Oil-Bearing Hazardous Secondary Materials Inserted Into
Petroleum Refining, Including Petroleum Coking
Role of the Petroleum Coker in the Petroleum Refining Process
To determine RCRA jurisdiction, the Agency must differentiate
between materials that are part of normal ongoing production activities
and materials that are part of waste management, including recycling or
treatment. Distinguishing waste management from normal production can
sometimes be difficult when it involves hazardous secondary materials
generated by certain production processes and used as feedstocks in
other production processes within the same industry that produce a
relatively low-value product (especially hazardous secondary materials
that have sometimes been discarded in the past). (see 50 FR at 618-620,
Jan. 4, 1985). Regarding the petroleum refining production process,
classification of the coking operation has been historically
troublesome in delineating production from waste management because it
is not typical of other refining processes.
Generally, and in the most basic of terms, petroleum refining
processes serve to separate and remove hydrocarbon components out of a
feedstream, in effect constituting a multi-stage process of separating
valuable product materials from the contaminants (e.g., sulfur and
metals) inherent in the original raw material (crude oil). In the
coking process, however, the contaminants inherent in the crude oil
feedstock are incorporated into the fuel product, along with the carbon
that results from the thermal breaking of complex hydrocarbon chains
into more valuable small- and middle-chain oil fractions (see detailed
description of conventional coking versus the quenching process in
Section III.A.1.).
EPA first evaluated whether the conventional coking operation is a
true production process because the crude oil distillation bottoms,
i.e., resids, used as feedstock contain many of the unwanted
contaminants in the original crude oil which end up in the coke product
(a low-value fuel product, relative to the other fuel products produced
by petroleum refining) and because a majority of the coke product is
exported rather than being used within the United States. As stated
earlier, this is not typical of a petroleum refining process producing
a fuel product. Thus, an argument could be made that the petroleum
coker is simply a means of disposing of unusable heavy oils and other
contaminants associated with crude oil feedstocks (including hazardous
heavy metals), while producing a relatively low-value fuel.
However, the American Petroleum Institute (API) supplied the Agency
with detailed information regarding the conventional coking operation,
presenting a description of the physical processes involved in the
coking process and the economic value of the overall coking operation
to the refinery, as well as the feedstocks used and products produced.
As discussed in the November 20, 1995, proposal preamble (60 FR at
57754), the Agency has determined that the use of resids as feedstock
to the petroleum coker is a legitimate production process whose main
purpose is to thermally convert the heaviest crude oil fractions into
light-end hydrocarbons (typically about 70 percent of the feedstock is
recovered as lighter oil fractions) used as feedstocks for refinery
processes that produce high-value fuel products. In many cases, the
conventional coking operation is essential to the profitable production
of petroleum products from heavier crude oil feedstocks, being a cost-
effective process for maximizing the amount of hydrocarbon that can be
recovered from the crude oil feedstocks. The coke product itself may
best be characterized as a co-product of the coking operation, while
the principal products are the light ends that are returned to the
refining process. Thus, the Agency is affirming that the conventional
coking operation is a production process resids are normal feedstocks
to this process and petroleum coke is a legitimate fuel product
(although EPA in fact notes that high-grade petroleum coke meeting
relatively exacting specifications is used for producing anodes for use
in electric furnaces, such as for steel and aluminum manufacturing).
However, the fact that the Agency considers the conventional coking
operation to be a normal production process does not mean that any
material introduced to the coking operation is, by definition, part of
a normal production process. Indeed, when considering the regulatory
status of hazardous secondary materials not typically used as
feedstocks being introduced into such a process, the Agency must
consider whether such use of the secondary materials is legitimate use
in a production process, or rather is sham recycling where unwanted
contaminants are being removed of under the aegis of an ostensible
manufacturing operation. Typically, this is evaluated through a
comparison to the normal feedstocks, with particular focus given to
whether there are hazardous constituents contained in a hazardous
secondary material that are not found in the normal feedstock materials
for which it is substituting (see 50 FR at 638, Jan. 4, 1985). EPA
received many comments relevant to the exclusion for the hazardous
secondary materials inserted into the petroleum coker, especially the
quenching process, both supporting and opposing to the exclusion. Much
information, both anecdotal and analytical data, was received
concerning various aspects of
[[Page 42122]]
the overall coking operation. This information included the constituent
composition of the hazardous oil-bearing secondary materials at issue,
the normal coker feedstocks, various aspects of the overall coking
operation, the coke product, and the marketing of petroleum coke. The
Agency made a very considered evaluation of all of the information
provided in comment to the proposal, much of which was contradictory
and difficult to confirm. The discussion below presents the Agency's
reasoning in making its determination.
Use of Hazardous Secondary Materials in the Petroleum Coker
The Agency evaluated information received on the role of oil-
bearing hazardous secondary materials in the coking operation. As
discussed more below, the oil-bearing hazardous secondary materials
typically put into the coker unit are unable to be processed via
conventional coking because of their high water content (the water
would volatilize and create unsafe pressures during the conventional
coking process). Therefore, the Agency's evaluation centered around the
role of these secondary materials in the quenching process, described
in more detail in Section III.A.1. of today's preamble. In evaluating
this information, the Agency's focus was to determine whether the use
of oil-bearing hazardous secondary materials in the quenching process
is consistent with the role of oil-bearing feedstocks in the
conventional coking process, i.e., to provide hydrocarbon for further
refining and to contribute carbon to the coke product. (EPA's reasoning
is that it is the recovery of hydrocarbon and production of coke that
is the intent of the overall coking operation, and thus the legitimate
use of a hazardous secondary material in the quenching process should
likewise contribute to this intent.) This evaluation compared not only
the constituent make-up of the feedstocks to both conventional coking
(resids) and to the quenching process (hazardous secondary materials),
but also what physical/chemical processes occur in both aspects of the
coking operation. The discussion that follows presents the Agency's
evaluation.
In comparing the typical hazardous secondary materials used in the
quenching process (i.e., listed hazardous wastes, primarily wastewater
treatment sludges) to the residues normally used as feedstocks to
conventional coking, the oil content in the hazardous secondary
materials is much lower (ranging from around 8 percent to 40 percent in
the hazardous secondary materials to around 99 percent in the crude oil
distillate bottoms), while the water content is much higher. The
hazardous constituents (primarily heavy metals) in the secondary
materials are measurably higher. However, as stated above, the
hazardous secondary materials are not used in conventional coking, but
rather are used in the quenching process. Therefore, a comparison of
the hazardous secondary materials to the resids feedstock has limited
value and is not dispositive for determining the legitimacy of the
activity, because the hazardous secondary materials are not
substituting for the feedstock, but are instead being processed in a
different manner than the conventional coking feedstocks.
As described earlier, there are two aspects of the coking operation
for the Agency to consider: (1) conventional coking--which entails the
application of high temperatures to the heavy oil-bearing feedstock in
the coke drum in order to break the complex hydrocarbon chains into
lighter chains that are recovered for further refining, also resulting
in the production of coke product, and (2) the quenching process--
which, for the purposes of the Agency's evaluation in today's
rulemaking, entails the insertion of oil-bearing hazardous secondary
materials along with, or just prior to, water used to quench the coke
product before removal from the coke drum.
Because the hazardous secondary materials are not processed along
with the normal feedstocks to the coker, but rather are introduced into
the coke product during the quenching process, the assessment of
``legitimacy'' becomes somewhat more difficult since there is no
analogous raw material. (The Agency notes that this is typically the
situation when determining the applicability of RCRA regulations to
secondary materials used in connection with innovative technologies or
practices.) The hazardous secondary materials are typically mixed with
water to form a slurry that is injected into the coke at the beginning
of the quench cycle (in some cases, the secondary materials are not
slurried and are inserted ahead of the quench water). The hazardous
secondary materials are unable to be used in conventional coking
because of their high water content; however, the water content is not
detrimental during the quenching process. Thus, in determining the
legitimacy of this activity, the task at hand is not a straightforward
comparison with analogous nonwaste feedstocks, but rather an evaluation
of the processing that occurs when these hazardous secondary materials
are used in the quenching process, to determine whether this activity
may be characterized as a ``normal'' production activity or whether it
is better characterized as hazardous waste recycling, or even simply
the disposal of hazardous wastes (i.e., sham recycling).
Indeed, some commenters opposed to the use of hazardous secondary
materials in the petroleum coker raised the concern that the use of
listed hazardous wastes in the quenching process is simply a means of
disposing of RCRA hazardous wastes in a low-value product, much of
which is exported overseas, and that if these materials truly had value
to the coking process, they would be used as feedstock in the
conventional coking process. Since it is obvious that these secondary
materials would otherwise be hazardous wastes that would be treated and
disposed of if not used in the quenching process, it would seem to be a
simple matter, as some commenters have suggested, to ascribe a simple
waste disposal motive to this activity and nothing more.4
However, the Agency is compelled to go further and determine whether
the oil-bearing secondary materials actually contribute to the product
and/or process, or otherwise determine whether there is a production-
related value to this activity.
---------------------------------------------------------------------------
\4\ Indeed, internal industry literature, as well as public
statements made by industry representatives, relevant to the use of
hazardous secondary materials in the quenching operation would lead
one to believe that the principal purpose of this activity is to
dispose of hazardous waste sludges (see the January 9, 1998 letter
from Richard Fortuna to Mike Shapiro); however, the Agency does not,
as a rule, take such statements as determinative and evaluates the
activity independent of how the process may have been characterized
in other contexts. The Agency would do the same in situations where
all such industry statements would indicate that a particular
process is legitimate production, i.e., evaluate the merits of the
activity independent of statements from interested parties.
---------------------------------------------------------------------------
The petroleum industry, on the other hand, believes that such an
evaluation is unnecessary. Industry representatives argue that oil-
bearing secondary materials used in the quenching process for
legitimate recovery of hydrocarbon as either a light oil fraction or by
incorporation in petroleum coke can never be a solid waste, i.e., that
these materials must be excluded from being RCRA solid wastes as a
matter of law.5 Their argument is based on the initial case
considering the scope of the statutory term ``solid waste,'' namely the
first AMC I decision. In that decision, the Court held that ``materials
that are recycled and reused in an ongoing manufacturing or industrial
process''
[[Page 42123]]
were not yet discarded and hence not ``solid wastes.'' (see 824 F.2d at
1186).
---------------------------------------------------------------------------
\5\ See January 23, 1998 letter from Paul Bailey to Michael
Shapiro.
---------------------------------------------------------------------------
EPA disagrees that an exclusion is compelled (even assuming
legitimate recycling is occurring). First, there is direct case
authority that secondary materials which originate from wastewater
treatment systems can be considered to be ``discarded'' (see AMC II,
907 F.2d at 1186 (``Nothing in AMC I prevents the agency from treating
as `discarded' the wastes at issue in this case, which are managed in
land disposal units that are part of wastewater treatment systems,
which have therefore become `part of the waste disposal problem,' and
which are not part of ongoing industrial processes'' (emphasis
original)). Industry indicates that, primarily, the oil-bearing
hazardous secondary materials utilized in the quenching process are
wastewater treatment sludges (chiefly K048, F037, and F038), which are
thus directly analogous to the sludges at issue in the AMC II decision,
and thus could be considered to be discarded.
These sludges likewise could be considered to be solid wastes
pursuant to RCRA section 3004(q)(2)(A) which indicates that certain
provisions otherwise applicable to hazardous waste-derived fuels do not
apply to petroleum coke produced from ``petroleum refinery wastes
containing oil which are converted into petroleum coke at the same
facility at which such wastes were generated.'' The plain language of
the provision can be read to cover the activity at issue here, and thus
indicate that wastewater treatment sludges and other hazardous
secondary materials going to quench coking could be classified as solid
wastes. 6
---------------------------------------------------------------------------
\6\ The AMC I court gave this provision a restrictive reading,
stating (somewhat circularly) that is applied only to material that
had already become a hazardous waste (824 F. 2d at 1188.) However,
given the holding of AMC II that wastewater treatment residuals can
be classified as solid wastes and that wastewater treatment
operations break any chain of what must be regarded as a continuous
industrial process, the wastewater treatment sludges destined for
the quenching process could be classified as being hazardous wastes.
---------------------------------------------------------------------------
More basically, EPA does not regard the use of oil-bearing
wastewater treatment sludges in the quenching process to be the type of
operation which must necessarily be classified as part of an ongoing
manufacturing process. The parts of the petroleum refining process
outside the Agency's RCRA jurisdiction involve the sequential
distillation of crude oil into various fractions such as gasoline, fuel
oil, asphalt, and conventional coking. (see 824 F.2d at 1181). However,
the quenching process need not be viewed as one more ongoing step in
this process. Not only is there the temporal interdiction of the
generation of wastewater and subsequent management of the wastewater
and sludges in the refinery's wastewater treatment system, but the
quenching process differs in material ways from the standard refining
operations. As discussed above, the materials utilized have less oil,
higher percentages of unusable materials, and the process generates
less recovered oil than any other unit operation in the conventional
refining process. The Agency thus does not accept the argument that
exclusion of hazardous secondary materials used in the quenching
process is legally compelled.
This is not to say that the Agency lacks the discretion to make
such a determination. The term ``discarded'' is ambiguous, and within
the Agency's authority to interpret consistent with the general goals
and policies of the statute. (See AMC II, 907 F. 2d at 1186; American
Petroleum Inst v. EPA, 906 F. 2d 726, 741 (D.C. Cir. 1990)). Among
these goals, of course, is encouraging environmentally sound recycling
(see RCRA section 1003(a)(6)). Moreover, assessing what can permissibly
be classified as continuous industrial processes, and which types of
material recovery operations are ``not part of the waste disposal
problem'' (AMC II, 907 F.2d at 1186), are the types of technical and
policy questions particularly committed to EPA's expert discretion. It
is that discretion which the Agency is exercising in determining in
this rule that a conditional exclusion is appropriate for certain
hazardous oil-bearing secondary materials used in the coke quenching
process.
In describing the use of oil-bearing secondary materials in the
quenching process, industry claims that, similar to the process of
coking resids feedstock, the oil contained in the secondary materials
is either volatilized and condensed for further refining into high-
value fuels, or is incorporated into the coke product. This activity
may be characterized as the efficient use of existing heat energy in
the hot coke to recover the oil contained in the sludges, oil which
would otherwise not be recovered (the temperature of the coke is
approximately 800-900 degrees F before it is quenched). The oil that is
not volatilized gets incorporated into the coke product, adding to the
coke's energy value. The quenching process is operated such that the
slurry is discontinued once the coke reaches the temperature of
approximately 600 degrees F because, at this temperature, the oil is
less likely to volatilize and is primarily incorporated into the coke.
(The coke product then continues to be quenched with water.) While the
oil adds energy value, too much oil causes the coke product to actually
lose economic value. Not only does too much oil make the coke difficult
to handle, it also increases the Volatile Combustible Material (VCM)
level, one of the product specifications for petroleum coke. If the VCM
is too high, the marketability of the coke decreases. 7
---------------------------------------------------------------------------
\7\ See the September 3, 1997, letter from Kyle Isakower to
William Brandes and the January 23, 1998, letter from Paul Bailey to
Michael Shapiro.
---------------------------------------------------------------------------
The Agency solicited further information from industry to
demonstrate the recovery efficiency of the oil contained in the
hazardous secondary materials used in the quenching process. EPA
believes that a comparison of the recovery efficiency of the quenching
process to the recovery efficiency of the conventional coking process
(of the resids) would provide some indication of how ``production-
related'' the use of the hazardous secondary materials in the quenching
process is (i.e., the more similar the quenching process is to the
conventional coking process in the recovery of hydrocarbon values, the
more it may be considered analogous to, or a component of, the coking
process). The data supplied indicate that the recovery efficiency of
oil contained in the secondary materials during the quenching process
is comparable to the recovery efficiency from the feedstock side of the
coking operation. 8 Thus, although the oil content in the
hazardous secondary materials is markedly less, at the very least,
there is demonstrated hydrocarbon recovery from the secondary materials
used in the quenching process, which is consistent with the overall
production intent of petroleum refining.
---------------------------------------------------------------------------
\8\ See January 23, 1998, letter from Paul Bailey to Michael
Shapiro.
---------------------------------------------------------------------------
The Agency notes that one major point of contention between those
commenters opposed to the exclusion and those supporting the exclusion
is whether there is actual evidence that oil (or hydrocarbon value) is
recovered during the quenching process. As stated previously, the oil
content of the oil-bearing hazardous secondary materials typically used
in the quenching process varies considerably (8 to 40 percent),
although the typical secondary materials have an oil content around 10
percent. 9 In determining the oil recovery efficiency of the
quenching process (i.e., a quantification of how much of the oil
contained in the secondary materials is
[[Page 42124]]
actually volatilized and recovered for further refining versus how much
oil is simply incorporated into the coke product), EPA encountered
difficulty in getting any actual data. The data the Agency primarily
relied on were derived from surrogate tests (i.e., tests designed to
simulate the conditions the secondary materials encounter during the
quenching process) performed on the secondary materials typically used
in the quenching process. 10 This is because coking
operations (particularly the capture and condensing of the light-end
hydrocarbons) do not avail themselves to the type of quantifiable
measurements that the Agency prefers. Regarding the quenching process,
this is even more the case. However, surrogate tests may actually be
more representative of the oil recovered from secondary materials used
in the quenching process than actual measurements taken during the
quenching process. This is because any measurement of the amount of oil
recovered during the quenching process would also likely include the
light ends that remain entrained within the coke product from the
conventional coking operation (i.e., light-ends derived from the resids
feedstock) which are typically recovered during the quenching process
in a manner analogous to steam stripping.
---------------------------------------------------------------------------
\9\ See the September 3, 1997, letter from Kyle Isakower to Max
Diaz and the January 9, 1998, letter from Richard Fortuna to Michael
Shapiro.
\10\ See January 23, 1998, letter from Paul Bailey to Michael
Shapiro.
---------------------------------------------------------------------------
One of the critical factors in estimating the oil recovery
efficiency of the quenching process is the specific gravity of the oil
contained in the hazardous secondary materials. The lighter the oil
fractions, the more oil will volatilize during the quenching process.
Here, too, there was disagreement among commenters over how the oil
contained in the secondary materials should be characterized. One
commenter stated that since crude oils have grown steadily heavier
(i.e., contain a larger percentage of higher molecular weight, higher
boiling point hydrocarbons) over time, a trend that is only expected to
continue, the oil contained in the secondary materials, especially the
wastewater treatment sludges, would be disproportionately heavy and
thus would be less and less likely to volatilize during the quenching
process. This was supported by data (gathered from listed hazardous
wastes sent to RCRA-permitted facilities) demonstrating the heavy-to-
light ratio for oil contained in the wastes. 11 In response,
the petroleum industry stated that the oil contained in the secondary
materials (particularly wastewater treatment sludges) comes from oil
that has been through some refining, and thus the trend towards heavier
crude oils will not have a corresponding effect on the oil contained in
the secondary materials. Also, industry claims that the actual data
used to support the assertion that the oil contained in the secondary
materials is predominantly heavy is not representative of the secondary
materials used in the quenching process because, prior to sending such
materials to a permitted facility for proper treatment and disposal, a
refinery will typically use other processes (e.g., centrifuging) to
aggressively extract as much oil (and water to reduce the volume of
material sent for treatment and disposal) as possible from the
materials, more so than would be the case if these materials are to be
used in the quenching process. The oil recovered by these more
aggressive recovery processes would tend to be the lighter oils,
leaving a disproportionate amount of heavy oil in the materials
analyzed. 12
---------------------------------------------------------------------------
\11\ See the January 9, 1998, letter from Richard Fortuna to
Michael Shapiro.
\12\ See the February 2, 1998, letter from John Medley to Max
Diaz.
---------------------------------------------------------------------------
Based on a considered evaluation of these conflicting comments, and
using engineering and technical judgement in lieu of data actually
demonstrating the recovery of hydrocarbon values from the secondary
materials used in the quenching process, the Agency believes that oil
(i.e., hydrocarbon value) is recovered during the quenching process and
that the efficiency of this recovery is comparable to the recovery of
light-ends during the conventional coking process. (The Agency also
notes that in the worst case scenario provided by one commenter opposed
to the exclusion, which assumed 80 percent of the oil in the secondary
material was too heavy to significantly volatilize at the temperatures
encountered during the quenching process, there was recovery of
hydrocarbon, even from the heavy oil fraction.13)
Effect of Using Hazardous Secondary Materials in the Quenching Process
on the Coke Product
---------------------------------------------------------------------------
\13\ See the January 9, 1998, letter from Richard Fortuna to
Mike Shapiro.
---------------------------------------------------------------------------
A further consideration, in spite of the hydrocarbon recovery and
contribution of energy value to the coke product, is whether the use of
the hazardous secondary materials in the quenching process actually
provides some beneficial contribution to the coke, or whether it may
degrade the coke product. Commenters opposed to allowing the use of
hazardous secondary materials in the quenching process raised two main
concerns regarding the effect on the coke product. First, these
commenters claim that the use of hazardous secondary materials in the
quenching process contributes nothing beneficial to the coke product.
These commenters dismiss the notion that the oil contained in the
secondary materials used in the quenching process contributes energy
value by stating that any energy value that may be gained is more than
negated by the additional ash content that is also introduced to the
coke product (thus, there is no net benefit to the product and instead
a net degradation of the product).14 Furthermore, as at
least one commenter noted, the ability for the coke produced using the
hazardous secondary materials in the quenching process to continue to
meet product specifications could simply be an indication that the
specifications for this low-value fuel product provide a great deal of
flexibility, rather than demonstrating that the product is not
adversely affected. Thus, the product specifications themselves would
allow for a certain amount of non-contributing hazardous secondary
materials to be added to the coke product.15
---------------------------------------------------------------------------
\14\ See the January 9, 1998, letter from Richard Fortuna to
Mike Shapiro.
\15\ See the January 9, 1998, letter from Richard Fortuna to
Mike Shapiro.
---------------------------------------------------------------------------
The second concern raised regarding the effect of the secondary
materials on the coke product is that the coke product demonstrates no
significant change in concentration of hazardous constituents due to
the simple dilution that occurs when a relatively small amount of
hazardous secondary material is mixed with a much larger volume of coke
product (approximately 100 barrels, or about 20 tons of hazardous
secondary materials are used in the quenching of 700-800 tons of coke
product). Simply stated, the lead and chromium in the secondary
materials are being diluted by combination with the much larger volume
of coke product containing low levels of lead and chromium. Since these
metals are not volatilized during the quenching process, they must
remain in the coke product. Commenters point to the insertion of lead
and chromium (which serve no purpose in the coke product) as evidence
that the use of hazardous secondary materials in the quenching process
is simply disposal of hazardous constituents. Such disposition of
unwanted and unneeded hazardous constituents, often termed ``toxics
along for the ride,'' is a prime indicia that sham recycling can be
occurring (depending largely on the extent of contamination, as well as
other case-
[[Page 42125]]
specific facts) (see U.S. v. Marine Shale Processors, 81 F.3d 1361,
1366 (5th Cir. 1996)).
In evaluating the first concern, i.e., whether the use of oil-
bearing secondary materials in the quenching process provides a
beneficial contribution to the coke product or process, the Agency
notes that the main purpose of the petroleum coking unit is to recover
hydrocarbons from the oil contained in the feedstocks for further
refining. Similarly, the main purpose of using the secondary materials
in the quenching process is the energy-efficient recovery of
hydrocarbon from the residual oil in the oil-bearing secondary
materials. Concerning the issue of net contribution to the coke product
(i.e., added energy value versus added ash content), the petroleum
industry maintains that the additional ash content is insignificant and
points to the amount of coke product produced per cycle (ranging from
about 400 to 800 tons) that would be endangered if the ash content (as
well as the VCM level) contributed during the quenching process was
sufficient to lower the value or marketability of the coke
product.16 In answer to the concern that the product
specifications for petroleum coke are too flexible to use as an
indication that the coke is unaffected by the hazardous secondary
materials, the Agency notes that coke product produced using hazardous
secondary materials in the quenching process is basically similar to
coke produced without using secondary materials in the quenching
process. Further, EPA notes that the quenching process can and does
produce anode-grade coke, the most high-valued coke with the most
stringent product coke specifications.17
---------------------------------------------------------------------------
\16\ See the September 3, 1997, letter from Kyle Isakower to
William Brandes and the January 23, 1998, letter from Paul Bailey to
Michael Shapiro.
\17\ See the September 3, 1997, letter from Kyle Isakower to
William Brandes.
---------------------------------------------------------------------------
In considering the second concern, i.e., whether the fact that the
coke product produced using secondary materials in the quenching
process continues to meet the product specifications (and, in fact,
demonstrates little change in the levels of contaminants compared with
coke produced without hazardous secondary materials) is simply a result
of dilution, the Agency acknowledges that such dilution does occur.
However, there are several other considerations. As stated earlier, the
primary product of the petroleum coking process is the hydrocarbon
fraction recovered for use as feedstock in the production of high-value
fuel products, with the coke product being a co-product of the coking
process. The Agency is convinced that such recovery occurs when oil-
bearing secondary materials are used in the quenching process. Given
that the recovered hydrocarbon is the primary product of using the
secondary materials in the quenching process, the simple fact that the
coke product (i.e., the co-product) continues to meet the applicable
product specifications and shows no appreciable increase in risk
carries more weight in the Agency's evaluation. In other words,
demonstrating hydrocarbon recovery is the key test in determining
whether the hazardous secondary materials actually serve a useful role
in the overall coking operation, rather than demonstrating a net
contribution to the coke (as opposed to no degradation of the coke).
Acknowledging that there is a potential for some degradation of the
coke product, depending on the constituent make-up of the particular
secondary materials used in the quenching process, the Agency believes
that the product specifications, and the economic consequences if those
specifications are not met, will serve to limit the use of the
quenching process to secondary materials that will not cause the coke
to exceed its specifications, and effectively limits the allowable
insertion of metals and excess high boiling point hydrocarbons.
However, in cases where there is sufficient degradation of the product
(or co-product) such that it no longer meets product specifications or
otherwise becomes unmarketable, the Agency would question the
legitimacy of using the secondary materials in the quenching process.
Similarly, if there were sharply decreased efficiency of hydrocarbon
recovery stemming from the use of the hazardous secondary materials in
the quenching process (recovery rates of, for example, less than 50
percent of the oil contained in the secondary materials, rather than
the minimum 70 percent efficiency EPA believes occurs), the Agency
would question the legitimacy of the activity. (The Agency knows of no
such cases at present.)
Taken all together, the fact that (1) the recovery efficiency of
hydrocarbons from oil contained in the secondary materials used in the
quenching process is comparable to the recovery efficiency of the
conventional coking process, (2) the use of oil-bearing hazardous
secondary materials (including RCRA listed hazardous wastes) in the
quenching process is consistent with the overall goal of the petroleum
refining industry, namely to maximize the recovery of hydrocarbon
values from the original crude oil feedstocks (and thus is akin to
ongoing processing), (3) the oil cannot be recovered from these
secondary materials by any other process customarily utilized in
petroleum refining, and (4) the coke product continues to meet product
specifications and indicates no increase in risk, the Agency concludes
that the use of oil-bearing hazardous secondary materials generated by
the refinery industry can legitimately be used in the coke quenching
process, dependent upon whether there is both hydrocarbon recovery and
no adverse effect on the coke product.
Regulatory Status of the Quenching Process
Having determined that certain oil-bearing hazardous secondary
materials can be legitimately used in the quenching process, the
question then becomes whether this activity constitutes ongoing
production and hence is excludable, or, rather that it is legitimate
hazardous waste recycling--potentially subject to regulation as a form
of hazardous waste treatment. There are several factors that could lead
to either outcome. As stated earlier, there is recovery of hydrocarbon
values from the oil-bearing secondary materials, short- and middle-
chain fractions that are condensed and sent to refining processes to
produce high-value fuel products (consistent with the overall coking
operation). In addition, there is some beneficial contribution to the
coke product in the form of carbon and higher energy values (even
though this may not be reflected by an actual increase in market
value), and the Agency also notes that the coke product continues to
meet the market-driven specifications for the product, even for high-
value anode grade coke. In addition, as with other sidestreams
generated by one process and used as feedstocks to other production
processes, this activity constitutes a link in the multi-step chain of
processing steps designed to recover as much of the hydrocarbon value
from the original crude oil feedstock as possible. Thus, there are
aspects of this activity that lead one to conclude that the oil-bearing
hazardous secondary materials used in the quenching process can be
considered, for regulatory purposes, as part of an ongoing production
process and hence classified as an activity not subject to RCRA
jurisdiction.
There are, however, several factors that were raised in comments to
argue that using the hazardous secondary materials in the quenching
process is a form of waste management, e.g.,
[[Page 42126]]
legitimate hazardous waste recycling. The oil-bearing secondary
materials are not typical of normal feedstocks to any other refining
process. Typical feedstock streams are very high in oil content (i.e.,
primarily oil), while these secondary materials contain a range of oil
concentrations that is consistently much lower than typical feedstocks
(thus resulting in a much smaller amount of oil being recovered, albeit
at an efficiency comparable to conventional coking, as discussed
above).
There are numerous statements, both written and verbal, found
within the industry's internal descriptions of the use of hazardous
secondary materials in the quenching process, that depict this activity
as an efficient means of disposing of RCRA hazardous
wastes.18 There is also anecdotal evidence of a refinery
with a coker charging another refinery without a coker to take such
oil-bearing hazardous secondary materials which are then used in the
quenching process, analogous to tipping fees or charges that a
hazardous waste recycling facility would receive from a generator in
return for a waste management activity. These issues are some of the
reasons EPA felt it was not compelled by statute to exclude these
wastes as ongoing manufacturing, and that this is a decision for EPA's
discretion.
---------------------------------------------------------------------------
\18\ See the January 9, 1998, letter from Richard Fortuna to
Mike Shapiro.
---------------------------------------------------------------------------
In considering both viewpoints, the Agency has decided that use of
hazardous secondary materials in the quenching process warrants an
exclusion from the definition of solid waste (always assuming that the
particular practice is legitimate recycling). In the Agency's view, the
primary purpose of this activity is the recovery of the remaining
hydrocarbon values in the oil-bearing secondary materials (with the
addition of carbon and energy value to the co-product coke), utilizing
the existing heat energy contained in the coke product after the
conventional coking process. The assertion, by commenters opposed to
this activity that it is questionable that the component in the
secondary material that fulfills its primary purpose (i.e., oil) could
also be a limitation on the use of the secondary material (i.e., that
too much oil would degrade the coke product itself) is not compelling.
It is not uncommon for industrial processes to have specifications on a
feedstock material that require a minimum of a certain component while
at the same time requiring that a maximum level for the same component
not be exceeded because it would degrade the quality of the product.
EPA also believes that the lead and chromium in the secondary materials
should decline with time. This is due to overall reductions in the use
of these metals throughout the refinery (e.g., leaded gasoline is no
longer produced on a wide scale and chromium-based water treatment
chemicals are no longer used in industrial cooling towers, as a result
of Clean Air Act requirements; see 40 CFR Part 63, Subpart Q). Thus,
with the exception of lead and chromium (which are expected to decrease
due to process changes), the hazardous metals found in the hazardous
secondary materials can be traced back to the metals found in the
original crude oil feedstock and so do not represent contaminants
introduced through means other than the continued processing of the
initial raw material feedstocks. EPA's traditional concern regarding
unnecessary hazardous constituents being processed and ending up in a
product is mitigated in this case because the Agency views this
activity more as the continual processing of a raw material that
contains hazardous constituents, with concentrations of these
constituents found in the feedstock streams to various refining
processes varying dependent on the point in the overall production
process. In the context of a multi-step production process, there is
much less of an element of discard of the hazardous constituents
inherent in the original raw material than there would be had these
secondary materials been generated by another industry or had the
hazardous constituents not been inherent to the original raw material.
EPA also has no evidence that the quenching process could be viewed
as part of the waste management problem, part of the jurisdictional
tests articulated in AMC I and II. As discussed earlier, there is no
significant evidence of degradation of coke product quality, and
indeed, coke produced with and without using secondary materials in the
quenching process are largely indistinguishable from the standpoint of
concentrations of hazardous constituents.19 Finally, again,
EPA believes that the recovery of hydrocarbon from the oil-bearing
secondary materials in the quenching process is consistent with the
overall petroleum refining process the coking operation in particular,
i.e., the recovery of hydrocarbons for the production of high-value
fuel products. This goal, in turn, is consistent with the RCRA
objective to encourage safe types of recycling (see RCRA section
1003(a)(6)). Therefore, the Agency is providing a conditional exclusion
for oil-bearing hazardous secondary materials that are inserted into
the coker, based on the assumption that, whether inserted along with
normal feedstock (i.e., resids) or used in the quenching process,
hydrocarbons are recovered for further refining and there is no
degradation of the coke product.
---------------------------------------------------------------------------
\19\ See the January 23, 1998, letter from Paul Bailey to
Michael Shapiro.
---------------------------------------------------------------------------
Conditions for the Exclusion
As stated at proposal (60 FR at 57754-57755), the exclusion
applicable to oil-bearing hazardous secondary materials destined for
insertion into the petroleum refinery, including the coker (and the
quenching process), is conditioned on there being no land placement and
no speculative accumulation, ensuring that these oil-bearing hazardous
secondary materials do not become part of the waste disposal problem.
EPA reiterates its belief, presented in the proposal, that the
management of these secondary materials prior to insertion into the
refinery will not pose a risk to human health and the environment, and
that the American National Standard Institute (ANSI) standards for the
design, construction, operation, maintenance, and inspection of
petroleum terminal and tank facilities are sufficient to ensure that
such materials will be managed in an environmentally protective manner.
The Agency also notes that the exclusion being promulgated today is
only for those oil-bearing hazardous secondary materials that are
actually used in a refining process, including the quenching process of
a petroleum coker. Hazardous secondary materials that are released and
not immediately recovered and used in a refining process would not be
excluded, and thus would be subject to Subtitle C regulation as
hazardous wastes that have been disposed.20
---------------------------------------------------------------------------
\20\ The Agency notes that today's rulemaking is not intended to
affect the applicability of existing regulatory exclusions in
Sec. 261.2(c)(2) and (3) regarding the reclamation of off-
specification or spilled commercial chemical products listed in
Sec. 261.33, or that otherwise exhibit a hazardous characteristic
(50 FR 14219; April 11, 1985).
---------------------------------------------------------------------------
The Agency is also requiring that the materials excluded under this
provision of today's rule be returned directly to a refinery for
insertion. While this is not an issue if materials are recycled onsite,
EPA has concerns (as did some commenters) about situations where these
materials are generated at one refinery for insertion into another, but
are not directly sent and instead are sent to an intermediate non-
refinery facility for processing. EPA does not think it
[[Page 42127]]
unreasonable to assume that these materials should either be located at
the generating refinery, at the receiving refinery, or are otherwise in
transit between the two; this is consistent with the underlying
argument that this is ongoing production within the petroleum refining
sector.
The Agency is maintaining the condition that only those oil-bearing
secondary materials that result in a coke product that does not exhibit
a characteristic of hazardous waste be subject to the exclusion. This
condition mirrors the statutory provision stating that petroleum coke
produced from petroleum industry hazardous wastes is not subject to
Subtitle C regulation provided the coke does not exhibit a
characteristic of hazardous waste (see RCRA section 3004(q)(2)(A)).
This condition (coupled with the industry's own product specifications)
will serve to ensure that the coke product does not degrade such that
the secondary materials used in producing the coke will become a part
of the waste disposal problem. As a result of this condition and the
fact that this exclusion is limited to refinery wastes, today's
exclusion in Sec. 261.4(a)(12) supersedes the existing exemption in
Sec. 261.6(a)(3)(v); therefore, the regulations are being amended to
remove Sec. 261.6(a)(3)(v).
The Agency considered, as suggested in several comments, setting a
minimum oil content to define the scope of ``oil-bearing secondary
materials'' that are excluded when used in the quenching process, or to
require a demonstration of hydrocarbons actually being recovered from
the excluded secondary materials that is comparable to oil recovery in
the conventional coking process. The Agency rejected limiting the
exclusion based on a set minimum oil content or a recovery efficiency
requirement for several reasons. As discussed above, the quenching
process represents the final, and last possible process in which to
recover hydrocarbon from the original crude oil feedstock. The refinery
processes and operating procedures are designed to separate and process
into products as much hydrocarbon as possible from the crude oil
feedstock; in other words, to prevent as much oil from making its way
into these secondary materials as possible. The oil that does make its
way into these secondary materials is generally considered unavoidable
and inevitable, or, in some cases, too much oil in these secondary
materials is evidence of a problem with some aspect of the overall
refining process (which helps to explain the wide range of oil contents
in these materials). Thus, it would be counter to the overall
efficiency of the petroleum refining process to require a minimum oil
content in the secondary materials. Conversely, the Agency believes it
is fundamental to this exclusion that there actually be oil recovered
for further refining when these oil-bearing hazardous secondary
materials are used in the quenching process. To the extent there is no
recovery, or drastically inefficient recovery, the operation could be a
type of sham recycling, as discussed earlier.
Also, the Agency believes that, in this case, a minimum oil content
condition would do little to ensure that only those secondary materials
from which oil can actually be recovered would be excluded; in other
words, the Agency does not believe that setting a minimum oil content
would ensure that secondary materials are legitimately being used in
the quenching process. Since most of the secondary materials in
question result from wastewater treatment, a minimum oil content
requirement would only serve to encourage a refinery to operate the
refinery wastewater treatment process less efficiently to ensure that
these secondary materials contain the minimum oil content and thus
avail themselves of an exclusion.
As for requiring a demonstration of oil recovery efficiency
comparable to the conventional coking process, the Agency concluded
that the normal operating practices and conditions (e.g., temperature)
inherent to the quenching process will result in a comparable oil
recovery efficiency. While there may be fluctuations in the actual
volume of oil recovered (due to the fluctuations in the oil content of
the secondary materials as well as the ratio of heavy-to-light oil in
the secondary materials), the quenching process, when properly
operated, is such that there will be oil recovered from oil-bearing
hazardous secondary materials due to the high temperatures inherent in
the process. Therefore, requiring an actual demonstration of recovery
efficiency would be unnecessarily burdensome unless there is a question
regarding a site-specific coke quenching process or the hazardous
secondary materials being used. Therefore, the exclusion for refinery-
generated, oil-bearing hazardous secondary materials being legitimately
recycled into the petroleum refining process, including in the coke-
quenching process, is conditioned only on these materials being managed
such that there is no land placement and no speculative accumulation,
and that the coke product produced not exhibit a characteristic of
hazardous waste.
Materials Subject to the Exclusion
At proposal, the Agency proposed to exclude oil-bearing hazardous
secondary materials that are generated within the broad petroleum
industry (covering SIC codes 1311, 1321, 1381, 1382, 1389, 2911, 4612,
4613, 4922, 4923, 4789, 5171, and 5172--which comprise petroleum
refining, marketing, transportation, exploration, and production) and
inserted in the petroleum refining process, including in the coker. As
discussed earlier in today's preamble, the exclusion being promulgated
today is limited to only those oil-bearing hazardous secondary
materials that are generated within the petroleum refining sector (SIC
code 2911). To conform with this limitation, EPA is retaining (with
some clarification) the existing exclusion for recovered oil from the
broader petroleum industry. (EPA is also excluding petrochemical
recovered oil from certain petrochemical facilities, which is a related
but different exclusion discussed elsewhere in today's rule.) In the
context of oil-bearing hazardous secondary materials being used in the
quenching process, limiting the exclusion to the petroleum refining
sector is entirely consistent with the information evaluated in making
this determination (i.e., data representing the materials currently
used in the quenching process, namely F037, F038, and K048-K052). As
discussed above, the exclusion for oil-bearing hazardous secondary
materials used in the quenching process was not made on a strict
jurisdictional basis. The types of secondary materials, their
constituent components, and the fact that the coke product remains
basically unchanged when such secondary materials are used were all
factors in EPA's determination. The fact that the Agency only evaluated
oil-bearing secondary materials that were generated by the refining
sector in its determination is sufficient reason to limit the exclusion
to refinery-generated secondary materials.
However, a further reason relates to the concept that oil-bearing
secondary materials that are generated by the refining process and
continue to be processed in the coker (by use in the quenching process)
is more akin to an ongoing production process than would be the case
for secondary materials generated outside the refining sector of the
petroleum industry. The Agency maintains that the quenching process is
an ancillary activity that is somewhat removed from the overall
production process; however, the fact that the secondary materials are
generated and
[[Page 42128]]
used in another production process (i.e., the overall coking operation)
within the same industry, imparts a closer association with the concept
of an ongoing production process (see AMC I) than would be the case for
secondary materials generated by a different industrial sector. The
Agency has no information on which to base a finding that the use of
oil-bearing hazardous secondary materials originating in a non-refinery
sector of the petroleum industry in the coke quenching process would be
anything other than the management of wastes (e.g., hazardous waste
recycling) from that non-refinery sector.
In one sense, the exclusion for recovered oil (as opposed to ``oil-
bearing secondary materials''), which spans the scope of the broad
petroleum industry, reflects the Agency's assessment that only those
hazardous secondary materials that are comparable to normal feedstocks
(i.e., oil) used in typical production processes should be excluded
from RCRA without attention to how they are processed. Oil-bearing
secondary materials (as opposed to ``recovered oil'') originating from
a non-refinery sector have the potential to be more waste-like (i.e.,
they are not clearly ``oil'' and also may contain types or quantities
of toxic constituents that have not been evaluated, especially if their
ultimate use is in the quenching process) and thus do not warrant an
exclusion. Therefore, the Agency is today promulgating an exclusion for
(1) secondary materials that are similar to normal refining feedstocks,
even if generated by a non-refinery petroleum industry sector (i.e.,
recovered oil) and (2) secondary materials that are both generated by
and used in any refinery production process, including the coking
operation (i.e., refinery-generated oil-bearing hazardous secondary
materials).
The Agency notes, however, that non-refinery generated oil-bearing
secondary materials that are used in the quenching process (i.e.,
hazardous wastes) may nevertheless be legitimately recycled by use in
the quenching process, depending on there being oil recovered during
the quenching process and no adverse impact on the coke product. The
oil recovered during the coking operation (including both conventional
coking and the quenching process) is excluded from the definition of
solid waste under 40 CFR 261.4(a)(12). The coke product produced from
such hazardous wastes, however, would be subject to hazardous waste
fuel regulations. This does not represent a change from current
requirements, because the current regulatory exemption for coke
produced using hazardous waste (superseded by today's exclusion for
refinery waste being recycled) does not apply to coke produced using
anything but refinery-generated waste.
Status of Residuals from Processing or Recycling Excluded Oil-
Bearing Secondary Materials
EPA received comments stating that the proposed rule did not
clarify the status of residuals generated from the processing and
recycling of excluded oil-bearing hazardous secondary
materials.21 Specifically, certain oil-bearing hazardous
secondary materials generated at petroleum refineries are listed
hazardous wastes if they are discarded instead of recycled as described
in today's rule. However, the Agency is aware that these materials may
be processed in various ways prior to insertion into the petroleum
refinery, depending upon the nature of the oil-bearing material and the
intended point of insertion into the refinery. Some of these processing
steps may result in residuals that are not suitable for insertion,
again based upon the choices available to the refinery. If these
residuals are to be discarded, they are clearly solid wastes and would
not retain their original hazardous waste listing because of the
exclusion. The hazardous waste characteristics may or may not capture
these materials, and therefore they could be disposed of outside the
Subtitle C system. The Agency then became concerned about situations
where, for example, a listed waste was generated and only minimally
processed to recover oil for insertion into the refining process,
leaving behind a largely unchanged residual that was to be discarded
but was no longer defined as listed waste. The Agency agreed that this
was a potential problem with the exclusion, and a subsequent request
for comment letter was sent to interested parties on October 1, 1997.
EPA requested comment on whether the interested parties viewed this
situation as a potential loophole, and what, if anything, might be done
to remedy it. Responses to EPA's request were somewhat mixed. Some
commenters did not believe the loophole was a realistic construction of
the effect of the exclusion, while others agreed that it was indeed
problematic and needed to be addressed. After reviewing the information
submitted by commenters, the Agency has decided that it would be an
undesirable outcome if listed wastes were only marginally processed,
generating residuals that were not recycled and escaped regulation.
Therefore, the Agency has slightly modified the existing hazardous
waste listing description in 40 CFR 261.31 for the F037 waste, to
include in the listing description any residuals generated from
recycling or processing oil-bearing secondary materials that (1) would
have otherwise met a listing description when originally generated, and
(2) are disposed of or intended for disposal.
---------------------------------------------------------------------------
\21\ Comment PRLP-0054, ARCO Products Company.
---------------------------------------------------------------------------
2. Recovered Oil From Associated Petrochemical Facilities
It is logical that the Agency evaluate the integrated nature of
petroleum refining and petrochemical manufacturing to further identify
oil-bearing materials that can be permissibly classified as part of
``ongoing manufacturing'' within the petroleum industry, and that are
not part of the waste disposal problem. In proposing the exclusion for
oil-bearing materials from petrochemical operations which are returned
to refining, the Agency had two important considerations. The first
consideration was to encourage the recovery of a valuable resource and
reduce regulatory uncertainties in cases where oil from petrochemical
facilities is returned to petroleum refineries, specifically in
situations where the refineries generally provide the raw materials
(refinery products) to the organic chemical manufacturing facilities.
The second was to consider whether or not these hydrocarbon streams
have accumulated toxic constituents through the various chemical
manufacturing processes, constituents that have no value to the
petroleum refinery, are different from the constituents typically
encountered in a petroleum refinery, and may be inadequately managed
through this activity. Given the large and complex nature of the
organic chemical manufacturing industry, this was not a straightforward
undertaking. Accordingly, the Agency proceeded cautiously, engaging in
discussions with representatives from both the chemical manufacturing
and petroleum refining industries.22 As discussed at
proposal, the Agency agreed with industry arguments indicating that
because significant volumes of materials composed almost exclusively of
oil from petrochemical facilities are being directed to various
petroleum refining processes, careful controls were in place
[[Page 42129]]
as a result of concerns about operational upsets and product quality.
(See 60 FR at 57756). For example, representatives from the petroleum
industry have stated that they have significant concerns about the
presence of organic chlorides in their process units due to damage from
corrosivity. In addition, comments submitted by the chemical
manufacturing industry describe ``feedstock quality management
programs,'' whereby the quality of petrochemical recovered oil is
routinely evaluated and its contribution to refinery product
performance determines its acceptability and value. One commenter, an
organic chemical manufacturer, stated that due to the critical nature
of refinery finished product specifications, all sources of
hydrocarbons to a petroleum refinery are assessed to ensure their
suitability. This ``suitability'' of petrochemical recovered oil is
assessed either through process knowledge or periodic analyses of
certain characteristics, including water and solids content, gum-
forming compounds, and metals. As the Agency has noted elsewhere in
today's rule, the petroleum refining process can be described as a
process of separating valuable product materials from the contaminants
inherent in the original feedstock, crude oil. Based on comments
submitted by the organic chemical manufacturing facilities that supply
these hydrocarbon streams to refineries, refinery operators cannot
simply assume that certain contaminants will be separated from
hydrocarbon feedstocks (crude oil or petrochemical recovered oil)
during the refining process without potentially causing equipment
fouling, corrosion, or problems with product quality. Further, due to
the integration between some refineries and organic chemical
manufacturers, there is a shared stake in avoiding costly shutdowns,
operational upsets, or other situations that might compromise the
overall safety and profitability of the combined facilities. It is from
this perspective that EPA began reviewing information indicating that
recovered oil from organic chemical manufacturing facilities was
acceptable to the refinery as a substitute for crude oil.
---------------------------------------------------------------------------
\22\ April 7, 1995, and July 31, 1995, letters to Steven
Silverman (EPA Office of General Counsel) and September 13, 1995
letter to Becky Daiss, from Michael W. Steinberg (Morgan, Lewis &
Bockius).
---------------------------------------------------------------------------
The Agency acknowledged in the proposed rule that this potential
exclusion was based on a ``very limited set of data'' (see 60 FR at
57756). At proposal, EPA was interested largely in how petrochemical
recovered oil compared to refinery recovered oil, in terms of the
parameters that would indicate suitability of the material for refining
(e.g., specific gravity; distillation temperature range; flash point;
hydrocarbon type; and sulfur, ash, and total chlorine/halogen content).
EPA also was interested in comparisons to the used oil specification,
in part because EPA has used the used oil specification in a previous
rulemaking as a surrogate for product fuel oil. Although EPA recognizes
(and two commenters independently agreed) that there are shortcomings
in using the used oil specification in the context of analyzing
petrochemical recovered oil (largely because of the purposes for which
the used oil specification was derived) the specifications for metals
and halogens are a partial surrogate for crude oil content. The Agency
also considered comparing the composition of the petrochemical
recovered oil to ``comparable fuel specifications'' currently being
developed as part of a separate Agency effort to define specifications
which would indicate when a secondary material would pose no greater
risk when burned than a fossil fuel, and therefore might be defined as
products, not wastes (see proposed rule at 61 FR at 17460, April 19,
1996). However, comparing the petrochemical recovered oil halogen data
to the comparable fuel specification did not seem appropriate because
the petrochemical recovered oil is not being burned as a fuel, but is
instead being inserted into a complex series of fuel manufacturing
processes (i.e., petroleum refining), where contaminants are removed
and hydrocarbons are converted into various fuel products.
In response to EPA's request in the proposed rule, data was
received during the comment period on samples of various hydrocarbon
streams from organic chemical manufacturing facilities (SIC code 2869)
and non-organic chemical manufacturing units (representing SIC codes
2821, 2822, 2865) located at these same facilities. EPA also received
some data representing other non co-located, intercompany chemical
manufacturing facilities. The organic chemical manufacturing data
(representing SIC code 2869) indicate that in comparison to refinery
recovered oil, the petrochemical stream was similar, and in some
aspects, ``better'' than the refinery sample (i.e., the petrochemical
recovered oil was a ``narrower cut'' requiring less refining, thus
preferable to a refiner). When comparing the submitted data
representing SIC code 2869, as well as a sample of refinery recovered
oil, to the used oil specification, both samples were well within the
specification (with the exception of flashpoint, which is not a concern
here). Regarding total halogens, the highest concentration reported in
a sample of petrochemical recovered oil was 3,400 ppm (parts per
million ) total chlorine. Irrespective of where this number fell with
regard to the used oil specification for total halogens (at 1000 ppm
EPA presumes mixing of used oil with hazardous waste has occurred; 4000
ppm is an upper limit for burning used oil without being subject to
certain requirements; see 40 CFR 279.11), the Agency was concerned
about the possible source(s) of the halogens in the petrochemical
recovered oil. Information submitted along with this data indicates
that chlorine could be introduced in small amounts to petrochemical
recovered oil due to the use of chloride-based catalysts. Subsequent
comments clarified that the use of seawater as a ``seal'' in the
petrochemical facility's oil/water separation system was the source of
the chloride in that particular sample. The commenter indicated that
although the use of seawater as a seal or barrier in the separation
tank results in some salt entering the recovered oil phase, because
this particular hydrocarbon stream is sent to a co-located petroleum
refinery to be managed along with crude oil, the chlorides are removed
in the same process that removes chlorides typically found in crude oil
(i.e., the desalter unit).23
---------------------------------------------------------------------------
\23\ December 29, 1997, and January 22, 1998, letters to David
Bussard (EPA Office of Solid Waste) from Ronald Shipley (Chemical
Manufacturers Association).
---------------------------------------------------------------------------
In summary, in the analytical data submitted in response to the
proposed rule, certain patterns in the composition of petrochemical
recovered oil were evident, including a similarity in composition to
refinery recovered oil being used as feedstock by the refinery.
Limitation on Petrochemical Recovered Oil
As mentioned earlier, part of the evaluation of whether or not
these recovered oils from petrochemical facilities are part of an
ongoing manufacturing process within the petroleum industry, and
whether the operation can be viewed as part of the waste disposal
problem, includes whether or not these materials contain toxic
constituents not normally present in typical refinery feedstocks and
intermediates. One concern that the Agency has is the possibility that
certain hazardous wastes, particularly wastes containing halogens, may
end up in the petrochemical recovered oils either through inadvertent
or intentional mixing (i.e., ``adulteration'').
[[Page 42130]]
Specifically, there are many secondary materials that the EPA has
explicitly listed as hazardous (e.g., K-wastes at 40 CFR Part 261,
Subpart D, under ``Organic Chemical Industry''). Many of these wastes
are highly-halogenated residuals, and EPA studied each of these waste
streams at the time they were listed and determined that their
management is easily capable of posing significant risks unless done
properly (viz. with exceeding care, such as is specified in the
Subtitle C regulatory standards). EPA believes that these listed wastes
are clearly distinct from the petrochemical recovered oils discussed
here, and based on the information EPA has received on the recovered
oils sent to refineries, these listed wastes are not recycled in this
manner. To ensure that this ``adulteration'' of the petrochemical
recovered oils (by mixing listed hazardous wastes) would be prohibited
under today's final rule, EPA is limiting the petrochemical recovered
oil exclusion to those recovered oils that are hazardous only because
they exhibit the characteristic of ignitability (as defined in 40 CFR
261.21) and/or toxicity for benzene (40 CFR 261.24, waste code D018).
EPA believes that petroleum refineries are able to handle hydrocarbons
that are ignitable and contain benzene, given the types of materials
that are routinely managed at these facilities; also, based on the
information EPA has received on these materials, these are likely the
only characteristics that would classify these petrochemical recovered
oils as hazardous.
Co-Located and Common Ownership
EPA proposed that the exclusion for petrochemical recovered oil
apply only where the organic chemical manufacturing facility is
``associated'' with the petroleum refinery, either by being physically
co-located or under common ownership. As mentioned previously, this was
partly due to the limited data the Agency had, but also because EPA
believed that the degree of integration between a petrochemical
facility and a petroleum refinery that occurs in co-located and/or co-
owned situations helped ensure more familiarity with each other's
manufacturing processes, composition of products and intermediates, and
administrative procedures. These attributes go beyond the strict
commercial relationship that is more typical of transactions between
buyers and sellers of various secondary materials, by-products, and
intermediates. However, the Agency has not been able to develop a
definition of ``common ownership'' that would be clear and workable for
such purposes. As part of EPA's continuing efforts to redefine solid
waste, defining common ownership (as a possible means of describing
certain intracompany transfers) also has been explored and has proven
very difficult. This is largely because of the many complex ways in
which ``ownership'' can be defined from both a financial and a legal
perspective. EPA believes that to attempt to do so here would not prove
effective. However, EPA does believe that the concept of ``co-located''
is more or less understandable and reflects physical boundaries as well
as a degree of integration that would help ensure more control by each
facility over the transfer of materials throughout the combined
facility. ``Co-located'' in today's rule means that the petroleum
refinery and the organic chemical manufacturing facility are physically
adjacent to one another, or otherwise share a common boundary. In
situations where the facilities consider themselves co-located but they
are not physically adjacent nor do they share a common boundary, the
Agency is further clarifying co-located to include facilities that have
a high degree of integration with one another, as evidenced by things
such as shared wastewater treatment systems; shared manufacturing
units; transfer of materials via dedicated piping; environmental
permits that cover both facilities; facilities that share common
emergency response equipment, procedures, and planning; etc. These
examples can be typical of physically co-located facilities, and
therefore can be used to clarify cases where for one reason or another
an integrated petrochemical and petroleum refinery do not actually
share a common boundary. Also, to better define the relationship and
degree of integration between a petroleum refinery and the co-located
petrochemical facility, the Agency is including in the definition of
``associated organic chemical manufacturing facility'' in
Sec. 261.4(a)(18) the condition that the petroleum refinery that is
receiving recovered oil from a co-located petrochemical facility also
provides the hydrocarbon feedstocks to the same co-located
petrochemical facility.
Other SIC Codes
In the proposed rule, EPA stated that it would consider broadening
the proposed exclusion to include hydrocarbon streams from certain
other chemical manufacturing facilities, including plastic materials
and resins (SIC code 2821), synthetic rubber (SIC code 2822), and
cyclic crude and intermediate producers (SIC code 2865), if sufficient
analytical data were received to support such a broadening. Much of the
data that the Agency received on recovered oil from these other SIC
codes actually represented recovered oil from process units that are
located at petrochemical facilities whose primary classification is
under SIC code 2869. In other words, many of the organic chemical
manufacturing facilities can be described as vertically integrated,
where process units classified under several SIC codes operate in an
integrated fashion. For example, an organic chemical manufacturing unit
under SIC code 2869 may produce intermediates that are then fed to a
unit classified under SIC code 2821. Both units may produce hydrocarbon
side streams that represent unreacted feedstock or other hydrocarbon
by-products (consisting almost entirely of oil), which are typically
commingled and sent to a co-located petroleum refinery for refining
along with crude oil. (Of the three co-located petrochemical facilities
for which the Agency received data on recovered oil, only one of them
was engaged in operations classified solely under SIC code 2869; the
other two facilities had units or activities from the other SIC codes
as well). The Agency reviewed analytical data on recovered oils from
specific process units representing SIC codes 2821, 2822, and 2865, and
found these to be comparable to refinery recovered oil.
Because the recovered oil from process units classified under the
SIC codes 2821, 2822, and 2865 is similar to refinery recovered oil
(where these units are part of vertically-integrated organic chemical
manufacturing facilities whose primary SIC code is 2869), the Agency is
including these materials in the scope of today's exclusion. These
materials are typically managed together and returned to the co-located
petroleum refinery together. Commenters also pointed out that limiting
the exclusion of recovered oil to the primary SIC code, at a complex
where several SIC codes are represented (and where the hydrocarbons are
similar and recycled back to the petroleum refinery together) may have
a significant impact on facilities with multiple SIC codes. Commenters
also argued that segregating recovered oil systems based on differing
SIC codes could be prohibitively expensive and may result in a
reduction in hydrocarbons returned to the refinery. The regulatory
language in today's exclusion at Sec. 261.4(a)(18) for petrochemical
recovered oil will limit the exclusion to recovered oil from
[[Page 42131]]
associated petrochemical facilities whose ``primary'' SIC code is 2869
(organic chemical manufacturing), but may also include SIC codes 2821,
2822, and 2865.
B. Modeling Approaches and Risk Assessment
Commenters provided extensive comments on various aspects of the
modeling approaches and risk assessment used in the listing
determinations. Many comments on the determinations were raised
repeatedly for various wastes. Therefore, EPA discusses the most
important risk and modeling issues below, and more specific comments
important for individual wastes are addressed in Section V.C on
Residual-Specific Comments. For complete responses to comments on these
and other issues, see the Response to Comment documents for comments on
the proposed rule and the NODA in the docket to today's rule.
1. Sampling and Analysis of Refinery Wastes
Use of the TCLP for Oily Wastes
EPA characterized the wastes through an extensive effort of waste
analysis, including analysis for constituents that leach out of the
waste using the TCLP. In the TCLP, the waste is filtered to separate
any liquid phase present, and the solids are then mixed with an aqueous
solution in order to estimate the levels of the waste constituents that
dissolve and separate into the liquid phase. The Agency's use of the
TCLP as input to groundwater modeling for landfill disposal was
challenged by several commenters as either underestimating or
overestimating the leaching of constituents from the petroleum wastes
studied, due to the oil and/or the multiple phases present in the
wastes. EPA has decided that the TCLP is appropriately used in this
rule to characterize the amount of hazardous constituents potentially
released from landfills through aqueous leaching. As discussed below,
EPA found no need to change its risk assessment because of any failure
of the TCLP due to potential problems that might arise from the
presence of oil in some wastes.
One commenter argued that the TCLP is very conservative because it
assumes that the waste is disposed of in a municipal solid waste
landfill, and disposal of potentially hazardous industrial wastes in a
municipal landfill is not a likely mismanagement scenario today. The
commenter also argued that the TCLP is a water phase model, not a
multi-phase model (multi-phase meaning wastes with high oil content
leading to release of nonaqueous as well as aqueous phases). The
commenter claims that use of the TCLP to estimate risks from oil-
bearing residuals (e.g., CSO and crude oil storage tank sediment) would
produce overestimates of potential risks.
EPA does not agree that the TCLP overestimates leaching levels for
these wastes. EPA did not assume in its quantitative risk assessment
that oily liquids elute from the landfill to groundwater, because EPA's
initial and subsequent analyses showed that oil in the wastes in
question was unlikely to migrate from a landfill containing these
wastes. Thus, EPA did not use the TCLP to predict movement of oily
liquids. While the commenter is correct in stating that the TCLP
procedure was designed, in part, to represent leaching from a municipal
landfill, the industry reported significant volumes of residuals being
disposed in precisely the type of landfill modeled by the TCLP.
Specifically, EPA examined the data collected from the 3007
Questionnaire and found that, in fact, petroleum refineries reported
146 wastes that were sent to municipal landfills (see Additional
Listing Support Analysis, 1998, in the docket for this rule).
Other commenters felt that the TCLP may underestimate the
leachability of constituents from the refinery wastes due to high oil
content. These commenters pointed to an EPA report presented in past
rulemakings (e.g., the listing of F037/F038 refinery wastes, November
2, 1990, 55 FR 46376), which indicated that the TCLP may underestimate
leachate concentrations because of difficulties in the TCLP procedure
associated with filtering oily wastes, such that any constituents in
the oily fraction in the waste are not properly evaluated. The
commenters believed that EPA should use alternative procedures for oily
waste, specifically the Oily Waste Extraction Procedure (OWEP) rather
than the TCLP.
EPA disagrees with these comments. First, the report cited by the
commenters discusses difficulties in filtering multi-phasic oily wastes
(Evaluation and Modification of Method 1311 for Determining the Release
Potential of Difficult-to-Filter Wastes, April 1990). Multi-phasic
wastes are wastes with readily separable oil, solid, and possibly
aqueous portions. EPA's lab results show that the wastes under study in
this rule did not exhibit the filtration difficulties EPA has found
with other, more problematic, oily wastes. The wastes studied were not
multiple phases, heterogeneous, or difficult to filter. While EPA
measured levels of ``total oil and grease'' (TOG) that appeared high
for some wastes (e.g., up to 25 percent for crude oil storage tank
sediment), the Agency stresses that the TOG method measures all
extractable organic material, some of which are not likely to migrate
out of the waste, such as waxes, greases, and other large molecular
weight substances. The TOG method does not measure, in any sense,
``free'' oil (i.e., oil that might migrate from the waste as a separate
phase). Furthermore, the EPA report cited by the commenter concluded
that the TCLP method was adequate, even for some ``oily'' wastes,
provided the wastes could be filtered. EPA did not encounter the types
of problems described in previous listings during the present
rulemaking.
Second, the Agency does not believe that the use of the OWEP method
is necessarily more appropriate for the wastes under consideration. The
OWEP method was designed to measure the aqueous mobility of the metals
(not organics) present in wastes, and uses a strong solvent to remove
the organic phase prior to leaching with the aqueous leachate used in
the TCLP. This may significantly alter the original sample matrix and
affect the leaching results, and the Agency recognizes that this
aggressive method may not be fully representative of possible leaching
from a landfill. Despite these concerns, EPA performed additional
analysis of archived samples using the OWEP to fully respond to the
comment by examining any differences in metals mobility between the
TCLP and the OWEP. The results of this analysis were presented in the
NODA. Based on the results of this analysis, EPA found that metal
leachate results were similar between the two tests. Therefore, EPA
concluded that oil content (as measured by TOG) does not appear to
impact the mobility of metals in the wastes under study.
Commenters on the NODA OWEP analysis argued that the results showed
some increase in the mobility of several metals in the wastes, and
argued leachable levels of arsenic, chromium, and lead are higher in
some of the OWEP samples. However, the same commenters also questioned
the validity of the OWEP reanalysis because three years had elapsed
between the TCLP and OWEP analyses and pointed out that the reanalysis
was not useful since the detection levels were higher for the TCLP
analysis.
EPA disagrees that any measurable differences, of which there were
few, in the OWEP/TCLP results are dramatic or meaningful. Overall, the
OWEP results are consistent with the original TCLP
[[Page 42132]]
data; only 14 out of 189 OWEP values were greater than the original
TCLP concentrations. Moreover, 8 of the 14 higher OWEP values were
associated with residuals that contained less than one percent oil and
grease, thus indicating oil and grease content is not a significant
factor. In fact, the variability within each waste category is greater
than the variability between OWEP and TCLP results. Thus, any
differences are more likely due to sample composition variability
rather than the leaching technique. Furthermore, if oil content were
truly interfering with the TCLP analysis, one would expect the wastes
with higher oil content to show correspondingly greater leaching with
the OWEP, but there is no such trend in the data (see NODA Response to
Comment Document, 1998, Section I.C.1, for more detailed discussion of
the OWEP data). While there are limitations in the OWEP data, the lack
of any significant differences in the data sets that can be compared
indicates that the use of the TCLP did not underestimate the leaching
of the metals of concern.
In response to the commenters' concerns over the use of the TCLP
for measuring the mobility of organics in these refinery wastes, EPA
examined the analytical data for the wastes under study to see if oil
content (as measured by TOG) significantly affected the leachability of
a key organic constituent (benzene) and presented the results in the
NODA. For the 27 samples for which the leaching efficiency of benzene
could be calculated, the average efficiency was 53 percent, i.e., 53
percent of the total mass of benzene contained in the residual was
extracted into the aqueous phase. This efficiency is governed by the
solubility of benzene in water, as well as benzene's affinity for the
specific sample matrix. In any case, while the leaching efficiency
varied somewhat from sample to sample, the leaching rate was fairly
consistent regardless of whether the waste contained higher or lower
total oil; the average leaching efficiency for the six of the 27
samples which had TOG above 1 percent (samples of crude oil tank and
CSO tank sediment) was also 53 percent.
Comments on the NODA suggested using the average leaching
efficiency (53 percent) for modeling the key constituent benzene for
all waste samples analyzed by EPA, regardless of the actual TCLP
results for each waste. EPA disagrees with the suggestion to use the
simple average TCLP leaching efficiency for all wastes studied, because
this would ignore important waste-specific information. This approach
would overestimate benzene levels for some waste and underestimate
levels for others. Leaching results are dependent on the specific
matrix, and EPA believes that the actual TCLP result is a better
indicator of the potential mobility rather than an average for all
wastes studied. The most important point to draw from EPA's evaluation
of leaching efficiency for benzene is that these results indicate the
TCLP mobility of benzene is not greatly affected by the oil content in
these particular wastes.
Comments on the data presented in the NODA also argued that EPA
should evaluate TCLP leaching efficiency for constituents other than
benzene, in particular for polycyclic aromatic hydrocarbons (PAHs). The
commenters were concerned the oil content and free oil present in some
wastes (CSO and crude oil storage tank sediment) would facilitate
leaching of PAHs.
EPA disagrees that these constituents, including benzene, will be
more mobile due to free oil in the wastes under study, because the
existing data show ``free'' oil is not present. EPA evaluated the
leaching potential of benzene because this compound was found in
various wastes and was a key constituent in the risk analyses due to
its high toxicity and relative mobility. However, to respond to the
comment, the Agency further evaluated the leaching potential of four
additional constituents (xylenes, naphthalene, methyl phenol, and
phenanthrene). These results indicate that there is no significant
discernable trend with respect to lower leaching values associated with
higher oil and grease content (see data presented in Tables 5 through 8
in the NODA Response to Comment Document, 1998, in the docket for
today's notice). The constituents generally leached in similar
proportions for all residual types. It is not possible to calculate
extraction efficiencies for most PAHs because these constituents were
generally not detected in the TCLP extract due to their very low
solubility in water. In any case, EPA notes that the two wastes with
the higher measured TOG and PAH levels (CSO and crude oil storage tank
sediments) are being listed as hazardous waste, thus largely addressing
this concern.
Co-Solvency Effects
Some commenters felt that the TCLP is inappropriate because it
measures only the movement of contaminants that are dissolved in the
liquid TCLP phase into the groundwater, and thus fails to consider the
``co-solvency'' effects of oil and other compounds in the landfill.
Such effects, they argue, would facilitate release and transport of
constituents beyond that predicted by the TCLP, because of organic
phases separating from wastes. The commenters offered no way to account
for this in the modeling, but indicated this would increase risks.
While the commenters' concerns are theoretically possible, EPA has
no evidence that the co-solvency effect is significant in this case. To
respond to the potential for co-solvency effects due to disposal of
oily waste in landfills, EPA examined the only available data that
provides any detailed characterization of potentially co-disposed
wastes-data from the 3007 Questionnaire for the refinery wastes under
study. Thus, EPA examined the TOG data available from the 3007
Questionnaire for the refinery wastes that were reported to go to
landfills. As presented in the NODA, this analysis showed that few
wastes with higher TOG levels (i.e., >10 percent) were sent to
landfills; of the 168 wastes with TOG data, only 14 had reported TOG
levels at 10 percent or above.
Comments on the NODA analysis argued that the data set was limited
because most samples landfilled did not have TOG data, especially those
that would have higher oil content (e.g., crude oil tank sediment).
Further, commenters noted that some of the larger volumes sent to
landfills had significant TOG levels.
EPA disagrees. While the data set is limited, the data available
clearly indicate that refinery wastes with relatively high oil content
are not typically sent to landfills. In response to the comment that
larger volumes sent to landfills had significant TOG levels, EPA
estimated volume-weighted average TOG levels for the wastes with TOG
data that were sent to on-site and off-site nonhazardous landfills, and
found that these values were relatively low, i.e., less than 1 percent
for on-site landfills and about 3 percent for off-site landfills. These
weighted averages represent the TOG if all of these wastes were sent to
the same hypothetical on-site or off-site landfill. EPA notes that this
analysis of wastes sent to landfills did not consider the impact due to
listing the wastes with the highest oil content (i.e., CSO and crude
oil storage tank sediments) as hazardous under RCRA. After listing,
neither waste can go to such a landfill and would no longer contribute
to any purported co-solvency effects. Finally, as discussed above in
response to comments on the TCLP method, even those wastes with higher
TOG levels did not contain observable amounts of free oil, which might
cause co-solvency. Therefore, EPA believes that co-solvency effects
[[Page 42133]]
due to oil content of the wastes under study are not likely to be
significant.
One commenter also argued that other compounds in wastes other than
those under study may lead to co-solvency effects in landfills and
provided specific refinery examples of codisposal of individual waste
streams in 1992 and Toxic Release Inventory (TRI) data to show
potential co-solvency effects.
EPA disagrees with the commenter's approach to using the TRI
database to calculate co-solvency effects at refineries. First, EPA
notes that the TRI reporting form specifies that ``quantities reported
on the form should . . . not reflect the total quantity of waste or
constituents of the waste that are not subject to reporting
requirements.'' In other words, the reported quantities are the mass
loadings of the chemical components in land-disposed wastes and do not
reflect the total quantity of the waste itself. Since these chemicals
were managed in on-site Subtitle D landfills, they must have been
components of wastes that did not exceed the TC criteria, i.e., in the
part per billion (ppb) range. The ppb concentration range was confirmed
by dividing the TRI loadings by the total waste quantity disposed in
the on-site units identified by the commenter in 1992 as reported in
the 3007 Questionnaire. Therefore, since these ``solvent-type''
chemicals would be only a very small component of the waste, their co-
solvency properties would be insignificant.
Laboratory and Field Methods
Two commenters claimed that EPA's lab and field methods were
deficient. Specifically, they believed that EPA violated basic sampling
protocols by allowing samples to air dry prior to collection. The
commenter specifically pointed out examples of CSO sediment with lower
volatile organic levels than in other samples and examples of unleaded
tank sediment with lower benzene concentrations than in other samples.
Based on these flaws, both the total and leachable levels of volatile
organics (e.g., benzene) were underestimated by EPA, according to the
commenter. One commenter also argued that, by compositing samples, EPA
may have lost substantial amounts of volatile compounds and that the
background document does not reveal whether careful procedures were
followed.
The commenter misunderstood EPA's sampling descriptions which
described the refineries' practices of air drying of storage tanks
generating the cited wastes. This is a standard operating procedure
designed to comply with basic occupational safety practices, so that
refinery personnel can enter tanks for cleaning and inspection. In no
case did EPA allow for additional air drying. EPA believes that the
samples are representative of residuals generated throughout the
industry. In response to the commenter's comparison of detected benzene
levels among three gasoline tank samples, the Agency's entire sampling
data set demonstrates a wide concentration range for several wastes.
EPA maintains that this variability is normal, and the Agency is
neither surprised nor concerned with the range of benzene levels
detected in the waste samples mentioned by the commenter. Finally,
concerning the low levels of benzene in the CSO samples, EPA disagrees
with the commenter that benzene levels vary significantly across these
samples. Data in the proposed rule background documents show that
benzene was only detected in one of four samples at a level near the
quantification limit. The levels in the other three samples were below
the quantification limit. This means that the benzene levels were very
low (at or below the quantification level), and thus the data do not in
any sense show that there is significant variability.
Field compositing procedures, when necessary, were performed for
the non-volatile analytes only. EPA did not composite samples for
volatile analyses, because the act of mixing the samples may lead to
loss of volatiles by evaporation. The sampling and analysis protocols
used were consistent with EPA's analytical guidance and were documented
in Sampling and Analysis Plans. Careful procedures were followed in
sampling conducted for volatile analyses and loss of volatiles was
minimized.
The commenters also felt that EPA did not correctly sample CSO
sediment or HF alkylation sludge. The commenters stated that the
practice of mixing CSO sediment with cement kiln dust (CKD) prior to
sampling misrepresented the liquid content of the CSO sediment and EPA
should not have dewatered HF alkylation sludges.
In response, EPA notes that it collected samples of such wastes
that were available after tank cleanout, and in this specific case, it
had been mixed with CKD. This was done by the facility prior to
landfilling of the waste. While this treatment may have altered some
properties of this sample, the oil content (16 percent TOG) was
relatively low, compared to the other three samples of CSO sediment
collected by EPA (see Table 3.1.18 in the Listing Background Document,
1995). Even if the Agency discounted entirely the analytical results
for the one sample mixed with CKD, it would not impact the risk
assessment significantly, because this would only raise average levels
of some critical PAHs slightly (approximately 10-20 percent). In any
case, EPA is listing this waste, so inclusion of this sample had no
material impact on EPA's final decision.
HF alkylation sludge dewatering is conducted routinely by
refineries, and EPA collected most samples following this step. In this
case EPA believes this waste form reflects the way the waste is
disposed in landfills. EPA did take one sample of HF alkylation sludge
directly from the neutralization tank and dewatered it in the
laboratory to better simulate the characteristics of the waste as it
would actually be generated.
2. Waste Management Assumptions
EPA described how the Agency selected waste management scenarios
for risk analysis in the proposed rule, and requested comments on its
choice of plausible management scenarios. Some commenters wrote to
support the common sense approach the Agency used in basing listing
determinations on plausible management practices. These commenters
stated EPA's decisions were based on current management practices and
believed EPA obtained accurate and relevant data on the residuals and
management practices through site visits and the 3007 Questionnaire.
However, two other commenters suggested the Agency should evaluate
risks from other waste management practices. These practices included
waste management in surface impoundments, use as on-site cover for
landfill or LTUs, use as road bed material, and storage in a pile.
EPA does not agree that these other management practices merit
further modeling. As EPA stated in the proposed rule, while some of
these practices were reported for several different wastes, they
typically involved small volumes or very few generators, and are not
expected to present significant risk. The information collected by EPA
shows that the vast majority of the waste volume that was disposed on
the land went to landfills and LTUs, and the Agency focused its
modeling efforts on these scenarios.
The commenter specifically cited management of several wastes in
surface impoundments (spent caustic, HF alkylation sludge, off-
specification product and fines). However, EPA does not believe these
are significant as described in the sections on individual wastes
(Section V.C). In general, surface impoundments at refineries are an
integral part of the wastewater treatment
[[Page 42134]]
system, and EPA did not typically evaluate this system in detail for
the reasons noted in the proposed rule. Briefly, risks from such
treatment are unlikely to be of concern because: (1) treatment is
already regulated under the National Pollutant Discharge Elimination
System (NPDES) and air programs; (2) primary sludges generated from
wastewater treatment are already regulated as hazardous waste (K048,
K051, F037, F038); (3) volumes of the discharged residuals under
evaluation are relatively small in comparison to the volumes typically
treated; (4) the wastewater treatment systems are designed to treat
refinery wastes effectively. Furthermore, in some cases units receiving
the waste were not, in fact, surface impoundments, but tanks (e.g., HF
alkylation sludges), or other concrete-lined units used as part of
refinery processes (e.g., coke drilling pads for off-specification
product and fines). See Section V.C for the specific wastes in question
for further discussion, and Section V.D on the headworks exemption for
other analyses related to wastewater treatment systems.
Two commenters argued that the use of crude oil tank sediment and
CSO tank sediment as landfill cover or on-site road material should be
evaluated. One commenter stated that EPA's own preliminary assessments
for uncovered landfills show that use of these wastes as a landfill
cover or for on-site road material poses high cancer risks for
subsistence farmers and home gardeners and high risks from mercury
exposure for subsistence fishers. Finally, according to the commenter,
it is incorrect to assume that EPA's modeling of LTUs would account for
risks posed by road spreading or other uses constituting disposal.
The Agency disagrees that these scenarios were not adequately
considered, and the Agency does not believe that they would present
significant risk. These practices were exceedingly rare, e.g., the one
refinery which managed its crude oil tank sediment as ``cover for on-
site landfill'' in 1992 no longer uses that landfill. In addition, the
risks for crude oil tank sediment cited by the commenter were based on
bounding levels, and resulted from a preliminary screening analysis
designed to overestimate possible risks for landfills. Such bounding
estimates use worst-case assumptions for all sensitive parameters to
screen out exposures of little concern, and to identify what pathways
require further analysis. Furthermore, the apparent risks in the
bounding analysis were based on incorrect biotransfer factors (used in
beef, dairy, and plant indirect paths), which EPA has since determined
to overestimate worst-case risks by at least two orders of magnitude.
Likewise, the apparent problem from mercury was also traced to an error
in units for the bioaccumulation factor used and when corrected mercury
does not present any significant risk in these wastes. Thus, EPA
believes that the bounding analysis was flawed and grossly
overestimated risks. Similarly for CSO sediment, EPA also notes that
only two refineries reported using CSO sediment in road bed material in
1992. EPA believes that the modeled land treatment conditions are
conservative surrogates for road spreading because: (1) The volumes and
areas assessed for land treatment greatly exceed the reported road
spread volumes and areas, (2) road spreading usually involves mixing
with gravel, asphalt, dirt, etc., thereby diluting toxicants below that
represented by the wastes modeled for land treatment and reducing risk;
and (3) road spreading creates a stable road base, which is compacted
and then covered by additional fill, aggregate, or pavement, making
material less apt to wash away, erode, leach, or enter non-groundwater
pathways than material managed by land treatment. Finally, the issue is
moot because the two wastes specifically cited by the commenters (crude
oil and CSO tank sediments) are being listed, thereby preventing these
rare practices in any case.
One commenter stated that the Agency did not properly evaluate the
storage of wastes such as off-specification products and fines (i.e.,
coke-derived fines) in piles. The Agency's response to this issue is
given in Section V.C for the specific waste in question. EPA evaluated
each waste being studied to determine whether waste was being generated
frequently enough to pose a potentially significant risk, and if so,
whether it was appropriate to model interim storage (e.g., tanks,
containers, piles). In most cases, the exposure risks of most concern
are associated with long-term final disposal, and short-term storage
was not judged to pose significant potential risk. Many residuals are
generated infrequently, e.g., sediments from tanks are cleaned out
about every 10 years. EPA did model interim storage of certain wastes
that were generated more frequently when appropriate (i.e., spent
caustic, sulfur complex sludge).
Two commenters stated that by modeling management practices and
volumes based only on what occurred at the time of EPA's survey in
1992, EPA substantially understated risk and does not reflect the
potential for waste management volumes and practices that may occur in
the future. They argued the modeled volumes and practices are ``forever
fixed'' and merely reflect a snapshot in time.
EPA does not agree that the volumes and practices used in modeling
understate risks. Based on the economic factors affecting the refining
industry and practices observed during the Agency's field
investigation, 1992 was a typical year for refinery operations. As
described in the annual report issued by the Department of Energy (DOE/
EIA Petroleum Supply Annual 1992, Volume 1; May 1993), in 1992, the
national economy was not in extremis, capacity rates were high, and
plant closings and openings were within normal ranges. Furthermore, the
DOE report for 1995 shows economic and production trends for crude oil
and petroleum products. While prices for petroleum products and crude
oil varied from 1985 to 1995, no unusual spikes or dips occurred during
this time, and product production remained fairly constant over this
time period.
In addition, EPA reviewed API's Generation and Management of
Residual Materials, 1992-1993 Appendix C, which provides trends of
waste generation from 1987-1993. In general, 1992 was representative
when comparing waste generation and management for the API waste
categories and the residuals under review. Only hydroprocessing
catalysts showed a slight increase in production that year possibly due
to the new low-sulfur diesel regulations. In developing reasonable
management scenarios for subsequent risk assessment modeling, EPA
considered some potential shifts in management practices. These
considerations are discussed in the context of each specific waste (see
Section V.C). For the remaining residuals, EPA considered the industry
to be stable, and thus assumed that 1992 provided a reasonable picture
of the petroleum refining industry's practices. EPA's approach was not
``forever fixed'', but used 1992 as a reasonable starting place for
assessing the industry's waste generation and management practices.
Finally, EPA notes that its survey of refineries was a complete
census of the industry, and gathered information from all active
petroleum refineries in the United States. It is reasonable for the
Agency to conclude that the large amount of information gathered in its
1992 survey of petroleum refineries related to waste generation,
management, and disposal practices is representative of such practices
in any year. While individual refineries may change practices in any
given year, the overall pattern of these practices,
[[Page 42135]]
including waste volumes and the potential environmental risks posed,
are unlikely to change significantly for the industry as a whole.
Therefore, EPA has no reason to believe that 1992 was not a
representative year.
The commenter also stated that waste volumes modeled in the NODA
risk assessment were inappropriate because the individual waste volumes
modeled for land treatment were typically much smaller than modeled for
landfilling, even though there is no legal or technical bar for the
wastes to be managed in either fashion during any given year. The fact
that refineries relied upon land treatment less in 1992 is not
necessarily indicative of future practices.
In response to the commenter's concern regarding the
transferability of wastes between land treatment and landfilling, EPA
notes that a refinery may choose different disposal practices based on
a variety of considerations, two of which are particularly important.
First, the refinery must consider the waste's characteristics. Wastes
with higher liquid content are more likely to be land treated due to
the moisture requirements of the land treatment process, while
dewatered wastes are more likely to be landfilled due to cost and waste
volume constraints (e.g., more waste costs more), and liquid content.
This is supported by the data collected in the 3007 Questionnaire,
which show that wastes sent to land treatment contain on average higher
TOG and water than wastes sent to landfills. The average oil and water
content reported for landfilled wastes were 5.9 percent and 7.5 percent
respectively, compared to average oil and water levels of 14 percent
and 17 percent for land treated wastes. The second important
consideration regarding the transferability of wastes between landfills
and LTUs is availability of the two disposal methods for each refinery.
Certainly, on-site Subtitle D LTUs are rather limited and may not be
available to many refineries. As described in information EPA provided
in the NODA, EPA's database showed only one facility with both on-site
nonhazardous landfill and nonhazardous LTUs (see Supplemental
Background Document-Listing Support Analysis, April 1997 in the docket,
p. 15) and only six nonhazardous LTUs for all refineries (ibid., p.
30). Thus, to project that large volumes of waste would shift between
landfills and LTUs appears implausible. Finally, assuming for the sake
of argument that such shifts did occur, it is possible that any change
in waste management practice for one refinery would be offset by the
opposite change by another refinery, in effect balancing out any
changes from year to year.
3. Codisposal of Wastes
Two commenters noted that the waste volumes do not reflect either
the actual or potential for codisposal of wastes (i.e., disposal of two
or more wastes in the same unit). Such codisposal of the wastes is
found in several instances in EPA's database for on-site and off-site
units receiving these wastes. The commenters argued that codisposal
would increase risks for the individual wastes evaluated by EPA,
because the greater volumes would release more toxic constituents. The
commenters noted that EPA found waste volume to be an important
parameter, especially in the groundwater model.
In response to these comments EPA first notes that its modeling for
the proposed rule and NODA did, in fact, combine volumes in cases where
the same landfill accepted multiple portions of the same waste stream
for disposal. Thus, volumes of the same residual sent to the same
landfill were aggregated and placed into the waste volume distribution
for use in modeling. In response to this comment, however, EPA expanded
its analysis in the NODA to include codisposal of all 14 residuals
examined for this listing determination that were landfilled, as well
as another set of 15 refinery wastes that were under study. This
analysis excluded only (1) wastes that were proposed for listing,
because they could no longer be placed in a nonhazardous landfill
(spent hydrotreating and hydrorefining catalysts), and (2) any wastes
that were not landfilled at all (e.g., spent caustic). EPA combined the
waste constituent and TCLP data for individual wastes by weighing the
concentrations determined for each waste according to the volume of the
wastes used. Thus, volume weighted waste and TCLP concentrations were
used to construct a hypothetical scenario of all these wastes being in
one generic on-site or off-site landfill. The codisposal analysis
showed risks below 1E-5, which EPA does not view as significant.
Revising this assessment to reflect the changes in the off-site
landfill scenario as described elsewhere in this Section, the high-end
risks were 8E-6, and remain below 1E-5 (see Table IV-2).
However, comments on the NODA argued this analysis was flawed,
because EPA used only median volumes for each waste, and did not
undertake a full sensitivity analysis for the high-end risk analysis.
In response, EPA notes that the NODA also presented a Monte Carlo
analysis of the codisposal scenario, which used the full volume
distribution for these wastes, not just the median volumes, and even at
the 99th percentile, the Monte Carlo risk was below 1E-5. After
revising the input parameters and Monte Carlo assumptions for off-site
landfills as described earlier in this Section, the Monte Carlo risks
remain low (3E-6 at the 95th percentile; see Table IV-2).
Commenters also argued that EPA's codisposal approach did not
consider codisposal with other refinery wastes in landfills that are
not under examination by EPA in the listing determination or the study.
One commenter submitted analysis that attempted to account for the on-
site codisposal of the wastes under study by increasing the combined
waste volume to include on-site landfill volumes reported in the 3007
Questionnaire. The commenter also assumed that each waste was sent to
the same landfill for 40 years. These assumptions resulted in an
increase of about 5-fold in the total volumes modeled. However, the
commenter noted merely increasing this volume alone did not
significantly increase risks for the codisposal scenario. The commenter
went on to assume that the codisposed wastes (i.e., the wastes that
were not part of EPA's current listing determination or study) would
contain sufficient benzene to leach at one-half the TC (i.e., 0.25 mg/
L). The commenter's analysis also made other changes to EPA's modeling
assumptions, including assuming all wastes leach benzene with an
efficiency of 53 percent, and that the receptor well is located on the
centerline of the plume of contamination (see discussion later in this
Section on groundwater issues). With these further set of assumptions,
the commenter estimated high-end risks up to 4E-5.
EPA does not find the commenter's codisposal analysis compelling
for several reasons. First, the assumption that the codisposed wastes
will all leach at one-half the TC level is speculative and without
foundation. In fact, the existing data available to EPA for the
refinery wastes under study show that very few of these wastes contain
such high levels of benzene. EPA has no valid reason to project that
benzene levels in other codisposed wastes would be drastically
different, as assumed by the commenter. Also, EPA does not agree with
other modeling assumptions used by the commenter, and the Agency has
arrived at a different conclusion in its modified risk analysis. As
noted later in this Section, EPA believes the commenter's assumption
about well location and landfill active life are incorrect. (EPA used a
30-year life and
[[Page 42136]]
treated well location as one of the variable parameters). EPA's revised
high-end and Monte Carlo analyses did not change significantly (see
Table IV-2), even when using the larger volume inputs. This is
consistent with the commenter's initial results, as noted above.
Furthermore, EPA notes that the final listing decisions would tend to
lower any codisposal risk, because of EPA's final listing of two other
wastes as hazardous, crude oil, and CSO tank sediment. Both contributed
leachable benzene to the codisposal analysis performed by EPA (and the
commenter), thus with these wastes removed from any possible codisposal
with the remaining wastes, any risks from codisposal should be lower
than estimated with them included.
Finally, EPA questions how relevant such a codisposal analysis
would be, even if it could be done to the commenter's satisfaction. EPA
is not attempting to list landfills that may contain a variety of
wastes, but rather the Agency is trying to determine whether an
individual waste merits listing, based on the incremental risk posed by
a specific waste. To properly factor in all wastes that are in each
landfill would require extensive site-specific information that would
be essentially impossible to gather, and would require speculation
about what wastes would be sent to a disposal unit and how long
disposal of such wastes would occur. This could create an analysis
difficult to interpret for use in listing determinations. In any case,
this is not necessary to protect human health and the environment,
because EPA's analysis shows the risks from codisposal are below levels
of concern.
EPA also evaluated the impact of codisposal on the risks from land
treatment of the wastes under study, and provided this analysis in the
NODA. Constructing a hypothetical LTU that contains all of the wastes
so managed is unnecessary, given the very limited number of
nonhazardous units that are available for land treatment. Of the 172
refineries in the 3007 Questionnaire, only 13 nonhazardous units were
reported to receive any of the residuals of concern ( 6 on-site and up
to 7 off-site LTUs). The risks from land treatment of individual wastes
were dependent on the PAH content in the waste, thus the waste with
high PAH content, CSO sediment, yielded significant risks when
evaluated by itself. As shown in the land treatment risk analysis in
the NODA, none of the other wastes when evaluated individually had
risks approaching 1E-6. EPA found only one on-site LTU and three off-
site LTUs that received more than one waste under study in 1992
containing any PAHs of concern. Because of the limited codisposal found
in LTUs, EPA examined the potential risks from the actual disposal
reported, assuming that wastes proposed for listing (most notably CSO
tank sediment) were removed. Because few other wastes had appreciable
PAH content, the codisposal analysis yielded negligible risk. Crude oil
storage tank sediment was included in the codisposal analysis, however,
EPA has since decided to list this waste. Therefore, removing this
waste, which contains moderate levels of PAHs, from any codisposal
analysis would further reduce the likelihood that codisposal of the
unlisted wastes in LTUs will yield significant risk.
4. Impact of Hazardous Characteristic Regulations
Wastes Exceeding the TC
Some commenters stated that the risk assessment in the proposed
rule overstates the risks from benzene and arsenic (the key
constituents of concern for the wastes proposed for listing) because
EPA included benzene and arsenic TCLP concentrations in excess of the
TC limit for these compounds. The commenters suggested that EPA should
calculate groundwater risks from Subtitle D landfill disposal of crude
oil tank sediments and spent hydrotreating/hydrorefining catalysts by
using only the data that does not exceed the TC limit. Commenters noted
that EPA's risk assessment assumed that no RCRA Subtitle C controls
were in place for any of the management scenarios; therefore, including
any waste samples that exhibited the TC (i.e., for benzene) in the risk
assessment would lead to unrealistically high risk.
To respond to the commenter's concerns, the Agency presented
further analysis in the NODA resulting from groundwater modeling runs
in which the input TCLP data for wastes that exceeded the TC threshold
were ``capped'' at the TC level. Thus, EPA used the assumption that
wastes could contain toxic constituents at or near the TC threshold,
and that such data should be included in the risk assessment. EPA notes
that the groundwater risk analysis in the proposed rule, as well as in
subsequent analyses, did not include waste volumes reported in the 3007
Questionnaire to be hazardous and sent to hazardous waste Subtitle C
landfills in the volume distributions used in modeling risks from
nonhazardous Subtitle D landfills. EPA believes this is reasonable
because these volumes were handled as hazardous and would not affect
risks from Subtitle D units. This point is discussed further in the
following section in the context of comments on volumes used in
modeling LTUs.
The final revised groundwater analyses (see Table IV-2) showed some
reduction in risks, using the TC-capping assumptions. However in all
cases the high-end risks for these TC-capped runs exceeded the 1E-5
risk level for both benzene and arsenic. The 95th percentile Monte
Carlo risks also exceeded 1E-5 for one key constituent (arsenic) for
the spent hydrotreating and hydrorefining catalysts analysis. The TC-
capping has essentially no effect on groundwater risks from arsenic in
these catalysts, and the modeling results for these specific wastes are
discussed in more detail below and in Section V.C.3.
Two commenters responded to the Agency's analysis on the capping of
waste concentrations at the TC levels by arguing that EPA's ``cap'' was
too high, and provided alternative methods that would result in lower
input values for benzene and arsenic for the spent hydrotreating and
hydrorefining catalyst wastes. EPA had capped the average TCLP input
data for the high-end analysis at the TC level, while the commenters
suggested capping each individual sample before averaging. The
commenters noted that EPA's Monte Carlo analysis used the original TCLP
data and substituted the TC threshold for individual values that
exceeded the TC. Using the approach applied by EPA in the Monte Carlo
analysis, the commenters calculated that the average TCLP
concentrations decreased to 60 percent of the TC level used in the
high-end analysis.
The Agency believes that its approach is more appropriate for the
conservative high-end risk analysis, but notes that the Monte Carlo
analysis, effectively, does what the commenter suggests. The Agency
performed the TC-capped analysis to assess the level of risk that might
occur, assuming wastes that exceed the TC threshold are managed as
hazardous wastes. Therefore, EPA believes that capping the actual input
to the high-end model is appropriately conservative. As discussed in
detail in the discussions for specific residuals (see Section V.C), the
Agency believes that even the Monte Carlo TC-capping analyses support
listing these wastes.
For the catalysts, EPA notes that using this alternative approach
in the high-end analysis is unlikely to affect the listing decision
because: (1) the pyrophoricity of the wastes supports listing these
wastes, (2) the arsenic risks would remain very high under either TC-
capping approach, and (3) the high-
[[Page 42137]]
end risks for benzene remain of concern. To explain the second point,
EPA notes that the TC-capping has no effect on hydrotreating catalyst
because none of the samples exceed the TC level for arsenic. For
hydrorefining catalysts, which did have some values above the TC level,
even if the lower average arsenic input levels assumed by the
commenters were used, the arsenic risks would remain above 1E-4. (Note
that the risk results are not very sensitive to the TCLP input level
for arsenic under the conditions modeled, because this chemical moves
very slowly in groundwater, causing the maximum receptor well
concentration to be relatively insensitive to the starting leaching
concentration.)
Another commenter objected to capping waste samples at the TC
level, particularly for benzene, arguing that this implies the toxicity
characteristic may be an appropriate alternative to listing the wastes.
The commenter stated the TC-capped modeling and the underlying
implications are wrong because (1) the TCLP is unreliable for oily
wastes, (2) a generator may apply ``knowledge'' in lieu of testing, (3)
generators may render inaccurate determinations, and (4) the
characteristic does not consider the high PAH content of some wastes.
EPA generally agrees that for the wastes at issue, crude oil tank
sediment and spent hydrotreating/hydrorefining catalysts, the TC does
not provide sufficient regulatory control for the various reasons
stated in the residual specific discussions in Sections V.C. As shown
by the TC-capped modeling analysis, the risk levels remain at levels of
concern, whether or not EPA assumes wastes exceeding the TC levels
would be managed as hazardous. Furthermore, as discussed later in this
section on the use of the TC as an alternative to listing, EPA believes
that listing these wastes is supported by other factors.
EPA does not agree with the commenter's claim that the TCLP is
unreliable for the wastes evaluated in today's rule (see discussion at
the beginning of Section V.B.1). While EPA agrees that inaccurate
determinations by generators may occur due to the difficulties
associated with sampling some wastes (see discussion in Section V.C.1),
the Agency believes that the use of a generator's knowledge in lieu of
testing is appropriate in many cases. Finally, the Agency agrees that,
to the extent potential risks from PAHs are not controlled by the TC,
wastes should be listed. This may occur because PAHs are not TC
constituents, as noted in the following section on use of the TC as an
alternative to listing. Therefore, if a particular waste exceeds TC
levels only some of the time, any PAH risks would not be adequately
covered for those instances where the waste does not exceed the TC
levels.
Eliminating Hazardous Waste Volumes
In allocating volume inputs for the groundwater and nongroundwater
modeling, EPA omitted waste volumes that were reported to be hazardous
(i.e., exhibited a characteristic defined in 40 CFR 261.24). EPA had
not done this in the proposal for wastes sent to land treatment, and
for inadvertently modeled hazardous waste volumes that were, in fact,
disposed of in permitted hazardous waste LTUs. EPA corrected this in
the risk analysis for land treatment presented in the NODA. One
commenter disagreed with EPA's approach of not counting waste volumes
managed as hazardous in 1992, and noted this dramatically reduced the
high-end volumes of crude oil storage tank sediment used as input to
the NODA risk assessment for land treatment disposal. The commenter
stated that the ``recalculations'' for land treatment volumes are based
on the unverified assumption that because certain wastes were managed
in 1992 as hazardous, they will always be managed as hazardous. The
commenter argued that by excluding these wastes, EPA is implicitly
relying on the existing TC in lieu of listing the waste, and therefore
making the same policy errors as the landfill TC-capping modeling
(discussed above).
EPA does not agree with this comment. The wastes that were excluded
for the revised land treatment modeling were, in fact, reported to be
hazardous in the 3007 Questionnaire. While some wastes may exhibit a
characteristic sometimes, and not at others, EPA has no reason to
believe that 1992 was not a typical year. Thus, EPA could reasonably
assume that similar amounts would be hazardous from year to year, and
such variation should not lead to significant changes in the risk
analysis. While excluding these volumes does rely on the TC as the
commenter noted, this reliance seems justified because these wastes
did, in fact, exhibit the TC and were reported to be managed as
hazardous. Furthermore, EPA notes that the waste of primary concern to
the commenter, crude oil tank sediment, is being listed as hazardous in
any case due to groundwater risks from landfill disposal. For the other
wastes modeled in LTUs, removal of volumes regulated as hazardous did
not alter the risk results significantly, i.e., the median and 90th
percentile volumes were only slightly different (see Table 2.1 in the
NODA nongroundwater risk assessment background document, Supplemental
Background Document; Nongroundwater Pathway Risk Assessment, March,
1997).
Use of the TC as an Alternative to Listing
Some commenters indicated that the use of the TC adequately
regulates potential risks, and therefore, makes listing of the refining
process residuals unnecessary. Others commented that the TC does not
adequately capture wastes that should be regulated, and supported the
proposed listings.
In response, the Agency notes that its listing decisions are based
on a weight-of-evidence approach, which evaluates various factors,
including the results of the risk analysis. In general, EPA may
consider listing wastes that frequently exhibit a characteristic if
risks are not adequately controlled by the characteristic. The TC, for
example, was based on an evaluation of potential threats constituents
may present if released to groundwater (see 55 FR 46369; November 2,
1990). Thus, for a waste that is TC hazardous, EPA may consider listing
if other pathways besides groundwater present a risk, if other
constituents in the waste are not included in the list of TC
constituents, or if a waste with levels of TC constituents below
characteristic thresholds still shows significant risk for some
situations.
In today's rule, EPA is finalizing listings for the two spent
catalysts and crude oil tank sediment, even though these wastes are
often characteristically hazardous, because risks from landfilling
these wastes are not adequately controlled by the TC (see specific
waste discussions). Furthermore, EPA is listing another waste, CSO tank
sediment, that often exhibits the TC characteristic for benzene,
because the TC does not effectively control risks presented by PAHs in
LTUs via nongroundwater pathways. The TC was developed to provide
protection against potential risks from the contamination of
groundwater by leachate from land disposal units, and was not designed
for nongroundwater pathways. In addition, PAHs are not on the list of
TC constituents.
5. Other General Risk Issues
Consistency With Past Listings
One commenter stated that EPA's methodology for the current listing
determination is inconsistent with previous Agency practice and policy,
[[Page 42138]]
specifically with the finalized carbamates listing and the previous
petroleum listing. The commenter noted that, for the carbamates listing
rule (February 9, 1995; 60 FR 7825), EPA computed landfill waste
volumes according to the quantity of wastes that could be landfilled,
not just the quantity that happened to be landfilled in the reporting
year. The commenter provided examples in the current listing proposal
where waste volumes for land treatment exceeded the volumes for
landfilling, and argued that the volumes used in the landfilling
assessment were therefore too small. The commenter also noted that EPA
considered the codisposal of solvents and other oily wastes in
petroleum refining waste management units as part of its 1990 listing
determination for refinery wastewater treatment sludges, F037/F038
(November 2, 1990; 55 FR 46354).
As a general response, EPA notes that the commenter did not take
into consideration the evolving nature of the Agency's risk assessment
process and policies. EPA's risk methodologies have progressed over the
years, and the modeling tools have been refined. The earlier rule cited
by the commenter, the listing decision for treatment sludges (F037/38),
did not, in fact, rely on modeling, but rather used a more simplistic
approach based on a comparison of waste constituent concentrations to
health-based levels. Given the modeling tools currently available, EPA
no longer believes such an approach is appropriate, because it does not
take into account the potential for waste constituents to be released
from the waste units, their fate and transport in environmental media,
and the levels to which receptors may ultimately be exposed. In today's
rule, EPA has used various models to estimate the release and transport
of the toxic chemicals of concern, and the Agency believes such an
approach is more useful in projecting the potential risk to exposed
individuals.
While EPA did perform modeling as part of its risk assessment in
the carbamates listing cited by the commenter, this was essentially the
first time the Agency attempted to use such modeling to support listing
decisions. Thus, EPA made various simplifying assumptions. For example,
EPA created a hypothetical off-site landfill for modeling by assuming
that all of the carbamate wastes under examination would be placed in
the same off-site unit. Such a simplifying assumption would be
unrealistic in the current rulemaking, given that the petroleum
refining industry consisted of 185 facilities in 1992, and that these
facilities were widely distributed throughout the country (for
comparison, the carbamates industry comprised 23 facilities). To use
the same approach as was used in the carbamates rule, i.e., to assume
disposal of all wastes in one landfill, does not appear reasonable in
the current rulemaking.
Therefore, EPA believes that the approach used in today's rule is a
reasonable progression of EPA policy. For responses to the specific
comments related to the use of volumes reported for land treatment and
landfills, see the discussion on Waste Management Assumptions, which
appears earlier in this section. Elsewhere in this rule EPA also
responds to comments related to codisposal (Section V.B.3) and co-
solvency (Section V.B.1).
The commenters also argued that previous listing determinations
were based on lower levels of contaminant concentrations than those
found in wastes being considered in this notice, and that the wastes
under consideration in this rulemaking should be listed. For example,
the commenter pointed out that the average total concentration of
benzene and PAHs, such as benzo(a)pyrene found in crude oil tank
sediment exceeds the level of benzene in F037 and F038 that caused
those wastes to be listed in 1990.
EPA recognizes that crude oil tank sediment and other residuals
characterized in this listing determination may contain concentrations
of some constituents comparable to previously listed wastes, including
the F037 and F038 refinery residuals. However, direct comparison of
these concentrations to previous listing benchmarks is not an adequate
basis for listing. Listing determinations consider many factors beyond
the concentrations of constituents in a waste, including the waste
volume, constituent mobility, management practices, damage cases, other
regulatory controls, etc. (see 40 CFR 261.11(a)(3)). As noted above,
the listing of F037/F038 sludges did not use modeling for support, but
instead relied on constituent concentrations, as well as various other
factors. The other factors that EPA relied on in this listing included
the very large volumes of F037/F038 generated (over 400,000 metric tons
per year), the widespread use of surface impoundments to manage the
wastes, and damage cases. Therefore, merely comparing constituent
levels may not provide a useful measure of what wastes should be
listed. Furthermore, as noted above, EPA's risk assessment process has
evolved, and the Agency has developed a more sophisticated set of risk
assessment tools than were available for listing determinations in
1990. As a result, EPA believes that it is better able to measure and
predict risk now than previously, and that the better procedures and
methodologies should be used.
Individual Versus Population Risk
Several commenters stated that the population risks estimated by
EPA do not justify a decision to regulate the wastes proposed for
listing (hydrotreating and hydrorefining and clarified slurry oil
sediment), and that consideration of the risks posed by these landfills
to the entire population potentially exposed would lead to the
conclusion that these residuals do not pose substantial hazards to
human health, and thus, should not be listed as hazardous wastes.
Commenters argued that EPA's failure to give serious consideration to
the low levels of population risk is at odds with the statute, the
listing criteria, and regulatory precedent within the federal
government. The commenters claimed that, due to the low populations
risks, EPA cannot conclude that any of these residuals ``is capable of
posing a substantial present or potential hazard to human health or the
environment,'' as required in 40 CFR 261.11, and should not list any of
these residuals.
In response, EPA notes that ``population risk'' is not explicitly
used in either the RCRA statute or the hazardous waste listing
regulations in 40 CFR 261.11. EPA does not believe it is appropriate to
allow contamination from waste management units to cause substantial
risk to nearby residents simply because there are few wells in the
immediate area. In addition, the regulation cited by the commenter
clearly states that wastes are to be listed if they are ``capable of
posing a substantial present or potential hazard'' (emphasis added).
Thus, the Agency must protect against potential, as well as present
risks that may arise. The Agency's decision to list these wastes is
based primarily on the concern over risks to those individuals who are
significantly exposed, even if there are relatively few of them.
Population risk is only one of many factors to be considered in
Agency decisions, and there are numerous precedents where the Agency
has taken action, for example at Superfund sites and in previous
listing determinations, when there are relatively few people
potentially affected. See, for example, the report entitled Land and
Soil Health Risks from CERCLA (Federal Superfund), and WQARF (State
Superfund) Sites, Arizona Department
[[Page 42139]]
of Environmental Quality, 1995, in the docket for today's rule, which
concluded that population risks were low because the number of people
exposed to groundwater contamination is small. The Agency has stated
that the key objective of the CERCLA National Contingency Plan (NCP) is
to protect individuals at contaminated sites (see 55 FR at 8710), and
rejected using population risk as the point of departure for setting
clean-up levels (see 55 FR at 8718). In addition, the CERCLA
regulations (see 40 CFR 300.430(e)(2)(i)(A)(2), and 55 FR at 8848)
direct EPA to establish preliminary remediation goals for carcinogens
based on ``cancer risks to an individual.''
Population risks arising from contaminated groundwater due to waste
management are expected to be low, because often only a limited number
of domestic wells will be near these facilities, and groundwater moves
very slowly. EPA's Guidance for Risk Characterization (USEPA Science
Policy Council, February, 1995) states that, when small populations are
exposed, population risk estimates may be very small, however, ``in
such situations, individual risk estimates will usually be a more
meaningful parameter for decision-makers.'' Finally, it is important to
note that the Agency is also concerned about the loss of the
groundwater resource for the future, which could be of particular
concern if land use patterns were to change and there were a future
demand for the resource. In this case, beneficial uses would be
precluded or, if the potential users were unaware of the contamination,
risks could occur.
Additive Risks From Multiple Units
One commenter stated that risks posed through different groundwater
and nongroundwater pathways should be summed when the potential for
simultaneous exposure exists, but that EPA instead assumed that
groundwater exposures were occurring after the nongroundwater
exposures. The commenter noted that the time of travel for benzene and
perhaps other mobile constituents in EPA's groundwater risk assessment
is 17 years or less, clearly within the period of time nongroundwater
exposures may occur.
EPA does not agree with the commenter's suggestion that groundwater
and nongroundwater risks should be combined. This is because, as
discussed previously, EPA's analysis showed that groundwater risks are
only potentially associated with landfills, and nongroundwater risks
are only potentially associated with LTUs. Therefore, the only
potential for the combination of groundwater and nongroundwater risks
to be significant, would be for a situation in which a landfill was
located in close proximity to a LTU. EPA examined the information
provided in the 3007 Questionnaire for any sites where landfills and
LTUs are co-located, and presented the results in the April 1997 NODA.
This analysis showed only one facility at which a nonhazardous LTU and
landfill were both located at the same site, and even in this one case
the units are approximately 5,000 feet apart, making significant
simultaneous exposure unlikely.
6. Specific Groundwater Modeling Issues
Active Life of Landfills
Two commenters disputed EPA's assumption of 20 years for the active
life of landfills to estimate the total volume of a specific waste
placed in a landfill, and argued that the report and data for off-site
landfills used by EPA to make this assumption (National Survey of Solid
Waste (Municipal) Landfill Facilities, EPA/530-SW88-034, September
1988) actually demonstrate an active life of at least 40 years. The
commenters believed that this is an important difference, because this
would increase the total waste volume used as input to the groundwater
models and result in increased risks.
In response, EPA reexamined the report cited and concluded that the
assumed active life of 20 years may be an underestimate. Using the data
in the report, however, the Agency calculated that an average active
life of 30 years is more appropriate for us in the risk assessment,
rather than the 40-year life suggested by the commenter. EPA believes
that the commenter simply summed the reported average age of the
landfills (19 years) and the average remaining life (21 years) to
obtain 40 years. However, this calculation is not appropriate, because
it would overestimate the active life for existing units. This is
because the average age in the report included closed units, not only
existing units, and thus does not reflect the average life for those
units still in operation. Likewise, the average remaining life given in
the report included planned units, as well as existing units, and this
also would tend to inappropriately increase the apparent active life
for existing units. Correcting for this by eliminating closed and
planned units, EPA calculated a 30-year active life, based on corrected
values of 16.5 years for the average age of active units, and 13.3
years for the average remaining life of active units (see Additional
Listing Support Analysis, 1998, in the docket to today's rule for full
calculations). EPA has used the revised active life (and
correspondingly larger volumes) to calculate the new risk numbers given
in Table IV-1.
The same commenters also argued that EPA's use of a 20-year life
for on-site landfills was wrong. In the NODA, EPA provided an analysis
of the data for on-site landfills for refineries from the 3007
Questionnaire, showing a calculated median of about 21 years for on-
site landfills. The commenter continued in comments on the NODA to
dispute the 20-year calculation, and cited an alternative method
presented by EPA in the NODA to calculate a 39-year average (i.e.,
mean) active life, which the commenter argued EPA should use.
In the NODA analysis, the Agency used the projected date for
closure of on-site landfills reported by refineries in the 3007
Questionnaire to estimate active lives. EPA also examined an
alternative method to calculate on-site landfill life for use when
facilities did not report the projected date of closure. Under this
alternative method, EPA used the remaining capacity reported for the
units, assumed disposal rates for all wastes in the landfills would
remain constant, and thereby estimated when the landfill may reach full
capacity. EPA believes the direct method chosen is most appropriate
because it uses the actual landfill lives reported in the 3007
Questionnaire, rather than relying on estimating remaining active life
by projecting past waste disposal rates into the future. The
alternative approach is especially uncertain when the landfill is
relatively new, thereby requiring the extrapolation of a small
percentage of used landfill capacity into the far future, which means
that small variations or errors in the used capacity of a landfill may
lead to widely varying landfill life projections. Thus, EPA did not
revise its modeling for on-site landfills to reflect a longer landfill
life. EPA also used the median active life, rather than the mean
suggested by the commenter, because the median value lessens the impact
of widely variable data and outliers. For example, a few very large
values in a data set would have a major impact on the mean, but the
median would not be overweighted by the few very large values. EPA
notes that the only data available for off-site municipal landfills
were average values, not medians, so the Agency had no choice but to
use the average estimate active life for the off-site landfills.
Furthermore, EPA notes that many of the wastes of concern, such as
the
[[Page 42140]]
sediments from storage tanks, are generated only intermittently, since
facilities clean out crude oil storage tanks about every 5-10 years.
While refineries may have many such tanks of different ages, EPA
estimates that a typical refinery may generate such a clean out waste
about every 1.5 3 years. In effect, a typical facility may not dispose
of the tank sediments in on-site units every year, but approximately
every 2 years. Therefore, even assuming arguendo that the on-site
active life might be about 40 years, as the commenter suggested, if
tank sediment is only generated every two years or so, the total volume
of a specific waste in the unit may more closely resemble 20 years
worth. EPA notes that, unlike on-site units, off-site landfills may
accept waste from other refineries, thus disposal may well occur every
year. Therefore, the 30-year active life used for off-site units is a
more appropriate measure of the number of years a specific waste may be
disposed.
Finally, EPA notes that because the revised risks from off-site
landfills were somewhat greater than risks from on-site landfills for
the wastes of most concern to the commenter that the Agency is not
listing (i.e., unleaded gasoline tank sediment, and HF alkylation
sludge), the off-site risks are likely to be determinative in any case.
Waste Unit Area
Two commenters believed EPA should have used larger waste unit area
sizes in its groundwater risk assessment, and that this would result in
the listing of more refinery wastes. These commenters questioned EPA's
decision to vary on-site landfill sizes for different petroleum wastes
when projecting mismanagement scenarios. The commenters argued that
since any petroleum waste can be disposed in any on-site landfill, EPA
should assume that any waste will be disposed in units representing the
largest landfills. The commenters believe that a larger waste unit area
would result in a higher concentration at the receptor well, and that
EPA underestimated the risk associated with several of the wastes the
Agency decided not to list.
In response, EPA notes it used waste quantity and on-site landfill
sizes in the modeling analysis for individual waste streams from the
RCRA 3007 Questionnaire responses, which are based on actual petroleum
waste management practices. EPA disagrees that a refinery would
necessarily use a landfill to dispose of any number of wastes, and the
Agency believes that there are indeed reasons why a facility would not
dispose all its generated waste in an on-site landfill, including
permit limitations and liability considerations. EPA verified such
limited or segregated management practices during site visits. For
example, EPA reviewed site visit reports for four facilities that
operated on-site nonhazardous landfills. Two facilities manage
Fluidized Catalytic Cracking (FCC) catalyst and fines, but no other
listing or study wastes in their landfills. The other two operate the
on-site landfills for disposal of only some of their generated wastes.
Other wastes are disposed off-site or recycled. EPA believes its
approach of calculating different unit areas for different wastes was
reasonable because they are reflective of actual operating practices,
and another approach may result in unrealistic or unreasonable
assumptions regarding waste management practices. As noted in the above
section on waste management assumptions, a refinery may choose
different disposal practices based on a variety of considerations,
including the waste's characteristics and access to landfill capacity.
Furthermore, it is not necessarily true that the larger the landfill,
the higher the resulting receptor well concentration. The modeled
receptor well concentration is a function of a number of parameters,
such as waste volume, leachate concentration, the concentration of
constituent in the waste, and various chemical transport properties.
Thus, for a given waste volume, a larger landfill area will not
necessarily produce higher well concentrations.
The commenters also stated that the standard off-site landfill
areas used by EPA were arbitrarily small (2,020 square meters
(m2) median; 162,000 m2 high-end). The commenters
noted that EPA apparently derived these area sizes from an industrial
landfill survey taken of on-site industrial waste landfills, and
therefore the areas are inappropriate to use for off-site units. The
commenters went on to state that the Agency should use data available
for municipal solid waste landfills for the off-site modeling, (i.e.,
the same database EPA relied on for length of active life.) They noted
that the areas reported for active municipal waste landfills in EPA's
1988 survey appear many times greater than the volumes used by EPA.
EPA agrees first that the median area used by EPA in this analysis
was in error, and believes that the data for off-site municipal
landfill area cited by the commenter are more appropriate for modeling
off-site landfills than the industrial database used by the Agency.
This is primarily because, as the commenter noted, the database
originally used by EPA reflected landfill areas collected from what are
likely industrial on-site landfills, rather than off-site landfills.
EPA does not have, at this time, any area data for off-site industrial
nonhazardous landfills, so the Agency has decided to use the data
available for off-site municipal landfills. The use of municipal
landfill data is entirely appropriate because the refineries reported
in the 3007 Questionnaire that close to one-half of the wastes disposed
off-site went to municipal landfills. Therefore, EPA revised the
groundwater modeling for off-site landfills to reflect the larger areas
associated with municipal landfills, and the risk results in Table IV-2
incorporate the revised landfill areas.
Noningestion Exposures for Groundwater
One commenter stated that EPA's groundwater risk assessment only
considered the impact of ingestion of the water, but ignored potential
risks from inhalation and dermal absorption of contaminants that might
arise from the use of water in the home (e.g., showers or bathing).
Such an additive affect would increase the overall risks from
groundwater exposures.
EPA agrees with the commenter that the noningestion exposure route
for groundwater may be important for some constituents. The Agency
presented its analysis of such noningestion risks in the NODA. For the
wastes under study, this was only significant for benzene (no other
toxic constituent of concern was volatile enough to affect the risk
evaluation). EPA's analysis resulted in effectively increasing risks
from benzene projected to reach a receptor well by about 60 percent
over the ingestion risk (See Chapter 5, Supplemental Background
Document for Groundwater, 1997.)
Biodegradation of Benzene
Five commenters argued that the biodegradation of benzene should be
considered in estimating the potential risks from Subtitle D
landfilling of spent hydrotreating catalyst, spent hydrorefining
catalyst, and crude oil storage tank bottom sediment. Two commenters
used the groundwater model used by EPA (EPACMTP) to show that
concentrations of benzene in groundwater decrease when a conservative
biodegradation rate is assumed. Several commenters calculated benzene
biodegradation rates to show that both anaerobic and aerobic
biodegradation processes limit the subsurface transport of benzene in
particular, and related aromatic hydrocarbons in general (benzene,
[[Page 42141]]
toluene, ethylbenzene, and xylenes, also known as BTEX). Commenters
believed that the studies are relevant because the levels of BTEX
compounds in the wastes' leachate are comparable to levels measured in
the studies. Commenters argued, although the studies do not follow the
Toxic Substances Control Act (TSCA) protocol developed by EPA to
document biodegradation, the results should be viewed as comparable by
EPA because they are presented in peer-reviewed journals.
EPA conducted an evaluation of all submitted data and the
documented anaerobic biodegradation studies of benzene suggest that in-
situ anaerobic biodegradation of benzene rates are strongly dependent
on site-specific conditions (e.g., availability of chemicals to act as
electron acceptors, availability of nutrients, temperature). The
necessary conditions for anaerobic benzene biodegradation are poorly
understood, and the absence of biodegradation can be caused by the
presence of competing substrates, such as toluene, xylenes and
ethylbenzene, as well as inadequate geochemical conditions and lack of
proper electron acceptors (e.g., nitrate, sulfate, iron). Therefore,
because of the lack of information to correlate site-specific
controlling factors to biodegradation, the limited number of field
data, and the field and laboratory evidence that benzene tends to be
recalcitrant to anaerobic biodegradation, biodegradation of benzene was
not considered directly in the groundwater analysis. However, EPA did
complete preliminary modeling for the proposed rule that incorporated
assumed rates into the analysis to see what impact this might have on
receptor well concentrations (see the Petroleum Refining Listing
Determination Background Document for Ground Water Pathway Analysis,
1995, in the docket for details). When assuming degradations rate of
0.00001 and 0.0001 per day, the well concentrations for all wastes
examined decreased by approximately 2 percent and 44 percent,
respectively. In addition, there may be a degradation ``lag time,''
which is the time period between the introduction of a constituent into
the subsurface and the start of actual biodegradation. This time
reflects the period subsurface microbial populations may need to
acclimatize to the organic substrate before degradation may occur.
Thus, if the lag time were 10 years, the decrease in the well
concentration due to biodegradation assuming the higher decay rate of
0.0001 day, would be lowered to only 22 percent. These results suggest
that using a conservative degradation rate would not significantly
alter the risk results for benzene. For example, even assuming
biodegradation of benzene lowered the high-end risks for this
constituent by about 50 percent, the risks would remain above 1E-5 for
the hydrotreating/hydrorefining catalysts and crude oil storage tank
sediment.
EPA plans to study further the modeling of anaerobic biodegradation
in the saturated zone of hazardous constituents from hazardous wastes
and the physical conditions under which anaerobic degradation occurs
where the Agency has developed sufficient data to permit such an
analysis.
Location of Receptor Well
The distance from the landfill to the receptor well is an important
parameter in the groundwater model, because the projected
concentrations of constituents at the well, and the corresponding
risks, increase as the well location is moved closer. EPA received
comments from six commenters on the value used by the Agency for the
distance to the nearest well from a landfill. One of the commenters
felt that EPA should have used a smaller distance, while the remaining
commenters felt EPA's value was too small.
One commenter believed EPA should have used the distance to the
nearest well for off-site landfills that the Agency used in past
listings, (i.e., 48 meters used in the dye and pigment proposed listing
determination.) This value was less than half the value used for the
petroleum listing determination. The commenter suggested that EPA
perform the two parameter high-end analyses using the 48-meter distance
to the receptor well.
In response, EPA notes that in its Monte Carlo analysis the Agency
used the full distribution of available receptor well distances,
including wells at smaller distances. The risk results for wastes of
concern were presented in the NODA, and were subsequently revised as
described elsewhere to yield the final results in Table IV-2 (see
Section IV.B, and the groundwater background document in the docket,
Additional Groundwater Pathway Risk Analyses, 1998). Concerning the
well distance used in the dyes and pigments rule, EPA notes that the
Agency used essentially the same underlying well distance data in this
rule as was used in the dyes and pigments proposed rule. The apparent
high-end value used in this earlier rule (46 meters, not 48 meters
cited by the commenter) represents the 95th percentile distance, and
104 meters is the 90th percentile. However, EPA states in the dyes and
pigments rule risk documentation (see page 21, Health Risk Assessment
Background Document for the Dyes and Pigments Manufacturing Industry,
November, 1994, in the docket for that rule) that the high-end well
distance of 46 meters was chosen because this was the 90th percentile
value. But as Table IV-2.7 in the dyes and pigments risk document
shows, the 90th percentile value actually was 104 meters, nearly the
same as the 102 meters high-end value used in the current petroleum
rulemaking. Therefore, the use of 46 meters in the dyes and pigments
rule as the 90th percentile distance was an oversight. Regardless, EPA
believes that the 90th percentile value is more appropriate to use in
the type of high-end sensitivity analysis performed for this
rulemaking, and that the 95th percent value would be unreasonably
conservative. EPA believes that setting two critical parameters to the
90th percentile level is a reasonable approach to generate high-end
risks that are above the 90th percentile, but still realistically on
the distribution. Such an approach is consistent with EPA guidance (see
Habicht, 1992). EPA's Monte Carlo analysis for the groundwater pathway
supports this approach, i.e., the revised groundwater risks presented
in Table IV-2 show that the high-end risks are above the 95th
percentile risks estimated from the Monte Carlo analysis. Therefore,
EPA believes its approach is appropriately conservative.
The commenter also argued that the distance to the nearest well
used in the groundwater assessment was inconsistent with the distance
to the nearest receptor EPA used in the nongroundwater risk assessment.
The commenter noted that the high-end value of 102 meters used for
groundwater well distance is inconsistent with the high-end value of 75
meters EPA used for the nearest residence in the nongroundwater risk
assessment, and that this discrepancy between the distance values is
never addressed or justified.
EPA disagrees that the distances must be equivalent, because
different pathways are represented in each assessment. Exposure from
groundwater pathways occurs through potentially contaminated drinking
water wells. Exposure from nongroundwater pathways occurs through
multiple exposure routes, such as run-off and air releases from LTUs,
and the point of exposure is considered the location of the residences
nearest the LTU. Therefore, EPA used different data sets to estimate
receptor distances for these pathways to account for well locations
[[Page 42142]]
for groundwater and residences for the nongroundwater pathways. For
distances to residences in the nongroundwater pathways, EPA used
information compiled for Treatment Storage and Disposal Facilities
(National Survey of Hazardous Waste Generators and Treatment, Storage,
Disposal, and Recycling Facilities in 1986: Hazardous Waste Management
in RCRA TSDR Units, July 1991). These values were used instead of the
ones used for groundwater because they reflect the distances to
receptors being modeled, (i.e., residences at which people may be
exposed to air releases or contaminated soils.) The distances to
residences will not necessarily correspond to drinking water well
distances.
Four commenters felt that EPA should have used data from the 3007
Questionnaire to calculate the distance to the nearest receptor well,
which would result in a larger distance. Three of these commenters felt
that EPA's decision to use values from the OSW Subtitle D Waste
Management Facility Database was inconsistent with its earlier
determination to base other information for its rulemaking on the 3007
Questionnaire. They believed that the RCRA 3007 Questionnaire obtained
sufficient data from respondents, and that data from this Questionnaire
is more appropriate, since unlike the OSW data, the data are specific
to refineries and residuals considered for this listing. Two commenters
suggested that if EPA felt there was insufficient response to the 3007
Questionnaire, EPA should have contacted non-respondents for further
information.
Because of the lack of completeness of the reported well distances
in the 3007 Questionnaire, the Agency decided to use well distances
from the Subtitle D Survey Database. The 3007 Questionnaire response
was incomplete and inadequate. Of the 172 3007 Questionnaires returned,
27 facilities reported the presence of nonhazardous on-site landfills
used for the disposal of any waste in the survey in any year. Of these
27, EPA found that only 15 reported the distance to the nearest
drinking water well with any reliable documentation (e.g., well
location maps, groundwater flow gradients, company survey of nearby
wells). This limited data set is not surprising given the difficulty
associated with seeking off-site information from the refineries that
is not related to on-site operations. Furthermore, wells may be placed
closer to the on-site landfills in the future. Therefore, EPA relied on
distances obtained from the Office of Solid Waste (OSW) database as
more representative of potential well locations. EPA notes that the
3007 Questionnaire only provides well location information for
evaluating on-site landfills, and even if used, would not have impacted
the modeling results for off-site landfills. Because the risks from
off-site landfills were higher or comparable to risks calculated for
on-site landfills, any change in the results for on-site landfills is
unlikely to alter any decisions to list wastes.
Two commenters disapproved of EPA's methods for locating the
receptor well in the contaminant plume for EPA's high-end and Monte
Carlo analyses. The commenters argued that EPA should have assumed that
the well is always located on the centerline of the contamination
plume, in accordance with previous Agency listing determinations, and
not have varied well locations across the width of the plume. The
commenters submitted modeling results purporting to show that locating
the receptor well on the centerline would increase risk such that a
listing is required for most petroleum refinery wastes covered by the
NODA.
EPA defined the well location for modeling purposes by using the
distance perpendicular to the plume centerline (Y coordinate) and the
distance from the landfill to the well (X coordinate). The X distance
to the well was discussed in the preceding comments. In the high-end
analysis completed in the proposed rule, EPA fixed the Y coordinate of
the receptor well location half-way between the plume centerline and
the edge of the plume. However, the Agency has revised the two high-end
parameter evaluations using a full sensitivity analysis for each waste,
in which the Y-location of the well was either placed on the plume
centerline (the high-end value) or at plume half-width (the median
value). EPA also has performed Monte Carlo analyses in which the
receptor well location was varied in such a way that the location
reflected the nationwide distribution given in the USEPA database of
Subtitle D landfills. The final revised Monte Carlo analyses used the
available distance to well data (X coordinate) as noted earlier, and
then randomly placed the well anywhere within the projected plume. Both
of these approaches are more appropriate than what the commenter
suggested, because placing the well on the plume centerline will tend
to overestimate risks in affected wells by not considering other well
locations. Therefore, EPA does not agree with the commenter, and
believes that the approaches used by the Agency in the revised risk
analysis fully considered well placement. In any case, EPA notes that
the modeling submitted by the commenter shows that simply holding the
well location on the centerline has little impact on the results. For
example, the commenter's analyses that assumed the receptor well was
always on the centerline yielded very minimal increases of zero to
eleven percent for the four wastes they modeled in off-site landfills
(see Appendix A in ``Analyses Using EPACMTP to Estimate Groundwater
Pathway Risks from Disposal of Petroleum Refinery Wastes'' King
Groundwater Science, in comment F-97-PRA-0005.A).
Finally, in conducting the Monte Carlo analysis for the NODA, the
Agency made a key assumption concerning well location, which was
inconsistent with the assumption made for the deterministic analysis.
In the high-end analysis, the downgradient wells of concern were
assumed to be those within the plume of contamination from the
landfill, as noted above. For the Monte Carlo analysis, all potential
wells within a 180-degree arc downgradient from the landfill were
included, thus including wells that would never be affected by
contamination from the landfill. Each approach can provide valid
assessments of risk distributions, but the two approaches describe
risks for different populations of receptor wells. Upon further
consideration of this issue, the Agency determined it is most
interested in risks at well locations that could be affected by the
landfill. Including wells that, because of their location, could not be
affected no matter how toxic or mobile the waste constituents, provides
EPA with little information about the waste on which EPA is making a
decision. Thus, EPA has relied on the revised Monte Carlo analysis that
includes only those well locations that were within the plume. The
results of this change, along with the other revisions to waste volume
and landfill area estimates that were described earlier, show that
risks are higher than previously reported for different percentiles on
the Monte Carlo distribution. For example, the Monte Carlo risk for
landfills for crude oil tank sediment with the receptor well restricted
to the plume was 1E-5, an increase over the Monte Carlo result of 7E-6
when placing the well anywhere downgradient, and more comparable to the
high-end results from the sensitivity analysis, 4E-5. With this
adjustment in the Monte Carlo assumptions, the high-end and Monte Carlo
results appear more consistent, and EPA believes that such an
adjustment is logical.
The differences between the two different approaches in locating
receptor
[[Page 42143]]
wells in the Monte Carlo analysis is most obvious when comparing the
constituent concentrations at the well calculated to be the 50th
percentile values, otherwise known as the ``central tendency.'' By
restricting the well location to the plume, the 50th percentile
concentrations are over several orders of magnitude greater than those
predicted when the well location is allowed to be outside the plume.
(See Additional Groundwater Pathway Analysis, 1998, section 5.3.1, in
the docket for this rule for more details.)
EPA would like to use this occasion to make some observations about
central tendency estimates. There is a common misperception that the
central tendency estimate might be an ``unbiased'' or ``best'' estimate
of risk. That could be extremely misleading, especially where it is
difficult to distinguish variation and uncertainty. The 50th percentile
estimates in the EPA groundwater Monte Carlo risk assessment used to
support listing determinations under RCRA strive to be estimates of
results for which half of the potentially exposed receptors face more
risk and half face less risk in some group. However, that does not mean
that such an estimate is a ``best estimate'' of a relevant result. As
an example, consider if EPA did Monte Carlo estimates of groundwater
risk at all wells in a 360 degree direction from a unit. In many cases
(notably those with a fairly constant direction of groundwater flow
relevant to any upgradient wells), well over half of the wells within
any distance of the unit will be unaffected by releases from the unit
and will have no risk. This would occur no matter what the toxicity or
mobility of the hazardous constituent, and even though deterministic
modeling might show with high certainty that wells in the direction of
groundwater flow from the unit would have high risk. Clearly a central
tendency estimate of ``no risk'' is not a ``best'' estimate of whether
or not there will be groundwater risks, nor even a predictor of
``mean'' risk or of the ``expected value'' risk. Instead, it gives an
indication that there is considerable variation and that many or most
wells will not be affected. That indication would not give EPA any
confidence that a hazardous constituent would not have significant
effect on the downgradient wells, nor any particularly useful
information on the toxicity or mobility of the waste.
Monte Carlo Versus Deterministic Analysis
Two commenters felt that the deterministic high-end risk assessment
used by EPA does not allow EPA to determine what percentile of the risk
distribution is represented by the high-end analysis. In response, EPA
performed a Monte Carlo groundwater analysis to generate probability
distributions for risk presented by each waste. These results were
presented in the NODA, and revised Monte Carlo analyses, using the
revised inputs for landfill area and lifetime, are given in Table IV-2.
Several commenters recommended that the Monte Carlo analysis serve
as the basis for a listing decision, due to the superior quality of the
Monte Carlo-based risk estimates in comparison to the deterministic
risk estimates (i.e., point estimates). They noted that in the NODA,
EPA states that the Monte Carlo analysis ``confirms'' the risk findings
(62 FR 16750-51); the commenters disagree with this approach and state
the Monte Carlo results should be used as the primary determinant of
individual risk. The commenters cite EPA guidance that has recognized
the superior quality of Monte Carlo-based risk estimates compared to
high-end approaches.
In response, EPA notes that the Agency's ``Policy for Use of
Probabilistic Analysis in Risk Assessment'' states that ``* * * such
probabilistic analysis techniques as Monte Carlo analysis, given
adequate supporting data and credible assumptions, can be viable
statistical tools for analyzing variability and uncertainty in risk
assessments.'' The policy also states that ``[i]t is not the intent of
this policy to recommend that probabilistic analysis be conducted for
all risk assessments supporting risk management decisions.'' In
addition, as one of the conditions for using Monte Carlo analysis, the
policy states that ``[c]alculations of exposures and risks using
deterministic methods are to be reported if possible.'' Thus, the
commenter's contention that information from Monte Carlo analysis is
necessary to make a defensible listing determination is over broad and
is inconsistent with Agency policy. The Agency's policy indicates that
Monte Carlo analysis can be a useful tool for providing additional
information on variability and uncertainty in certain situations (which
is the way it was applied for this listing determination).
Furthermore, it is important to note that the Agency's policies do
not indicate that there is any particular point on a Monte Carlo
distribution that should be the point at which the Agency regulates or
does not regulate. The 1992 guidance (memorandum from the then Deputy
Administrator F. Henry Habicht ``Guidance on Risk Characterization for
Risk Managers and Risk Assessors'') states that ``[t]he `high end' of
the risk distribution [generally the area of concern for risk managers]
is conceptually above the 90th percentile of the actual (either
measured or estimated) distribution. This conceptual range is not meant
to precisely define the limits of this descriptor, but should be used
by the assessor as a target range for characterizing `high-end risk'.''
Therefore, a high-end estimate that falls within the range (above the
90th percentile but still realistically on the distribution) is a
reasonable basis for a decision.
Exposure Duration
One commenter questioned why the groundwater risk analysis used a
constant exposure duration of 9 years for receptors, while the
nongroundwater risk analysis for LTUs included this parameter in the
sensitivity analysis and used a high-end value of 30 years. The
commenter submitted modeling analysis that purported to show that
including exposure duration as a high-end parameter in the sensitivity
analysis would result in increased groundwater risks, and specifically
cited increased risks for crude oil tank sediment and unleaded gasoline
tank sediment.
EPA does not agree that exposure duration is a particularly
sensitive parameter in the analyses at issue. In the sensitivity
analysis using exposure duration presented in the commenter's
groundwater analysis, 30-year exposure risks appear to be erroneously
calculated by simply multiplying the calculated 9-year exposure
groundwater risk by a factor of 3.33, corresponding to the ratio of 30
years/9 years. However, EPA's risks based on a 9-year exposure duration
were calculated from the peak well concentrations averaged over a 9-
year period, using health-based numbers derived for a 9-year exposure
period. The more accurate approach to model 30-year exposure would be
to calculate maximum 30-year average groundwater concentrations from
the modeling results, and then calculate the risk based on health-based
numbers derived for a 30-year exposure period. Maximum 30-year average
well concentrations may be smaller than 9-year average well
concentrations depending on the peak concentration period. The
commenter's apparent approach of simply scaling up risks based on a 9-
year exposure by a factor of 3.33 will likely overestimate the
extrapolated risk for a 30-year exposure. EPA examined the effect of
including exposure duration as an independent parameter in a
sensitivity analysis for several wastes (HF alkylation sludge, unleaded
gasoline tank sediment, and hydrorefining catalyst). The results of the
analysis
[[Page 42144]]
showed that exposure duration was never a sensitive parameter, and
including it in the sensitivity analysis had no impact on the selection
of the two high-end parameters or the risk results for any of the
wastes examined (see Section 3 of Additional Groundwater Pathway Risk
Analyses, 1998). Therefore, EPA does not believe this factor greatly
affects the risk calculations conducted for this rulemaking.
Potential for Release of Oil Phase From Wastes
One commenter believed EPA inappropriately discounted the potential
for migration of nonaqueous-phase liquids (NAPLs) arising from free oil
in the wastes to the groundwater zone beneath the waste units. (Note
that NAPLs that sink in water because they are more dense are called
DNAPLs, while NAPLs that float because they are lighter than water are
called LNAPLs). The commenter argued that EPA underestimated risk by
evaluating management conditions unfavorable for NAPL release from
landfills. The commenter also stated that EPA ignored the impact of
this oil phase, or NAPL, on transport of waste constituents in the
groundwater zone to the receptor well. EPA's evaluation in the proposed
rule had concluded that the NAPL flow, if any, from these residuals
will not reach the underlying aquifer and thus further modeling was not
necessary. The commenter argues that EPA underestimated the fraction of
oily liquid in the waste (suggesting a value of 80 percent), falsely
assumed that the waste will be uniformly mixed with benign material
that would not contribute to free oil, overestimated the capacity of
the soil beneath the landfill (the unsaturated zone) to retain oil
released from the landfill, and failed to consider the potential
movement of the oil sideways in the subsurface.
EPA does not agree with the commenter's assertions. First, EPA
notes that the its analysis assumed a 27 percent free oil content in
the waste for its initial calculations, based on data from the 3007
Questionnaire. This is more realistic than the value of 80 percent
cited by the commenter, because the 80 percent value resulted from an
error in reporting. The 80 percent value represents the waste prior to
deoiling, and does not reflect the oil content of wastes in landfills
(see Supplemental Background Document-Listing Support Analysis, April
1997 in the docket, App. A). The Agency used EPA's Composite Model for
Oily Waste (EPACMOW), which accounts for both aqueous phase and non-
aqueous phase flow and transport, to estimate constituent transport.
High-end parameters were chosen for sensitive parameters (landfill
area, waste quantity, waste fraction, constituent concentration, and
infiltration rate). Thus, even assuming the oil fraction is free to
migrate, the model predicted no release of NAPL from the landfill,
because there is not sufficient oil to saturate the material in the
landfill beyond the 10 percent soil or waste saturation limit. Below
this limit the oil will not migrate as a NAPL. If the oil does not
escape the landfill, the NAPL cannot saturate the soil beneath the
landfill, nor can NAPL-facilitated transport in the subsurface occur.
EPA believes the commenter's concerns about NAPL or free-oil
release from landfills are unwarranted for a more fundamental reason.
As discussed elsewhere (see Sampling and Analysis of Refinery Wastes),
the residuals of concern are not oily in the manner anticipated by the
commenter. While the sampled residuals may contain oil, this
observation is not equivalent with concluding, as the commenter does,
that free oil is present in these residuals. The method used to
estimate oil content in the samples, the Total Oil and Grease (TOG)
method, will overestimate ``free'' oil because it uses a strong organic
solvent to extract various organic material, including waxes, greases,
and higher molecular weight oils that are not mobile. During EPA's
observation and handling of crude oil storage tank sediment during
sampling and laboratory analysis, a discrete free oil phase, was not
observed. None of the samples analyzed via the TCLP in this
investigation were found to have oily phases. In addition, as noted
elsewhere, reported oil and grease content of landfilled wastes support
EPA's conclusion that wastes with high oil content (whether free oil or
not) are not typically land disposed. This result is consistent with
EPA's belief that oil concentrations in a landfill will not reach the
levels the commenter suggested, since refineries generally have
economic incentives to recover free oil and minimize the amount of oil
that is disposed in wastes.
The commenter also submitted a report to document the plausibility
of NAPL flow of contaminants from waste management areas (``Release of
Dense Nonaqueous-Phase Liquids to Groundwater in Waste Disposal Areas:
Part 1,'' March 1997). The commenter stated that the report showed four
waste management facilities ``associated'' with the petroleum sector
may have released nonaqueous phase liquids, or oil, into the
groundwater. The commenter concluded that refinery wastes like those at
issue in this rulemaking were codisposed with other wastes in the
units, and may have caused the NAPL or oil release.
EPA disagrees that the report cited by the commenter provides any
information relevant to either the wastes under examination in this
rule, or the type of landfill disposal at issue. EPA evaluated the
report cited by the commenter and does not believe the information is
particularly relevant to the listing decisions under consideration for
several reasons. First, of the 26 sites identified in the report as
having ``definite'' DNAPL contamination, 24 were Superfund sites listed
on the National Priority List (NPL) for remediation. This limited
number of NPL sites represented various industrial sites, many having a
long history of many forms of waste mismanagement beyond landfilling
(e.g., land spreading, land disposal of liquids, surface impoundments).
As such, these sites can hardly be deemed to represent typical off-site
landfills. Furthermore, the four facilities ``associated'' with the
petroleum sector all operated from the late 1950s and most ceased
operation by the early 1970s (one operated until 1981). Not
surprisingly, the types of waste disposal that occurred at these four
facilities do not resemble the typical disposal that occurs presently
at landfills. The report shows (see Table A-3) that all of these
facilities disposed of liquid wastes and sludges in surface
impoundments; other liquid disposal practices included dumping into
trenches and buried barrel mounds. In fact, from the information in the
report it is not clear that any of the four sites had any unit
resembling a solid waste landfill.
In addition, the four sites accepted a variety of wastes, including
chlorinated solvents and other organic wastes (see Table A-2 in the
report). While two sites were reported to receive wastes from tanks
(``wastes from tank cleaning'' and ``tank bottom sludge''), there is no
evidence presented in the report to support the commenter's assertion
that any wastes were similar to the wastes at issue in this rulemaking.
In fact, given the apparent predominance of disposal of liquids at
these two sites, and the lack of any mention of a landfill, it does not
appear likely that the wastes cited resemble the wastes under
evaluation in today's rule. As noted previously, the listing residuals
of concern here did not exhibit free oil, and the available data
indicate that residuals sent to landfills had low total oil content.
Certainly the samples of tank sediments obtained by EPA were not
liquids. Therefore, EPA
[[Page 42145]]
believes that this report does not demonstrate anything significant,
beyond the general fact that some landfills in the past have contained
wastes that may release NAPLs. However, it provides no useful
information about the wastes under study and their potential for NAPL
formation, in either on-site or off-site disposal. EPA does not believe
the information is particularly relevant to the listing decisions under
consideration.
Existing Groundwater Contamination
One commenter stated that the subsurface under many refineries is
grossly contaminated, and may affect the rulemaking in two important
ways: (1) existing subsurface contamination can contribute
significantly to groundwater risks at the modeled receptor well near
refinery sites, thus EPA should include the cumulative risks in its
assessments; and (2) the existing refinery groundwater contamination is
often in the form of LNAPL (such phases float on top of the groundwater
and typically contain lower molecular weight constituents, such as
those found in gasoline) or other conditions that can facilitate the
transport of organic contaminants at refinery sites, including but not
limited to the PAHs in refinery wastes. The commenter noted that the
rate and extent of LNAPL migration can depend upon site-specific
circumstances, and often results in lower dilution and attenuation, and
could result in higher concentrations at a receptor well. The commenter
stated that while there is no nationwide survey of LNAPL occurrence at
refinery sites, there is ample evidence that LNAPL contamination is
frequent and severe, and EPA must take into account the hydrogeologic
conditions known to the Agency that can affect the transport of
hazardous constituents. However, the commenter did not offer any
suggestions as to how to consider such ``facilitated transport'' in the
groundwater assessment.
EPA agrees that there are no doubt petroleum refineries at which
significant LNAPL contamination from product spills exist; however the
Agency does not believe this should have a significant impact on its
listing decisions for several reasons. First, EPA's risk assessment is
conservative in that it assesses incremental risk associated with
targeted residuals using a relatively low 10-5 to 10-6 risk listing
threshold, in part because of possible exposure to unknown pollutants.
Furthermore, EPA cannot conclude that LNAPLs would be present at the
precise sites where these wastes are likely to be disposed and
potentially release constituents. As the commenter also noted, the rate
and extent of NAPL migration can depend upon site-specific
circumstances. The proper consideration of existing contamination would
call for the full analysis of many other site-specific factors as well,
some of which may tend to reduce constituent release from landfills,
subsurface transport, and human exposure. Such factors would include
the possible lack of potable groundwater near the site, and potential
biodegradation at some sites, perhaps accelerated due to the prevalence
of subsurface organisms that may exist in areas with contamination.
Further, if LNAPL or other contamination exists, there may well be
ongoing remediation, perhaps involving groundwater interception or
pumping that would significantly alter or limit groundwater flow. The
Agency believes that a site-specific assessment would be more
appropriately carried out by State or Federal programs related to
remediation of sites, and that such an approach would be quite
difficult to follow in pursuit of an industry-wide listing
determination.
EPA also notes that it is not likely that aquifers so widely
contaminated so as to have floating hydrocarbons would be a continuing
source of drinking water. Such contamination should be easily detected
and avoided, and would be unlikely to lead to the multiple-year
transport and exposure scenario that is the basis for EPA's risk
assessments. Furthermore, the level of benzene in likely sources of
LNAPLs, gasoline (1.6 percent average, or 16,000 ppm), would dwarf any
potential risk that might arise from the leachable levels of benzene in
wastes under consideration in this rule, making any concept of
cumulative risk difficult to apply in any meaningful way in a listing
determination. (For comparison, the highest level of benzene in any
TCLP sample of listing residual was 39 ppm for hydrotreating
catalysts). As noted above, the commenter's approach also presumes a
number of additional worst-case assumptions (regarding the presence of
critically placed NAPLs) that cannot be considered in a vacuum, and
would require the consideration of many other site-specific factors to
fully evaluate.
The Agency notes that the practical impact of considering LNAPLs
and facilitated transport, even if this could be done, is not likely to
be significant for most wastes of concern. EPA has decided to list the
wastes with higher oil content (CSO tank sediment and crude oil tank
sediment), as well as the spent catalysts. Thus, the wastes for which
this comment is most relevant are being listed, leaving unleaded
gasoline tank sediment and HF alkylation sludge as the only other
wastes that showed any groundwater risk of concern to the commenter.
EPA notes that the effective dilution and attenuation factors for
benzene resulting from the modeling (DAF; calculated by dividing the
TCLP input at the point of release from the landfill by the projected
concentration at the receptor well) for both of these wastes were on
the order of 2 to 4 (see Additional Groundwater Pathway Analysis,
1998). These low DAFs approach the theoretical limit of one, which mean
that benzene released from the landfill is estimated to reach the
receptor well at concentrations that approach the levels in leachate
released. Therefore, it is highly unlikely that EPA's assessment
significantly understates groundwater risks for these wastes, and any
further considerations in the modeling (such as ``facilitated
transport'' due to existing contamination) are unlikely to
significantly alter the modeling results.
Unlike the modeling for benzene, which is relatively mobile in
groundwater, the limited modeling for PAHs detected in TCLP samples
indicates that contaminated subsurfaces may have the potential to
affect the migration of PAHs in groundwater. PAHs are relatively
insoluble in water and are not expected to migrate easily via aqueous
leaching and transport, and the high-end analysis for the PAH
benz(a)anthracene showed DAFs of 15-64 (see Additional Groundwater
Pathway Analysis, 1998). As the commenter noted, the presence of
existing contamination such as NAPLs in the subsurface may facilitate
migration. Some oily wastes contained potentially significant levels of
PAHs (CSO sediment, crude oil storage tank sediment), and while TCLP
results showed no detectable leaching, the detection limits in these
samples were above health-based levels. It is difficult to assess
potential groundwater risks from PAHs with complete certainty because
undetected but potentially significant levels might possibly be in the
TCLP leachate. PAHs could theoretically present some risk if they
leached at their aqueous solubility levels, which in many cases are
below detection limits. For example, the water solubility of
benz(a)anthracene (0.013 mg/L) is 32 times the health-based level (4E-4
mg/L at the 1E-6 risk level), and this level is very close to the
method detection limit (about 0.010 mg/L). While EPA cannot quantify
any risks from TCLP samples in which PAHs
[[Page 42146]]
were not detected, the presence of these carcinogenic PAHs in the waste
present some potential for additional risk, especially if transport is
facilitated by existing contamination. Therefore, while EPA is not
using the presence of carcinogenic PAHs as the sole or overriding
factor in listing any waste (except for CSO sediment which clearly
exhibited high risks from nongroundwater pathways due to PAHs), the
presence or absence of carcinogenic PAHs was a contributing factor EPA
considered in decisions to list or not list certain wastes (i.e., crude
oil storage tank sediment, unleaded gasoline tank sediment, and HF
alkylation sludge. However, EPA would not list solely on the
undetermined potential for groundwater risks from PAHs given their
relative insolubility, and because facilitated transport by LNAPLs is a
complex hypothesis that EPA did not find likely for these particular
wastes.
7. Specific Nongroundwater Modeling Issues
Uncertainty Analyses in Indirect Exposure Assessment
For both the proposed rule and the NODA, estimates of non-
groundwater pathway risks were derived using a deterministic risk
assessment method, which produces point estimates of risk using single
values for input parameters. In this method, input parameters are
varied between the central tendency value (50th percentile) and the
high-end (90th percentile) values. The point estimate in which all
variables are set at central tendency is assumed to be the central
tendency risk estimate, and the highest risk estimate for any
combination of double high-end variables (with all other variables set
at central tendency) is assumed to be the high-end estimate of risk.
The high-end risk estimate is presumed by the Agency to be a plausible
estimate of individual risk for those persons at the upper end of the
risk distribution. The intent of these descriptors is to convey
estimates of exposure in the upper end of the distribution (i.e., above
the 90th percentile), while avoiding estimates that are beyond the true
distribution. The high-end risk as estimated in the proposed rule and
NODA is the highest risk estimate for any combination of double high-
end variables defined as those two variables modeled that, when set at
90th percentile values, pose the highest risk of all possible
combinations of any two variables. Using this methodology, the point
estimate in which all variables are set at central tendency (50th
percentile) is assumed to be the central tendency risk estimate, and
the highest risk estimate for any combination of double high-end
variables is assumed to be the high-end estimate of risk (above the
90th percentile; see Agency guidance in the Habicht memo, 1992).
The Agency requested comments on how best to factor uncertainty
into Agency listing determinations based on the non-groundwater risk
assessment. These risk assessments are so-called ``indirect'' exposure
assessments, and are discussed in the proposed rule preamble at 60 FR
57762. Indirect exposure assessments are those in which the receptors
(in this case nearby residents, home gardeners, subsistence farmers and
subsistence fishers) are exposed to contaminants in the waste after
these contaminants have been transported from the waste management area
and have entered another environmental media (in this case soil and
various food products) at the receptor site. This issue is important
for this rule because the potential exposure pathways of concern arose
from releases of soils through erosion (run-off) or wind-blown air
emissions from LTUs onto adjacent areas.
Of particular concern to the Agency in the proposal was the issue
of whether it is accurate to assume that greater uncertainty generally
results in a more conservative risk assessment. One commenter noted
that because the uncertainty in indirect exposure assessment can lead
to a substantial overestimation of risks, failure to consider
uncertainty can result in listing decisions for refining process
residuals that do not actually pose a significant risk. The commenter
suggested that EPA could account for uncertainty in indirect exposure
assessment through a quantitative probabilistic uncertainty analysis,
or to list those wastes associated with substantial uncertainty only if
the estimated risks are at the high-end of the risk range.
Other commenters questioned the use of individual assumptions or
input parameters in the nongroundwater risk assessment for LTUs.
Commenters specifically noted that EPA should include a quantitative
analysis of the following sources of uncertainty in the risk estimates
for residuals proposed for listing: biotransfer factors, food
consumption rates, biodegradation, land application rates, and physical
transport processes.
The Agency agrees that an uncertainty analysis is desirable and
conducted an uncertainty and variability analysis in support of the
final nongroundwater risk assessment. The Agency addressed specific
comments regarding use of individual parameters (e.g., biodegradation
rates) by including those parameters in the uncertainty analysis. A
detailed description of the uncertainty analysis is presented in the
document titled Uncertainty Analysis: Nongroundwater Pathway Risk
Assessment; Petroleum Refining Waste Listing Determination available in
the docket for today's rule. This document identifies the source of
uncertainty or variability noted by commenters in each step of the
analysis and describes the method of quantifying or mitigating that
uncertainty/variability. When data distributions were available,
variable parameters were included in a Monte Carlo simulation to
provide a quantitative measure. If little or no data were available, a
qualitative discussion of the source and effect of the uncertainty is
provided. Key variables included in the uncertainty analysis include:
constituent concentrations, biodegradation rates, distance to receptor,
soil erosion parameters, bioaccumulation factors and bioaccumulation
rates, and ingestion and consumption rates. The uncertainty associated
with the generalized site assumptions of LTU area, waste quantity, and
geographic location used in the deterministic analysis was addressed
through the use of site-specific data where available.
The nongroundwater assessment uncertainty analysis covers three
waste streams: CSO sediment, crude oil storage tank sediment, and off-
specification products and fines. These were the only wastes with
moderate to high levels of carcinogenic PAHs, and because PAHs were the
constituents of concern for LTU risks, the risks for other wastes in
this scenario were negligible (see 62 FR at 16753). EPA proposed CSO
sediment for listing on the basis of the nongroundwater deterministic
(high-end) analysis, which showed significant risk from PAHs. Crude oil
storage tank sediment, which contains similar constituents in lower
concentrations, showed risk levels from land treatment below EPA's
range of concern. Off-specification products and fines also have
similar constituents present in lower concentrations, but were not
originally modeled as managed in LTUs for the proposal because the
volumes managed this way were relatively small. However, off-
specification product and fines were modeled as part of the LTU
analysis conducted for the NODA to respond to comments on potential
risks arising from codisposal. (See Section V.C.6 for a full discussion
of the decision on off-specification products and fines).
[[Page 42147]]
The probabilistic uncertainty analysis was performed on a
constituent specific basis, thus comparisons between the Monte Carlo
and the high-end results must be made for a specific constituent to be
meaningful. For example, for clarified slurry oil sediment managed on-
site, the high-end risk analysis estimated a risk of 5E-5 to the
subsistence farmer from dibenz(a,h)anthracene via oral ingestion
pathways. The uncertainty analysis for on-site management of clarified
slurry oil sediment indicated a 90th percentile risk to the farmer from
dibenz(a,h)anthracene via oral ingestion of 5E-5 for the site modeled
(Anacortes, WA). For CSO managed off-site, the high-end ingestion
pathway risk to the farmer from dibenz(a,h)anthracene was estimated to
be 2E-6. Based on the probabilistic analysis, the corresponding 90th
percentile risk for this waste stream was 3E-6 and 1E-5, respectively,
for the two off-site LTUs modeled (Robstown, TX and White Castle, LA).
For both crude oil storage tank sediment and off-specification products
and fines, the uncertainty analysis indicates that risks are below 1E-5
at the 90th and 95th percentiles for all exposure scenarios associated
with on-and off-site management of these waste streams in LTUs,
consistent with the high-end deterministic results.
The uncertainty analysis confirms that the high-end risk results
presented in the NODA are plausible estimates of risk for individuals
at the upper end of the risk distribution. In the high-end analysis
presented in the NODA, the total carcinogenic risk (i.e., the combined
risk from all of the hazardous constituents) for this waste was 2E-4, a
level well above EPA's benchmark level of concern (1E-5). For the on-
site CSO scenario, the uncertainty analysis indicates risks of 1E-5
from individual constituents at the 90th percentile of the risk
distribution. Thus, the uncertainty analysis indicates that on-site
high-end risks for CSO from individual hazardous constituents clearly
do not represent risks that are outside of the true distribution.
Rather, the probabilistic analysis indicates that high-end risks for
individual hazardous constituents in some cases represent exposure
below the 90th percentile of the risk distribution.
The total carcinogenic high-end risk for CSO for off-site units was
2E-5. For this waste management scenario, the uncertainty analysis
indicates risks of 1E-5 from a single constituent at well below the
90th percentile. The off-site probabilistic analysis also suggests that
the high-end risks may be somewhat below the 90th percentile for this
scenario.
Based on the results of the uncertainty analysis, therefore, the
deterministic analysis certainly does not appear to overestimate risks
from CSO. In any case, the decision to list CSO sediment is clearly
supported by the uncertainty analysis. The Monte Carlo risk results
below 1E-5 under all conditions for crude oil storage tank sediment and
off-specification product and fines also confirms the decision not to
list these wastes based on nongroundwater risks (note that EPA has
decided to list crude oil storage tank sediment based on groundwater
risks from landfill disposal).
Run-on/Run-off Controls
EPA received numerous comments regarding the use of run-on/run-off
controls for LTUs, which indicated that there was some confusion about
EPA's assumptions regarding these controls in the risk assessment. The
proposed listing determinations (as well as today's final decision)
assumed no controls for the high-end analysis, and 50 percent effective
controls for the central tendency analyses. Commenters challenged these
assumptions as outlined below.
Two commenters argue that there is no legal or factual foundation
for the Agency's assumption that any plausible mismanagement involving
land treatment now or in the future will occur at a facility with run-
off controls, much less with controls achieving 50 percent efficiency.
Conversely, seven commenters state that even where there are no
Subtitle C or mandatory state Subtitle D regulatory requirements for
these controls, numerous other factors are motivating their use, as
evidenced by the fact that most facilities use them.
EPA conservatively assumed that no run-off controls were present in
its high-end analysis of risk to individuals residing near land
treatment facilities because the presence and effectiveness of such
controls could not be verified. The central tendency scenario, however,
assumed that controls were in place that were 50 percent effective.
After consideration of all comments and the available data, EPA did not
change these assumptions in subsequent risk assessments for the NODA.
The bases for these assumptions were responses to the 3007
Questionnaire and a survey of State programs. In the 3007
Questionnaire, refineries were asked to characterize whether run-on or
run-off controls were in place at LTUs used in 1992. Based on this
information, all of the 18 facilities with LTUs reported some level of
controls. As part of the revised risks analysis for LTUs presented in
the NODA, EPA determined all but 6 LTUs are permitted Subtitle C units,
and thus required to have run-on/run-off controls (see 40 CFR 264.273).
For the nonhazardous units, it was not possible to quantify the
effectiveness of the controls due to the very general nature of the
questions and responses.
EPA's survey of State programs showed that, while some states have
established minimum standards for Subtitle D units, many states do not
have regulations on run-on/run-off controls (see Communications with
State Authorities on Requirements for Land treatment Units, EPA, 1995;
Docket # F-95-PRLP-S0019). The effectiveness of run-off control is
dependant on many factors (e.g., level of engineering design, operation
and maintenance practices, regulatory oversight and minimum standards,
weather conditions), and the effectiveness may vary because of the lack
of Federal nonhazardous LTU standards. As a result, EPA assumed only
partial effectiveness, 50 percent controls, for the central tendency
analysis, and no controls for the high-end analysis. EPA does not have
data available that would allow for more precise quantification of
effectiveness. The Listing Program's mandate to consider potential
mismanagement scenarios clearly does not rely on assumption of the best
controls, but rather must more closely evaluate the weakest plausible
management scenarios. In the case of LTUs, this includes the potential
for no or minimal run-on or run-off controls in many states, reflecting
the lack of national minimum standards. (EPA notes that, in the revised
NODA analysis, the Agency did not use LTU areas for hazardous waste
units in its risk assessment, because these units are assumed to have
effective controls in place. This information would not be applicable
to estimating risks for nonhazardous LTUs).
Furthermore, EPA notes that the risks arising from soil run-off
have limited impact on the Agency's final listing decisions based on
the outcome of the risk for the nongroundwater pathways. This is
because EPA has discovered that, due to an error in the air dispersion
modeling conducted for the proposal, the risk attributable to the air
pathway has increased and is now the same order of magnitude as the
risk due to soil erosion. (The error was in converting units from
g/m\2\ to g/m\2\). The unit conversion correction makes the
risk due to air deposition from windblown soil from the LTU comparable
to the risk
[[Page 42148]]
attributed to soil erosion. For example, for on-site LTU risk for CSO
sediment, the total carcinogenic risk due to soil transport is 1E-4.
The risk due to air deposition is approximately 7E-5, and the risk from
soil run-off is about 3E-5 (see the NODA response to comment document
for a more detailed discussion). Thus, soil erosion and run-off control
assumptions are not as critical for the listing determination, because
even in the absence of exposure through run-off, the risks for this
waste are well above 1E-5 and merit listing. The relative contributions
to the media concentrations of contaminants from air and erosion were
investigated in the uncertainty analysis conducted in support of this
listing determination.
Soil Transport
EPA received numerous comments to both the proposed rule and the
NODA questioning the methodology used to estimate soil run-off and
transport from an LTU to surrounding fields and water bodies.
Commenters to the proposal stated that transport of soil from the land
treatment area to the receptors was not physically possible as modeled
by EPA's use of the Universal Soil Loss Equation (USLE).
The USLE is an empirical erosion model originally designed to
estimate average soil erosion losses to waterbodies from an
agricultural field having uniform slope, soil type, vegetative cover,
and erosion control practices. In the proposed risk assessment, the
USLE was used to estimate the mass of soil lost per year per unit area
from a LTU and deposited onto an adjacent receptor site. EPA estimated
the percentage of the eroded soil that reached the receptor site using
a fixed sediment delivery ratio. The Agency estimated the amount of
soil eroded from the LTU and deposited on each receptor site
(agricultural field, residential lot, home garden) independently of
soil eroded and deposited into the nearby waterbody.
In response to comments on the proposed rule, EPA substantially
revised its approach to estimating soil concentrations. This approach
is presented in the NODA. Revisions were made to more accurately model
an integrated soil erosion setting that includes the field, a buffer
zone and the water body. The revised method for estimating soil erosion
incorporates mass balance assumptions within the field to stream
setting, and places the receptor field between the landfill and the
waterbody. The model estimates rate of soil delivery to the nearest
waterbody and assumes that the soil eroded from the source that does
not reach the stream is deposited evenly over the subbasin, including
the garden.
Commenters on the NODA regarding EPA's use of USLE to estimate soil
erosion centered on the assertion that run-off after leaving the land
treatment area does not flow uniformly across the landscape, but will
instead flow in a ``channel'' moving downstream toward the outlet of
the basin or watershed. A number of commenters also argued that EPA's
assumption of receptor locations relative to LTUs is unreasonable. They
noted that EPA assumed that residences are directly downgradient of
LTUs and that there are no obstructions to flow, when in fact the
existence of a ditch, fence, wooded area, road, building, or swale
between the landfarm and a garden eliminates this pathway of exposure.
Commenters contended that the run-off cannot reach the gardens, farms
and adult residents without unrealistic assumptions regarding location
of receptors. These commenters argued that EPA failed to adequately
respond in the NODA to proposed rule comments that the run-off from an
LTU cannot physically reach the home gardens as assumed and that
therefore the revisions presented in the NODA are inadequate.
EPA's revised method for estimating soil erosion assumes that the
sediment delivery ratio is constant across the area between the LTU and
the waterbody (i.e., it does not assume channeling), and that receptor
sites are assumed to be downgradient from the source and within the
same defined subbasin as the LTU. EPA believes that these assumptions
are reasonable in order to estimate risk that might be expected to
occur at petroleum refining locations. In the absence of specific data,
EPA believes that its assumptions are reasonable and appropriately
conservative, because residential locations may change over time. In
addition, EPA notes that to properly consider channeling in soil
erosion would require extremely detailed site descriptions of the
topography and local conditions, and sufficiently detailed site
descriptions are not available. In the absence of such detailed data,
EPA used simplifying assumptions to estimate soil erosion that may
occur over a wide range of possible scenarios. Furthermore, while the
commenters disputed the modeling approach used by the Agency, they did
not provide any alternative model that could be used with the
information available.
For listing determinations, EPA wants to ensure that its risk
estimates are conservative, and do not underestimate risks from
releases from LTUs containing these wastes. As noted extensively
elsewhere in this Section, other commenters have raised reasons why
EPA's modeling of LTUs may underestimate risks (e.g., existing
contamination around refineries, codisposal with other wastes). EPA
believes that its overall modeling approach for LTUs is an appropriate
middle ground and reflects risks that may arise from such units. The
models used by EPA to develop this rule are exceedingly complex. It
would not be practicable, and likely impossible, to develop models that
would account for all possible sources of site-specific variability.
Accordingly, EPA has used reasonable, simplifying assumptions to
estimate risks.
As described above in the discussion on run-on/run-off controls,
EPA inadvertently made an error in the modeling for the proposed rule
in unit conversion, which created an underestimation of risk due to air
deposition. This change was described in the nongroundwater risk
background document for the NODA. Because the unit conversion
correction makes the risk due to air deposition from windblown soil the
same order of magnitude as the risk attributed to soil erosion, USLE
modeling assumptions do not provide the sole basis for the listing
determination.
Specific comments regarding the individual parameters and
assumptions used in EPA's USLE calculations (e.g., steepness of slope,
soil delivery rate, meteorologic and soil data) are addressed in detail
in the response to comment documents for the proposal and the NODA. In
addition, the modeling conducted as part of the uncertainty and
variability analysis for LTUs included site-specific meteorologic data,
soil data, USLE parameter values, and the distance between the LTU and
the home gardener receptor. This analysis has shown that the listing
decision is not altered by the use of site-specific data for some of
the parameters questioned, or by variation in the receptor location.
Bioavailability and Bioaccumulation
EPA received a number of comments on the manner in which biological
processes such as bio-uptake, biotransformation, and bioaccumulation
were considered in the non-groundwater risk assessment. One commenter
states that EPA should have, but did not, consider the potential health
effects to subsistence farmers and fishers due to bioaccumulation of
PAHs. The commenter contends that EPA simply ignored this exposure
route for these receptors due to the ``high uncertainty'' associated
with fish and
[[Page 42149]]
plant-to-animal bioconcentration factors for the PAHs of concern in
this rulemaking. The commenter believes that EPA should consider the
information qualitatively, and/or present a range of results based upon
possible bioconcentration factors. EPA responds that the Agency
appropriately considered bioaccumulation of PAHs in these receptors as
discussed below. A more detailed response to this issue is found in the
uncertainty and variability analysis conducted in support of the risk
assessment for this rule.
The subsistence farmer scenarios were evaluated initially for the
proposed rule using beef and milk biotransfer factors for PAHs that
were estimated based on the octanol/water partition coefficient
(KOW). KOW is a measure of the affinity a
chemical has for a nonaqueous, organic environment (octanol), versus
its tendency to stay in water, and is commonly used to assess the
absorption rate of a given compound from the environment into
organisms. Beef and dairy biotransfer factors are used to estimate the
transfer of constituents from the diet of cattle into meat and milk
products consumed by humans. KOW was initially used as a
surrogate for biotransfer because measured data on the biotransfer of
PAHs from plants to cattle or other ruminants are currently
unavailable. However, in the NODA, EPA decided not to use these
estimates in the risk assessment because the Agency believes that use
of KOW greatly overestimates biotransfer for constituents
with large KOWs. This includes the PAHs of concern in
petroleum waste streams.
Estimates of biotransfer based upon KOW only consider
transfer of the constituent from the concentration in the diet into the
concentration in the lipid storage in the animal. These estimates do
not consider metabolic pathways for any constituents. In fact, PAH
compounds with large KOWs are readily metabolized by the
mixed function oxidase metabolic pathway in mammals to water-soluble
substances, which are then excreted. In other words, these PAHs tend
not to bioaccumulate in animal or human tissue, but rather to be
metabolized and excreted.
To summarize, because it is not possible to estimate PAH
biotransfer factors without at least one measured value for any PAH
compound, the Agency did not quantitatively model risks from
bioaccumulation of PAHs for the farmer and child of farmer scenarios.
Rather, based on knowledge of how PAHs with large KOWs are
metabolized in mammals, the Agency has concluded that risk attributable
to the beef and dairy pathway are likely to be less than the risk
attributable to other ingestion pathways for these scenarios. A more
detailed discussion of the metabolic pathways for these constituents is
provided in Section 4.5 of the uncertainty and variability analysis.
Subsistence fisher scenarios were evaluated using measured
bioaccumulation and bioconcentration factors (BAFs and BCFs) where
available. BAFs generally reflect the transfer of contaminant from the
environment to the fish from food sources. BCFs represent the transfer
from the dissolved phase to the fish tissue BCF. Because measured BAFs
are usually not available, BCFs are most often used. For those
constituents for which neither measured BAFs nor BCFs were available,
EPA assumed that BAFs did not exceed 1000 liters per kilogram of fish
body weight (L/kg). This assumption is based on the data presented in
Derivation of Proposed Human Health and Wildlife Bioaccumulation
Factors for the Great Lakes Initiative (U.S. EPA, 1993).
While there are insufficient data to define the distributions and
correlations needed for a reliable Monte Carlo analysis of
bioaccumulation of PAHs in fish, EPA did conduct a quantitative
uncertainty analysis after the NODA for BAFs using interval analysis.
This is an appropriate statistical method for estimating missing values
in a distribution even when data are limited as is the case for BAFs
for PAH.
This analysis indicates that although there is not enough
information to define the distribution and correlations needed for a
reliable Monte Carlo analysis, the estimation of 1,000 l/kg is
appropriate and within the range of uncertainty predicted for PAH
compounds. A more detailed discussion of EPA's assessment of
bioaccumulation of PAHs in fish is provided in Section 4.5 of the
uncertainty analysis for the nongroundwater pathway risk assessment, as
well as in the response to comment document for this rule (see Section
M of the response to comment document for the proposed rule).
One commenter questioned the air-to-plant biotransfer factors (Bv)
used by EPA in the analysis conducted for the proposed rule. The
commenter stated that EPA's calculations of Bv contain errors, and
claimed that EPA did not adequately explain or provide the basis for
its estimate of Bv values. In comments on the NODA, the same commenter
argued EPA continued to overestimate air-to-plant transfer.
EPA responds that the errors noted by the commenter were corrected
in the reanalysis presented in the NODA. The basis for EPA's estimate
of Bv values is as follows. Measured values for air-to-plant
biotransfer factors are available for many PAH constituents. Where
available, EPA used measured values. The remaining Bvs are estimated
from the KOW (using the Bacci equation). As previously
noted, KOW tends to overestimate the bioaccumulation of
constituents with very large KOWs such as PAHs. EPA
compensated for this overestimate by reducing the calculated Bv by a
factor of 40. This approach was first presented in the 1993 Addendum to
Methodology for Assessing Health Risks Associated with Indirect
Exposure to Combustor Emissions (EPA document number EPA/600/AP-93/
003).
One commenter argues that the assumption of 100 percent
bioavailability of deposited constituents is overly conservative
because many constituents, particularly PAHs, bond tightly to soils and
are unlikely to be available to an organism even if the soil is
ingested.
In response, EPA contends that the 100 percent bioavailability
represents a reasonably conservative estimate of risk that will result
in a rule protective of health and the environment. The bioavailability
of PAHs from ingested soil depends on several environmental and
physiologic factors. The process by which ingested soil-bound PAHs are
made more or less bioavailable in the digestive tract and the effect of
soil characteristics are not well understood; study results are
conflicting. A recent study on the oral bioavailability of PAHs from
soil, reported that the oral absorption of PAHs in rats, hamsters, or
humans from diet or oil is approximately 92 percent. Another recent
abstract presented data for the bioavailability of the PAH
benzo(a)pyrene (BaP) from soil in terms of fraction of the BaP in soil
that is absorbed relative to the BaP ingested. Based on that report,
the fraction of BaP absorbed varied from 0.07 to 0.75. (A more detailed
discussion of this issue is provided in Section III.F of the response
to comment document for the proposal in the docket). Due to the
uncertainty regarding the bioavailability of PAHs in soil, the Agency
believes it is appropriate to assume PAHs to be 100 percent
bioavailable in order to be fully protective of human health.
Exposure Factors
Three commenters provided comments on risk to home gardeners from
consumption of contaminated produce. In comments to the proposed rule,
one commenter argued that EPA's estimate of risks from root vegetable
consumption are overestimated by two orders of magnitude. EPA responds
that,
[[Page 42150]]
based on this comment, the ingestion rates used for vegetables consumed
by home gardeners and subsistence farmers were corrected and the
corrected rates were used in the revised risk assessment presented in
the NODA.
Another commenter states that the percentage of the population
assumed to have gardens is overestimated because EPA did not account
for the fact different rates of produce consumption by the home
gardener correspond to different types of gardens. The commenter
contends specifically that EPA's assessment of risk to the home
gardener from CSO sediment is significantly overestimated due to
overestimation of the amount of produce consumed. The commenter states
that EPA should have used data from the National Gardening
Association's 1994-95 survey for assumptions regarding percentage of
the population with vegetable and fruit gardens and fruit and vegetable
ingestion rates.
In response, EPA notes that the exposure factors (e.g., patterns of
fruits and vegetables consumption by home gardeners) used in the
analysis presented in the NODA were obtained from the 1997 Exposure
Factors Handbook, which provides EPA's most recent data on the various
factors used in assessing exposure. Furthermore, EPA addressed the
variability in consumption rates within different subpopulations as a
component of the uncertainty and variability analysis performed after
the NODA. As previously noted, results from the uncertainty and
variability analysis support the findings of the revised high-end risk
analysis presented in the NODA.
Several commenters contend that EPA overestimated soil ingestion.
One commenter asserts that EPA did not account for the fact that
individuals ingest soil in proportion to the time spent at each
location (i.e., away from home, indoors at home, outdoors at home). EPA
responds that variability in soil ingestion rates has also been
addressed in the uncertainty and variability analysis conducted in
support of the risk assessment for this rule. The uncertainty analysis
used data on soil ingestion rates provided in the 1997 Exposure Factors
Handbook.
Background Contamination
One commenter notes that EPA's modeling assumes no background or
other contaminant exposure to nearby receptors, an unjustifiable
assumption given other waste management practices occurring at these
facilities, the pre-existing contamination at many refineries, and the
routine and accidental releases associated with refinery operations.
As EPA noted elsewhere in today's notice when discussing existing
groundwater contamination, the Agency does not believe this is
appropriate to consider for this listing for several reasons. First,
EPA does not have the type of specific information on off-site
contamination that would be required, nor did the commenter provide
any. Furthermore, without extensive site-specific data, EPA cannot
conclude that existing soil contamination would occur at the same off-
site locations that might be impacted by releases from LTUs containing
the wastes under study. The proper consideration of existing
contamination would call for the full analysis of many other site-
specific factors, some of which may reduce constituent release,
transport, bioaccumulation, and exposure. Such factors include specific
LTU design, the direction of any slope from the unit, the existence of
downgradient residential receptors, and corrective action requirements
that may lead to clean up of any release.
Fate, Transport, and Toxicity of PAHs
Commenters to the proposal pointed out that EPA failed to consider
the biodegradation of PAHs in LTUs and at off-site receptor locations,
thus overstating risks from PAHs in soils. One commenter noted that
failure to consider biodegradation of the PAHs, 7,12-
dimethylbenz(a)anthracene ((7-12-DMBA) and 3-methylcholanthrene (3-MC)
in the risk analysis for CSO sediment resulted in the overestimation of
risks, because these two compounds have high cancer slope factors.
While biodegradation of PAHs within LTUs was considered in the analysis
for the proposed listing, biodegradation that may occur during
transport of soil from the LTU to the receptor location was not
considered in that assessment.
EPA agrees that biodegradation during transport may be a
significant removal process for PAHs and should be considered in
analysis of PAH fate and transport. Therefore, in response to this
comment, the nongroundwater risk analysis conducted for the NODA was
expanded to include biodegradation of PAHs (including 7,12-DMBA and 3-
MC) at the receptor location for the waste streams of concern. Detailed
results of this analysis are provided in the revised risk assessment
technical background document in the docket for the NODA. The
reanalysis presented in the NODA did not significantly change the risk
estimates for these waste streams; however, because some of the PAHs
have relatively long half-lives (e.g., 3-methyl cholanthrene's half-
life is reported to be from 1.67 to 3.84 years) so they are unlikely to
biodegrade significantly prior to reaching the receptor.
Contrary to the commenter's prediction, consideration of
biodegradation at the receptor did not result in reduction of risk
estimated for CSO sediment. For example, based on the analysis for the
proposed rule, the high-end cancer risk for the home gardener scenario
from CSO sediment managed on-site was estimated to be 9E-5. Based on
the NODA analysis, high-end risks for this scenario were estimated to
be 1E-4.
For the analysis conducted for the NODA, EPA used only the most
conservative value for biodegradation rates in order to assure that
biodegradation is not overestimated when conditions and locations are
not ideal for biodegradation. However, biodegradation rates were varied
as part of EPA's analysis of the uncertainty and variability associated
with non-groundwater risk assessment presented in the NODA. As
discussed above, the results of the uncertainty/variability analysis
support the findings of the revised high-end risk analysis presented in
the NODA.
C. Residual-Specific Comments
The most important risk and modeling issues raised by commenters
that were general in nature, or were raised repeatedly for various
wastes, are addressed in the preceding section. Below EPA discusses
specific comments important for individual wastes and presents the
Agency's rationale for the final listing decisions.
1. Crude Oil Storage Tank Sediment
Summary
EPA is listing as hazardous crude oil storage tank sediment from
petroleum refinery operations. This waste stream meets the criteria set
out at 40 CFR 261.11(a)(3) for listing a waste as hazardous, because it
may pose a substantial or potential hazard to human health or the
environment. The Agency has identified substantial risks to consumers
of groundwater associated with releases from off-site Subtitle D
landfilling due to benzene, which EPA has decided will not be
adequately regulated under the TC. The revised groundwater risk
assessment results are summarized in Table IV-2.
Discussion
The Agency proposed not to list as hazardous tank sediment from the
[[Page 42151]]
storage of crude oil at petroleum refineries, either on-site or at tank
farms owned by or affiliated with the refineries or refinery companies.
In the proposal, the Agency found risks at levels of potential concern
(3E-5, high-end groundwater risk) associated with disposal in off-site
landfills; however EPA believed that because the only constituent of
concern, benzene, is already regulated under the TC, listing might not
have been warranted. See 60 FR 57763. The proposal also reported low
risks from carcinogenic PAHs potentially released from land treatment
operations (60 FR 57762). The Agency solicited comment on the decision
not to list this waste stream, particularly on whether the TC captures
wastes of concern, whether the Agency adequately characterized the risk
for this waste, and whether any other factors should be considered.
The revised risk analysis presented in the NODA for land treatment
continues to show insignificant risks (<1E-6) for this residual, and
EPA did not conduct any further analysis on this management scenario.
The high-end groundwater risks from the NODA analysis for landfills
were essentially unchanged. Also in the NODA, EPA presented risk
results to assess the potential impact of the TC regulation, (i.e.,
input levels to the groundwater model were capped at the TC regulatory
levels) assuming that wastes above this level would be properly handled
as hazardous. The TC-capping reduced the risks only slightly (2E-5). In
addition, EPA provided a Monte Carlo analysis of the groundwater risks
that were somewhat lower than the high-end risk at the 95th percentile
(5E-6), but comparable at the 99th percentile (4E-5).
In response to comments on the NODA, the Agency further revised the
input data for the groundwater pathway analysis as noted elsewhere in
this notice. As shown in Table IV-2, this final groundwater pathway
analysis showed slightly higher high-end risks (4E-5) and Monte Carlo
risks (1E-5 and 5E-5 at the 95th and 99th percentiles). As in the NODA
analysis, the risks estimated with benzene input capped at the TC level
were only slightly lower for the high-end analysis (3E-5) and Monte
Carlo results (9E-6 and 2E-5 at the 95th and 99th percentiles).
Following careful consideration, the Agency has decided not to rely
on the TC to control the risks for crude oil tank sediment, because, as
the TC-capped results suggest (risk up to 3E-5), the TC may not fully
capture benzene risks for this waste. Thus, even assuming refineries
properly handle wastes above the TC level, wastes below this level may
present risk above 1E-5. Furthermore, this sediment waste appears to be
stratified as it forms in the tank, and upper layers are often
centrifuged to remove oil, but bottom layers may not be (see Listing
Background Document, 1995, p. 32). Even if a refinery analyzes the
waste, rather than simply using its ``knowledge'' as the generator
waste determination regulations allow, collecting representative
samples is challenging. Therefore, due to the oily, nonhomogeneous
nature of this particular waste, sampling and TCLP analysis may be
problematic.
Moreover, although nongroundwater risks from land treatment are not
significant, the carcinogenic PAH content of the waste is moderately
high (e.g., up to 26 ppm of BaP; see 60 FR at 57762). As noted earlier
in the discussion on groundwater issues (see Existing Groundwater
Contamination in Section V.B.6), while EPA could not quantify any PAH
risks from TCLP samples of this waste, the presence of carcinogenic
PAHs in the waste pose some potential for additional risk, especially
if transport is facilitated by existing contamination. While EPA is not
using the presence of carcinogenic PAHs as the overriding factor in
listing this waste, the presence of carcinogenic PAHs is a contributing
factor EPA considered in listing crude oil storage tank sediment.
Specific Comments
Some commenters supported EPA's proposed decision not to list crude
oil storage tank sediment, noting that the Monte Carlo analysis
strengthens this decision and highlights the conservatism in EPA's risk
assessment for the high-end analysis. In response, EPA notes that the
high-end risk (4E-5), in conjunction with the other factors noted
above, merits listing of this waste. The revised Monte Carlo risk at
the 95th percentile also are of concern (1E-5), albeit somewhat lower
than the high-end analysis. (See Section V.B.6 for further discussion
on the Monte Carlo analysis). Therefore, after considering a
combination of factors, including significant groundwater risk (i.e.,
risks above 1E-5), and the levels of carcinogenic PAHs found in these
wastes, EPA believes that a listing is warranted.
Commenters opposing EPA's proposed decision not to list presented
extensive comments on the risk analysis. These issues are already
discussed in the portion of today's notice devoted to the Modeling
Approach and Risk Assessment. Numerous comments challenged EPA's
groundwater risk assessment, and one commenter provided alternative
groundwater modeling that incorporated a variety of changes and
purported to show higher risks for this waste than found by EPA. As
noted in Section V.B.6, the Agency modified its modeling to reflect
some changes, which resulted in somewhat higher groundwater risks for
this waste, and EPA has now decided to list the waste.
Comments supporting a listing also argued that the Agency had not
evaluated the risks posed by management practices such as landfill
daily cover, road spreading, and other uses constituting disposal. EPA
disagrees as described in Section V.B.2; these are practices that were
rarely practiced for this waste. In any event, the disposal practice
modeled provided sufficient risk for EPA to list the waste.
The comments also noted that the concentrations of key constituents
in crude oil tank sediment (e.g., benzene and BaP) exceed those
reported in other wastes EPA listed in 1990 (55 FR at 46365; November
2, 1990). As EPA noted in the earlier discussion on consistency with
past listings, a simple comparison of constituent levels can be
misleading, because the Agency must consider many factors in its
listing decision. Furthermore, EPA's risk assessment methodology has
evolved since 1990. However, as noted above, EPA agrees that
limitations in detection limits for the PAHs in the TCLP make it
difficult for EPA to rule out potential groundwater risks completely.
In any case, EPA notes that it has decided to list crude oil tank
sediment as hazardous, primarily because of the risks from benzene,
thus these comments are not critical to the final decision.
One commenter stated that because of its variability, crude oil
tank sediment is precisely the type of waste stream that is best
regulated only if it exhibits hazardous characteristics. As noted
above, however, EPA is not relying on the TC to control risks, because
the results of the risk assessment show that this residual poses
sufficient risk to warrant listing as hazardous even with the TC
controls in place. Furthermore, the variability in this waste appears
to exist even within wastes removed from the same tank. EPA's sampling
visits indicate that this waste may form in layers in the tank, such
that it is not homogeneous when removed and processed. During tank
clean out, some of the oily sediment initially removed from the tank is
often deoiled (e.g., via centrifuging), but other more viscous layers
may not be (see Listing Background Document, October 1995).
[[Page 42152]]
Thus, even if a facility attempts to perform the TCLP test in good
faith, sampling such a material is a difficult challenge and could lead
to inaccurate results.
Finally, consistent with the proposal, it is EPA's intent that the
listing for crude oil storage tank sediment from refinery operations be
limited in scope to wastes generated from tanks that are either on the
refinery site, or at tank storage areas owned or under contract to the
refinery. Thus, the listing does not apply to storage tanks upstream at
exploration and production sites, or associated with pipelines or other
crude oil transportation conveyances. EPA's meaning with respect to the
term ``affiliated'' was to extend the scope of the listing to all tanks
containing crude oil that are owned by the refinery and used in
refinery operations. EPA has not collected data necessary to
characterize non-refinery sediments. Furthermore, many of these non-
refinery materials are governed by special statutory provisions (i.e.,
the ``Bevill'' provisions), and are currently exempt from regulation as
hazardous waste (See 60 FR at 57764.)
2. Clarified Slurry Oil Sediment
Summary
EPA is listing as hazardous CSO storage tank sediment and/or in-
line filter/separation solids from the filtration of CSO from petroleum
refinery operations. This waste stream meets the criteria set out at 40
CFR 261.11(a)(3) for listing a waste as hazardous, because it may pose
a substantial or potential hazard to human health or the environment.
The Agency identified substantial risks to residents and home gardeners
near on-site and off-site LTUs through direct ingestion of contaminated
soil released from these units. The contaminants of concern, PAHs, also
tend to accumulate in food sources such that this waste causes even
higher risks to nearby subsistence farmers and fishers. EPA is not
promulgating any of the proposed options for conditional listing,
because revised risk analysis for releases from off-site landfills
showed some risks of concern to consumers of groundwater (see Table IV-
2).
Discussion
The Agency proposed to list sediment from CSO storage tanks
(including solids from in-line filtration or separation of CSO) as
hazardous, due to high-end cancer risks of up to 9E-5 and 8E-5 arising
from receptors exposed to contaminated soil released from on-site and
off-site LTUs respectively. High-end risks associated with the landfill
disposal of this waste stream were below the 1E-6 level, and EPA
proposed various options for a conditional listing that would allow
nonhazardous landfill disposal, but prevent the practice of land
treatment. (See 60 FR at 57776).
In response to comments on the proposal, EPA modified the landfill
and land treatment risk assessments and published revised risks in a
NODA (see 62 FR at 16748). The overall risk pattern did not change
significantly for land treatment. Specifically, for the on-site land
treatment, the revised high-end risks increased slightly (up to 2E-4),
and for off-site land treatment the revised risks decreased slightly
(risks up to 3E-5)(see 62 FR at 16753). The revised high-end
groundwater risks due to benzene from off-site landfill disposal
increased from <1E-6 to 3E-6, and the Monte Carlo risks ranged from 1E-
6 to 3E-6 for the 95th and 99th percentiles.
In response to comments on the NODA, the Agency further revised the
input data for the groundwater pathway analysis as noted elsewhere in
this notice. As shown in Table IV-2, this final groundwater pathway
analysis showed slightly higher high-end risks (4E-6) and Monte Carlo
risks (2E-6 and 4E-6 at the 95th and 99th percentiles) for off-site
landfills. Based on the substantial risks arising from PAHs in land
treatment of this waste, EPA has determined to list this waste as
hazardous. At the time of proposal, EPA believed disposal of this waste
in nonhazardous landfills did not appear to pose significant risks, and
so raised the possibility of a conditional listing that would allow
this practice to continue. The Agency has now decided not to include a
conditional listing for this waste, primarily because landfilling of
CSO residuals appear also to pose some groundwater risk as a result of
the revised risk analysis (4E-6). Therefore, the Agency has decided not
to proceed with this new concept with this waste. Furthermore, EPA is
reluctant to encourage the landfilling of wastes with very high
carcinogenic PAH content (e.g., up to 230 ppm of BaP), which, as noted
above for crude oil storage sediment, may present risks if mobilized in
groundwater under certain conditions.
Specific Comments
Commenters responding to issues related to risk assessment of CSO
tank sediment argued that results were insufficient for a listing
determination because EPA found that 80 percent of the CSO tank
sediment does not pose a risk to human health and the environment, and
the remaining 20 percent of CSO tank sediment, disposed of in off-site
LTUs, was determined to pose risk in the discretionary range only after
imposing conservative assumptions.
After revising its risk assessments and considering all comments,
EPA disagrees with the commenter. Three subcategories of CSO sediment
can be identified. The first consists of the residuals land treated,
which were found to pose risk of concern via the risk assessment as
described in the proposed rule and the NODA. This volume accounts for
22 percent of the volume generated in 1992. The second consists of the
residuals landfilled, which were not thought to pose risk of concern
via the risk assessment as described in the proposed rule, and which
account for 50 percent of the volume generated in 1992. The third
consists of the balance of the residuals subjected to management
practices in 1992, which were not modeled because either the practices
were exempt (e.g., recycling), the residuals were already hazardous, or
the management practices for very small volumes of the residuals were
rarely practiced and/or adequately modeled by land treatment or
landfilling (e.g., on-site road material).
EPA reassessed the first two subcategories of CSO sediment
(management in LTUs and landfills), after modifying a number of
parameters and modeling considerations in response to public comment.
CSO sediment, when land treated, continues to exhibit risk levels (up
to 2E-4) supporting a listing determination, as described in the
discussion above. Furthermore, the revised assessment showed that
landfilled sediments also present some risks. Therefore, EPA has
decided not to proceed with a conditional listing that would allow
disposal in Subtitle D landfills, but rather is promulgating a full
unconditional listing for this waste.
As noted elsewhere in today's notice (Section V.B), EPA does not
agree with other comments that argued EPA should have assessed risks
from other management practices, such as use of CSO sediment as on-site
road material. In any case, EPA is listing this waste as hazardous,
thereby preventing such practices in the future.
Some commenters argued that the waste constituent characterization
related to analysis of the waste itself (not the TCLP extract) is
uncertain and overestimates risks. Specifically, they argued that some
PAHs were detected in only one sample at concentrations below the
quantification limit (i.e., ``J'' values), and that where this
concentration leads to an unacceptable risk estimate, CSO sediments for
the
[[Page 42153]]
entire industry could be listed based on a single estimated
concentration in one sample.
EPA does not agree that any uncertainty in the analysis resulted in
an overestimation of risk. First, EPA notes that even constituents
assigned a ``J'' value were reliably detected in the waste, although
the precise level has increasing uncertainty as the measurement
approaches the detection limit. More importantly, contrary to the
commenter's assertion, the CSO listing determination did not hinge on a
single estimated value, but rather considered all of the constituents
that showed risk. Several highly toxic PAHs detected in CSO tank
sediment (BaP, benz(a)anthracene, dibenz(a,h)anthracene, 7,12-DBMA)
were measured at levels above the quantification limits, and these
constituents in the waste presented substantial risks (i.e., > 1E-5)
without any consideration of ``J'' values.
Commenters argued that EPA did not follow its own guidance in
applying listing factors to CSO sediment, and that a description as to
how each of the listing factors weighs for or against listing should be
provided.
In response, EPA first notes that all the factors in 40 CFR
261.11(a)(3) are considered in this listing decision. The commenter has
not specifically identified any Sec. 261.11(a)(3) factors that were not
considered. Furthermore, EPA disagrees with the commenter and notes
that its revised risk assessment fully supports the listing
determination for CSO sediment and is in accordance with applicable
guidance. The guidance the commenter cites is contained in the December
22, 1994 proposed rule for the dye and pigment listings, in which EPA
discussed the use of risk levels in making listing decisions (59 FR at
66075-66077). EPA's decision to list this waste is consistent with the
guidance, i.e., the risks associated with this residual are well above
the 1E-5 listing benchmark.
EPA received comments that the Agency overstated the potential
risks from CSO sediment that is land treated, and that there are no
documented damage cases involving migration of PAH contaminated soils
from land treatment of CSO sediments.
In response, EPA points out that it attempted to identify damage
cases wherever possible to support its listing determinations (See
Assessment of Risks from the Management of Petroleum Refining Wastes:
Background Document, October 1995, in the docket). While EPA has
identified damage cases resulting from releases at petroleum
refineries, it was not possible to tie the releases directly to CSO
sediments (or other wastes under review in this rule) in LTUs due to
(1) the management of multiple residuals in LTUs, (2) the infrequent
generation of CSO sediments, and (3) the lack of a marker contaminant
unique to CSO sediments that could be linked to documented releases.
The lack of empirical evidence is not surprising, but does not prove
that releases are not possible or even unlikely. For this reason, EPA
did not rely heavily on damage cases that directly linked releases to
the specific residuals of concern. Instead EPA's weight of evidence
considerations emphasized its data collection efforts (i.e., the 3007
Questionnaire and field study) that provided EPA with the raw material
to evaluate a wide variety of measures of risk (e.g., modeling of
numerous pathways, groundwater modeling, hazardous waste
characteristics). By using information beyond proven damage cases, EPA
hopes to prevent releases that lead to environmental damage.
Several commenters requested that EPA clarify the definition of the
K170 listing for CSO waste. Their questions relate to whether the
listing: (1) applies just to CSO separately stored/managed or also to
all mixtures of CSO and other fuels, (2) includes fluidized catalytic
cracker (FCC) clean out/turnaround sediments, (3) includes sediments
from ``affiliated'' tank farms, and (4) includes spills of CSO.
Concerning mixtures of CSO and other fuels, EPA points out that any
sediments derived from CSO or CSO mixtures are considered K170 because
of the contribution of the CSO sediment to the ultimate residual. All
tanks that hold CSO have the potential to generate CSO sediment, and
this sediment may mix with sediment generated by other materials stored
in the tanks. Thus, the resulting sediment mixture would be classified
as hazardous waste K170 under the ``mixture'' rule (see 40 CFR
261.3(a)). The Agency anticipates that refiners will use the 6-month
period between the final rule date and the effective date to remove
``marginal'' storage tanks from service for sediment clean out and
subsequently use dedicated tank service for CSO storage to minimize the
number of tanks generating the listed hazardous waste.
Concerning clean out/turnaround sludges, throughout the EPA's
industry study, the Agency intended to incorporate clean out/turnaround
sludges from in-line particulate removal units within the scope of the
CSO sediment definition (see the 1995 Listing Background Document at
page 43). One primary component of these sediments and storage tank
sediments is FCC catalyst fines. Samples were collected from three
storage tanks and one in-line filter. No samples of turnaround
sediments were available during the Agency's field investigation;
however, several refineries described the removal of sediments from
other in-line separation units such as hydroclones during turnarounds.
EPA believes that sediments removed from the hydroclone during
turnarounds would be comparable to sludges removed from in-line filters
which serve the same purpose, because both are designed to perform the
same function, i.e., to remove solids from lines leading to CSO tanks.
No information was submitted by the commenters to demonstrate that
clean out/turnaround sediments from such in-line separation devices
differ from storage tank sediments.
The Agency therefore continues to use the broader definition of CSO
sediments, which includes sediments collected in filters and other
separation devices in lines that move the CSO from the FCC unit to
storage tanks. EPA does not, however, expect that all residuals
generated during FCC turnaround would be classified as K170, but rather
only those associated with in-line particulate removal equipment (e.g.,
hydroclones, in-line filters). This would not include sediments and
tars that may accumulate within the distillation columns.
EPA's meaning with respect to the term ``affiliated'' was to extend
the scope of the listing to all tanks containing CSO that are owned by
the refinery that produced the CSO. (See 60 FR at 57766). This CSO has
not yet been sold or transferred to another entity or corporation, and
remains the property of the refinery from which it originated. All
sediments settling from the CSO prior to sale are subject to the
hazardous waste listing. Similarly, once the CSO has been sold or
transferred in commerce, it is no longer under control of the producing
refinery. The listing determinations in today's rule are for wastes
generated from refinery operations, thus EPA has not examined for this
rule whether other sediments might be generated, and if generated,
under what conditions, after the CSO has been sold or transferred.
Concerning spills of CSO product, EPA does not intend to regulate
as hazardous the CSO itself, only the sediments that are removed from
this hydrocarbon product such as those generated in in-line separators
and those sediments that gravitate to the bottom of storage tanks. CSO
that is accidentally spilled on the ground may in fact
[[Page 42154]]
contain particulates that would have settled out as tank sediment.
However, the Agency did not address such spills in the proposed rule
and, in response to this comment, is clarifying that it does not
currently intend to regulate CSO spills as K170. Spills of K170 waste,
of course, would be regulated.
One commenter noted that EPA should consider an exemption from
designation as hazardous for CSO sludges that are de-oiled, and claimed
that de-oiled solids may be managed similarly to FCC catalyst and fines
units because they are very similar in composition (i.e., the wastes
would be landfilled and should not present a risk). The commenter
argued that providing a conditional exemption for de-oiled sludges,
perhaps with separate Land Disposal Restrictions (LDR) treatment
standards, would be environmentally sound, and would tailor treatment
to the nature of the waste stream.
EPA did consider whether the data available allow the Agency to
distinguish between CSO sediment (as well as crude oil storage tank
sediment) before and after de-oiling, especially for use in risk
assessment. However, the Agency concluded that distinguishing between
the two forms of CSO sediment was inappropriate based on the data
available (see Listing Background Document, 1995, pages 46 and 29).
Therefore, EPA disagrees with the commenter's suggestion to only list
``non-deoiled'' sediment because: (1) Available data do not provide a
sufficient comparison differentiation of risks between oily and de-
oiled CSO tank sludges, (2) the deoiling process may not remove the
PAHs of concern, and (3) crafting a definition of de-oiled sludges
would be difficult and may cause enforcement problems. Furthermore, as
shown by the high PAH content in CSO sediment, the solids appear to be
more than just spent FCC catalyst. EPA believes the exclusion for
recycled oil-bearing residuals that EPA is promulgating in today's rule
is a more effective approach to encouraging the recycling of the
material.
3. Catalyst From Hydrotreating and Hydrorefining
Summary
EPA is listing as hazardous spent hydrotreating and hydrorefining
catalysts from refining operations. This waste stream meets the
criteria set out at 40 CFR 261.11(a)(3) for listing a waste as
hazardous, because it may pose a substantial or potential hazard to
human health or the environment. The Agency identified substantial
risks to consumers of groundwater associated with releases from on-site
and off-site Subtitle D landfilling due to benzene and arsenic, which
EPA has decided will not be adequately regulated under the TC. The
revised groundwater risk assessment results are summarized in Table IV-
2. In addition, these materials also present a hazard because of their
pyrophoric and self-heating properties.
Discussion
The Agency proposed to list spent hydrotreating and hydrorefining
catalysts from refining operations due to high-end cancer risks of up
to 1E-5 and 6E-5 respectively arising from releases of benzene and
arsenic to groundwater from landfill disposal. (See 60 FR at 57766-
57768). In addition, as the Agency discussed in the proposed notice,
these materials also present a hazard because of their potential to
spontaneously ignite when removed from the processing unit and exposed
to air.
The revised groundwater risks in the NODA increased substantially
for these scenarios when compared to the proposed rule. The high-end
risks for hydrotreating catalyst were up to 7E-5 for off-site landfills
and up to 8E-5 for on-site landfills. For hydrorefining catalyst, the
high-end risks were up to 7E-4 for off-site landfills and 4E-4 for on-
site landfills. The TC-capping assessment in the NODA resulted in some
decrease in risks from benzene compared to the proposal, while the
arsenic risks showed little or no decrease. Thus the maximum high-end
risks were not materially affected. In addition, EPA provided a Monte
Carlo analysis that yielded somewhat lower groundwater risks; however,
as noted in an earlier section, EPA subsequently revised the Monte
Carlo analysis.
As a result of the revised risk analysis completed in response to
comments on the NODA, the off-site landfill groundwater risks increased
further. As shown in Table IV-2, the revised off-site risks for
hydrotreating catalyst are 1E-4 for benzene and 8E-5 for arsenic; the
TC-capped results for this waste showed lower risk for benzene (3E-5),
but arsenic was unchanged. Similarly, the revised off-site risks for
hydrorefining catalyst are 7E-5 for benzene and 6E-4 for arsenic, and
the TC-capped analyses for these wastes lowered the benzene risks (3E-
5) but had no impact on arsenic risk. The revised Monte Carlo risks for
hydrotreating catalyst (benzene 3E-5, arsenic 2E-5 at the 95th
percentile) and hydrorefining catalyst (benzene 2E-5, arsenic 4E-4 at
the 95th percentile) were somewhat lower, but still well above the
listing benchmark of 1E-5. As in the NODA analysis, the high-end and
Monte Carlo risks for arsenic were not lowered by the TC-capped
analysis. The TC-capped benzene risks for both catalysts were somewhat
lower in the high-end (both at 3E-5) and Monte Carlo analyses (9E-6 and
8E-6 for the hydrotreating and hydrorefining risks respectively).
EPA believes that the overall results are strongly supportive of
listing both spent catalysts. Even in the TC-capping results, both
catalysts present risks in off-site landfills that exceed 1E-5.
Specifically, for both hydrotreating and hydrorefining catalysts, the
TC-capped arsenic risks exceed 1E-5 for the Monte Carlo and high-end
evaluations, and the benzene risks exceed this benchmark in the high-
end evaluation and approaches this level in the Monte Carlo analyses.
As shown by the TC-capped modeling analysis, the risk levels may remain
at levels of concern, even assuming wastes above the TC level are not
disposed of in nonhazardous landfills.
In addition to the groundwater risks posed by these materials, the
pyrophoric and self-heating nature of these catalysts also support
EPA's conclusion that these materials present a substantial hazard.
During several site visits to catalyst reclaimers, EPA observed smoking
catalyst storage areas used to stage the catalysts immediately prior to
insertion into the reclamation process. One facility told EPA during
the site visit that fires occur every few months. These areas were
carefully monitored and controlled, but clearly the materials exhibited
pyrophoric properties. In addition, the refineries generating these
residuals described the significant risks during reactor turnaround
associated with the potential pyrophoric nature of these catalysts.
Therefore, EPA believes that it has solid basis for using the potential
self-igniting characteristic of these catalysts to support its decision
to list these residuals.
EPA wishes to clarify the scope of these listings, however. In the
proposal, the Agency indicated that the listings would not include
ceramic support media that are separated from the spent hydrotreating
or hydrorefining catalyst prior to catalyst disposal or recycling,
because these support media are inert, separate from the catalyst, and
commonly reused or sent for cleaning prior to reuse. (See 60 FR at
57780). EPA continues to believe this is appropriate. Some commenters
requested that EPA modify the regulatory language to refer to ``inert
support media,'' rather than the proposed ``ceramic support media,''
because other types of inert materials are used, such as stainless
steel. EPA agrees that the commenter's language
[[Page 42155]]
better reflects the Agency's intentions, and is modifying the exemption
language in 40 CFR 262.3(c)(2)(ii)(E) and the listing descriptions for
K171 and K171 to reflect this change.
In the proposed rule EPA also noted that the terms
``hydrotreating'' and ``hydrorefining'' are somewhat loosely used
within the industry. Several commenters requested a more concise
definition of the terms to clarify the definitions of hydrotreating,
hydrorefining, and hydrocracking processes. EPA provides further
discussion of the definitions of these wastes in the following section
on residual-specific comments. EPA is modifying the final regulatory
language slightly to clarify this issue, as noted in Section IV.B.
Specific Comments
Definition of Hydrotreating and Hydrorefining Catalysts
EPA examined three types of hydroprocessing catalysts identified in
the EDF consent decree: hydrotreating catalyst (listing candidate),
hydrorefining catalyst (listing candidate), and hydrocracking catalyst
(study residual). Spent hydrotreating and hydrorefining catalysts have
been proposed for listing and will be promulgated as hazardous wastes
in today's rule; no action has been proposed to date for spent
hydrocracking catalyst. (However, the listing of the spent
hydrotreating and hydrorefining catalysts does not release the
generator from determining whether spent hydrocracking catalyst is a
hazardous waste due to the characteristics under 40 CFR 262.11). Public
comment was submitted regarding EPA's hydroprocessing catalyst
definitions.
All three processes are part of a continuum of catalytic
hydroprocessing units. Definitions for the three categories of
hydroprocessors are not universally established or accepted. In
general, the three processes may be viewed in the following order of
increasing degrees of severity of operating conditions and conversion
of larger hydrocarbons to smaller molecules (``cracking''), and/or
feeds: hydrotreating, hydrorefining, and hydrocracking. The types of
catalysts used can be similar in all three processes.
The proposed regulatory language did not attempt to define these
catalysts, or differentiate them from hydrocracking catalysts. The
proposal referred to definitions used in the Oil and Gas Journal (60 FR
at 57767, fn. 7), which indicates that hydrotreating includes processes
where essentially no reduction in the molecular size of the feed
occurs, that hydrorefining includes processes where 10 percent of the
feed or less is reduced in molecular size, and that hydrocracking
includes processes where 50 percent of the feed or more is reduced in
molecular size.
Commenters on the proposal noted that the preamble definitions did
not provide a complete continuum, resulting in an unclear area between
hydrorefining and hydrocracking. Specifically, since hydrorefining
covered conversion rates up to 10 percent and hydrocracking covered
conversion rates greater than 50 percent, as defined by the Oil and Gas
Journal, it was not apparent how EPA would classify processes with
conversion rates between 10 and 50 percent. Several solutions were
suggested by the commenters:
One refiner suggested that EPA establish a definition of
hydrocracking that assumes a conversion rate of 15 percent or
greater and the use of downstream fractionation.
A catalyst reclaimer suggested extensive regulatory language
describing the specific types of catalysts, catalysts support media,
and catalytic applications associated with the different
hydroprocessing categories.
Other refiners commented that EPA should clarify that any
process with conversion rates greater than 10 percent should be
classified as hydrocracking.
Each of the options is problematic. Reliance on specific conversion
rates may allow for slight changes in operating and accounting
practices to result in reclassification of units that would otherwise
be considered hydrorefiners. Similarly, use of fractionation could be
interpreted to include stripper columns commonly employed after
hydrotreating and hydrorefining. The catalyst reclaimer's suggested
language was an exhaustive attempt to distinguish the types of
processes EPA intends to be within the scope of the listings; however,
other commenters argued it was inappropriate to adopt the reclaimer's
suggestion because EPA did not have sufficient basis to expand the
definition in this way. At this time, the Agency is reluctant to adopt
this extensive list within the regulatory language without additional
review and perhaps further information collection.
Upon reviewing all of the relevant materials available in the
docket, the Agency believes that the simplest way to differentiate
between hydrocracking units and other hydroprocessing units is to rely
on the categorization used in the DOE's Petroleum Supply Annual.
Refineries are required to submit Form EIA-820 annually to DOE's Energy
Information Administration. This form includes the mandatory submission
of data on operating capacity for catalytic hydrocracking and catalytic
hydrotreating. Catalytic hydrocracking is defined in the Petroleum
Supply Annual as:
A refining process that uses hydrogen and catalysts with
relatively low temperature and high pressures for converting middle
boiling or residual material to high-octane gasoline, reformer
charge stock, jet fuel, and/or high grade fuel oil. The process uses
one or more catalysts, depending upon product output, and can handle
high sulfur feedstocks without prior desulfurization.
In addition, catalytic hydrotreating is defined in the Petroleum
Supply Annual as:
A refining process for treating petroleum fractions from
atmospheric or vacuum distillation units (e.g., naphthas, middle
distillates, reformer feeds, residual fuel oil, and heavy gas oil)
and other petroleum (e.g., cat cracked naphtha, coker naphtha, gas
oil, etc.) [i]n the presence of catalysts and substantial quantities
of hydrogen. Hydrotreating includes desulfurization, removal of
substances (e.g., nitrogen compounds) that deactivate catalysts,
conversion of olefins to paraffins to reduce gum formation in
gasoline, and other processes to upgrade the quality of the
fractions.
For the purposes of the K171 and K172 listing descriptions, catalytic
hydrorefining is defined as a refining process with more severe (higher
temperature and pressure) operating conditions than the catalytic
hydrotreating process defined above for treating the heavier molecular
weight petroleum fractions, residual fuel oil and heavy gas oil.
Based on the Petroleum Supply Annual definitions stated above, if a
refinery has been classifying its hydroprocessor as a catalytic
hydrocracker for the purposes of the DOE's Form EIA-820, spent catalyst
from this unit would not be covered by K171 or K172 (with the exception
of guard beds, as discussed further below). Conversely, if a refinery
has been classifying its hydroprocessor as a hydrotreater processing
feeds other than residual fuel oil or heavy gas oil, spent catalyst
from this unit would be classified as K171; spent catalyst from a
similar unit processing residual fuel oil or heavy gas oil would be
classified as K172. Refineries have been reporting capacity information
to DOE for many years and today's rulemaking should serve as a
reference for the classification of these units.
In addition to the issue of defining hydrocracking units that are
not subject to the K171/K172 listing, there is
[[Page 42156]]
disagreement among commenters from the petroleum industry and catalyst
reclaimers regarding the classification of guard beds. These units,
also known as desulfurization pretreaters, are used to extend the life
of the downstream catalytic bed (e.g., reformer, hydrocracker,
isomerization reactor) by removing sulfur, oxygen, nitrogen, and/or
heavy metals. Reclaimers argued to include such pretreatment of
hydrocracker feeds, sulfur guards, reformer pretreatment, and
isomerization pretreatment as part of the definition of hydrorefining
or hydrotreating. The petroleum refining industry disagreed, stating
that these pretreatment processes use more severe conditions (much
higher pressure, high ratio of hydrogen to hydrocarbon) to achieve
contaminant removal, and also provide a significant reduction in
feedstock molecular size, often greater than the 10 percent cutoff in
the EPA/Oil and Gas Journal hydrorefining definition. Thus, industry
contends such catalysts more appropriately belong in the hydrocracking
category.
EPA agrees that these pretreatment units, or ``guard units,''
should be covered under the listing descriptions in today's rule.
In reviewing the 3007 Questionnaire responses, EPA found that some
refineries reported the catalysts from their guard beds under the
category of the downstream unit. For example, nickel/molybdenum
catalyst from a reformer pretreatment unit was sometimes reported as
spent reforming catalyst, however, true reforming catalysts are based
on precious metals such as platinum and palladium. EPA believes that
these units were not reported as hydrotreaters because they often
reside within the unit boundaries of the downstream units, are closely
integrated with the downstream units, and such reporting simplified the
refinery's response to the extensive 3007 Questionnaire. However,
because this type of guard bed does not result in catalytic reforming
(and similarly isomerization), these units were re-coded as
hydrotreaters in the Agency's database. EPA has modified the regulatory
language to clarify that the spent catalyst from all such pretreatment
units should be classified as K171 or K172.
Risk Assessment and Basis for Listing
Some commenters stated that EPA's groundwater analysis understated
the risks for these wastes. These comments reflected many of the issues
already discussed in the portion of today's notice devoted to the
Modeling Approach and Risk Assessment, but the Agency notes a few
issues specific to these wastes. Despite the commenters' arguments, EPA
remains convinced that it is appropriate to use the TCLP to
characterize the leaching potential of these residuals, as noted in
Section V.B.1. The Agency's analysis of total oil and grease content of
the catalysts showed very low oil and grease content (less than 0.2
percent) for the six samples for which EPA was able to conduct total
oil and grease analysis, thus these are not the ``oily'' wastes that
the commenter believes represent a problem for the TCLP. As the
commenters noted, EPA did not consider codisposal for these wastes.
However EPA believes it would be inappropriate to assess the impact of
codisposal of the catalyst residuals with other refinery wastes because
EPA is listing these wastes, and thus they must be disposed of in
Subtitle C units in the future.
Several commenters argued that EPA's analysis overestimated risks
in the Agency's assessment of spent catalysts from hydrotreating and
hydrorefining for various reasons. These commenters argued that EPA
data shows that 81 percent of these catalysts are already recycled or
reclaimed, but EPA assumed in its risk analysis that all this material
will go into landfills.
EPA disagrees with this comment. The Agency chose landfill disposal
as the mismanagement scenario for the groundwater risk analysis for
these wastes, because economic considerations and other information in
the record show that the recycled material could plausibly go to
landfills.
To calculate waste volumes to use as input to the modeling, EPA
evaluated the data in two ways: (1) EPA arrayed the volumes disposed in
on-site and off-site Subtitle D landfills in 1992 and determined the
50th and 90th percentile quantities (Tables 3.3.4 and 3.3.11 of the
1995 Listing Background Document), and (2) EPA arrayed the volumes for
all volumes generated by any facility regardless of the actual
management method (except for excluding wastes sent to Subtitle C), and
determined the 50th and 90th percentile quantities for these wastes.
EPA has used the second set of statistics in its risk assessment. Use
of these data reflects the real potential that shifts might occur in
management practices away from recycling and toward less expensive
landfilling if the wastes are not listed (see a discussion of this
issue in the Listing Background Document, 1995, pp. 78-79). Support for
this assumption is found in industry comment that refineries may send
spent catalysts to either recycling or landfill disposal, depending on
the associated costs. During site visits to both refineries and
catalyst recyclers, EPA learned that factors affecting spent catalyst
management include the price of metals, and consequently the value of
spent catalyst, and corporate policies toward recycling versus
landfilling. For example, one report from a visit to a refinery
(document # 95-PRLP-S0041) states: ``the spent catalyst is sent off-
site for metals reclamation or to a special waste landfill, depending
on market conditions.'' Another report from a site visit to a reclaimer
(95-PRLP-S0057) states that the company's fee structure is driven by
metals prices, and their costs and/or credits are dependent on the
current metals market. The reclaimer noted that more spent catalyst is
reclaimed when metal prices are high than when prices are low. EPA
therefore believes that management patterns of these particular
residuals could change in the future.
EPA only applied this assumption to three wastes (K171, K172, and
spent catalyst from sulfur unit tail gas treating units), because these
are all similar spent catalysts that are recycled at the same
facilities. EPA did not project changes in waste management practices
for other residuals, because the Agency has no specific information
that such changes are plausible or that special trends in management
practices exist. As noted in Section V.B.2, for the remaining
residuals, EPA considered that 1992 provided a reasonable picture of
the petroleum refining industry's practices.
Moreover, comparison of the two data sets shows the commenters'
concern that the approach used overestimates risks is unfounded. The
high-end (90th percentile) annual volumes calculated for both
approaches are nearly identical for hydrotreating catalyst, 70 metric
tons (MT) for the first approach versus 77 MT for the second. For
hydrorefining catalyst, use of volumes that are recycled actually
reduced the high-end volume somewhat, from 2,250 to 500 MT. (Note that
the decrease in the 90th percentile in this case is because the
addition of the recycled volumes creates a larger data set, and the
90th percentile point in the set is lowered for that in the smaller
data set for volumes sent to landfills). Thus, EPA's approach does not
overestimate risks.
TC-Capped Modeling
One commenter argued that EPA should not list hydrotreating
catalyst because, based on the TC-capped modeling analyses EPA
performed for the NODA, the risks for spent
[[Page 42157]]
hydrotreating catalyst disposal in landfills range from 2E-5 to 4E-6
from exposure to benzene (See 62 FR at 16752), and that these risk
levels are within EPA's discretionary range for not listing. One
commenter stated that EPA appropriately reported the risks from arsenic
as not applicable because spent catalysts containing arsenic at levels
sufficient to pose such risks are already covered by the TC Rule and
regulated under RCRA. The commenter also argued that the risks found in
the Monte Carlo analysis for hydrotreating catalyst were only 4E-6 at
the 95th percentile, and, thus, support a no-list decision.
EPA disagrees with the commenters. First, the commenters are
mistaken in suggesting that the arsenic risks are not applicable for
the TC-capped analysis. On the contrary, the risks do not change under
this assumption because none of the samples exceeded the TC level for
arsenic. As such, under the TC-capped analysis the arsenic risks would
remain the same as the uncapped analysis. As noted in the Discussion
section above, EPA continues to believe that the risks from the high-
end analysis fully support listing this waste, and the somewhat higher
revised groundwater risks further support EPA's decision. Even for the
TC-capped results, the revised arsenic high-end risks (8E-5) and Monte
Carlo results (2E-5 at the 95th percentile), as well as the high-end
risk for benzene (3E-5) clearly exceed the listing benchmark of 1E-5.
Commenters also argued that for hydrorefining wastes, TC-capped
groundwater risks from benzene range from 2E-5 to 6E-6 (See 62 FR at
16752), and these risk levels are within EPA's discretionary range for
listing (See 59 FR at 66073). While the comments conceded that the TC-
capped risk for arsenic in this waste are in the range EPA could
consider for listing (4E-4 to 1E-4), the fact that the peak arsenic
concentrations may not reach the receptor well until 3400 to 8400 years
after release, indicates that this is not significant. The commenters
also noted that the risks from benzene and arsenic cannot be added
because the time for peak concentrations at the well is much shorter
for benzene (13-50 years). The commenters argued that EPA should base
its decision on the lower Monte Carlo results (TC-capped risk of 6 x
10-6 at the 95th percentile for benzene).
EPA disagrees with the commenters. As noted in the Discussion
section above, EPA continues to believe that the risk analyses fully
support listing this waste, and the somewhat higher revised groundwater
risks further support EPA's decision. Even for the TC-capped results,
the revised Monte Carlo and high-end risks for arsenic (4E-4 at the
95th percentile and 6E-4), and the high-end risk for benzene (3E-5)
clearly exceed the listing benchmark of 1E-5. Contrary to what the
commenter implied, EPA did not add the benzene and arsenic risks,
because of the large differences in travel time. Further, EPA did not
discard the arsenic risk results merely because the modeling suggested
the constituent may not reach the receptor well in the near future. The
timeframe for travel may be uncertain, but the results suggest arsenic
will be a serious problem when it reaches the well.
EPA received comments stating that spent catalyst residuals should
not be listed based on the characteristic of ignitability, because the
spent catalysts do not demonstrate the property of self-heating, nor do
they fail the ignitability test.
As noted in the discussion above, persistent smoldering fires that
may propagate to other codisposed materials have been reported for
these residuals. Thus, listing of these wastes is further supported by
actual environmental and health damages. Actual damages constitute one
of the factors to be considered in listing wastes as hazardous under 40
CFR 261.11(a)(3)(ix). As noted previously, it is rare to have actual
damage cases to be attributable specifically to the wastes being
listed. The fact that EPA has knowledge of actual damage cases for
these wastes gives special support to their listing determination.
Furthermore, under the mismanagement criterion of 40 CFR
261.11(a)(3)(vii), it is appropriate to consider the physical
properties of these wastes that may result in hazards if there is
improper management through co-management with combustibles. Therefore,
EPA considers the self-heating physical property of these spent
catalysts to be very important in its decision to list these wastes.
With regard to commenter opinion that a listing is not warranted to
protect against fires resulting from spent catalyst being landfilled,
EPA observed and was told by catalyst reclamation and refinery facility
operators that these wastes exhibit pyrophoric properties and do result
in fires. Even where catalysts are coated with heavy oils to reduce
pyrophoric properties, this effect is not permanent as the oil coating
degrades, particularly if the material is disturbed at a later date and
exposed to the air, as could easily happen at landfills. EPA,
therefore, has a solid basis for using the potential self-igniting
characteristic of these catalysts to support its decision to list these
residuals
Impact of Listing on Recycling
EPA received a request for confirmation that solids generated from
scrubbers used to control emissions during the reclamation and
processing of spent hydrotreating and hydrorefining catalysts will not
be designated hazardous under the ``derived from'' definition as a
result of these proposed rules. The Agency points out that the
commenter is incorrect. In general, wastes generated from the treatment
of listed hazardous wastes are considered hazardous wastes, under 40
CFR 261.3(c)(2). This includes residuals generated by the recycling
activities described by the catalyst reclaimers who submitted comments
on this rule. Wastes generated in the manner described by the commenter
(e.g., ``derived from'' air pollution control wastes) would continue to
carry the hazardous waste code and be subject to land disposal
restrictions.
EPA received several comments regarding the impact of this listing
on recycling and management practices. Commenters noted that spent
catalyst can be generated such that it meets the LDR UTS for organics,
and that the metals of concern can be treated using metal fixation.
This would be relatively inexpensive compared to the increased cost of
recycling that will result from this listing, and might discourage
recycling.
EPA does not agree with the commenters' scenario for several
reasons. First, the treatment standards for the spent catalysts require
that any treatment reduce levels of organics to low levels. For
example, nonwastewater levels of benzene, toluene, and xylene must be
10 mg/kg or lower, and levels of naphthalene and phenanthrene are set
at 5.6 mg/kg. Because the K171 and K172 wastes each frequently contain
reactive sulfides and as a result may exhibit self-heating pyrophoric
properties, the Agency also listed reactive sulfides as one of the
hazardous constituents of concern in these wastes and specifically
proposed to apply deactivation to these wastes. Thus, EPA does not
believe it is likely that generators can meet all applicable LDR
standards without appropriate treatment, such as treatment at a
recycling facility. EPA concedes that listing may increase costs for
recycling, however, EPA is not convinced that costs for other forms of
treatment and disposal would be appreciably less. In any case, EPA's
decision to list these materials is based on the risks they pose, and
how this listing may
[[Page 42158]]
ultimately affect competing treatment technologies is not a central
issue in the Agency's decision.
Other commenters pointed out that current recycling of these
catalysts has been due, in part, to the economics of reclamation
compared to disposal. A listing would, however, disproportionately
increase costs of and liability concerns about recycling. Some
commenters noted that by listing these wastes, transportation costs
will become a significant factor as materials will need to be
transported as hazardous, regardless of their characteristics;
increased transportation costs would strongly favor local disposal at a
Subtitle C facility, and generators would be less likely to ship wastes
farther distances to recycling facilities. Another commenter suggested
that a listing will decrease recycling, and increase the demand for
virgin metals. Thus, the overall environmental benefits from the
listing determination are likely to be negative, because there will be
more disposed of catalyst, and more production of virgin metals.
EPA cannot know precisely what the ultimate costs will be for
refineries to recycle or dispose of spent catalysts. The Agency
believes the liability concerns described will continue to play a role
in both landfilling and recycling decisions upon promulgation of this
listing. The affected industry must first explore means to eliminate or
minimize the newly listed waste, and then to optimize recycling,
treatment, and management of remaining wastes. The basis of EPA's
listing decision, however, centers on the results of its risk
assessment, which demonstrates that these materials pose a potential
risk to human health and the environment, and warrant Subtitle C
control. The Agency also points out that, because of the listing, the
recycling/disposal cost differential may arguably be reduced or
reversed, because Best Demonstrated Available Technology (BDAT) and
Subtitle C disposal costs will greatly increase the costs of disposal
over the current practice of Subtitle D landfills. Thus, recycling is
likely to continue to be an effective management option for these
residuals.
Furthermore, based on EPA's discussions with the recycling industry
(see discussion of metal reclaiming for hydrotreating catalyst in
Listing Background Document, 1995, pages 76-79), many of the reclaimers
currently have RCRA storage permits to allow them to manage
characteristically hazardous catalyst, so it is not clear that the
costs for recycling should increase significantly due to listing. Even
if recycling costs may increase as a result of this rule, EPA continues
to believe that it is completely appropriate to bar these materials
from Subtitle D disposal because of the risk levels identified through
the Agency's risk assessment procedures. EPA has no evidence, nor did
commenters provide any, to support the supposition that the listing
would increase demand for virgin metals.
Many commenters requested that the Agency consider an exemption for
the regeneration/reclamation/recycling of spent catalyst. The catalysts
would be listed only if they are disposed of in a landfill (or,
alternatively, not recycled). Other commenters proposed a conditional
listing for catalyst residuals going to land disposal. The suggested
conditions include that the residual is sent to metals reclaiming,
catalyst regenerators, or other recycling or reuse (provided it is not
a ``use constituting disposal''), records are kept on recycling and
reuse, and that self-heating residuals are shipped in Department of
Transportation (DOT) bins. The commenters argue that such a listing
would encourage recycling rather than landfilling.
EPA believes that the catalyst wastes present several risks beyond
those necessarily associated with landfill disposal, including
pyrophoric properties and significant levels of benzene and arsenic
(all of which may pose risks via pathways other than groundwater
exposure, including risks from improper storage or other handling, and
risks from uncontrolled air emissions from thermal treatment). Thus,
this waste is not a good candidate for a conditional listing. Given the
hazardous nature of this waste, EPA believes it is entirely appropriate
for it to be transported and stored as hazardous waste before
recycling. (See 40 CFR 261.6 for regulations applicable to hazardous
wastes that are recycled). EPA points out that examples of problems at
sites recycling these wastes have been noted in the record (see
enforcement case described in the docket, document #PRA-S0037).
4. Catalyst From Sulfuric Acid Alkylation
Summary
The Agency is not listing as hazardous catalyst from sulfuric acid
alkylation, as proposed. EPA hereby incorporates, as a final decision,
the proposed preamble discussion for this waste stream at 60 FR 57768-
57769. The residual is managed almost entirely (> 99 percent) under an
existing exemption from the definition of solid waste (40 CFR
261.4(a)(7)). Also, this residual consistently exhibits the
characteristic of corrosivity and is subject to regulatory control if
not returned to the production of virgin sulfuric acid. No significant
comments against this decision not to list were received during the
public comment period. Therefore, EPA has no basis to change the
decision not to list.
5. Spent Caustic From Liquid Treating
Summary
EPA is issuing a final decision not to list spent caustic from
liquid treating as a hazardous waste. About 70 percent of the spent
caustic is managed in ways that are exempt from RCRA regulation,
because it is reused as an ingredient in producing other products. The
Agency has identified certain management practices used for spent
caustics for which the Agency is clarifying the application of the
definition of solid waste, and in one case proposes a modification to
the definition.
Almost all of the remainder is sent to regulated wastewater
treatment systems in such small volumes relative to other discharges,
that the diluted constituents of concern from the spent caustics are
not expected to present any significant risk. Furthermore, any solids
from the caustic that separate out prior to downstream biological
treatment are already regulated as hazardous wastes.
After analyzing other potential exposure pathways, EPA concluded
that with regard to any remaining risks, with the exception of air
exposure pathways from open tank storage, there were no potential risk
pathways that need to be modeled. EPA found that risks from air
releases from the open tank storage scenario presented insignificant
risk.
Moreover, this residual will frequently exhibit the characteristic
of corrosivity (i.e., pH will be above 12.5) and toxicity due to cresol
leachability (and sometimes ignitability) and is subject to all
applicable regulatory controls when any of the hazardous waste
characteristics are present.
Discussion
The Agency proposed not to list this waste as hazardous and has
found no reason to change this decision after consideration of public
comments and all other information available in the rulemaking record.
EPA's 3007 Questionnaire showed that 51 percent of the waste stream is
reused as an ingredient or substitute for virgin caustic and, is thus
eligible for exclusion from the definition of solid waste under 40 CFR
261.2(e). The exclusion provides that secondary materials that are used
or reused directly (i.e., without reclamation) are
[[Page 42159]]
not subject to regulation under RCRA and are therefore not subject to
any listing determination. In addition, the proposal noted that
characteristically hazardous spent materials that are reclaimed prior
to reuse would still be hazardous wastes subject to pertinent
management requirements. Therefore, as noted in the proposal and
confirmed in this final decision, there is no reason to cover this
portion of the waste stream in the listing.
In addition, 17 percent of the spent liquid treating caustics are
used as valuable commercial feedstocks in the manufacture of cresylic
or naphthenic acids. Accordingly, EPA in today's final rule, for
reasons stated in the preamble to the proposed rule at 60 FR 57769-
57770, is amending 40 CFR 261.4(a)(19) to clarify that spent caustics
used in this manner are not solid wastes and, therefore, should not be
subject to listing.
For the 29 percent of the wastes sent to wastewater treatment
systems, EPA's analysis in the proposed rule found that risks from this
practice are unlikely. As noted in the proposed rule, risks from such
treatment are unlikely to be of concern because: (1) Treatment is
already regulated under Federal water (NPDES) and air (benzene National
Emissions Standards for Hazardous Air Pollutants (NESHAP), Maximum Air
Control Technology (MACT) standards) programs; (2) sludges generated
from wastewater treatment are already regulated as hazardous waste
(i.e., K048, K051, F037, F038); (3) volumes of the discharged residuals
under evaluation are relatively small in comparison to the volumes
typically treated in wastewater systems; and (4) the wastewater
treatment systems are designed to treat refinery wastes effectively
(see discussion below).
The Agency concluded that there were no potential risk pathways
that needed to be modeled except air exposure pathways from open tank
storage. For open tank storage, the Agency's bounding risk assessment
estimates resulted in no significant risks (see 60 FR at 57770). In
addition, this waste consistently exhibits the characteristic of
corrosivity (and often toxicity due to cresols), and, therefore, could
not be otherwise discarded without being subject to regulation as a
hazardous waste.
Specific Comments
In comments on the proposed rule, one commenter argued EPA only
evaluated potential risks associated with tank storage, that EPA must
evaluate the groundwater impacts from surface impoundment management,
since that method of management is both an actual and plausible
mismanagement scenario. The commenter stated that several refineries
reported managing spent caustic in surface impoundments in 1992, and
that the high-end volume of 596 MT managed in surface impoundments
exceeds volumes EPA modeled for other waste practices. The commenter
also noted that controls on surface impoundment risks by Phase III and
Phase IV LDR rules cited by EPA in the proposal as being able to
effectively regulate these wastes were not finalized.
In response, EPA wishes to clarify a few points. First, in every
case described in the 1992 database, these surface impoundments were
part of the refineries' wastewater treatment systems. EPA has no data
indicating that undiluted caustics were managed in surface
impoundments. Therefore, to model this scenario appears unreasonable.
Second, EPA did, in fact, conduct a screening analysis of the impact
spent caustic would have on the wastewater treatment plant, as
described in the docket to the proposed rule, but found that the
dilution with other process wastewaters was so great that no impact was
observed (see page 152 of the Listing Background Document, 1995). In
further considering this scenario, EPA estimates that the 90th
percentile quantity of spent caustic discharged to wastewater treatment
in 1992 (approximately 4,000 MT) would be diluted by a factor of about
3000. Thus, EPA does not believe that additional risk assessment is
necessary. In addition, the constituents of concern (relatively low
levels of certain volatile organics and metals, see the 1995 Listing
Background Document for details) in these residuals are generally
indistinguishable from those found in other residuals (many already
listed as hazardous waste) typically discharged to wastewater
treatment, making it virtually impossible to attribute any subsequent
concentrations in sludges or environmental releases to the contribution
from spent caustics. The combination of dilution and the expected
toxicant removal and destruction that the wastewater treatment plants
are designed to accomplish should effectively treat the spent caustic.
In addition, the Agency continues to believe that significant
regulatory control of any spent caustic-derived treatment sludges
already exists. Sludges and other residuals from the initial oil/water/
solids separator are already regulated as K048 and K051. Sludges from
oil/water/solids removal surface impoundments are also regulated as
hazardous in the petroleum refining industry, through the F037/F038
listings. Clearly, risks associated with biological treatment sludges
and wastewaters downstream from these units are reduced as a result of
the prior removal and treatment, including biodegradation. Further
regulatory controls also exist for these sludges and wastewaters via
the TC. In addition, the benzene NESHAP (58 FR 3072, January 7, 1993)
and the planned air standards for volatile organics emissions (MACT
standards proposed in 61 FR 17358, April 19, 1996) provide regulatory
mechanisms for control of air emissions, and wastewater discharges are
covered by the NPDES program.
EPA does agree that it is no longer appropriate to rely on the
regulatory controls originally anticipated via the Phase III and IV
land disposal restrictions. The Land Disposal Program Flexibility Act
of 1996 caused the Agency to withdraw the LDR Phase III treatment
standards (see 61 FR 15660, April 8, 1996), and not to finalize the
proposed LDR Phase IV provisions (see 62 FR 25997, May 12, 1997).
However, as required under the Act, EPA is currently conducting a 5-
year study of surface impoundment usage, and if the study indicates
that risks from impoundments are significant, EPA will then consider
the need for further regulatory controls.
One commenter noted that EPA's sampling indicates that spent
caustic from liquid treating ``consistently exhibits'' a characteristic
(the corrosivity characteristic, and TC for cresols and benzene), thus
it should be listed as hazardous under EPA's listing criterion in 40
CFR 261.11(a)(1). The commenter argued that current regulatory control
depends upon whether the particular waste exhibits a characteristic (a
determination the generator can reach based solely upon his or her
``knowledge'' of the waste).
EPA agrees that this residual frequently and typically exhibits one
or more of the characteristics. However, because the majority of
caustic management practices are either exempt from regulatory control
or are adequately regulated under other regulations (e.g., the
characteristics), the Agency believes that listing as hazardous waste
is not necessary. In response to the commenter's concern regarding
knowledge that this residual exhibits a characteristic, EPA notes that
this material is commonly acknowledged as corrosive due to its highly
caustic nature (hence its name), and managed in a manner to minimize
corrosion problems during storage. Thus, the Agency believes that
generators of spent caustic are well
[[Page 42160]]
aware of the potential for this residual to exhibit hazardous waste
characteristics, and manage their spent caustic accordingly. Given the
existing regulatory controls and management practices for this waste,
EPA continues to believe that listing is not warranted.
Several commenters believed that the use of caustics in the
manufacture of cresylic acid and naphthenic acid has always been
excluded from the definition of solid waste under 40 CFR 261.2(e)(1)(I)
and that a promulgation of the proposed specific exclusion might
indicate that up until now, these caustics have not been excluded.
Thus, the commenters requested clarification.
In response, EPA notes that the Agency and several states have been
involved in a longstanding discussion with industry regarding the
regulatory status of these materials. The promulgation of this rule
presents EPA's final findings, and is intended to put an end to
discussions regarding possible ambiguities in the current rules. The
purpose is to settle this matter once and for all, and we are doing so
by providing a clear regulatory exclusion.
6. Off-Specification Product and Fines From Thermal Processes Summary
EPA is not listing as hazardous off-specification product and fines
from thermal processes. No risks of concern were identified for those
materials that actually are discarded. Most of the materials generated
from these thermal processes are coke product and are stored in piles
with other coke product before they are resold. These piles are not,
therefore, subject to RCRA jurisdiction or they are exempt from RCRA
regulations.
Discussion
The Agency proposed not to list these materials, which are
generated from various refinery coking operations. Of the 194,300 MT of
these materials generated, approximately 87 percent is collected and
combined with product inventory to be sold. However, more than 7,250
tons (3.7 percent) are landfilled in on-site or off-site Subtitle D
landfills. These discarded materials were the wastes on which the
Agency conducted its risk assessment.
EPA determined that other management practices, including fines
sent to wastewater treatment, would not serve as a basis for listing
and adopts the reasoning in the proposal for this determination as part
of its final decision. (See 60 FR at 57770-57771). In summary, fines
sent to wastewater treatment are insoluble and will be incorporated in
primary treatment sludges that are already listed as K-and F-wastes;
LTUs received very small waste volumes; and other management practices
do not actually isolate the materials from the coking process and,
thus, are not wastes.
Commenters questioned why EPA did not assess risks from coke fines
placed on piles of coke product, arguing that the waste does not become
a product simply because it is placed on the pile and combined with
another material. In the NODA, EPA provided further clarification on
the jurisdictional basis for not evaluating the majority of off-
specification product and fines that are managed as coke product. The
Agency explained that only particle size distinguishes coke fines from
other coke product. The majority of coke is removed from the coker by
hydraulic drilling and coke fines are merely the smaller pieces of coke
generated during this process.
In addition, EPA explained there is a jurisdictional distinction
between coke fines produced from non-hazardous materials and coke fines
produced from hazardous wastes (waste-derived fines).24
Fines generated from non-hazardous materials are simply coke product,
as would be expected because they are produced from the same coking
drum. In the case of waste-derived fines, so long as the fines are
legitimate coke product, they are exempt from RCRA regulation unless
the material exhibits a characteristic as provided in 40 CFR
261.6(a)(3)(v). (See also RCRA section 3004(q)(2)(A)). EPA had no
information that waste-derived coke fails any hazardous waste
characteristic. The Agency invited comment or data to the contrary but
received none.
---------------------------------------------------------------------------
\24\ See the discussion on oil-bearing hazardous secondary
materials inserted into the petroleum refining process, including
the coke, in today's preamble for modifications to the definition of
solid waste concerning these materials.
---------------------------------------------------------------------------
In any event, EPA determined that the use of hazardous waste in the
production of coke would result in little, if any, change to the
qualities and the properties of the coke and fines produced. These coke
fines would have essentially the same composition as fines generated
from non-hazardous feed materials. The waste-derived fines are combined
with other coke in a product pile for storage prior to sales and are
coke product. The NODA also provided additional analyses on the
similarity of coke fines to existing coke product, and the potential
impact of recycling hazardous waste to the coker.
EPA has no reason to change this jurisdictional determination or
the determination that management scenarios other than Subtitle D
landfilling could not serve as a basis for listing. Therefore, the
Agency adopts these determinations as part of the basis for issuing the
final decision not to list this waste stream as hazardous.
With respect to the Subtitle D landfilling scenarios EPA evaluated
for the off-specification product and coke fines that were discarded,
EPA notes that groundwater risk estimate of 1E-5, as well as the
revised high-end risks in the NODA of 5E-6 to 2E-5 were within the
Agency's initial risk level of concern.
However, EPA noted significant problems with the groundwater risk
assessments. First, this risk was based entirely on the detection of
one PAH, benzo(a)anthracene, in only one out of six leaching samples at
a level 8-fold below the analytical quantification limit. Thus, EPA had
low confidence in this value and the subsequent modeling based on this
number. Second, the water solubility of this chemical is also very low,
indicating that its aqueous concentration is likely to be very low.
Third, this chemical is tightly adsorbed to organic material in soils
and sediment, indicating that the constituent is relatively immobile in
groundwater.
The NODA analysis, therefore, led EPA to determine that it is
highly unlikely that this waste would present a significant risk in a
groundwater scenario. EPA finds no reason to change that determination
either based on NODA comments or any other information in the
rulemaking record. In addition, further assessments in the NODA showed
no significant risks from the relatively small volumes that were
disposed in LTUs.
EPA's decision not to list is further supported by additional
analysis after comments received on the NODA. In its reexamination of
the groundwater analysis EPA found that it had mistakenly used the
wrong carcinogenic risk factor for benzo(a)anthracene. As shown in
Table IV-2, when the revised groundwater analysis was performed with
the longer active life and municipal landfill areas, using the correct
health-based number caused the risks to drop 20-fold, such that even
the maximum high-end risk was 2E-6. See Additional Groundwater Pathway
Analyses, 1998, contained in the public docket for this rule for
details. Given the even lower groundwater risk calculated, still using
the suspect benzo(a)anthracene measurement, EPA finds even further
reason to believe that the listing of off-specification product and
fines is not warranted.
Specific Comments
One commenter claimed EPA data indicates that several respondents
store
[[Page 42161]]
off-specification products and fines in surface impoundments as an
``interim'' management method, and therefore the Agency should model
this management. In response, EPA finds only one respondent, not
several, that reported managing off-specification product and fines in
a ``surface impoundment'' in 1992. This ``surface impoundment'' acts as
a drilling water clarifier. All delayed coking units recycle their
drilling water, and to do so, any entrained fines in the drilling water
must be recovered. Typically, the concrete coke storage pad is sloped
so that drilling water drains to one end and proceeds through a series
of baffles that separate out the coke fines. This is the type of
``surface impoundment'' the refinery identified. Thus it is not a
typical surface impoundment, but rather an integral part of the
decoking process. These are lined (concrete) drilling water collection
and recycle systems, confined within the coke battery, and are unlikely
to pose significant risk.
Comments related to the aspects of the groundwater modeling are
discussed earlier in this notice (see Section V.B.6); however, EPA
makes several points for this specific wastes. Regarding the
commenters' criticism of EPA's use of TCLP results as input values to
the landfill groundwater modeling for this material because it is
``oily,'' the Agency points out that off-specification product and
fines are generally not oily. The Agency conducted total oil and grease
analyses on four samples and the average level of oil and grease
(measured as Total Oil and Grease, i.e., not truly ``free'' oil) was
two percent (three samples were below one percent). Furthermore, the
data from the 3007 Questionnaire show that the typical material has
relatively low oil content (90th percentile value was five percent).
Therefore, EPA believes that the use of the TCLP was valid.
With regard to commenter concern over free-phase flow of
contaminants from off-specification product and fines due to oil
content, it is particularly important to note that none of the six off-
specification product and fines from thermal processes samples
exhibited multi-phase behavior, and that the measured oil content was
low, as noted above.
The commenter went on to state that a risk assessment EPA conducted
for this waste as part of the 1995 proposal showed that risks
associated with air releases from uncovered landfills made up of coke
fines exceeded 1E-3 for home gardeners, subsistence farmers, and
subsistence fishers, and a high risk to subsistence fishers from
mercury exposure was also predicted. The commenter also noted that the
NODA risk modeling for disposal in LTUs was not a meaningful surrogate
for evaluating the risks posed by pile storage, because the annual
volumes modeled were small (high-end volumes of 21-34 MT).
The commenter is attempting to use a bounding analysis EPA
undertook for nongroundwater risks for coke fines disposed in landfills
as an indication that air releases from piles containing this material
would present similar risks. In response, EPA first notes that bounding
estimates are used as an initial screening estimate that overestimates
the exposure or dose for the purpose of screening out exposures of
little concern. The purpose of the bounding analysis is simply to
determine what pathways and scenarios require further evaluation and
does not represent an assessment of risks. The bounding analysis
included worst-case assumptions (no cover or dust suppression, highest
constituent levels, largest waste volumes and landfill area, worst
climate, etc). Furthermore, the levels near 1E-3 arose from indirect
pathways (ingestion of beef, dairy, fish, and plant products); the
direct pathway of soil ingestion, even in the bounding analysis, was on
the order of 1E-6. Most importantly, the biotransfer factors used in
the bounding analysis for beef, dairy, and plant indirect paths have
been determined to overestimate risks by at least two orders of
magnitude; likewise the apparent problem from mercury also was traced
to an error in units for the bioaccumulation factor used. Thus, EPA
believes that the bounding analysis was flawed and grossly
overestimated risks.
EPA notes that the subsequent high-end analyses for nongroundwater
risks from landfill disposal of off-spec product and fines did not show
significant risk. While the high-end analysis included the assumption
of daily cover for the landfill, and thus may not be the best surrogate
for air releases from piles, the scenario did consider windblown dust
from on-site roads and particulate release caused by traffic (i.e.,
dump trucks), loading, unloading, etc. The high-end analysis showed
risks no higher than 2x10-6 for any receptor (see U.S. EPA, Assessment
of Risks from the Management of Petroleum Refining Wastes Background
Document (F-95-PRLP-S0006), page 10-3). Therefore, some of the possible
release mechanisms that could occur in a waste pile scenario (e.g.,
unloading/loading, traffic) were addressed in the risk assessment
supporting the proposal and the pathway was not significant.
EPA also points out that some important characteristics of the coke
pile and details of management practices used by refineries would tend
to mitigate potential risks. The piles are not comprised simply of coke
fines, but are mixtures of much larger pieces of coke product that are
drilled from coker units; the larger chunks of coke would make up the
bulk of the pile. Furthermore, coke is drilled out of the coker
approximately once a day with hydraulic drills; thus, new wet coke/
fines from drilling are added to the coke pile, making air releases of
dry particulates less likely. EPA also has found that coke piles are
managed using various practices to control release of dust, including:
(a) Contained product storage areas (b) dust-suppression water spray
systems (c) covered conveyor systems and, (d) direct loading from coke-
drums into railcars (see NODA response to comment document for a
summary of these practices). In addition, EPA expects that particulate
releases from these areas would be controlled by Federal, State, or
local air regulations and permit programs.
Finally, the commenter also argued that, pursuant to the Consent
Decree in EDF v. Browner, EPA is required to issue a listing
determination for off-specification products and fines, and that
because piles present a substantial risk to human health and the
environment based upon the assessments conducted to date, the required
listing determination must include a decision as to whether off-spec
products and fines warrants listing pursuant to 40 CFR 261.33 as a
commercial chemical product. The commenter suggested that, if EPA
argues that the piles of coke fines are product, then the material that
blows off the piles and cannot be recovered is discarded commercial
chemical product and should become a listed U-waste under 40 CFR
261.33(f).
EPA disagrees with the commenter. The Agency has, in fact, made a
listing decision for the off-specification product and fines that are
known to be discarded by refineries, i.e., the volumes of wastes that
are disposed. EPA believes it has fulfilled the requirements of the
consent decree for production wastes from petroleum refining. While the
Agency is not constrained to making decisions required under the
consent decree, EPA is not making a listing decision on product use in
this rulemaking. Furthermore, at this time the Agency has no valid
assessment that indicates these wastes present a ``substantial risk''
when added to coke piles.
[[Page 42162]]
7. Catalyst and Fines From Catalytic Cracking
Summary
As proposed, EPA is not listing as hazardous Fluidized Catalytic
Cracking (FCC) catalyst and fines. Two subcategories of this waste were
evaluated due to their physical difference in particle size: spent
equilibrium catalyst and catalyst fines. The usual constituents of
concern found in other petroleum residuals (i.e., carcinogenic PAHs and
benzene) were not detected in spent FCC catalysts. More than 70 percent
of the equilibrium catalyst and 20 percent of the catalyst fines are
reused (in other FCC units) or recycled (primarily by cement plants).
For the reasons stated in the proposal, the Agency chose to model the
monofill and surface impoundment scenarios (see 60 FR at 57771) for FCC
catalyst and FCC fines. Bounding estimates (run under worst-case
assumptions using multiple high-end assumptions for critical
parameters) for the nongroundwater exposures from volatile and
particulate emissions from monofills showed no significant risk for
either FCC equilibrium catalyst or FCC fines. The Agency also found no
significant risk, for either subcategory, from the high-end analysis
for the groundwater pathway from the monofill or surface impoundment
scenarios. Furthermore, the revised risk analyses in the NODA in
response to comments showed no significant risks for this waste. The
few comments EPA received on this waste agreed with EPA's decision not
to list. Therefore, the Agency continues to believe that a no-list
decision is warranted and adopts that final decision incorporating the
reasoning in the preamble to the proposal.
8. HF Alkylation Sludge
Summary
The Agency is not listing as hazardous sludge from hydrofluoric
acid (HF) alkylation processes. As noted in the proposal and confirmed
by analysis of comments and all other relevant information in the
record, only marginal risk was identified for the groundwater ingestion
pathway in off-site landfilling due to benzene. Also, no significant
risks were found from land treatment of this material.
Discussion
In the proposal, EPA found a high-end groundwater risk for
landfills of 3E-6 due to benzene (see 60 FR at 57772). The Agency also
noted that benzene was found in only one out of five TCLP samples,
indicating that the risk attributed to this chemical would generally be
lower. EPA did not model other waste management practices because they
were already regulated under RCRA (e.g., combustion in a industrial
furnace), extremely rare (discharge to a surface impoundment that has
been closed), recycling practices (on-site recovery), and/or would
present no significant risk (discharge of small volumes to wastewater
treatment systems).
In the NODA, the Agency revised the groundwater risk analysis for
landfill disposal and found slightly higher high-end risks for
groundwater for off-site and on-site landfills (both 6E-6) due to
benzene. EPA also presented a groundwater Monte Carlo analysis in the
NODA that showed risks of 2E-7 for on-site, and 2E-6 for off-site
landfills. Revised nongroundwater risks from disposal in LTUs remained
insignificant (less than 1E-7; see 62 FR at 16753).
Further groundwater pathway analysis performed in response to
comments on the NODA showed a slight increase in the high-end risk to
1E-5 for off-site landfills. The revised Monte Carlo analysis yielded
no change in the risk (2E-6). (See Table IV-2, and Additional
Groundwater Pathway Analyses, 1998, contained in the public docket for
this rule).
EPA decided not to list this waste based on the relatively low
groundwater high-end risks of 1E-5 due solely to benzene, and the fact
that benzene is not frequently found in the TCLP analysis (one of five
samples). Furthermore, this waste typically does not have high oil or
PAH content; none of the carcinogenic PAHs were detected in the samples
collected by EPA. Therefore, the Agency is issuing a final decision not
to list this waste stream.
Specific Comments
The Agency received comments arguing that sludges from HF
alkylation are frequently generated and managed in surface impoundments
and were not evaluated by EPA because it is a ``rare'' management
practice. The commenter stated that there are an ample number of
surface impoundments at refineries that could be used in this manner,
there is no legal or other barrier to surface impoundment management of
HF alkylation sludge, and that this practice should be considered a
plausible management scenario. The commenter noted that the waste is
sometimes generated in ``pits,'' and this means management in an
impoundment is a reasonable assumption.
EPA disagrees with the comment that HF sludge is commonly generated
or managed in surface impoundments. From site visits, EPA found that HF
alkylation sludge is commonly generated in concrete lined pits or tanks
within the HF process unit boundary; these are not unlined surface
impoundments. The one case of actual management of this waste in a
surface impoundment in 1992 was reported to be discontinued that year
(see Listing Background Document, October, 1995). Therefore, EPA does
not believe management in surface impoundments is plausible.
One commenter criticized EPA's modeling of risks from LTUs, and
these are addressed elsewhere in today's notice (see Section V.B.7).
However, EPA would like to note that nongroundwater risks are unlikely
to be significant for this waste because HF alkylation sludge has none
of the carcinogenic PAHs that were of concern for other wastes. For
example, while CSO sediment samples had an average of 132 ppm of the
PAH benzo(a)pyrene, none was detected in any sample of HF alkylation
sludge.
One commenter argued that EPA should list this waste based on the
groundwater risks estimated by EPA, as well as the risk calculated by
the commenter using alternative groundwater modeling (2E-5). EPA
disagrees with the commenter, and continues to believe the risks do not
justify listing this waste. As noted in the discussion above, EPA's
revised high-end risk was 1E-5, and the revised Monte Carlo risk only
2E-6. EPA has decided not to list this waste after considering other
factors. Most importantly, the risk was due to the presence of one
constituent, benzene, that was detected in only one of the five TCLP
samples. Thus, the constituent was not found frequently or typically in
this waste. Furthermore, EPA found none of the carcinogenic PAHs in
samples of this waste that were so pronounced in other wastes of
concern (e.g., CSO sediment).
9. Sludge From Sulfur Complex and Hydrogen Sulfide Removal Facilities
Summary
As proposed, the Agency is not listing as hazardous sludge from
sulfur complex and hydrogen sulfide removal facilities. No significant
risks were found for any exposure pathway from disposal in on-site or
off-site landfills, or in on-site and off-site LTUs, nor from potential
air releases from storage in dumpsters (well below 1E-6 in all cases).
In addition, the Agency noted that the sludges that may be generated
from treatment of this waste in the
[[Page 42163]]
primary wastewater treatment system are already listed. Furthermore,
the revised high-end risk analyses in the NODA in response to comments
also showed no significant risks for this waste (well below 1E-6 in all
cases). The few comments EPA received on this waste agreed with EPA's
decision not to list. Therefore, the Agency continues to believe that a
no-list decision is warranted and adopts the final decision
incorporating the reasoning in the preamble to the proposal.
10. Catalyst From Sulfur Complex and Hydrogen Sulfide Removal
Facilities
Summary
The Agency is not listing as hazardous any of the spent catalysts
generated from H2S removal and sulfur complex operations.
The Agency divided this residual into two subcategories: Spent Claus
unit catalyst, and spent SCOT-like tail gas catalyst. For the first
subcategory, no significant risks were found from bounding estimates
(run under worst-case assumptions using multiple high-end assumptions
for critical parameters) for the groundwater exposure pathway as well
as for the direct and indirect pathways of volatile emissions and
particulate emissions. For the second subcategory, the Agency also did
not find significant risks associated with the disposal of this waste
in on-site and off-site landfills. Furthermore, the revised risk
analyses in the NODA in response to comments continued to show no
significant risks for this waste stream. Therefore, the Agency
continues to believe that a no-list decision is warranted and adopts
the final decision incorporating the reasoning in the preamble to the
proposal.
11. Unleaded Gasoline Storage Tank Sediment
Summary
EPA is not listing as hazardous sediment from the storage of
unleaded gasoline in tanks. The Agency assessed the potential risks
associated with four selected management practices, on-site and off-
site Subtitle D landfilling, and on-site and off-site land treatment.
Only marginal risk was identified for the groundwater ingestion
exposure pathway. Although revisions to the risk assessment showed
higher risks above the level of concern, EPA has still decided not to
list this waste because: (1) The waste is primarily rust and scale and
has none of the carcinogenic PAHs or high oil content of potential
concern in other wastes, (2) the TC is expected to control some risks,
(3) the volume of waste is relatively small, and (4) the reduction of
benzene levels in reformulated gasoline should reduce levels in wastes
in the future.
Discussion
EPA proposed not to list unleaded gasoline tank sediment as
hazardous due to the absence of any significant risks, except for the
marginal risks found for the groundwater ingestion pathway for off-site
landfill disposal (high-end risk, 2E-6). The Agency also noted that
this waste was infrequently generated, volumes of this waste disposed
were relatively modest, and that the only constituent of concern,
benzene, would be controlled by the TC.
The revised modeling completed by EPA in response to comments on
the proposal and the NODA included a full sensitivity analysis to
determine the most critical high-end parameters, and resulted in off-
site landfill groundwater risks increasing to 3E-5 (see Table IV-2).
The high-end risk was lowered slightly to 2E-5 in the TC-capped
results. However, the revised Monte Carlo risk, 6E-6, is below EPA's
level of concern (1E-5), and the TC-capped Monte Carlo risks drop to
4E-6, suggesting the TC may control most risks of concern for this
waste. After considering these risk results, and the other factors
discussed below, EPA finds that the listing of this waste is not
warranted.
First, while the levels of benzene in the waste and TCLP samples
are of potential concern, the TC for benzene should provide some
measure of control of wastes with high benzene levels. Nearly 40
percent (52) of the 141 unleaded gasoline tank sediment wastes streams
generated in 1992 were reported in the 3007 Questionnaire to be coded
as hazardous waste (due primarily to the TC for benzene and
occasionally for ignitability). While EPA's risk analysis using TCLP
input data capped at the TC level still showed some risk (2E-5), many
of the wastes that are not TC-hazardous will likely have benzene levels
below the TC level. Thus, given the existing regulatory control
afforded by the TC, the incremental benefit to listing this waste
appears limited.
Furthermore, this waste does not have the features that EPA found
compelling in deciding to list other wastes examined in this rule.
Specifically, this waste lacks the pyrophoricity and arsenic concerns
exhibited by the spent catalysts, and it has low oil content and PAH
levels compared to the crude oil and CSO tank sediments. The oil
content of this waste is typically low as evidenced by the median TOG
levels reported in the 3007 Questionnaire (6 percent), and samples
taken by EPA (<1 percent). This contrasts with much higher TOG levels
in Crude Oil Storage Tank Sediment (34 percent average from the 3007
Questionnaire, and 21 percent average from the six samples EPA
analyzed) and CSO Tank Sediment (30 percent average from the 3007
Questionnaire, and 37 percent average from EPA's samples). EPA's
analyses of samples of unleaded gasoline storage tank sediments also
showed none of the carcinogenic PAHs that were of concern in sediment
from CSO and crude oil tanks. For example, average benzo(a)pyrene
levels found in sediment from CSO and crude oil storage were 132 ppm
and 12 respectively, but none was found in sediment from unleaded
gasoline storage. In addition, one of the major constituents measured
in the unleaded gasoline tank sediment was iron (e.g., the average iron
level for the three samples was 41, thus this waste appears to be
largely rust and scale, rather than the higher organic content of the
other tank sediments. Therefore, EPA is more confident that the other
constituents of gasoline tank sediment will not present any potential
problem.
Also, as noted in the proposed rule, the total volume of the waste
reported for 1992 is relatively small (3,583 MT), and the volumes sent
to landfills are even smaller (633 MT, 22 MT average per waste stream).
These volumes are significantly smaller than the volumes of crude oil
storage tank sediment generated (22,017 MT) and sent to landfills
(2,338 MT, 123 MT average).
Finally, EPA has promulgated regulations under the Clean Air Act
(CAA) that will result in the reduction of benzene levels in gasoline
(see the Reformulated Gasoline Rule, February 16, 1994; 59 FR 7716).
This rule sets a 1.0 percent (by volume) benzene limit on reformulated
gasoline for non-attainment areas of the United States. In conventional
gasoline, benzene is incorporated into gasoline to increase the octane
rating, and the average amount of benzene in conventional gasoline is
1.6 percent, ranging up to 5.0 percent. Therefore, as the levels of
benzene in gasoline are reduced, sediment from storage of gasoline
should also show a corresponding reduction in the levels of benzene.
This will reduce the potential groundwater risks resulting from benzene
in unleaded gasoline storage tank sediment.
Specific Comments
One commenter noted that EPA did not model the use of unleaded
gasoline tank sediment waste as landfill cover or road spreading. In
response, the Agency
[[Page 42164]]
points out that no refineries reported use of unleaded gasoline tank
sediment as landfill cover or in road spreading. The Agency has no data
supporting these management scenarios and therefore does not see the
need to model this pathway.
While the Agency already discussed the general issues related to
the appropriateness of the TCLP for the wastes examined in this
rulemaking due to oil content, EPA notes that for this specific waste
the total oil and grease levels in the available samples collected by
EPA were well below 1 percent. Thus, the commenter's concern about
problems with the TCLP and oily waste are clearly unfounded for this
waste.
One commenter criticized EPA's modeling of risks from LTUs, and
these are addressed elsewhere in today's notice (see Section V.B.7).
However, EPA would like to note that nongroundwater risks are unlikely
to be significant for this waste under any scenario because unleaded
gasoline tank sediment has none of the carcinogenic PAHs that were of
concern for other wastes, such as CSO.
One commenter argued that EPA should list this waste based on the
groundwater risks calculated by the commenter using alternative
groundwater modeling (8.8E-5). EPA disagrees with many of the
commenter's suggested modifications to the modeling (see Section V.B.6)
and continues to believe that the risks do not justify listing this
waste. As noted in the discussion above, EPA's revised high-end risk
was 3E-5, and the revised Monte Carlo risk was 6E-6 (see Table IV-2),
and after considering the other factors noted, EPA has decided not to
list this waste. Furthermore, the revised Monte Carlo risks for this
waste were 6E-6, below EPA's 1E-5 level of concern. In addition, the
Monte Carlo TC-capped risk of 2E-6 suggests that the TC will be
effective in controlling much of the risk for this waste.
12. Catalyst From Reforming
Summary
The Agency is not listing as hazardous spent catalyst from
reforming operations, as proposed. The proposal noted that 94 percent
of the wastes generated in 1992 were recycled at reclamation facilities
for the precious platinum content. The remaining 6 percent consist
primarily of other materials generated during catalyst replacement,
e.g., ceramic support media that are inert. The Agency conducted risk
analysis of the potential air exposure pathway from the combustion of
the reforming catalyst prior to reclamation, and no significant risk
was found from this pathway. In addition, the Agency believes generator
site environmental release other than potential de minimis spills would
be unlikely because the valuable spent reforming catalysts are
controlled and tracked between the refining and reclamation facilities
to prevent loss. The one comment EPA received on the Agency's
assessment agreed with the decision not to list. Therefore, the Agency
continues to believe that a no-list decision is warranted and adopts
the final decision incorporating the reasoning in the preamble to the
proposal.
13. Sludge From Sulfuric Acid Alkylation
The Agency is not listing as hazardous sludge from sulfuric acid
alkylation. In the proposal, the Agency noted that this waste was
infrequently generated, and the volumes generated in 1992 were very
small (608 MT). Based on the bounding estimates (run under worst-case
assumptions using multiple high-end assumptions for critical
parameters) conducted for land treatment and landfilling practices, no
significant risk was found. Furthermore, the revised land treatment
risk analyses in the NODA in response to comments showed no significant
risks for this waste stream. Therefore, the Agency continues to believe
that a no-list decision is warranted and adopts the final decision
incorporating the reasoning in the preamble to the proposal.
D. Headworks Exemption
As noted in Section III.A in the proposed rule, EPA proposed to
extend the existing exemption for wastewaters from cleaning of
petroleum tanks to include those generated for CSO tank sediment, and
if listed, crude oil storage tank sediment. In the NODA, EPA proposed
to extend the exemption to include wastewaters generated from the clean
out of processing units holding spent hydrotreating and hydrorefining
catalysts.
1. Application to Listed Catalysts
Many commenters requested clarification that the headworks
exemption would include wastewaters from spent hydrotreating and
hydrorefining catalysts. This would allow refiners to continue the
practice of using water to cool and wash out these spent catalysts from
the process units prior to further management. One commenter stated
that sufficient controls are in place within refineries to manage minor
residuals that are drained to the refinery sewer systems. These
residuals will be removed in the system and become listed hazardous
wastes. Without these exemptions, refiners would be forced to either
use more costly or more dangerous methods in managing catalyst or be
forced to collect and ship these wash waters off-site.
As described in the NODA, EPA considered the commenters' request
and conducted an assessment to determine the appropriateness of
expanding the headworks exemption. The results of this analysis show
that little risk is likely to be incurred by this practice. The use of
water during the catalyst changeout process provides a number of
benefits, including lowering emissions of volatile organics (if the
wash water is treated to remove volatiles prior to discharge to the
sewer system), lowering the risks associated with the catalysts'
potential self-heating nature, and minimizing risk to workers entering
the confined space of the catalytic reactors during changeouts.
Therefore, EPA, has concluded that it is appropriate to include this
low risk, beneficial practice under the headworks exemption.
Many commenters approved of expanding the proposed headworks
exemption to cover water associated with catalyst management. These
commenters saw the exemption as consistent with EPA's listing criteria
in 40 CFR 261.11(a)(3), and agreed with EPA that the exposure pathways
from wastewater management associated with CSO sediment and
hydroprocessing catalysts in the refinery wastewater treatment system
are sufficiently regulated under the Clean Water Act (CWA), the CAA
NESHAP, and the existing RCRA hazardous waste listing for refinery
wastewater treatment sludges (K048, K051, F037, and F038).
EPA agrees that existing NESHAP and effluent guideline controls on
these materials, as well as the existing sludge listings (F037, F038,
K048, K051), and the inherent differences between the wastes modeled
and the aqueous residuals generated during tank and unit washings,
support EPA's decision to finalize the headworks exemption.
2. Clarification of Scope
EPA received a request for clarification about whether the proposed
exemption is limited to dilute wastewaters resulting from the cleanout
of tanks or other units containing these wastes, or whether the
proposed exemption applies to the listed waste (sediment) itself. One
commenter stated that the exemption would be abused and would encourage
wholesale discharge of the sediments to the wastewater treatment
system. EPA
[[Page 42165]]
reiterates that the headworks exclusion is not meant to serve as an
incentive to discharge tank sediments (or spent catalyst) to the
wastewater treatment plant. This was not the Agency's intent, and EPA
requested comment in the NODA on how to ensure that the headworks
exemption is not a loophole to dump catalyst or CSO sediment in the
sewer.
One commenter argued that the exemption would not be a loophole for
two important reasons. First there would be a significant economic
penalty for this action, because solid material dumped in the sewer
will emerge again as hazardous waste sludges upstream of biological
treatment (F037, F038, K051 and K048). The commenter stated that any
wastewater sludge that these solids generate would likely be many times
the original weight of the solids in the water (up to 10-fold due to
the oil water-bacteria emulsion that forms around these solids). The
commenter claimed that the increased costs associated with increased
volumes of difficult to manage emulsions would be a severe economic
penalty for allowing excess solids into a sewer. Secondly, the
commenter noted that sewers are critical to a refinery's operation,
such that any discharge of solids into a sewer runs the risk of
interrupting refinery operations (with heavy costs), or at least
overloading the system with solids, endangering compliance with water
discharge permits. Therefore, the commenter concluded there is no need
for EPA to further define allowable wastewater solids content, and this
would only create unneeded analytical, record keeping, and related
compliance burdens.
The Agency agrees with this commenter that there are financial
disincentives to discharging excess solids to the refinery wastewater
treatment system. Furthermore, the Agency observes that many refineries
conduct deoiling of tank contents and sediments prior to disposal and
tank inspection. This practice reduces sediment quantities by an
average of 40 percent, with a substantial savings of raw materials
(i.e., oil recycled back to the refining operations) and disposal
costs. Upon promulgation of today's listings and the exclusion for oil-
bearing residuals, EPA believes even greater amounts are likely to be
subjected to oil recovery and waste minimization. Any water in the tank
clean out material will likely be separated as a part of the deoiling
process, and would be discharged to the wastewater treatment plant.
Thus, with respect to some commenters' concerns regarding impacts on
the wastewater treatment system, these recycling activities will likely
increase and further reduce the load on the treatment system.
A commenter asked EPA to clarify the scope of the exemption in the
final rule, since water is used in any number of different ways in the
proper handling of CSO sediment and spent hydroprocessing catalysts.
They stated that EPA should clarify in the final rule that the
exemption extends to all wastewaters derived from the management of the
residuals, as long as the wastewaters are managed in a system subject
to the Clean Water Act.
EPA is aware of the following uses of water associated with the
generation of K169 to K172. In reference to crude oil storage and CSO
tank sediments (K169 and K170), wastewater is generated (1) by
dewatering (e.g., centrifuging) sediment removed from the tank, and (2)
by conducting a ``rinse'' as mentioned by the commenter. In reference
to K171 and K172, wastewater is generated from drilling out the
catalyst, steam stripping or washing, and pad drainage.
EPA believes that the headworks exemption is appropriate for waters
generated from all of these practices, because these aqueous residuals
would be dilute and contain low levels of the original listed wastes.
Therefore, the Agency is finalizing the exemption for all the wastes
that are being listed: CSO sediment, crude oil sediment, spent
hydrotreating catalysts, and spent hydrorefining catalysts. As noted in
the proposal, however, the exemption is not intended to allow the
discharge of the entire waste stream (i.e., tank sediments or spent
catalysts), but rather dilute waters generated during tank or unit
clean outs and dewatering.
Another commenter requested clarification that the headworks
exemption extends to zero discharge facilities that have CWA equivalent
wastewater treatment units. The Agency wishes to clarify that the
exemption would extend to facilities subject to regulation under
section 402 or section 307(b) of the CWA and would include facilities
that have eliminated the discharge of wastewater. However, this
clarification is already included in the regulations in 261.3(a)(iv)
and specifies that wastewaters at facilities that have eliminated
discharges are included.
Facilities that elect to use the headworks exemption should
understand the potential compliance implications for Subpart FF, the
benzene waste operations NESHAP, (40 CFR 61.340). Subpart FF conditions
the need for air pollution controls and waste treatment on the total
annual benzene quantity (TAB) from a facility's waste. Facilities must
include any waste stream ``that has a flow-weighted annual average
water content greater than 10 percent or that is mixed with water or
other wastes at any time and the mixture has an annual average water
content greater than 10 percent.'' Since 1995, refineries with a TAB of
10 MT per year or greater must treat all benzene wastes and control
emissions from drains, sewers, tanks, oil-water separators,
impoundments, and containers. Thus, if facilities elect to use the
headworks exemption, any wastes put in sewers that did not previously
count toward the TAB will have to be included in TAB calculations. If
refineries have TAB that exceeds 10 MT/yr, they would be out of
compliance with Subpart FF.
3. Comments Opposing the Exemption
One commenter urged the rejection of EPA's proposal to exempt from
regulation previously listed refinery wastes (K050), CSO residuals, and
crude oil storage tank sediment, because it encourages waste
constituent volatilization and dilution, rather than pollution
prevention and responsible waste management. The commenter noted that
EPA's sole justification for the proposal was the Agency's belief that
the hazardous constituents in these wastes would wind up in RCRA
regulated wastewater treatment sludges. The commenter asserted that EPA
failed to address why hazardous constituents in the discharges would
not be released into the air, or remain in the wastewater and bypass
the primary sludge only to settle in the unregulated treatment sludges
further down the treatment train.
As noted earlier in today's notice (see discussion on Waste
Management Assumptions in Section V.B.2), EPA does not believe that
discharges to wastewater treatment systems are likely to present
significant risks. EPA also notes it did not find air releases of
volatiles, such as benzene, to be a significant risk for any of these
wastes for any disposal practice evaluated. Thus, EPA does not believe
that any air releases from a much more dilute waste generated during
tank or unit clean outs are likely to present significant risk. The
Agency notes that the benzene NESHAP (58 FR 3072; January 7, 1993)
provides significant control of emissions from the wastewater
conveyance system at larger refineries, and that the reported amount of
sediments managed in this manner is small relative to the total volume
of waste being given this exemption. Refineries also avoid overloads to
their biological treatment trains in order to maintain their
effectiveness.
[[Page 42166]]
EPA also notes that the discharge of aqueous wastes generated
during tank cleaning are generated only infrequently. EPA's data from
the 3007 Questionnaire, shows that, on average, a single CSO tank is
cleaned every 9 years and, on average, a refinery has four tanks
containing CSO (for those that generate the residual). Therefore, a
typical refinery generates CSO tank cleaning wastewaters less than once
per year. Discharges of tank cleaning waters are infrequent and are
expected to generate relatively small volumes of water in comparison
with the typical wastewater flow through a refinery treatment system
(see analysis noted below).
Tank cleanings are used to facilitate tank inspections, which are
critical to ensuring tank integrity and to avoiding catastrophic tank
failure. Without this exemption, tank washing would become much more
difficult because of the need to find alternative Subtitle C disposal
methods for these wastewaters. Also, the tank washings are dramatically
different in nature from the sediments characterized for the listing
determination. While these washes are primarily water, the sediments
are primarily solid, subject to land disposal methods such as the
landfilling and land treatment evaluated in EPA's risk assessment.
To respond fully to this commenter, EPA presented a further
analysis in the NODA to illustrate the magnitude of treatment and
dilution that would occur at the headworks of a refinery for both CSO
tank sediment and spent hydrotreating/hydrorefining catalysts. (See
Sections 8 and 9 in Supplemental Background Document-Listing Support
Document, March 1997). EPA notes that it completed a similar analysis
for crude oil storage tank sediment to respond to the commenter's
concerns expressed about this waste also (see Additional Listing
Support Analysis, 1998 in the docket). EPA concluded from these
analyses that any impact on the downstream wastewater treatment sludge
or wastewaters would be negligible.
Comments on the NODA analysis for the headworks exemption argued
that EPA based the assessment for CSO sediment on disposal of the waste
itself in the wastewater treatment system, and that the exemption
should be limited to dilute wastewaters. The commenter suggested that
EPA set limits on maximum concentrations for contaminants in
discharges, and limit the exemption to rinsate from the cleaning of
tanks or other units. The commenter stated that these limitations
should also apply to the existing exemption for heat exchanger bundle
cleaning sludge, currently listed as hazardous waste K050, because the
existing exemption suffers from the same flaws as the proposal. The
commenter also indicated that if EPA does not limit the exemption to
rinsate, the CSO assessment is flawed because it was based on the waste
volume of the one facility reporting waste discharge into a wastewater
treatment system in 1992. The commenter recognized that the facility no
longer intends to employ the practice, but argued the potential exists
for any generator of the waste to do so.
In response, EPA notes that the purpose of the NODA exercise was to
develop a ``what if'' scenario, representing the extreme case of CSO
washwater loading to wastewater treatment. EPA concluded that because
its ``what if'' scenario showed negligible risk, then no specific
restrictions on washwater composition would be required. Furthermore,
as discussed above in this section, EPA believes that there are
significant disincentives for refineries to discharge high solids
content waste to their wastewater treatment system. Finally, EPA notes
that the existing exemption for heat exchanger bundle cleaning sludge
(K050) was not explicitly reopened for comment, therefore the Agency is
not considering any modification of this exemption in today's rule.
Certainly, on-site wastewater treatment systems are available for
this purpose throughout the refinery industry. EPA based its
evaluations on the actual waste quantities used in particular
management scenarios. EPA has no reason to believe, for example, that a
quantity of waste destined for land treatment would be managed in a
wastewater treatment system. EPA points out that a significant fraction
of the wastes being listed must already be handled as hazardous,
because they exhibit the TC or other characteristics. Yet despite this
apparent incentive to avoid costly Subtitle C management, the disposal
of tank sediment directly into the wastewater treatment system was
extremely rare (i.e., only once each for CSO and crude oil storage tank
sediments).
The commenter also questioned whether the Agency accurately
estimated the impact posed by the exemption, because EPA ignored the
possibility that contaminants from other wastes and wastewaters would
be codisposed with the potentially exempt waste in the wastewater
treatment system. In response, EPA notes that its analysis was an
attempt to gauge the significance of a worst-case discharge into the
treatment system to determine if any significant incremental risks
would result from the practice. EPA found no such incremental risks and
therefore concluded that the exemption was appropriate. In fact, EPA
found that risks due to the exempted wastes would be extremely small.
The commenter expressed concern that the exemption would likely be
encouraging the generation of larger quantities of hazardous wastewater
treatment sludge, which would be incompatible with the waste
minimization policy and objectives articulated by Congress in Section
1003 of RCRA.
In response, EPA believes that refineries have no incentive to
discharge solids to wastewater treatment, because the solids would end
up as F037 or other hazardous waste. As discussed above, other comments
noted that the quantity of such primary sludge would be much greater
than the quantity of solids initially dumped into the system.
E. Third Party Recycling of Spent Petroleum Catalysts
In the November 20, 1995 proposal, the Agency suggested that it
might be appropriate to exempt these thermal petroleum catalyst
recovery units from RCRA Subtitle C regulation. The Agency solicited
important additional information needed to adequately assess the basis
for promulgating this potential exemption (see 60 FR at 57780). This
information included the extent to which petroleum catalyst recovery
units are currently equipped with emission control devices, the
adequacy/efficiency of existing controls, and the amounts and
concentrations of emissions of HAPs regulated under section 112 of the
CAA as well as under Subtitle C of RCRA. (Id.)
The Agency's preliminary findings in 1995, based on very limited
data, indicate that these units may already be equipped with pollution
controls comparable to those required under RCRA regulations for
boilers and industrial furnaces (BIFs) that burn hazardous waste.
However, EPA pointed out in 1995 the importance and need for additional
air emissions data, in particular, information on the types and levels
of HAPs being emitted from these offsite hazardous waste reclamation
and regeneration units. (Id.)
No information on these key factors was forthcoming on these units.
Only one facility submitted a copy of its state air permit. The nature
of, and data associated with, this facility's state permit are much too
limited to provide an adequate record for the Agency to make a
determination on whether to
[[Page 42167]]
exempt from RCRA controls this entire class of reclamation and
regeneration units. The information in the permit is manifestly
insufficient for such a determination. Even if it were more complete,
EPA could likely not extrapolate the information from this single
facility to all thermal units with an adequate degree of confidence.
For instance, the permit contains limits only on emission rates of CAA
criteria air pollutants carbon monoxide (CO), sulfuric oxides
(SOX), nitrogen oxides (NOX), particulate matter
(Method 10) (PM10), and volatile organic constituents
(total-VOCs) on an average annual basis. Daily/hourly mass discharge
rates or concentrations for these pollutants were lacking, as was any
information on HAPs of concern under Section 112 of the CAA (and,
because of their hazardousness, under RCRA as well), or the means by
which such HAPs might be controlled. Also, this permit report lacks
information on the destruction and removal efficiency (DREs) that the
combustion unit can achieve for potential principal organic
constituents (POCs) fed to the regeneration process (see 40 CFR
266.104(2)). Finally, the permit report lacks information on the kind
of controls for metal emissions as well as the types and levels of
metals being emitted.
EPA has no additional data on similar units and on the key factors
to be considered in determining whether to finalize the proposed
exemption. At this point, therefore, the administrative record for this
rule is simply not sufficient to support a final decision one way or
the other.
Given the current state of the administrative record and the other
circumstances discussed above, EPA is deferring to a later day any
final decision on whether or not to exempt these units from RCRA
Subtitle C air emission standards. The timing of this decision depends,
in large part, on the gathering and submittal of additional data on the
key factors identified above, especially the types and levels of HAP
emissions from these units and the adequacy of air pollution controls
for these emissions.
EPA encourages owners and operators of these facilities to
supplement the record with design, operation, and emissions information
so that further progress toward a final determination on the potential
exemption can be made. In the interim, EPA reiterates that nothing in
today's rule (or indeed the proposed rule) changes the current RCRA
status of facilities managing these hazardous wastes.
VI. Land Disposal Restrictions
A. Treatment Standards for Newly Identified Wastes
The land disposal prohibition statutory provisions essentially
require pretreatment of hazardous wastes so that threats to human
health and the environment posed by land disposal of the waste are
minimized (RCRA sections 3004(g)(4) and (m)). Land disposal
prohibitions for hazardous wastes are to be promulgated pursuant to a
phased schedule, the determination for newly listed wastes-those listed
after adoption of the 1984 amendments-to be made within six months of
promulgation of the listing (RCRA section 3004(g)(4)); see generally,
55 FR 22523, June 1, 1990.) A determination to prohibit hazardous
wastes from land disposal is essentially automatic, since only land
disposal that satisfies the exacting statutory no-migration standard
may be disposed without first satisfying the section 3004 (m) treatment
standards. (Id). A method of land disposal may not be determined to be
protective of human health and the environment until the waste has
complied with 3004(m) pretreatment regulations, unless upon application
of an interested person, it has been demonstrated to the Administrator,
to a reasonable degree of certainty, that there will be no migration of
hazardous constituents from the disposal unit or injection zone for as
long as the wastes remain hazardous (RCRA section 3004(d)). No one
contends that disposal of the petroleum wastes listed in this
rulemaking satisfies the no-migration standard.
EPA has traditionally developed treatment standards for prohibited
hazardous wastes based upon the performance of BDAT. The Agency further
refined this approach to use the same set of technology-based numerical
treatment standards whenever factually justified. These are the so-
called UTS set out in Sec. 268.48, which provide numerical treatment
standards for all hazardous constituents (i.e., constituents listed in
Appendix VIII of Part 261).
As part of the proposed rule, EPA proposed to apply the UTS
applicable to the hazardous constituents in the newly listed petroleum
refining industry wastes (see 60 FR 57783, November 20, 1995). EPA
further requested data to adjust the numerical treatment standards
applicable to the subject wastes to be consistent with the revisions to
the UTS being considered in the Agency's Phase IV Land Disposal
Restrictions rulemaking (see 62 FR 16751, April 8,1997). EPA has in
fact recently slightly amended the treatment standards for the
hazardous constituents antimony (see 63 FR 28562, May 26, 1998) and
nickel (see 63 FR 28569, May 26, 1998). EPA also has amended the
treatment standard for vanadium, which is not an underlying hazardous
constituent (40 CFR 268.2(i)), but is being regulated in these wastes
for the reasons given below. The constituents of concern as proposed
and the treatment standards as revised are being promulgated for the
newly identified K169, K170, K171, and K172 wastes. In accordance with
section 3004(g)(4), EPA is also prohibiting the underground injection
of these wastes (unless the wastes meet the treatment standard before
injection without being diluted impermissibly, or unless the wastes are
injected into a no-migration unit). Since underground injection is a
type of land disposal (see section 3004(k)), this action is automatic,
and implements the mandatory directive to prohibit land disposal of
newly listed hazardous wastes found in section 3004(g)(4).
B. Response to Comments
Additional comments, along with EPA's responses, are provided in
the Response to Comments Background Documents for the proposed rule and
the NODA located in the docket for this rule. Key comments are
discussed below.
1. Constituents of Concern
EPA received comment asking that, if listed, the LDR constituents
of concern should be limited to benzene and arsenic. The commenter
determined that these are the only two compounds which have significant
risk associated with their management. The commenter maintains that the
inclusion of the PAH compounds and other metals is not warranted and
will require additional cost to characterize the material prior to
management, and that their inclusion may prevent beneficial recycling
practices due to unnecessary LDR requirements on reclaimer residuals.
The Agency disagrees. EPA is required by statute to set ``...levels
or methods of treatment, if any, which substantially diminish the
toxicity of the waste or substantially reduce the likelihood of
migration of hazardous constituents from the waste so that short-term
and long-term threats to human health and the environment are
minimized'' (RCRA section 3004(m), 42 U.S.C. 6924(m)). While the
commenter is correct in that for K171 and K172 only benzene and arsenic
were given as the basis of listing, treatment standards were also
proposed for additional metals and PAHs. PAH compounds are highly
carcinogenic, even at low
[[Page 42168]]
concentrations, and are present at significant concentrations in some
petroleum residuals at levels exceeding the treatment standards.
Although these constituents were not modeled to show significant risks
through the pathways considered, the presence of these carcinogens in
the wastes remains a potential threat to human health and the
environment when the wastes are land disposed. Certainly, there is no
basis for finding that threats posed by these constituents have been
minimized without treatment (see Chemical Waste Management v. EPA, 976
F.2d at 16.) The Agency also notes that treatment standards for PAHs
and nickel are currently required for other similar listed petroleum
wastes (F037, F038, and K048-K052) and that damage cases associated
with these wastes have noted environmental effects due to both metals
and PAHs (see Background Document to Support Listing of Primary Oil/
Water Separation Sludges, August 20, 1990, pages 6-8 ). Thus, the
Agency is convinced that treatment of these constituents is necessary
to minimize threats posed by the wastes' land disposal, and further
convinced that the treatment standards are not established below levels
at which such threats are minimized. The Agency is therefore
promulgating treatment standards for all the constituents that were
proposed to be regulated.
2. Sulfides
The commenter recommended that if a new treatment standard for K171
and K172 is adopted, it must include a concentration level for
sulfides. The commenter believes a level of 500 ppm reactive sulfide
should be specified as an exit level for land disposal restrictions,
because the level has been used in Agency guidance to identify wastes
that exhibit a hazardous waste characteristic for reactive sulfides as
per OSWER policy memorandum No. 9443.1985(04). The commenter believes
that without a numerical treatment level, the regulated community may
be held to a double standard of having to meet the treatment standards
for both a Listed Waste and a Characteristic Waste.
EPA responds by clarifying that those K171 and K172 wastes that
exhibit the hazardous waste characteristic of reactive sulfide are
currently prohibited from land disposal unless first being treated to
remove the characteristic by deactivation. Underlying hazardous
constituents also must be treated (see existing Sec. 268.35
(prohibition on land disposal of reactive hazardous wastes) and
Sec. 268.40 (e) (underlying hazardous constituents in reactive wastes
must also be treated). Furthermore, even after the listing takes
effect, listed wastes may also exhibit one or more characteristics of a
hazardous waste. Listed wastes which also exhibit characteristics of a
hazardous waste must comply with all applicable treatment standards for
characteristic wastes (unless the treatment standard for the listed
waste contains a standard for the constituent that causes the waste to
exhibit a characteristic; see Sec. 268.9(b)). Finally, treatment must
reflect the ``minimize threat'' level for land disposal (3004 (d)(1)
and (g)(4) (land disposal is prohibited ``unless the Administrator
determines the prohibition on one or more methods of land disposal of
such waste is not required in order to protect human health and the
environment...''), and so may require treatment of constituents not
technically hazardous constituents, but which make a waste more
dangerous to land dispose (see 56 FR at 41168 (Aug. 19, 1991) and other
sources there cited). Thus, although sulfides are not hazardous
constituents (since they are not listed in Appendix VIII of Part 261),
they nevertheless are present in these wastes at concentrations
sufficient to provide harmful properties, including self-heating
pyrophoric properties and potential reactivity which must be minimized
for safe disposal (See 60 FR 57783-57785).
As a point of clarification, the newly listed K171 and K172 wastes,
which also are reactive, would have to comply with the UTS numerical
levels for the specified hazardous constituents and deactivation for
reactive sulfide prior to land disposal, but would not have to
demonstrate compliance with all the underlying hazardous constituents
(see Sec. 268.9 (b)). This is because the treatment standard itself
already indicates what other constituents are present in these wastes
requiring treatment so as to minimize threats posed by the wastes' land
disposal. The Agency will continue to determine if a separate UTS
number is required to access the deactivation of sulfide from reactive
wastes and, if so, will propose a number in the future.
3. Underlying Hazardous Constituents
A commenter stated that EPA should not subject listed hazardous
wastes to LDR regulations regarding Underlying Hazardous Constituents
(UHCs). The Agency wishes to clarify that listed wastes are not subject
to UHCs per se. UHCs are regulated in characteristic wastes (40 CFR
268.1). Listed wastes are regulated for the constituents which caused
the waste to be listed and any other hazardous constituents specified
in the specific treatment standard that are found to be present at
levels where they could possibly cause harm to human health and the
environment when the wastes are land disposed (see also discussion in
the preceding paragraph). The basis for the distinction is that EPA has
already studied the listed wastes to determine the hazardous
constituents that are typically present, but is unable to do so for
characteristic wastes, since, as a class, they are much more diverse.
The Agency is promulgating treatment standards for each of the proposed
hazardous constituents.
4. High Temperature Metals Recovery
EPA received comments suggesting the designation of High
Temperature Metals Recovery (HTMR) as an exclusive method of treatment.
The Agency has finalized numerical standards for the newly listed
wastes. Treaters may use any method they choose to achieve those
standards, so long as the treatment is not considered impermissible
dilution. The Agency believes this degree of flexibility is highly
desirable to provide as many treatment options as possible, so long as
the treatment satisfies the standards.
In the case of the vanadium containing K171 and K172 wastes, metals
recovery may be required to reduce the constituent to levels that can
be subsequently treated to comply with the LDR treatment standard.
Vanadium treatment is discussed more fully in the following section.
5. Vanadium
Vanadium is not an underlying hazardous constituent of hazardous
wastes that requires treatment in all characteristically hazardous
wastes. (see 268.48 note 5). However, vanadium in the form of ammonium
vanadate or vanadium pentoxide, are underlying hazardous constituents
(since they are included in Appendix VIII of Part 261). In the course
of the combustion of coke residues on the spent catalysts, vanadium
compounds adsorbed on the catalysts are converted to vanadium pentoxide
and the wastes are typically subjected to metals recovery for the
vanadium pentoxide. Because the presence of vanadium pentoxide would
impart acute toxicity to the wastes and can be readily measured as the
vanadium metal, the Agency proposed treatment standards for vanadium as
a constituent of concern in K171 and K172 as a surrogate measure to
limit the presence of vanadium pentoxide in the wastes and to insure
that the toxicity of the waste was diminished prior to disposal (see
also 60 FR 57784, November 20, 1995). Without reduction
[[Page 42169]]
of their vanadium content, the K171 and K172 wastes would contain
significant levels of vanadium in the form of toxic vanadium pentoxide.
Commenters claimed that the proposed treatment standard for
vanadium is not feasible and appropriate, based on EPA's testing. In
response, EPA evaluated additional data from the stabilization of
wastes containing vanadium at levels below which metals recovery is
feasible and, based on this data, calculated a standard of 1.6 mg/L
TCLP for nonwastewaters. The Agency proposed that this higher standard
replace the 0.23 mg/L TCLP standard originally proposed and believes
that this standard is readily achievable (see 62 FR 26047, May 12,
1997). A facility unable to comply with the treatment standard may
apply for a treatability variance under 40 CFR 268.42 (assuming the
waste has been treated using the properly-operated technology on whose
performance the treatment standard is based and is still unable to meet
the treatment standard).
One commenter claims that the Agency incorrectly assumed that spent
catalysts and their residuals are physically and chemically similar to
K048-K052 and K061 wastes. The commenter noted that the chemical
composition of K048-K052 and K061 wastes is quite different than that
of the K171 and K172 spent catalysts. The commenter identified other
physical differences between spent catalysts and K048-K052 and K061
wastes, and argued such differences apparently prevent the
stabilization of vanadium in spent catalysts.
The commenter is correct that the residuals are chemically and
physically quite different at their respective points of generation,
the principal difference is the higher concentration of vanadium in
K171/K172. However, both K061 and K171/K172 contain similar
constituents of concern which are largely metal oxides once K171/K172
is deactivated. Data assembled by the commenters show that K048-K052
contain 1-350 ppm vanadium and that K061 concentrations range from 0-
830 ppm, while vanadium in K171 ranges from 10-3300 ppm and, in K172,
vanadium ranges from 25-31000 ppm. The commenter also states that K172
has been observed as high as 150,000 ppm vanadium and notes that after
deactivation to remove the D003 characteristic, the vanadium present is
highly leachable. However, the commenter presents data reflecting
attempts to stabilize the deactivated waste with cement and lime,
rather than proceeding through the reclamation of a vanadium pentoxide
product normally produced by metal reclaimers. The Agency maintains
that following such reclamation, the treated waste would be very
comparable to K046-K052 and K061 in vanadium content since little
vanadium would remain. Data from reclaimers indicate that these
processes recover over 90 percent of the vanadium present. Without such
reclamation, it would be unlikely that high vanadium wastes, like K171/
K172, could be stabilized to the UTS level. The level of vanadium
remaining after reclamation would still require stabilization to reduce
the mobility of the toxic forms of vanadium. The Agency believes the
vanadium UTS level can be achieved, therefore, through proper treatment
which includes a reclamation step. Data on stabilization alone for high
vanadium wastes do not reflect proper and effective treatment, and the
Agency therefore is not compelled to modify the level based on this
data.
One commenter asserted that the treatment standard for vanadium
could not be rationally based on International Mill Service (IMS) K061
data and, to the extent that the standard could be based on INMETCO's
K061 waste, the standard cannot be automatically transferred to spent
catalysts because the resulting standards would not be achievable. The
Agency responds that the prior treatment standard for vanadium was
based on data obtained from IMS's HTMR facility. As revised in the
recent Phase Four LDR Rule, the vanadium standard is derived from
stabilization data. The performance levels promulgated were achievable
by the other facilities from whom the Agency had also collected data
(see 59 FR 47980, September 19, 1994). The Agency believes that the
residuals following vanadium metal recovery of the K171 and K172 wastes
can achieve the treatment standards measured on the basis of vanadium
and provide protection against the significant presence of acutely
toxic vanadium pentoxide in the land disposed waste. The commenter
provided no data demonstrating that the treatment standards could not
be met when metals recovery is performed.
6. Revisions to Proposed Standards
The Agency requested data to adjust the numerical treatment
standards applicable to the petroleum wastes subject of this rulemaking
to be consistent with the treatment standards proposed in the Phase IV
Land Disposal Restrictions (see 62 FR 26041, 26047-26048; May 12,
1997). Commenters supported the proposed revisions to the treatment
standards. In each case, the proposed standards reflect the higher of
the stabilization-based or HTMR-based calculations, in order to provide
flexibility to use various well-performing treatment technologies which
substantially reduce toxicity or mobility of hazardous constituents.
The commenter believes the revised treatment standards that EPA has
proposed for antimony, nickel, and vanadium are supported by the
underlying data and are achievable by both major treatment
technologies.
The Agency concurs with the commenters and also believes the BDAT
methodology has been properly applied to the available data to
calculate the revised treatment standards and that the levels are
achievable by both major treatment technologies. Based on data
submitted in the Phase IV rulemaking for nonwastewaters, the treatment
level for antimony is finalized at 1.15 mg/L TCLP, the treatment level
for nickel is finalized at 11.0 mg/L TCLP, and the treatment standard
for the vanadium, which is applicable only to K061, K171, and K172 as a
constituent of concern in these wastes, is finalized at 1.6 mg/L TCLP.
The Agency is therefore promulgating these standards consistent with
the levels finalized in the Phase Four Rulemaking. All other standards
are promulgated as proposed.
C. Capacity Determination for Newly Identified Wastes
1. Introduction
This section summarizes the results of the capacity analysis for
the wastes covered by today's rule. For a detailed discussion of
capacity analysis-related data sources, methodology, and detailed
response to comments for each group of wastes covered in this rule, see
the following document: ``Background Document for Capacity Analysis for
Land Disposal Restrictions: Newly Identified Petroleum Refining Process
Wastes (Final Rule)'' (i.e., the Capacity Background Document).
EPA's decisions on whether to grant a national capacity variance
are based on the availability of alternative treatment or recovery
technologies. Consequently, the methodology focuses on deriving
estimates of the quantities of waste that will require either
commercial treatment or the construction of new on-site treatment or
recovery as a result of the LDRs. The resulting estimates of required
commercial capacity are then compared to estimates of available
commercial capacity. If adequate commercial capacity exists, the waste
is restricted from further land disposal before meeting the LDR
treatment standards. If adequate capacity does not exist, RCRA
[[Page 42170]]
section 3004(h)(2) authorizes EPA to grant a national capacity variance
for the waste for up to two years or until adequate alternative
treatment capacity becomes available, whichever is sooner.
2. Capacity Analysis Results Summary
For this capacity analysis, EPA examined data on waste
characteristics and management practices that have been gathered for
the petroleum refining industry study in the 1992 RCRA Section 3007
survey. The Agency analyzed the capacity-related information from the
survey responses, reviewed the public comments received in response to
the proposed rule, contacted several commenters to obtain more specific
information, and identified the following annualized quantities of
newly identified hazardous wastes requiring commercial treatment: 4,400
tons of K169; 3,200 tons of K170; 3,400 tons of K171; and 7,400 tons of
K172. The available data sources indicate that there are no quantities
of K169-K172 wastewaters that will require alternative commercial
treatment.
EPA is finalizing the rule to apply UTS to these wastes. The
treatment standards for nonwastewaters containing organic constituents
are based on combustion. The Agency determined that the available
combustion capacity to treat these wastes far exceeds the waste
quantities requiring alternative treatment when the listing
determinations for these wastes become effective. Also, the Agency
recognizes that the treatment residuals from these wastes may require
additional treatment capacity (e.g., stabilization) to achieve the UTS
for metal constituents. The Agency estimated that there several million
MT per year of available commercial stabilization capacity. EPA also
identified several metal recovery technologies that are commercially
available, and some of these technologies are being used currently by
the petroleum refining industry to recycle K171 and K172, although
permitting and regulatory concerns expressed by some catalyst recyclers
may need additional time to upgrade or expand their storage units.
Since EPA is finalizing numerical standards for these wastes, all the
technologies capable of achieving the final LDR treatment standards are
not prohibited. Sufficient alternative treatment or recovery capacity
exists to treat these wastes to meet the LDR standards. Therefore, EPA
is not granting a national capacity variance under LDR for these
wastes. The LDR standards for these wastes will become effective when
the listings become effective.
For soil and debris contaminated with the newly listed wastes, EPA
proposed to not grant a national capacity variance. EPA received no
comments regarding this issue. EPA believes that the majority of
contaminated soil and debris will be managed on-site and therefore
would not require substantial off-site commercial treatment capacity.
Therefore, EPA is not granting a national capacity variance to
hazardous soil and debris contaminated with the newly listed wastes
covered under this rule. Based on the questionnaire, there were no data
showing the mixed radioactive wastes with the newly listed wastes.
There were also no comments concerning the radioactive wastes mixed
with the newly identified wastes. EPA is not granting a national
capacity variance for mixed radioactive wastes or soil and debris
contaminated with these mixed radioactive wastes.
EPA received comments concerning the availability of treatment and
recovery capacity. One commenter requested a six-month delay in the
effective date of the final rule, and two commenters requested that EPA
grant a one- to two-year capacity variance to obtain permit
modifications and construct any necessary plant upgrades. Commenters
requested additional time to comply with various Subtitle C
requirements, particularly relating to permitting and upgrading of
areas used for storing K171 and K172 prior to the catalyst recycling
process. Commenters requesting a two-year capacity variance for
recycling facilities expressed concern about the potential economic
impact on the facilities the Agency is relying on to provide the
required treatment capacity. The commenters noted that, if promulgated
as proposed, the Agency's listing would also mandate the application of
the ``mixture'' and ``derived from'' rule for all management activities
after the point of generation, placing additional regulatory burden
(LDR treatment standards, upgrading of storage areas, potential Subpart
CC compliance, and obtaining permits/variances) on environmentally
sound management practices.
Based on the results of the Agency's capacity analysis, adequate
commercially available treatment or recovery capacity does currently
exist for K171 and K172 wastes. Furthermore, granting a national
capacity variance only exempts the waste from treatment standards prior
to land disposal during the variance period, but does not exempt the
waste from other Subtitle C requirements, such as the requirement to
have a permit for storage of hazardous waste for greater than 90 days
(at generator's sites). EPA believes that six months is sufficient to
allow facilities to determine whether their wastes are affected by this
rule and identify and locate alternative treatment or recovery capacity
if necessary. Therefore, LDR treatment standards will become effective
when the listing determinations become effective for the wastes covered
under this rule (see RCRA section 3004(h)(1)(land disposal prohibitions
must take effect immediately when there is sufficient protective
treatment capacity for the waste available).
VII. Compliance and Implementation
A. State Authority
1. Applicability of Rules in Authorized States
Under section 3006 of RCRA, EPA may authorize qualified States to
administer and enforce the RCRA hazardous waste program within the
State. (See 40 CFR Part 271 for the standards and requirements for
authorization.) Following authorization, EPA retains enforcement
authority under Sections 3007, 3008, 3013, and 7003 of RCRA, although
authorized States have primary enforcement responsibility.
Before the Hazardous and Solid Waste Amendments of 1984 (HSWA)
amended RCRA, a State with final authorization administered its
hazardous waste program entirely in lieu of the Federal program in that
State. The Federal requirements no longer applied in the authorized
State, and EPA could not issue permits for any facilities located in
the State with permitting authorization. When new, more stringent
Federal requirements were promulgated or enacted, the State was
obligated to enact equivalent authority within specified time-frames.
New Federal requirements did not take effect in an authorized State
until the State adopted the requirements as State law.
By contrast, under section 3006(g) of RCRA, 42 U.S.C. 6926(g), new
requirements and prohibitions imposed by the HSWA (including the
hazardous waste listings finalized in this notice) take effect in
authorized States at the same time that they take effect in non-
authorized States. While States must still adopt HSWA-related
provisions as State law to retain final authorization, EPA is directed
to implement those requirements and prohibitions in authorized States,
including the issuance of permits, until the State is granted
authorization to do so.
Authorized States are required to modify their programs only when
EPA
[[Page 42171]]
promulgates Federal standards that are more stringent or broader in
scope than existing Federal standards. Section 3009 of RCRA allows
States to impose standards more stringent than those in the Federal
program. See also 40 CFR 271.1(i). For those Federal program changes,
both HSWA and non-HSWA, that are less stringent or reduce the scope of
the Federal program, States are not required to modify their programs.
Less stringent regulations, both HSWA and non-HSWA, do not go into
effect in authorized States until those States adopt them and are
authorized to implement them.
2. Effect on State Authorizations
Today's rule is promulgated pursuant in part to HSWA authority and
in part pursuant to non-HSWA authority. The listing of the new K wastes
is promulgated pursuant to RCRA section 3001(e)(2), a HSWA provision.
Therefore, the Agency is adding this rule to Table 1 in 40 CFR
271.1(j), which identifies the Federal program requirements that are
promulgated pursuant to HSWA and take effect in all States, regardless
of their authorization status. The land disposal restrictions and the
UTS for these wastes are promulgated pursuant to RCRA Section 3004(g)
and (m), also HSWA provisions. Table 2 in 40 CFR 271.1(j) is modified
to indicate that these requirements are self-implementing. States may
apply for either interim or final authorization for the HSWA provisions
in 40 CFR 271.1(j), as discussed below.
Until the States receive authorization for these more stringent
HSWA provisions, EPA will implement them. EPA will also implement the
exemptions that are directly related to the new listings, such as the
headwork exemption and the catalyst support media exemption. These
exemptions are relevant only when regulating the newly listed wastes.
Today's rule also includes several non-HSWA provisions that reduce
the scope of the Federal program. These are the exclusions from the
definition of solid waste of certain oil-bearing hazardous secondary
materials from petroleum refining and certain recovered oils from
associated petrochemical facilities. Although the States do not have to
adopt these provisions, EPA strongly encourages them to do so, because
the exclusions encourage material recovery within those industries.
Today's revision to the listing description for F037 wastes at
Sec. 261.31 neither broadens nor narrows the scope of the current
program. This revision was made to ensure that residuals derived from
recycling listed wastes, that are otherwise excluded under today's
revised Sec. 261.4(a)(12), would remain listed. Because today's
revision to the F037 waste code only applies in situations where the
exclusion at Sec. 261.4(a)(12) applies, these provisions (the exclusion
and the associated revised listing) should be adopted together, and
taken together are considered to reduce the scope of the existing
Federal requirements.
Today's rule also amends the existing regulations to clarify that
certain spent caustic solutions used as feedstock are not solid waste.
This clarifying amendment (40 CFR 261.4(a)(19)) does not change the
scope of the RCRA program because it does not actually change the
current definition of solid waste. States do not need further
authorization to interpret their regulations in accordance with this
clarification.
Lastly, regarding the non-HSWA amendments to the definition of
solid waste (i.e., exclusions), a number of States qualified for final
authorization prior to being required to adopt the redefinition of
solid waste rulemaking of January 4, 1985 (50 FR 614). Since the
January 4, 1985, rule is more stringent than the rule under which such
States were authorized, such States were required to revise their
programs in accordance with Sec. 271.21. Today's changes will not
preclude EPA's ability to authorize States which have subsequently
adopted the January 4, 1985, rule since it would reduce the scope of
the Federal requirements. However, certain aspects of the State's
regulation will be broader in scope than the Federal program and
therefore not part of the authorized State program. This means that
while they are enforceable under State law, they are not subject to
Federal regulatory enforcement.\25\
---------------------------------------------------------------------------
\25\ Today's rule affects only the regulatory definition of
solid waste. It does not interpret the term ``solid waste'' for
purposes of the non-regulatory authorities in RCRA sections 3007,
3013, 7002, and 7003. thus, for purposes of those authorities, the
Agency would have the benefit of the full jurisdictional reach of
the statutory definition of solid waste. See Connecticut Coastal
Fishermen's Association v. Remington Arms Co., 989 F2d 1305, 1314-15
(2d. Cir. 1993) (comparing the narrower regulatory definition of
solid waste for determining the scope of Subtitle C regulation with
the broader statutory definition); Comite. Pro Rescate de la Salud
v. Puerto Rico Aqueduct and Sewer Authority, 888 F.2d 180, 187 (1st
Cir. 1990) (noting that under RCRA EPA could implement two different
definitions of solid waste: a broader definition for imminent and
substantial endangerment authority and a more narrow definition for
regulatory purposes).
---------------------------------------------------------------------------
A State submitting a program modification for the portions of this
rule promulgated pursuant to HSWA authority may apply to receive either
interim authorization under RCRA section 3006(g) or final authorization
under 3006(b), if the State requirements are, respectively,
substantially equivalent or equivalent to EPA's requirements. States
can only receive final authorization for program modifications
implementing non-HSWA requirements. The procedures and schedule for
final authorization of State program modifications are described in 40
CFR 271.21. It should be noted that all HSWA interim authorizations are
currently scheduled to expire on January 1, 2003 (see 57 FR 60129,
February 18, 1992).
Section 271.21(e)(2) of EPA's State authorization regulations (40
CFR part 271) requires that States with final authorization modify
their programs to reflect Federal program changes and submit the
modifications to EPA for approval. The deadline by which the States
must modify their programs to adopt this regulation is determined by
the date of promulgation of a final rule in accordance with section
271.21(e)(2). Table 1 at 40 CFR 271.1 is amended accordingly. Once EPA
approves the modification, the State requirements become RCRA Subtitle
C requirements.
States with authorized RCRA programs already may have regulations
similar to those in this rule. These State regulations have not been
assessed against the Federal regulations being finalized to determine
whether they meet the tests for authorization. Thus, a State would not
be authorized to implement these regulations as RCRA requirements until
State program modifications are submitted to EPA and approved, pursuant
to 40 CFR 271.21. Of course, States with existing regulations that are
more stringent than or broader in scope than current Federal
regulations may continue to administer and enforce their regulations as
a matter of State law. In implementing the HSWA requirements, EPA will
work with the States under agreements to avoid duplication of effort.
B. Effective Date
The effective date of today's rule is February 8, 1999, except as
specified in the Effective Dates section. As discussed above, since
today's rule is issued pursuant to HSWA authority, EPA will regulate
the management of the newly identified hazardous wastes until States
are authorized to regulate these wastes. Thus, EPA will apply Federal
regulations to these wastes and to their management in both authorized
and unauthorized States.
[[Page 42172]]
C. Section 3010 Notification
Pursuant to RCRA section 3010, the Administrator may require all
persons who handle hazardous wastes to notify EPA of their hazardous
waste management activities within 90 days after the wastes are
identified or listed as hazardous. This requirement may be applied even
to those generators, transporters, and treatment, storage, and disposal
facilities (TSDFs) that have previously notified EPA with respect to
the management of other hazardous wastes. The Agency has decided to
waive this notification requirement for persons who handle wastes that
are covered by today's listings and have already (1) notified EPA that
they manage other hazardous wastes, and (2) received an EPA
identification number. The Agency has waived the notification
requirement in this case because it believes that most, if not all,
persons who manage these wastes have already notified EPA and received
an EPA identification number. However, any person who generates,
transports, treats, stores, or disposes of these wastes and has not
previously received an EPA identification number must obtain an
identification number pursuant to 40 CFR 262.12 to generate, transport,
treat, store, or dispose of these hazardous wastes by November 4, 1998.
D. Generators and Transporters
Persons that generate newly identified hazardous wastes may be
required to obtain an EPA identification number if they do not already
have one (as discussed in section VI.C, above). In order to be able to
generate or transport these wastes after the effective date of this
rule, generators of the wastes listed today will be subject to the
generator requirements set forth in 40 CFR part 262. These requirements
include standards for hazardous waste determination (40 CFR 262.11),
compliance with the manifest (40 CFR 262.20 to 262.23), pretransport
procedures (40 CFR 262.30 to 262.34), generator accumulation (40 CFR
262.34), record keeping and reporting (40 CFR 262.40 to 262.44), and
import/export procedures (40 CFR 262.50 to 262.60). It should be noted
that the generator accumulation provisions of 40 CFR 262.34 allow
generators to accumulate hazardous wastes without obtaining interim
status or a permit only in units that are container storage units or
tank systems; the regulations also place a limit on the maximum amount
of time that wastes can be accumulated in these units. If these wastes
are managed in surface impoundments or other units that are not tank
systems or containers, these units are subject to the permitting
requirements of 40 CFR parts 264 and 265, and the generator is required
to obtain interim status and seek a permit (or modify interim status or
a permit, as appropriate). Also, persons who transport newly identified
hazardous wastes will be required to obtain an EPA identification
number as described above and will be subject to the transporter
requirements set forth in 40 CFR part 263.
E. Facilities Subject to Permitting
1. Facilities Newly Subject to RCRA Permit Requirements
Facilities that treat, store, or dispose of wastes that are subject
to RCRA regulation for the first time by this rule (that is, facilities
that have not previously received a permit pursuant to section 3005 of
RCRA and are not currently operating pursuant to interim status), might
be eligible for interim status (see section 3005(e)(1)(A)(ii) of RCRA).
In order to obtain interim status based on treatment, storage, or
disposal of such newly identified wastes, eligible facilities are
required to comply with 40 CFR 270.70(a) and 270.10(e) by providing
notice under section 3010 and submitting a Part A permit application no
later than February 8, 1999. Such facilities are subject to regulation
under 40 CFR part 265 until a permit is issued.
In addition, under section 3005(e)(3) and 40 CFR 270.73(d), not
later than February 8, 1999, land disposal facilities newly qualifying
for interim status under section 3005(e)(1)(A)(ii) also must submit a
Part B permit application and certify that the facility is in
compliance with all applicable groundwater monitoring and financial
responsibility requirements. If the facility fails to submit these
certifications and a permit application, interim status will terminate
on that date.
2. Existing Interim Status Facilities
Pursuant to 40 CFR 270.72(a)(1), all existing hazardous waste
management facilities (as defined in 40 CFR 270.2) that treat, store,
or dispose of the newly identified hazardous wastes and are currently
operating pursuant to interim status under section 3005(e) of RCRA,
must file an amended Part A permit application with EPA no later than
the effective date of today's rule, (i.e., February 8, 1999). By doing
this, the facility may continue managing the newly listed wastes. If
the facility fails to file an amended Part A application by that date,
the facility will not receive interim status for management of the
newly listed hazardous wastes and may not manage those wastes until the
facility receives either a permit or a change in interim status
allowing such activity (40 CFR 270.10(g)).
3. Permitted Facilities
Facilities that already have RCRA permits must request permit
modifications if they want to continue managing newly listed wastes
(see 40 CFR 270.42(g)). This provision States that a permittee may
continue managing the newly listed wastes by following certain
requirements, including submitting a Class 1 permit modification
request by the date on which the waste or unit becomes subject to the
new regulatory requirements (i.e., the effective date of today's rule),
complying with the applicable standards of 40 CFR parts 265 and 266 and
submitting a Class 2 or 3 permit modification request within 180 days
of the effective date.
Generally, a Class 2 modification is appropriate if the newly
listed wastes will be managed in existing permitted units or in newly
regulated tank or container units and will not require additional or
different management practices than those authorized in the permit. A
Class 2 modification requires the facility owner to provide public
notice of the modification request, a 60-day public comment period, and
an informal meeting between the owner and the public within the 60-day
period. The Class 2 process includes a ``default provision,'' which
provides that if the Agency does not reach a decision within 120 days,
the modification is automatically authorized for 180 days. If the
Agency does not reach a decision by the end of that period, the
modification is permanently authorized (see 40 CFR 270.42(b)).
A Class 3 modification is generally appropriate if management of
the newly listed wastes requires additional or different management
practices than those authorized in the permit or if newly regulated
land-based units are involved. The initial public notification and
public meeting requirements are the same as for Class 2 modifications.
However, after the end of the 60-day public comment period, the Agency
will grant or deny the permit modification request according to the
more extensive procedures of 40 CFR part 124. There is no default
provision for Class 3 modifications (see 40 CFR 270.42(c)).
Under 40 CFR 270.42(g)(1)(v), for newly regulated land disposal
units, permitted facilities must certify that the facility is in
compliance with all applicable 40 CFR part 265 groundwater monitoring
and financial responsibility requirements no later than February 8,
1999. If the facility fails to submit these
[[Page 42173]]
certifications, authority to manage the newly listed wastes under 40
CFR 270.42(g) will terminate on that date.
4. Units
Units in which newly identified hazardous wastes are generated or
managed will be subject to all applicable requirements of 40 CFR part
264 for permitted facilities or 40 CFR part 265 for interim status
facilities, unless the unit is excluded from such permitting by other
provisions, such as the wastewater treatment tank exclusions (40 CFR
264.1(g)(6) and 265.1(c)(10)) and the product storage tank exclusion
(40 CFR 261.4(c)). Examples of units to which these exclusions could
never apply include landfills, LTUs, waste piles, incinerators, and any
other miscellaneous units in which these wastes may be generated or
managed.
5. Closure
All units in which newly identified hazardous wastes are treated,
stored, or disposed after the effective date of this regulation that
are not excluded from the requirements of 40 CFR parts 264 and 265 are
subject to both the general closure and post-closure requirements of
Subpart G of 40 CFR parts 264 and 265 and the unit-specific closure
requirements set forth in the applicable unit technical standards
Subpart of 40 CFR parts 264 or 265 (e.g., Subpart N for landfill
units). In addition, EPA promulgated a final rule that allows, under
limited circumstances, regulated landfills, surface impoundments, or
LTUs to cease managing hazardous waste but to delay Subtitle C closure
to allow the unit to continue to manage non-hazardous waste for a
period of time prior to closure of the unit (see 54 FR 33376, August
14, 1989). Units for which closure is delayed continue to be subject to
all applicable 40 CFR parts 264 and 265 requirements. Dates and
procedures for submittal of necessary demonstrations, permit
applications, and revised applications are detailed in 40 CFR
264.113(c) through (e) and 265.113(c) through (e).
F. Landfill Leachate
Just weeks before the date for signature of this rule, one waste
management company raised to the Agency an issue not addressed in their
(or any other commenters'') public comments. The issue is that the
company claims to operate landfills in which some or all of the wastes
being listed today have already been disposed. These landfills generate
substantial volumes of leachate, which is collected and managed--mostly
by shipment via truck for treatment at Publicly Owned Treatment Works
(POTWs). On the date the listings take effect, the wastes become
hazardous, and a consequence is that this leachate would likewise be a
hazardous waste by virtue of the derived-from rule. See generally 53 FR
at 31147 (August 17, 1988); see also Chemical Waste Management v. EPA,
869 F. 2d 1526, 1536-37 (D.C. Cir. 1989) (sustaining this
interpretation). Although the landfills in which the wastes have been
previously disposed do not thereby become subject to Subtitle C
regulation, id., leachate which is collected and actively managed would
be regulated under Subtitle C. Id.
EPA's Office of Water recently proposed national effluent
limitations guidelines and pretreatment standards for wastewater
discharges (e.g., leachate) from certain types of landfills. 63 FR 6426
(February 6, 1998). In support of this proposal, EPA conducted a study
of the volume and chemical composition of wastewaters generated by both
Subtitle C and Subtitle D landfills. EPA did not propose pretreatment
standards for Subtitle D landfill wastewaters sent to POTWs because the
Agency's information indicated that such standards were not required
due to several factors, including (1) raw leachate data was below
published biological inhibition levels, and (2) lack of pass-through of
toxics (including lack of showing of adverse impact on POTW sludge
quality). 63 FR at 6444. EPA initially found, among other things, that
``the majority of pollutants typically found in raw [non-hazardous
landfill] leachate were at levels comparable to wastewater typically
found at the headworks of a POTW.'' Id.
Leachate from non-hazardous waste landfills that have historically
managed the newly-listed wastes would be leachate from a Subtitle D
facility, and so could ultimately be determined not to require
pretreatment under this pending proposal. However, if Subtitle C
regulation were to apply to leachate generated from such landfills,
leachate now trucked to POTWs would, as a practical matter, no longer
be managed by POTWs, since POTWs would not wish to become RCRA Subtitle
C facilities. Given the pending proposal that directly addresses the
treatment of landfill leachate under the Clean Water Act, EPA believes
it worthwhile to study whether RCRA regulation of such leachates may be
duplicative within the meaning of RCRA section 1006(b)(1) (which
requires EPA to integrate regulations under RCRA with other statutes
implemented by EPA in a manner that avoids duplication to the maximum
extent possible, consistent with the goals and policies of RCRA and the
other statutes).
Since this leachate issue was not brought to the Agency's attention
in a timely manner, EPA is taking no action on this issue in this
rulemaking. The final rule thus simply finalizes four of the proposed
listings (K169, K170, K171, and K172), therefore the possibility exists
that some leachate may be classified by one or more of these waste
codes (after the effective date of today's rule) for the reasons
outlined above. However, the Agency is seeking public comment on the
issue by means of a Notice of Data Availability (NODA), published
elsewhere in today's Federal Register. EPA plans to take some type of
action addressing this issue, after considering any public comments to
this projected NODA, before today's listings take effect. One of the
options the Agency might consider (after consideration of comments and
information in response to the NODA) would be temporarily deferring the
application of the listings to the leachate.
VIII. CERCLA Designation and Reportable Quantities
All hazardous wastes listed under RCRA and codified in 40 CFR
261.31 through 261.33, as well as any solid waste that is not excluded
from regulation as a hazardous waste under 40 CFR 261.4(b) and that
exhibits one or more of the characteristics of a RCRA hazardous waste
(as defined in Secs. 261.21 through 261.24), are hazardous substances
under CERCLA, as amended (see CERCLA section 101(14)(C)). CERCLA
hazardous substances are listed in Table 302.4 at 40 CFR 302.4 along
with their reportable quantities (RQs). If a hazardous substance is
released in an amount that equals or exceeds its RQ, the release must
be reported immediately to the National Response Center (NRC) pursuant
to CERCLA section 103.
A. Reporting Requirements
Under CERCLA section 103(a), the person in charge of a vessel or
facility from which a hazardous substance has been released in a
quantity that is equal to or exceeds its RQ must immediately notify the
NRC as soon as that person has knowledge of the release. The toll-free
telephone number of the NRC is 1-800-424-8802; in the Washington, DC,
metropolitan area, the number is (202) 267-2675. In addition to this
reporting requirement under CERCLA, section 304 of EPCRA requires
owners or operators of certain facilities to report releases of
extremely hazardous substances and CERCLA hazardous substances to State
[[Page 42174]]
and local authorities. EPCRA section 304 notification must be given
immediately after the release of an RQ or more to the community
emergency coordinator of the local emergency planning committee for any
area likely to be affected by the release and to the State emergency
response commission of any State likely to be affected by the release.
Under section 102(b) of CERCLA, all hazardous substances (as
defined by CERCLA section 101(14)) have a statutory RQ of one pound,
unless and until the RQ is adjusted by regulation. In today's final
rule, EPA is adding waste streams K169, K170, K171, and K172 to the
CERCLA list of hazardous substances and adjusting the one-pound
statutory RQs for these wastes.
B. Standard and Alternative RQ Adjustment Methodology
EPA's methodology for adjusting the RQs of individual hazardous
substances begins with an evaluation of the intrinsic physical,
chemical, and toxicological properties of each hazardous substance. The
intrinsic properties examined-called ``primary criteria''-are aquatic
toxicity, mammalian toxicity (oral, dermal, and inhalation),
ignitability, reactivity, chronic toxicity, and potential
carcinogenicity.
Generally, for each intrinsic property, EPA ranks the hazardous
substance on a five-tier scale, associating a specific range of values
on each scale with an RQ value of 1, 10, 100, 1,000, or 5,000 pounds.
Based on the various primary criteria, the hazardous substance may
receive several tentative RQ values. The lowest of the tentative RQs
becomes the ``primary criteria RQ'' for that substance.
After the primary criteria RQ is assigned, the substance is
evaluated further for its susceptibility to certain degradative
processes, which are used as secondary RQ adjustment criteria. These
natural degradative processes are biodegradation, hydrolysis, and
photolysis (BHP). If a hazardous substance, when released into the
environment, degrades relatively rapidly to a less hazardous form by
one or more of the BHP processes, its primary criteria RQ is generally
raised one level. Conversely, if a hazardous substance degrades to a
more hazardous product after its release, the original substance is
assigned an RQ equal to the RQ for the more hazardous substance, which
may be one or more levels lower than the RQ for the original substance.
The standard methodology used to adjust the RQs for RCRA hazardous
waste streams differs from the methodology applied to individual
hazardous substances. The procedure for assigning RQs to RCRA waste
streams is based on an analysis of the hazardous constituents of the
waste streams. The constituents of each RCRA hazardous waste stream are
identified in 40 CFR part 261, Appendix VII. EPA determines an RQ for
each constituent within the waste stream and establishes the lowest RQ
value of these constituents as the adjusted RQ for the waste stream. In
a November 20, 1995, proposed rule (60 FR 57747), EPA proposed one-
pound RQs for waste streams K169, K170, K171, and K172 based on this
standard methodology.
In the same rule, however, the Agency also proposed an alternative
method for adjusting the RQs of these four petroleum refining wastes.
The proposed alternative method involved developing ``concentration-
weighted'' RQs for the four wastes. Using this alternative method, EPA
first determined the maximum observed concentrations of each hazardous
constituent in the wastes. EPA then used these concentrations to
calculate the amount of each petroleum refining waste necessary to
contain the RQ of each constituent of concern.
Based on these calculated amounts, EPA assigned a ``concentration-
weighted'' RQ value of 1, 10, 100, 1,000, or 5,000 pounds to each waste
stream constituent. If the calculated amount for a particular
constituent was greater than the maximum RQ level of 5,000 pounds, the
``concentration-weighted'' constituent RQ would be 5,000 pounds. If the
calculated amount fell between two RQ levels, then the ``concentration-
weighted'' constituent RQ would be the lower of the two levels.
Finally, under this alternative method, the lowest of the
concentration-weighted constituent RQs would become the RQ for the
waste stream.
C. Basis for RQ Adjustments in Final Rule
In today's final rule, EPA has decided to use the standard RQ
adjustment methodology to assign RQs to petroleum refining wastes K169,
K170, K171, and K172. The Agency believes that introduction of a second
methodology (i.e., the alternative method described above), in addition
to the standard method already in use, may be difficult to implement
and may unnecessarily confuse the public and the regulated community.
EPA considered three specific implications of adopting the
alternative RQ adjustment methodology in making its determination to
retain the standard method. First, promulgation of RQs based on the
alternative methodology for the four petroleum refining wastes would
have introduced a potentially confusing situation in which RQs for
currently listed hazardous waste streams would be based on two
different methodologies. Second, since EPA's initial RQ adjustment
rulemakings were first published in 1983, EPA has consistently applied
the standard methodology to adjust the RQs for all previously listed
RCRA wastestream. Members of the public and the regulated community
understand and are complying with this methodology and related
reporting requirements. Third, the reduced reporting burden expected
from the application of the alternative method (i.e., reporting based
on constituent concentrations) to the four petroleum refining wastes
can be achieved by applying the mixture rule (as described in Section
VIII.D, ``Responses to Comments,'' of this preamble), without creating
a second, different RQ adjustment methodology.
Based on these considerations, the Agency has decided to use the
standard methodology, rather than the alternative method, to adjust the
RQs for the petroleum refining wastes in today's final rule. Using the
standard method, EPA today is assigning one-pound adjusted RQs (as
proposed) for waste streams K170, K171, and K172 based on the
constituent(s) within each of these newly listed waste streams with the
lowest RQ. The Agency, however, is modifying its interpretation of the
mixture rule (as described in detail in Section VIII.D below) to allow
facilities to use the maximum observed concentrations of the
constituents within the petroleum refining wastes in determining when
to report releases of these wastes.
In addition, EPA mentioned in the preamble to the November 20,
1995, proposed rule that the Agency was considering listing waste
stream K169 (crude oil storage tank sediment). Subsequent to the
proposal, EPA has decided to list K169 as a RCRA hazardous waste and a
CERCLA hazardous substance, and to adjust its RQ.
In the November 20, 1995 rule, EPA was considering a one-pound RQ
for K169 based on the one-pound RQs of three substances
(benzo(a)pyrene, dibenzo(a,h)anthracene, and benzo(b)fluoranthene)
originally identified by the Agency as constituents of this waste
stream. After further evaluation of the constituent data, however, the
Agency has decided in today's final rule to identify only one hazardous
constituent (i.e., benzene) for waste stream K169 in Appendix VII to
[[Page 42175]]
40 CFR part 261 (see Section V.B.2 for a discussion of the basis for
listing K169). Thus, using the standard RQ adjustment method, EPA is
promulgating a 10-pound RQ for K169 in today's final rule based on the
10-pound RQ of the waste's single hazardous constituent, benzene.
D. Response to Comments
As noted above, the Agency has decided to use the standard
methodology to adjust the RQs for K169, K170, K171, and K172. The
commenters on the proposed rule, however, favored the alternative RQ
adjustment methodology. These commenters suggested that reporting
should be based on actual concentration levels observed in each of the
petroleum refining wastes and that these levels are more likely to
warrant notification of government authorities.
In addition, one of the commenters asked EPA to clarify that a
waste generator could retain the option of applying the mixture rule to
releases of these petroleum refining wastes. Specifically, this would
allow the generator to report at a higher level if the generator knew
that the concentrations of the constituents in the waste were lower
than the maximum observed concentrations identified by EPA.
EPA acknowledges the commenters' support for less burdensome
reporting requirements and agrees with the commenters' assertion that
reporting for the four petroleum refining wastes should be based on
actual concentration levels observed in each of these wastes. The
Agency, however, believes that reductions in the reporting burden for
these four wastes can be achieved through the use of the mixture rule,
without creating a second, distinct RQ adjustment methodology. In
response to the commenters' concerns, the Agency is modifying its
interpretation of the mixture rule, as described below, to allow
facilities to use the maximum observed concentrations of the
constituents within K169, K170, K171, and K172 in determining when to
report releases of these wastes.
For K169, K170, K171, and K172, where the person in charge does not
know the actual concentrations of the hazardous constituents, that
person will have the option of reporting on the basis of the maximum
observed concentrations that have been identified by EPA (see Table
VIII-1 below). The change in EPA's interpretation of the mixture rule
that will allow use of these maximum concentrations is codified in 40
CFR 302.6(b)(1) as a new subparagraph (iii) in today's rule. Thus,
although the person in charge lacks actual knowledge of constituent
concentrations, constructive knowledge of the EPA-identified maximum
concentrations is assumed. This assumption is reasonable and
conservative because the sampling data presented in the Technical
Listing Document accurately identify the maximum observed
concentrations of the hazardous constituents in each of the petroleum
refining wastes. Table VIII-1 below identifies the hazardous
constituents for waste streams K169, K170, K171, and K172, their
maximum observed concentrations in ppm, their constituents' RQs as
listed in Table 302.4 of 40 CFR part 302, and the number of pounds of
the waste needed to contain an RQ of each constituent.
Table VIII-1.--Pounds Required to Contain RQ for Each Constituent
----------------------------------------------------------------------------------------------------------------
Pounds
Waste Constituent Max ppm RQ (lb) required to
contain RQ
----------------------------------------------------------------------------------------------------------------
K169 Benzene............................ 220 10 45,455
K170 Benzene............................ 1.2 10 8,333,333
Benzo (a) pyrene................... 230 1 4,348
Dibenz (a,h)anthracene............. 49 1 20,408
Benzo (a)anthracene................ 390 10 25,641
Benzo fluoranthene................. 110 1 9,090
Benzo (k) fluoranthene............. 110 5000 45,454,545
3-Methylcholanthrene............... 27 10 370,370
7,12-Dimethylbenz (a) anthracene... 1,200 1 833
K171 Benzene............................ 500 10 20,000
Arsenic............................ 1,600 1 625
K172 Benzene............................ 100 10 100,000
Arsenic............................ 730 1 1,370
----------------------------------------------------------------------------------------------------------------
For example, if waste stream K171 is released from a facility and
the person in charge does not know the actual concentrations of the
benzene and arsenic constituents, the person may assume that the
concentrations of benzene and arsenic are 500 and 1,600 ppm.
respectively. Thus, applying the mixture rule, 625 pounds of the K171
waste would need to be released (assuming the maximum concentrations
indicated in the table) to reach the RQ for arsenic in this waste.
Where the person in charge knows the concentration levels of all
the hazardous constituents in a particular petroleum refining waste,
the traditional mixture rule can be applied. Under this scenario,
reporting would be required only when an RQ or more of any hazardous
constituent is released. As applied to the petroleum refining wastes in
this rule, EPA's overall reporting approach reduces the burden of
notification requirements for the regulated community and adequately
protects public health and welfare and the environment. In addition,
EPA believes that the approach described above is consistent with the
view expressed by the commenters that reporting for the four wastes
should be based on actual concentration levels.
In the proposed rule preamble, EPA identified ``self-heating
solids'' as a hazardous constituent of waste streams K171 and K172. Two
of the commenters disagreed with the Agency's use of this term and
indicated that most K171 and K172 wastes do not demonstrate the RCRA
characteristic of ignitability. According to these commenters, the few
wastes that do exhibit this characteristic will already be subject to
the 100-pound RQ that applies to ignitable characteristic wastes.
Finally, the commenters stated that EPA's use of the term ``self-
heating solid'' as a constituent of K171 and K172 wastes would unfairly
lower the RQ for those wastes that do not possess the RCRA
characteristic of ignitability. EPA agrees with the commenters and has
removed the term ``self-heating solids'' from the
[[Page 42176]]
list of constituents of K171 and K172 in Table VIII-1 of today's final
rule.
IX. Executive Order 12866
Under Executive Order 12866, ``Regulatory Planning and Review'' (58
FR 51735, October 4, 1993), the Agency must determine whether the
regulatory action is ``significant'' and therefore subject to OMB
review and the requirements of the Executive Order. The Order defines
``significant regulatory action'' as one that is likely to result in a
rule that may:
(1) have an annual effect on the economy of $100 million or more
or adversely affects in a material way the economy, a sector of the
economy, productivity, competition, jobs, the environment, public
health or safety, or State, local, or tribal governments or
communities
(2) create a serious inconsistency or otherwise interferes with
an action taken or planned by another agency
(3) materially alter the budgetary impact of entitlements,
grants, user fees, or loan programs or the rights and obligations of
recipients thereof
(4) raise novel legal or policy issues arising out of legal
mandates, the President's priorities, or the principles set forth in
this Executive order.
Pursuant to the terms of Executive Order 12866, it has been
determined that this rule is a ``significant regulatory action''
because of policy issues arising out of legal mandates. As such, this
action was submitted to OMB for review. Changes made in response to OMB
suggestions or recommendations are documented in the public record.
X. Economic Analysis
Summary
This section of the preamble develops the costs and the industry
economic impact for the petroleum refining waste listings including
land disposal restriction (LDR) impacts. Based on this economic
analysis, the Agency estimates that the listing of the four refinery
wastes discussed above, including LDR impacts, the oil-bearing
hazardous secondary material exclusion (oil-bearing exclusion) and the
wastewaters from the headworks exemptions for crude oil storage tank
sediment (K169) and CSO sediment (K170), will result in nationwide
annualized compliance costs between $20 and $40 million, with an
expected value of about $30 million ($1997) 26 (see Table X-
2 below). Although Table X-2 shows a range from approximately $12
million to $60 million (columns 5 and 6), the likely range will be
narrower due to the available refinery choices and expected waste
volumes. The wide variance is nonetheless due to a high degree of
uncertainty in costing and, particularly, in volumes to be processed.
---------------------------------------------------------------------------
\26\ The range of cost estimates is explained in Document 5 of
the ``Background Documents for the Cost and Economic Impact Analysis
of Listing Four Petroleum Refining Wastes as Hazardous Under RCRA
Subtitle C,'' January 10, 1998.
---------------------------------------------------------------------------
Of special note is the relationship of previously listed petroleum
refinery wastes to this rulemaking. The ability to recycle wastes
through coker processing, as described herein, will enable refineries
to process previously listed wastes in a like manner. These wastes
include FO37, FO38, KO48, KO49 and KO51. A conservative estimate of the
volume of these wastes that may be processed, yielding oil that may be
converted to product, results in feedstock having a value of some $14
million to $28 million ($1997); see background document entitled
``Other Benefits From Recovery of Oil in Coker Processing Units'',
dated August 24, 1995. Clearly, the impact of this ``other'' benefit as
a potential offset to the costs of the rule described herein can be
substantial. If the volumes available from previously listed wastes are
higher than estimated, the value of oil generated may substantially
offset the costs of this rulemaking. It is important to note that EPA
has insufficient data to judge the extent to which the industry may
already be generating this added feedstock.
Industry pricing and operating impacts, developed using partial
equilibrium analysis, are expected to be minimal. This is due both to
the size of the industry and the latitude afforded industry in this
rulemaking. The full economic analysis is available in the regulatory
docket titled ``Background Documents for the Cost and Economic Impact
Analysis of Listing Four Petroleum Wastes as Hazardous Under RCRA
Subtitle C,'' January 10, 1998.
In the cited background document, supplemental cost impact analyses
accounting for the cost savings of the oil-bearing exclusion and the
headworks exemption are included, as well as impacts resulting from the
new Small Business Regulatory Enforcement Fairness Act of 1996 (SBREFA)
and the potential for unfunded mandates. Finally, as noted above, cost
savings from the recovery of oil in coker processing units are
evaluated for five previously listed petroleum refining industry wastes
but , also as noted, are not included as offsets to the costs estimated
for this rulemaking.
A. Compliance Costs for Listings Including LDR Impacts and the
Exclusion for Oil-Bearing Hazardous Secondary Materials
This Section describes (1) the universe of petroleum refineries and
volumes of petroleum refining wastes in the four waste groups listed,
including LDR impacts, (2) an overview of the industry impact
methodology, later described in detail, and detail of the methodology
for determining incremental compliance cost, (3) the potential remedial
action costs, and (4) a summary of incremental compliance cost results.
1. Universe of Petroleum Refineries and Waste Volumes
In order to estimate costs, it was first necessary to estimate
total annual generation of petroleum refining wastes. The domestic
petroleum refining industry affected by this ruling is composed of 162
refineries owned/operated by 80 companies. The quantity of waste at the
point of generation (i.e., entering the waste management system) could
range from 91,600 to 177,900 metric tons per year, with an expected
value of approximately 134,800 metric tons per year.27
---------------------------------------------------------------------------
\27\ Waste quantity estimates for the point of generation and
final management are presented in Table 3.3 of Document 1 of the
``Background Documents for the Cost and Economic Impact Analysis of
Listing Four Petroleum Refining Wastes as Hazardous Under RCRA
Subtitle C,'' January 10, 1998.
---------------------------------------------------------------------------
2. Methodology for Estimating Industry Economic Impact and Incremental
Compliance Cost
Industry Impact, Overview
Partial equilibrium analysis, as was noted, was used to evaluate
possible changes in market demand, estimate the post-control shift in
market supply, predict the change in market equilibrium (price and
quantity), and estimate plant closures. Petroleum refineries produce
several hundred products. The economic impact analysis evaluates the
impact of the listings based on ten petroleum products (i.e., ethane/
ethylene, butane/butylene, normal butane/butylene, isobutane/
isobutylene, finished motor gasoline, jet fuel, distillate and residual
fuel oil, asphalt, and petroleum coke), which represented 91 percent of
domestically refined petroleum products in 1992. Because compliance
costs for the hazardous waste listings cannot be allocated to any
specific products, output in the partial equilibrium model is defined
as a composite, bundled product equal to the sum of price
[[Page 42177]]
multiplied by the weighted production volumes of all ten products.
Due to the wide range of potential costs, as shown in the table at
the end of this section, a bounding analysis was conducted to evaluate
the maximum potential industry economic impact of this listing
determination. Highest cost options bounded the industry economic
impact analysis. The upper bound LDR Scenario assumes a pretreatment
management method of solidification prior to Subtitle C landfill for
metal-based wastes, combustion in a Subtitle C incinerator/BIF for
organic-based wastes, and a listing exemption granted for organic-based
wastes that are recycled to a coker. The lower bound LDR Scenario uses
the same assumptions except on-site incineration costs are assumed for
those refineries generating sufficient quantities to warrant
construction of an incinerator. EPA's judgement that industry impact is
minimal is based on upper-bound costs to the industry.
Incremental Compliance Cost
EPA's approach to the compliance cost analysis for this rule was to
compare the cost of current management practices, as reported in the
RCRA section 3007 Questionnaire of petroleum refineries, with the
projected cost of management to comply with the RCRA Subtitle C
hazardous waste program. This difference in cost, when annualized
28, represents the incremental annual compliance cost
attributable to the rule.
---------------------------------------------------------------------------
\28\ Costs are discounted at a rate of 7 percent over a 20-year
period.
---------------------------------------------------------------------------
Three scenarios are evaluated in this Cost and Economic Impact
Analysis. The first scenario, Listing Scenario, assesses the costs
incurred by the petroleum refining industry to comply with Subtitle C
regulation excluding LDR regulations. The Listing Scenario assumes an
end disposal management of Subtitle C landfilling or continued
combustion of wastes, where indicated as the baseline management
practice, in a Subtitle C incinerator/BIF.
The second scenario, LDR Scenario, expands on the Listing Scenario
by adding in cost impacts attributable to LDR regulations. Two options
are assessed for the LDR Scenario. In Option 1, the upper-bound
estimate, oil-based crude oil storage tank sediment (K169) and CSO
sediment (K170) are combusted in off-site Subtitle C incinerators and
spent hydrotreating and hydrorefining catalysts (K171, K172,
respectively) are combusted in off-site incinerators followed by
vitrification and Subtitle C landfill of the ash. In Option 2, the
lower-bound estimate, oil-based crude oil storage tank sediment (K169)
and CSO sediment (K170) are assumed to be managed in on-site Subtitle C
incinerators for those refineries generating sufficient quantities and
currently in the RCRA permitting program (thereby avoiding potential
corrective action costs). Spent hydrotreating and hydrorefining
catalysts (K171, K172) are assumed to be regenerated/reclaimed in RCRA-
exempt off-site metal recovery units.29 Compliance with LDR
requirements is presumed to be mandatory.
---------------------------------------------------------------------------
\29\ These cost estimates are presented in Document 1 of the
``Background Documents for the Cost and Economic Impact Analysis of
Listing Four Petroleum Refining Wastes as Hazardous Under RCRA
Subtitle C,'' January 10, 1998.
---------------------------------------------------------------------------
The third scenario, Oil-Bearing Exclusion Scenario, modifies the
Listing and LDR Scenarios by assuming the refinery will process crude
oil storage tank sediment (K169) and CSO sediment (K170) in coking
units where it is more cost-effective than Subtitle C management. Two
options are assessed for the Oil-Bearing Exclusion Scenario. In Option
1, the upper-bound estimate, crude oil storage tank sediment (K169) and
CSO sediment (K170) are processed in on-site and intracompany (i.e.,
``same company'') coking units when it is more economical than
management in off-site Subtitle C incinerators. In Option 2, the lower-
bound estimate, crude oil storage tank sediment (K169) and CSO sediment
(K170) are processed in intercompany (i.e., ``not same company'')
coking units when it is technically feasible and/or more economical
than management in off-site incinerators. ``Not same company'' costs
are lower because more companies will avail themselves of this option
if permitted to do so. Spent hydrotreating and hydrorefining catalysts
(K171, K172, respectively) are combusted in off-site incinerators
followed by vitrification and Subtitle C landfill of the
ash.30
---------------------------------------------------------------------------
\30\ These cost estimates are presented in Document 5 of the
``Background Documents for the Cost and Economic Impact Analysis of
Listing Four Petroleum Refining Wastes as Hazardous Under RCRA
Subtitle C,'' January 10, 1998.
---------------------------------------------------------------------------
Baseline or Current Management Scenario
Relying on 3007 Questionnaire responses and engineering site
visits, EPA was able to determine the current (i.e., 1992) management
practices for the handling and disposal of petroleum refining wastes.
Current management practices varied among facilities and waste streams,
and included such practices as on-/off-site Subtitle C/D landfill, off-
site Subtitle C incinerator/BIF, on-site surface impoundment,
recycling, recovery, regeneration, and reclamation. These ``current''
management practices at each facility represent the baseline scenario
of the analysis.
As part of the 3007 Questionnaire, EPA asked each facility to
identify current costs for the management of petroleum refining wastes.
For this analysis, EPA relied on and has not changed the industry's own
waste-specific estimates concerning the cost of current management.
Industry average unit costs were developed for each baseline management
practice from the 3007 Questionnaire data. EPA estimated costs for
baseline management practices when limited or no cost data were
provided in the 3007 Questionnaire. These calculated industry average
and estimated unit costs were used when a facility did not provide its
own unit cost estimates. EPA realizes that future events such as waste
minimization efforts or increased demand for refinery products may
change waste generation volumes and, thus, future waste management
costs.31 It is important to note that EPA also estimated
missing quantities to associate costs with these quantities.
---------------------------------------------------------------------------
\31\ Baseline unit cost estimates are presented in Tables 3.8
and 3.10 of Document 1 in the ``Background Documents for the Cost
and Economic Impact Analysis of Listing Four Petroleum Refining
Wastes as Hazardous Under RCRA Subtitle C,'' January 10, 1998.
---------------------------------------------------------------------------
Post-Regulatory Management Scenarios
In predicting how industry would comply with the listing of
petroleum refinery wastes as RCRA hazardous wastes, EPA developed the
three post-regulatory management scenarios, previously noted, that
represent reasonable management reactions on the part of industry.
Details of the compliance assumptions are presented by baseline
management practice in Table X-1. EPA developed these post-regulatory
management categories based on knowledge of current waste management
and the physical and chemical properties of the wastes. These scenarios
are further described as follows:
The ``Listing'' Scenario assumes an end disposal management
method of Subtitle C landfill or continued combustion of wastes,
where indicated as the baseline management practice, in a Subtitle C
incinerator/BIF. The use of the word ``Listing'' is intended to
emphasize that this scenario embodies only Subtitle C costs.
The LDR Scenario presents two options. In the first option, the
metal-based spent catalyst wastes are combusted in a Subtitle C
incineration followed by vitrification, and Subtitle C landfill of
the ash and the oil-based sediment wastes are combusted in off-
[[Page 42178]]
site Subtitle C incinerator/BIF units. This option reflects the
highest cost situation of all those examined. Other technologies may
be applicable (e.g., solvent extraction instead of incineration or
solidification instead of vitrification for metal-based wastes) to
meet LDR standards, but these are lower cost options and will not
provide an upper-bound to the cost and economic analysis. In the
second option, the spent hydrotreating and hydrorefining catalysts
(K171, K172, respectively) are reclaimed/recovered to take advantage
of the recycling exemption under RCRA Subtitle C regulation.
However, recordkeeping, storage, and transportation activities are
regulated under RCRA Subtitle C, while no LDR treatment costs are
included. The oil-based wastes are combusted in either an on- or
off-site Subtitle C incinerator/BIF depending on the economic
feasibility of constructing on-site incinerator units. If a facility
does not currently have a RCRA Part B permit, EPA assumed the
facility would choose not to construct an on-site incinerator in
order to avoid incurring potential costs under the RCRA corrective
action program.
The Oil-Bearing Exclusion Scenario also presents two options.
Because of the uncertainty regarding plant-specific coker capacity
availability, access limitations, cost limitations, feedstock
quality limitations, and State regulatory restrictions, the two
options given in Table X-2 were evaluated to bound the possible
results of the LDR scenarios with an oil-bearing exclusion. Refiners
will seek new cost optimization solutions since coking is now
economical when compared to Subtitle C management instead of
Subtitle D management. The first cost option considers that, when
economical, facilities will transport crude oil storage tank
sediment (K169) and CSO sediment (K170) to the nearest refinery
within the same company (i.e., intracompany) that currently operates
a coker. As a lower-bound cost option, it is assumed that technology
allowing insertion of de-oiled crude oil storage tank sediment
(K169) and CSO sediment (K170) into coker feedstocks will be
developed and intercompany transfers will occur, without the
transferring company paying the receiving company for the right to
avoid Subtitle C costs. However, it is not likely that there will be
no market pricing given potential profits (compared to Subtitle C
management costs) and potential benefits received by both the
generator and recycler; thus the lower bound.
Incremental compliance costs are determined for each management and
transportation practice by subtracting the baseline management cost
from the compliance management cost. For example, the incremental unit
compliance cost for wastes currently managed in off-site municipal
Subtitle D landfills that now will be managed in Subtitle C landfills
is $202/MT ($260/MT--$58/MT). This incremental unit cost is then
multiplied by the quantity of waste generated by the facility to
estimate the total incremental compliance cost. 32 Note that
from Table X-2 it is possible to select various mixes of compliance
options. For this rulemaking, EPA believes that the 2 right hand
columns bound the compliance costs. However, Option 1 (LDR Scenario)
was used in developing the worst case industry impact analysis.
---------------------------------------------------------------------------
\32\ Compliance unit cost estimates are presented in Table 3.9
and 3.10 of Document 1 in the ``Background Documents for the Cost
and Economic Impact Analysis of Listing Four Petroleum Refining
Wastes as Hazardous Under RCRA Subtitle C,'' January 10, 1998.
Table X-1.--Baseline vs. Compliance Practices
------------------------------------------------------------------------
Compliance
Baseline management practice Wastes managed assumptions
------------------------------------------------------------------------
Storage Methods:
Tank...................... K169--crude oil Upgrade to Subtitle C
storage tank accumulation tank
sediment K170-- system.a
CSO sediment
K171--spent
hydrotreating
catalyst K172--
spent
hydroreffining
catalyst.
Container (e.g., drum).... K169, K170, K171, Upgrade to Subtitle C
and K172. accumulation
container storage
area.(a)
Pile...................... K169, K170, and Construct new
K172. Subtitle C
accumulation tank
storage system.(b)
Roll-on/Roll-off Bin...... K169, K170, K171, Upgrade to Subtitle C
and K172. accumulation
container storage
area.(a)
Other..................... K169, K170, K171, Assume most common
and K172. storage type
reported by the
industry for that
waste type.
Treatment methods:
On-site Industrial Furnace K170............. In compliance. Add
RCRA Part 264 and
270 administrative
costs to permit
unit.
Other On-site Thermal K169............. On-site industrial
Treatment. furnace.
Off-site Incineration..... K169 and K171.... In compliance.
Construct a new on-
site Subtitle C
incinerator if more
economical than off-
site management.
Washing with Distillate... K169 and K170.... Upgrade to Subtitle C
accumulation tank
system. (a)
Washing with Water........ K169............. Upgrade to Subtitle C
accumulation tank
system.(a)
Other Cleaning/Extraction. K171 and K172.... Upgrade to Subtitle C
accumulation tank
system.(a)
Sludge Thickening......... K169 and K170.... Upgrade to Subtitle C
accumulation tank
system.(a)
Sludge De-watering........ K169 and K170.... Upgrade to Subtitle C
accumulation tank
system.(a)
Settling.................. K169 and K170.... Upgrade to Subtitle C
accumulation tank
system.(a)
Filtration................ K169 and K170.... Upgrade to Subtitle C
accumulation tank
system.(a)
Pressure Filtration/ K169 and K170.... Upgrade to Subtitle C
Centrifuging. accumulation tank
system for existing
units.(a) Construct
a new on-site
Subtitle C pressure
filtration/
centrifuge unit for
a waste minimization
opportunity for oily
sludges.(b)
Chemical Emulsion Break... K169............. Upgrade to Subtitle C
accumulation tank
system.(a)
Thermal Emulsion Break.... K169 and K170.... Upgrade to Subtitle C
accumulation tank
system.(a)
Other Phase Separation.... K169, K171, and Upgrade to Subtitle C
K172. accumulation tank
system.(a)
[[Page 42179]]
On-site Land treatment.... K169, K170, and Listing Scenario:
K171. Abandon on-site land
treatment unit and
dispose waste in off-
site Subtitle C
landfill.
LDR Scenario: K169/
K170--On-/Off-site
incineration;
K171--Option 1: Off-
site incineration
and ash
vitrification;
Option 2: Transfer
precious or non-
precious metal
catalysts for
reclamation or
regeneration.
Off-site Land treatment... K169 and K170.... Listing Scenario: Off-
site Subtitle C
landfill.
LDR Scenario: On-/Off-
site incineration.
Discharge to On-site WWT K169 and K170.... In compliance due to
Facility. the headwaters
exemption for
wastewaters
discharged to NPDES
or POTW.
Drying on a Pad........... K169 and K170.... Construct new
Subtitle C
accumulation tank
system. (b)
On-site Oxidation of K171 and K172.... Upgrade to Subtitle C
Pyrophoric Material. accumulation tank
system. (a)
On-site Stabilization..... K169, K170, K171, Upgrade to Subtitle C
and K172. accumulation tank
system. (a)
Off-site Stabilization.... K171............. Listing Scenario: In
compliance.
LDR Scenario: Ash
vitrification
following off-site
incineration.
Other Treatment........... K169............. Upgrade to Subtitle C
accumulation tank
system. (a)
Transfer Methods:
Transfer of Precious or K171 and K172.... Reclamation/
Nonprecious Metal regeneration
Catalysts for Reclamation/ facility will
Regeneration. increase Subtitle C
storage capacity and
upgrade to Subtitle
C transportation and
management.
Transfer to Non-Petroleum K169 and K170.... Off-site Subtitle C
Refinery for Direct Use BIF.
as a Fuel or to Make a
Fuel.
Transfer for Use as an K169............. Off-site Subtitle C
Ingredient in Products BIF.
that are Placed on the
Land.
Transfer to Other Off-site K169 and K171.... Assume most common
Entity. reported transfer
method reported by
industry for each
waste type.
Disposal methods:
NPDES..................... K169............. In compliance.
Off-site Municipal K169, K170, and Listing Scenario: Off-
Subtitle D Landfill. K171. site Subtitle C
landfill.
LDR Scenario: On-/Off-
site incineration.
Off-site Industrial K169, K170, K171, Listing Scenario: Off-
Subtitle D Landfill. and K172. site Subtitle C
Landfill.
LDR Scenario: On-/Off-
site incineration.
Off-site Subtitle C K169, K170, K171, Listing Scenario: In
Landfill. and K172. compliance.
LDR Scenario: K169/
K170--On-/Off-site
incineration;
K171/K172--Option 1:
Off-site
incineration
followed by ash
vitrification;
Option 2: Transfer
precious or
nonprecious metal
catalysts for
reclamation or
regeneration.
On-site Subtitle D K170, K171, and Listing Scenario: Off-
Landfill. K172. site Subtitle C
landfill.
LDR Scenario: K170--
On-/Off-site
incineration;
K171/K172--Option 1:
Off-site
incineration
followed by ash
vitrification;
Option 2: Transfer
precious or
nonprecious metal
catalysts for
reclamation or
regeneration.
On-site Subtitle C K169, K171, and Listing Scenario: In
Landfill. K172. compliance.
LDR Scenario: K169--
On-/Off-site
incineration;
K171/K172--Option 1:
Off-site
incineration
followed by ash
vitrification;
Option 2: Transfer
precious or
nonprecious metal
catalysts for
reclamation or
regeneration.
On-site Surface K169............. Dredge impoundment
Impoundment. sludge and dispose
in off-site Subtitle
D Landfill prior to
final listing and
then recommission
impoundment for non-
hazardous waste use;
Upgrade existing on-
site filtration
system to a Subtitle
C accumulation
system for sludge
management.(a)
Listing Scenario: Off-
site Subtitle C
landfill.
LDR Scenario: On-/Off-
site incineration.
------------------------------------------------------------------------
(a)Management costs (i.e., operation and maintenance costs) for
baseline and compliance are the same for this management method.
Secondary containment is included where appropriate.
(b) Management costs (i.e., O&M costs) for baseline and compliance are
the same for this management method. Secondary containment is included
where appropriate. The compliance cost will involve closure of the
drying pad and construction of a drying tank system with secondary
containment.
3. Potential Remedial Action Costs Within the Refining Industry
In addition to the refinery waste management costs themselves, the
petroleum refining hazardous waste listing could affect the management
of soils, leachates, groundwater, and remedial materials. The Agency's
``contained in'' policy defines certain remediation wastes
``containing'' a listed hazardous waste as a RCRA hazardous waste (see
Chemical Waste Management v. EPA, 869 F.2d 1526, D.C.C, 1989). Industry
sites where newly identified hazardous wastes have been managed prior
to the effective date of the new listings may still have contaminant
concentrations which exceed ``contained in'' levels. Any firm actively
managing such material could become a generator of RCRA hazardous
[[Page 42180]]
waste. Releases from all solid waste management units at these TSDFs,
including those that in the future would be found to contain a waste
meeting the petroleum listing descriptions, are covered by facility-
wide corrective action under 40 CFR 264.101. Associated costs, e.g.,
RCRA Facility Assessment, were addressed in the draft proposed
corrective action rule.
4. Summary of Compliance Cost Results
Table X-2 presents a summary of estimated incremental annualized
compliance costs for each waste due to (1) listing, (2) listing
including potential LDR pre-treatment regulations, and (3) listing
including LDR impacts and oil-bearing exclusion cost benefits.
Under the oil-bearing exclusion scenarios, the expected value
represents recycling of 65 percent of the oil-based crude oil storage
tank sediment (K169) and CSO sediment (K170) in either on-site coking
units or intracompany transfers when it is economically feasible, off-
site incineration of the remaining 35 percent of the oil-based crude
oil storage tank sediment (K169) and CSO sediment (K170) quantity, and
off-site incineration and vitrification of the spent hydrotreating and
hydrorefining catalysts. It is estimated that 65 percent of the oil-
based crude oil storage tank sediment (K169) and CSO sediment (K170)
quantity is recycled into coking units.
All of the above cost estimates, under each scenario, assume
implementation of waste minimization for filtering ``oily'' crude oil
storage tank sediment (K169) and CSO sediment (K170) and recycling the
oil filtrate back into process units. Revenues from the recycled oil
are roughly estimated at about $1 million per year but are not included
as an offset to costs in this table.
Table X-2.--Summary of Cost of Compliance
(1997 $millions per Year) 1,2
Oil-Bearing Exclusion Oil-Bearing Exclusion
Scenario Including Scenario Including
LDR Scenario Option LDR Impact Option 1-- LDR Impact Option 2--
1--Off-site LDR Scenario Option De-oil K169, K170, De-oil D169, K170,
Incineration of 2--On-/Off-site ``Not Same Company'' ``Same Company''
Waste stream Listing Scenario K169,K170 and Off-site Incineration of K169, Recycling to Coker, Recycling to Coker,
Incineration and K170 and Regeneration Off-site Incineration Off-site Incineration
Vitrification of K171, or Reclamation of of Remaining Sludge, of Remaining Sludge,
K172 K171, K172 3 and Regeneration or and Regeneration or
Reclamation of K171, Reclamation of K171,
K172 4 K172 4
Average Cost [Low- Average Cost [Low- Average Cost [Low- Average Cost [Low- Average Cost [Low-
High]. High]. High]. High]. High]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Crude Oil Storage Tank Sediment.... 2.5 [1.1-4.4]......... 24.1 [10.4-43.3]...... 18.6 [9.0-31.6]...... 8.7 [4.1-14.9]....... 13.0 [5.9-22.6].
Clarified Slurry Oil Sediment...... 3.1 [1.6-5.4]......... 25.1 [12.5-42.0]...... 18.8 [10.5-29.6]..... 8.1 [3.9-13.8]....... 13.5 [6.8-22.4].
Spent Hydrotreat- ing Catalyst..... 1.5 [0.9-3.2]......... 5.6 [3.9-8.5]......... 2.6 [1.3-5.0]........ 2.6 [1.3-5.0]........ 2.6 [1.3-5.0].
Spent Hydrorefining Catalyst....... 1.7 [0.8-4.2]......... 13.0 [9.3-18.4]....... 4.4 [2.1-8.8]........ 4.4 [2.1-8.8]........ 4.4 [2.1-8.8].
RCRA Administrative Costs.......... 0.6 [0.4-0.7]......... 0.6 [0.4-0.8]......... 0.9 [0.7-1.1]........ 0.6 [0.4-0.8]........ 0.6 [0.4-0.8].
Total........................ 9.4 [4.8-17.9]........ 68.4 [36.5-113.0]..... 45.3 [23.6-76.1]..... 24.4 [11.8-43.3]..... 34.1 [16.5-59.6].
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Cost uncertainty (Low-High) is estimated using a +/-50% adjustment of any estimated quantities and a +/-25% adjustment of any estimated costs.
Management practices and transportation unit costs were provided in the 1992 RCRA 3007 Questionnaire responses. If unit costs were not reported, an
industry-based average unit cost was used. If data were not available to derive an industry-based average, EPA estimated a unit cost for the
management practice based on previous listing determinations, land disposal restrictions analyses, and engineering cost documents. Compliance
management practice, transportation, and RCRA administrative unit costs, prices, and cost equations were obtained from industry-based averages derived
from the 1992 RCRA 3007 Questionnaire, previous listing determinations and land disposal restrictions analyses, and engineering cost documents.
2 In the analysis, 1992 costs were inflated to 1997 dollars using an inflation factor of 1.11657. The inflation factor is based on Engineering News-
Record construction (25% weighted) and common labor (75% weighted) cost indexes. The inflation factor is weighted towards labor factors because
compliance costs are more operational in function. Costs are annualized assuming a discounted rate of 7% over a 20-year period.
3 On-site incinerators are assumed only for those facilities that manage a large enough quantity of waste so that an on-site incinerator is more
economical for the facility and which are currently in the RCRA program. All other facilities are assumed to continue managing wastes off-site.
4 All crude oil storage tank sediment (K169) and CSO sediment (K170) wastes are assumed to be de-oiled in the cost estimate. The recovered oil is
recycled back into process units. For those refineries that reported oil recovery fractions, that data were used. For refineries that did not provide
data, using an industry average for crude oil storage tank sediment (K169) and CSO sediment (K170), 60 percent of the quantity entering the filtration
unit is assumed to be recovered as oil and the remaining 40 percent goes on for further management. Of the remaining de-oiled sediment quantity (i.e.,
40 percent fraction), 65 percent is assumed to be recycled into coking units. The remaining 35 percent is subject to Subtitle C management. If crude
oil storage tank sediment (K169) and CSO sediment (K170) are recycled into coking units, they are assumed to be subject to the oil-bearing exclusion.
Therefore, all storage, treatment, and transportation of these wastes are not subject to RCRA Subtitle C regulation. Option 1 reflects management of
crude oil storage tank sediment (K169) and CSO sediment (K170) in coking units owned by any company (i.e., ``not same company''). Option 2 reflects
management of crude oil storage tank sediment (K169) and CSO sediment (K170) in coking units as an option only within those companies that own them
(i.e., ``same company'').
B. Details of Industry Economic Impact
As noted, a partial equilibrium model was used to estimate primary
and secondary impacts from implementation of the listings. Primary
economic impacts include changes in market equilibrium price and output
levels, changes in the value of shipments or revenues to domestic
producers, and plant closures. Secondary impacts include changes in
employment, use of energy inputs, balance of trade, and regional
refinery distribution. Impacts associated with the two Oil-Bearing
Exclusion compliance scenarios will fall
[[Page 42181]]
between the range of primary and secondary economic impacts predicted
for the Listing and LDR compliance scenarios as shown in Table X-2 (the
low and high cost scenarios).
Predicted price increases and reductions in domestic output are
less than 1 percent for the ten products evaluated under both the
Listing and LDR compliance scenarios.33 The projected 1992
price increase for the ten products combined ranges from 0.03 to 0.76
percent under the low- and high-cost scenarios,
respectively.34 Under the low- and high-cost scenarios, 1992
production is expected to decrease, ranging from 1.3 to 30.9 million
barrels per year, representing a 0.02 to 0.59 percent decrease in
annual production, respectively. The value of shipments or revenues for
domestic producers are expected to increase for the ten products
combined, ranging from $9.0 to $213 million (1992 dollars) annually for
the low- and high-cost scenarios, respectively. This revenue increase
results given that the percent increase in price exceeds the percent
decrease in quantity for goods with inelastic demand. The model
estimates that up to two refineries may close as a result of the
predicted decrease in production under both regulatory scenarios. Those
refineries with the highest per unit control costs are assumed to be
marginal in the post-control market. No significant regional impacts
are anticipated from implementation of the listings since only up to
two facilities are anticipated to close and impacts overall are
estimated to be minimal. Primary economic impacts are not anticipated
to be significantly different in the later years of this decade and
even beyond (even though 1992 data were used herein) in that the
industry is mature and not one that changes often or dramatically
absent an external shock.
---------------------------------------------------------------------------
\33\ The ten petroleum products include ethane/ethylene, butane/
butylene, normal butane/butylene, isobutane/isobutylene, finished
motor gasoline, jet fuel, distillate and residual fuel oil, asphalt,
and petroleum coke.
\34\ Similar percentage increases would apply to current prices.
---------------------------------------------------------------------------
Under the low- and high-cost scenarios, the number of workers
employed in 1992 by firms in SIC 2911 are estimated to decrease ranging
from 12 to 282 workers annually, representing a 0.03 and 0.59 percent
decrease in total employment, respectively. The small magnitude of
predicted job loss directly results from the relatively small decrease
in production anticipated and the relatively low labor intensity in the
industry. An estimated decrease in energy use ranging from $1.02 to
$24.32 million ($1992) per year is expected for the industry, under the
low- and high-cost scenarios, respectively. As production decreases,
the amount of energy input utilized by the refining industry also
declines. The change in energy use does not consider the increased
energy use associated with operating and maintaining the regulatory
control equipment due to the lack of available data. Finally,
imposition of the listings will further increase the negative balance
of trade. Under the low- and high-cost scenarios, net exports are
anticipated to decline ranging from 0.2 to 4.7 million barrels per
year, representing a 0.1 and 2.8 percent decline, respectively. The
dollar value of the total decline in net exports ranges from $6.35 to
$152.6 million ($1992) per year. Given the magnitude of the estimated
compliance costs, refineries are expected to incur minimal economic
impacts. Secondary economic impacts are not anticipated to be
significantly different in 1997.
Economic impacts may be slightly underestimated as a result of the
following model input changes:
The economic analysis was based on a lower CSO sediment quantity
estimate of 9,000 MT/yr managed in final management practices. This
quantity was revised to 13,100 MT/yr. As a result, impacts for
facilities generating this sediment are underestimated for all
scenarios.
The regulatory options (i.e., waste management options) used to
evaluate economic impacts differ slightly from those that were used
to calculate the cost of compliance for the lower- and upper-bound
LDR Scenarios, such that waste management costs were understated by
$3 and $31 million ($1992), respectively. As a result, economic
impacts may be understated for the lower-and upper-bound LDR
Scenarios. However, the Oil-Bearing Exclusion Scenario, with
estimated costs from $31 to $67 million ($1992) and an expected
value of $45 million, fall within the range of costs used in the
economic impact analysis for the LDR Scenarios. Therefore, the
lower-and upper-bound LDR Scenarios bound the anticipated cost of
the rule (i.e., the Oil-Bearing Exclusion Scenario).
Economic impacts may be overestimated as a result of the following
model assumptions:
The model assumes that all refineries compete in a national
market. In reality, some refineries are protected from market
fluctuations by regional or local trade barriers and may therefore
be less likely to feel impact.
The total cost of compliance is assigned exclusively to ten
petroleum products, rather than the entire product slate for each
refinery.
Some refineries may find it profitable to expand production in
the post-control market. This would occur when a firm found its
post-control incremental unit cost to be smaller than the post-
control market price. Expansion by these firms would result in a
smaller decrease in output and increase in price than otherwise
would occur.
The economic analysis was initially based on the listing of five
waste streams including unleaded gasoline sediment, which has since
been removed from the list of wastes included in this listing
determination. As a result, economic impacts for the 98 facilities
generating unleaded gasoline sediment will be overestimated.
With the combined effects of analyzing five waste streams and
using a lower CSO sediment quantity and a less costly upper-bound
LDR Scenario management option, the total cost of compliance for the
Listing Scenario is understated by $2 million and the lower-bound
and upper-bound LDR Scenarios are understated by $5 million and $31
million ($1992), respectively. As a result, economic impacts may be
understated for the Listing and LDR Scenarios. However, as noted,
economic impacts estimated for the Listing and LDR scenarios bound
the anticipated economic impacts associated with the Oil-Bearing
Exclusion Scenario.
Under any realistic set of assumptions associated with this
listing, industry economic impact is likely to be very slight. The
results of the economic impact analysis are summarized in Table X-3.
Table X-3.--Summary of Economic Impacts \1\, \2\
------------------------------------------------------------------------
Listing LDR LDR
Economic impacts scenario scenario scenario
lower-bound lower-bound upper-bound
------------------------------------------------------------------------
Primary Economic Impacts
------------------------------------------------------------------------
Average Price Increase:
Over All Products............ 0.03% 0.08% 0.76%
[[Page 42182]]
Annual Production Decrease:
Amount (MMbbl)............... (1.3) (3.27) (30.93)
Percentage Change............ (0.03%) (0.06%) (0.59%)
Annual Value of Shipments
Amount (MM$92)............... $9.0 $22.59 $213.34
Percentage Change............ 0.01% 00.02% 0.16%
Number of Plant Closures......... 0-2 0-2 0-2
------------------------------------------------------------------------
Secondary Economic Impacts
------------------------------------------------------------------------
Annual Job Loss:.................
Number....................... (12) (30) (282)
Percentage Change............ (0.03%) (0.06%) (0.59%)
Annual Decrease In Energy Use:
Amount (MM$92)............... ($1.02) ($2.57) ($24.32)
Percentage Change............ (0.03%) (0.06%) (0.59%)
Annual Net Foreign Trade Loss:
Amount (MMbbl)............... (0.20) (0.49) (4.70)
Percentage Change............ (0.12%) (0.3%) (2.8%)
Dollar Value ($/MMbbl)....... ($6.35) ($15.96) ($152.60)
------------------------------------------------------------------------
\1\ Assumes listing of five waste streams: crude oil storage tank
sediment, clarified slurry oil sediment, unleaded tank sediment, spent
hydrotreating catalyst, and spent hydrorefining catalyst. Unleaded
tank sediment was not listed. Impact will be reduced with four.
\2\ The analysis was conducted using 1992 cost and price data. Costs and
prices were not inflated to 1997 dollars and the economic impact
analysis was not revised because the economic impacts are not
anticipated to change significantly. Anticipated costs with the
granting of a oil-bearing exclusion fall within the range used in the
economic impact analysis.
XI. Regulatory Flexibility Act
The Regulatory Flexibility Act (RFA) of 1980 as amended by SBREFA
requires Federal agencies to consider ``small entities'' throughout the
regulatory process. EPA policy suggests that an initial screening
analysis be performed to determine whether small entities will be
affected by the regulation. If affected small entities are identified,
regulatory alternatives should be considered which mitigate the
potential impacts. Small entities as described in the Act are only
those ``businesses, organizations and governmental jurisdictions
subject to regulation.'' In addition, the Agency must prepare an IRFA,
unless the head of the Agency certifies that the rule will not have a
significant impact on a substantial number of small entities.
The Small Business Administration (SBA) size standards criteria
apply to firm size, whereas the economic impact analysis for this
rulemaking was conducted at the facility level (i.e., refinery level).
Few companies employ more than 1,500 employees, and data on the number
of employees at company level were much less readily available than
were capacity data. For single-plant firms, the SBA criteria were
applied directly. For firms (i.e., companies) owning more than one
refinery, crude capacity was aggregated for all plants (i.e.,
refineries) to determine the overall size of the company.35
Despite the high percentage of small entities in the population of
refinery companies affected by the listing determination, anticipated
impacts as a result of implementation of the listings were minimal,
with a maximum of two plant closures predicted under the most
conservative assumptions used in each of the scenarios evaluated.
---------------------------------------------------------------------------
\35\ According to ``EPA Guidelines for Implementing the
Regulatory Flexibility Act'' (February, 1997) and the Small Business
Size Regulations (13 CFR 121), any refinery that produces petroleum
products (SIC 2911) of less than or equal to 75,000 barrels of crude
per day and has no more than 1,500 employees, constitutes a ``small
entity.'' The Agency believes that none of the entities which would
incur incremental compliance costs as a result of this rulemaking
produce more than 75,000 barrels and have less than 1,500 employees.
---------------------------------------------------------------------------
Of the 66 affected companies, 32 entities fit the definition of a
small entity as defined by the RFA. Table XI-1 presents the estimated
annualized incremental compliance costs borne by the 32 small
businesses in the petroleum refining industry. The annual incremental
cost of the rule for the 32 facilities ranged from $4,566 to $11.8
million (1992 dollars). For each of the 32 facilities impacted, these
annual costs constitute less than 0.96 percent of total annual sales.
EPA believes that these costs do not represent a significant impact.
Hence, pursuant to section 605(b) of the RFA, 5 U.S.C. 605(b), the
Administrator certifies that this rule will not have a significant
economic impact on a substantial number of small entities.
XII. Submission to Congress and the General Accounting Office
The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the
Small Business Regulatory Enforcement Fairness Act of 1996, generally
provides that before a rule may take effect, the agency promulgating
the rule must submit a rule report, which includes a copy of the rule,
to each House of the Congress and to the Comptroller General of the
United States. EPA will submit a report containing this rule and other
required information to the U.S. Senate, the U.S. House of
Representatives, and the Comptroller General of the United States prior
to publication of the rule in the Federal Register. This action is not
a ``major rule'' as defined by 5 U.S.C. Sec. 804(2). This rule will be
effective six months from the date of publication.
[[Page 42183]]
Table XI-1.--Results of the Regulatory Flexibility Analysis (a)
----------------------------------------------------------------------------------------------------------------
Summary of economic impacts on small entities
-----------------------------------------------------------------------------------------------------------------
LDR scenario lower LDR scenario upper-
Listing scenarios bound bound
----------------------------------------------------------------------------------------------------------------
Range of Annualized Compliance Costs.......... $4,566-$305,379 $4,556-$7,561,781 $4,556-$11,765,904
Range of Annual Company Refinery Sales........
(2) $19,377,340-$1,218,936,710
Range of Annualized Compliance Costs as a
Percentage of Company Refinery Sales......... 0.001%-0.236% 0.001%-0.620% 0.001%-0.965%
----------------------------------------------------------------------------------------------------------------
(a) The analysis was conducted using 1992 cost and price data. Costs and prices were not inflated to 1997
dollars and the analysis was not revised because the anticipated impacts would still be insignificant.
XIII. Unfunded Mandates
Under section 202 of the Unfunded Mandates Reform Act of 1995
(``UMRA'') signed into law on March 22, 1995, The EPA must prepare a
statement to accompany any rule where the estimated costs to State,
local, or tribal governments, or to the private sector, will be $100
million or more in any one year. Section 203 requires the epa to
establish a plan for informing and advising any small governments that
may be significantly or uniquely impacted by the rule.
Under section 205, agencies also must develop a process to permit
elected State, local, and tribal government officials to provide
``meaningful and timely input'' into the development of regulatory
proposals ``containing significant intergovernmental mandates.'' In
addition, agencies must consider a ``reasonable number of regulatory
alternatives'' and select the least costly, most cost-effective, or
least burdensome alternative that achieves the objectives of the rule,
unless the provisions of the alternative are inconsistent with the law
or an explanation is provided by the head of the affected agency.
EPA has determined that this rule does not include a Federal
mandate that may result in estimated costs of $100 million or more to
either State, local, or tribal governments in the aggregate or to the
private sector. The rule would not impose any Federal intergovernmental
mandate because it imposes no enforceable duty upon State, tribal, or
local governments. States, tribes, and local governments would have no
compliance costs under this rule, which applies only to facilities
managing the listed petroleum production wastes. It is expected that
States will adopt similar rules and submit those rules for inclusion in
their authorized RCRA programs, but they have no legally enforceable
duty to do so. For the same reasons, EPA also has determined that this
rule contains no regulatory requirements that might significantly or
uniquely affect small governments.
In addition, as discussed above, the private sector is not expected
to incur costs exceeding $100 million in any one year. The upper-bound
of the range of potential average annual costs is estimated to be $60
million ($1997) with the granting of an oil-bearing exclusion,
considerably below the $100 million annual threshold. The Agency
believes that this average annual cost represents the typical cost for
any given year and that this rulemaking will not result in a spike in
annual cost that might rise above $100 million in any given year above
for the following reasons. First, compliance with these new
requirements does not involve significant capital costs which could
generate such a spike. Treatment and disposal capacity for these wastes
already exist and the typical costs incurred come from treatment and
disposal on a routine basis. Second, waste generation rates for these
wastes are expected to be relatively constant over time. No signficant
surge in generation of the wastes listed in this rule involving a
concomitant increase in costs are anticipated.
XIV. Paperwork Reduction Act
This rule does not contain any new information collection
requirements subject to OMB review under the Paperwork Reduction Act of
1995, 44 U.S.C. 3501 et seq. Facilities will have to comply with the
existing Subtitle C recordkeeping and reporting requirements for the
newly listed waste streams.
To the extent that this rule imposes any information collection
requirements under existing RCRA regulations promulgated in previous
rulemakings, those requirements have been approved by the Office of
Management and Budget (OMB) under the Paperwork Reduction Act, 44
U.S.C. 3501 et seq., and have been assigned OMB control numbers 2050-
0009 (ICR no. 1573, Part B Permit Application, Permit Modifications,
and Special Permits); 2050-0120 (ICR 1571, General Facility Hazardous
Waste Standards); 2050-0028 (ICR 261, Notification of Hazardous Waste
Activity); 2050-0034 (ICR 262, RCRA Hazardous Waste Permit Application
and Modification, Part A); 2050-0039 (ICR 801, Requirements for
Generators, Transporters, and Waste Management Facilities under the
Hazardous Waste Manifest System); 2050-0035 (ICR 820, Hazardous Waste
Generator Standards); and 2050-0024 (ICR 976, 1997 Hazardous Waste
Report.
Release reporting required as a result of listing wastes as
hazardous substances under CERCLA and adjusting the RQs has been
approved under the provisions of the Paperwork Reduction Act, 44 U.S.C.
3501 et seq., and has been assigned OMB control number 2050-0046 (ICR
1049, Notification of Episodic Release of Oil and Hazardous
Substances).
XV. National Technology Transfer and Advancement Act
Under Section 12(d) of the National Technology Transfer and
Advancement Act, the Agency is directed to use voluntary consensus
standards in its regulatory activities unless to do so would be
inconsistent with applicable law or otherwise impractical. Voluntary
consensus standards are technical standards (e.g., materials
specifications, test methods, sampling procedures, business practices,
etc.) that are developed or adopted by voluntary consensus standard
bodies. Where available and potentially applicable voluntary consensus
standards are not used by EPA, the Act requires the Agency to provide
Congress, through the OMB, an explanation of the reasons for not using
such standards.
This rule does not establish any new technical standards and thus,
the Agency has no need to consider the use of voluntary consensus
standards in developing this final rule.
XVI. Executive Order 13045--Protection of Children From
Environmental Health Risks and Safety Risks
The Executive Order 13045 is entitled ``Protection of Children from
[[Page 42184]]
Environmental Health Risks and safety Risks (62 FR 19885, April 23,
1997). This Order applies to any rule that EPA determines (1) is
``economically significant'' as defined under Executive Order 12866,
and (2) the environmental health or safety risk addressed by the rule
has a disproportionate effect on children. If the regulatory action
meets both criteria, the Agency must evaluate the environmental health
or safety effects of the planned rule on children, and explain why the
planned regulation is preferable to other potentially effective and
reasonably feasible alternatives considered by the Agency
This final rule is not subject to E.O. 13045 because this is not an
economically significant regulatory action as defined by E.O. 12866.
List of Subjects
40 CFR Part 148
Administrative practice and procedure, Hazardous waste, Reporting
and recordkeeping requirements, Water supply.
40 CFR Part 261
Environmental protection, Hazardous waste, Recycling, Reporting and
recordkeeping requirements.
40 CFR Part 266
Environmental protection, Boilers and industrial furnaces, Energy,
Hazardous waste, Recycling, Reporting and recordkeeping requirements.
40 CFR Part 268
Environmental protection, Hazardous waste, Reporting and
recordkeeping requirements.
40 CFR Part 271
Environmental protection, Administrative practice and procedure,
Confidential business information, Hazardous materials transportation,
Hazardous waste, Indians-lands, Intergovernmental relations, Penalties,
Reporting and recordkeeping requirements, Water pollution control,
Water supply.
40 CFR Part 302
Environmental protection, Air pollution control, Chemicals,
Hazardous substances, Hazardous waste, Intergovernmental relations,
Natural resources, Reporting and recordkeeping requirements, Superfund,
Water pollution control, Water supply.
Dated: June 29, 1998.
Carol M. Browner,
Administrator.
For the reasons set out in the preamble, title 40, chapter I, of
the Code of Federal Regulations is amended as follows:
PART 148--HAZARDOUS WASTE INJECTION RESTRICTIONS
1. The authority citation for part 148 continues to read as
follows:
Authority: Secs. 3004, Resource Conservation and Recovery Act,
42 U.S.C. 6901 et seq.
2. Section 148.18 is amended by adding paragraph (i) to read as
follows:
Sec. 148.18 Waste specific prohibitions--newly listed and identified
Wastes.
* * * * *
(i) Effective February 8, 1999, the wastes specified in 40 CFR
261.32 as EPA Hazardous Waste Numbers K169, K170, K171, and K172 are
prohibited from underground injection.
PART 261--IDENTIFICATION AND LISTING OF HAZARDOUS WASTE
3. The authority citation for part 261 continues to read as
follows:
Authority: 42 U.S.C. 6905, 6912(a), 6921, 6922, 6924(y), and
6938.
4. Section 261.3 is amended by revising paragraphs (a)(2)(iv)(C)
and (c)(2)(ii)(B); and by adding paragraph (c)(2)(ii)(E) to read as
follows.
Sec. 261.3 Definition of hazardous waste.
(a) * * *
(2) * * *
(iv) * * *
(C) One of the following wastes listed in Sec. 261.32, provided
that the wastes are discharged to the refinery oil recovery sewer
before primary oil/water/solids separation--heat exchanger bundle
cleaning sludge from the petroleum refining industry (EPA Hazardous
Waste No. K050), crude oil storage tank sediment from petroleum
refining operations (EPA Hazardous Waste No. K169), clarified slurry
oil tank sediment and/or in-line filter/separation solids from
petroleum refining operations (EPA Hazardous Waste No. K170), spent
hydrotreating catalyst (EPA Hazardous Waste No. K171), and spent
hydrorefining catalyst (EPA Hazardous Waste No. K172); or
* * * * *
(c) * * *
(2) * * *
(ii) * * *
(B) Waste from burning any of the materials exempted from
regulation by Sec. 261.6(a)(3)(iii) and (iv).
* * * * *
(E) Catalyst inert support media separated from one of the
following wastes listed in Sec. 261.32--Spent hydrotreating catalyst
(EPA Hazardous Waste No. K171), and Spent hydrorefining catalyst (EPA
Hazardous Waste No. K172).
* * * * *
5. In Sec. 261.4, new paragraphs (a)(18) and (a)(19) are added, and
paragraph (a)(12) is revised to read as follows:
* * * * *
Sec. 261.4 Exclusions.
(a) * * *
(12) (i) Oil-bearing hazardous secondary materials (i.e., sludges,
byproducts, or spent materials) that are generated at a petroleum
refinery (SIC code 2911) and are inserted into the petroleum refining
process (SIC code 2911--including, but not limited to, distillation,
catalytic cracking, fractionation, or thermal cracking units (i.e.,
cokers)) unless the material is placed on the land, or speculatively
accumulated before being so recycled. Materials inserted into thermal
cracking units are excluded under this paragraph, provided that the
coke product also does not exhibit a characteristic of hazardous waste.
Oil-bearing hazardous secondary materials may be inserted into the same
petroleum refinery where they are generated, or sent directly to
another petroleum refinery, and still be excluded under this provision.
Except as provided in paragraph (a)(12)(ii) of this section, oil-
bearing hazardous secondary materials generated elsewhere in the
petroleum industry (i.e., from sources other than petroleum refineries)
are not excluded under this section. Residuals generated from
processing or recycling materials excluded under this paragraph
(a)(12)(i), where such materials as generated would have otherwise met
a listing under subpart D of this part, are designated as F037 listed
wastes when disposed of or intended for disposal.
(ii) Recovered oil that is recycled in the same manner and with the
same conditions as described in paragraph (a)(12)(i) of this section.
Recovered oil is oil that has been reclaimed from secondary materials
(including wastewater) generated from normal petroleum industry
practices, including refining, exploration and production, bulk
storage, and transportation incident thereto (SIC codes 1311, 1321,
1381, 1382, 1389, 2911, 4612, 4613, 4922, 4923, 4789, 5171, and 5172.)
Recovered oil does not include oil-bearing hazardous wastes listed in
subpart D of this part; however, oil recovered from such wastes may be
considered recovered oil. Recovered oil does not include used oil as
defined in 40 CFR 279.1.
* * * * *
[[Page 42185]]
(18) Petrochemical recovered oil from an associated organic
chemical manufacturing facility, where the oil is to be inserted into
the petroleum refining process (SIC code 2911) along with normal
petroleum refinery process streams, provided:
(i) The oil is hazardous only because it exhibits the
characteristic of ignitability (as defined in Sec. 261.21) and/or
toxicity for benzene (Sec. 261.24, waste code D018); and
(ii) The oil generated by the organic chemical manufacturing
facility is not placed on the land, or speculatively accumulated before
being recycled into the petroleum refining process. An ``associated
organic chemical manufacturing facility'' is a facility where the
primary SIC code is 2869, but where operations may also include SIC
codes 2821, 2822, and 2865; and is physically co-located with a
petroleum refinery; and where the petroleum refinery to which the oil
being recycled is returned also provides hydrocarbon feedstocks to the
organic chemical manufacturing facility. ``Petrochemical recovered
oil'' is oil that has been reclaimed from secondary materials (i.e.,
sludges, byproducts, or spent materials, including wastewater) from
normal organic chemical manufacturing operations, as well as oil
recovered from organic chemical manufacturing processes.
(19) Spent caustic solutions from petroleum refining liquid
treating processes used as a feedstock to produce cresylic or
naphthenic acid unless the material is placed on the land, or
accumulated speculatively as defined in Sec. 261.1(c).
* * * * *
Sec. 261.6 [Amended]
6. In Sec. 261.6, paragraph (a)(3)(iv)(C) is amended by removing
``; and'' at the end of the paragraph and adding a period in its place;
and paragraph (a)(3)(v) is removed.
7. In Sec. 261.31(a), the table is amended by revising the entry
for F037, to read as follows:
Sec. 261.31 Hazardous wastes from non-specific sources.
(a) * * *
------------------------------------------------------------------------
Industry and EPA
hazardous waste No. Hazardous waste Hazard code
------------------------------------------------------------------------
* * * *
F037................ Petroleum refinery primary oil/ (T)
water/solids separation sludge-
Any sludge generated from the
gravitational separation of oil/
water/solids during the storage
or treatment of process
wastewaters and oily cooling
wastewaters from petroleum
refineries. Such sludges
include, but are not limited to,
those generated in oil/water/
solids separators; tanks and
impoundments; ditches and other
conveyances; sumps; and
stormwater units receiving dry
weather flow, sludge generated
in stormwater units that do not
receive dry weather flow,
sludges generated from non-
contact once-through cooling
waters segregated for treatment
from other process or oily
cooling waters, sludges
generated in aggressive
biological treatment units as
defined in Sec. 261.31(b)(2)
(including sludges generated in
one or more additional units
after wastewaters have been
treated in aggressive biological
treatment units) and K051 wastes
are not included in this
listing. This listing does
include residuals generated from
processing or recycling oil-
bearing hazardous secondary
materials excluded under Sec.
261.4(a)(12)(i), if those
residuals are to be disposed of.
* * * *
* * *
------------------------------------------------------------------------
* * * * * * *
8. In Sec. 261.32, the table is amended by adding in alphanumeric
order (by the first column) the following waste streams to the subgroup
``Petroleum refining'' to read as follows:
Sec. 261.32 Hazardous wastes from specific sources.
* * * * * * *
------------------------------------------------------------------------
Industry and EPA
hazardous waste No. Hazardous waste Hazard code
------------------------------------------------------------------------
* * * *
Petroleum refining:
* * * *
* * *
K169.............. Crude oil storage tank sediment (T)
from petroleum refining
operations.
K170.............. Clarified slurry oil tank (T)
sediment and/or in-line filter/
separation solids from petroleum
refining operations.
K171.............. Spent Hydrotreating catalyst from (I,T)
petroleum refining operations,
including guard beds used to
desulfurize feeds to other
catalytic reactors (this listing
does not include inert support
media).
K172.............. Spent Hydrorefining catalyst from (I,T)
petroleum refining operations,
including guard beds used to
desulfurize feeds to other
catalytic reactors (this listing
does not include inert support
media).
* * * *
* * *
------------------------------------------------------------------------
9. Appendix VII to Part 261 is amended by adding the following
waste streams in alphanumeric order (by the first column) to read as
follows.
[[Page 42186]]
APPENDIX VII TO PART 261--BASIS FOR LISTING HAZARDOUS WASTE
------------------------------------------------------------------------
EPA hazardous waste No. Hazardous constituents for which listed
------------------------------------------------------------------------
* * * *
K169........................ Benzene.
K170........................ Benzo(a)pyrene, dibenz(a,h)anthracene,
benzo (a) anthracene, benzo
(b)fluoranthene, benzo(k)fluoranthene, 3-
methylcholanthrene, 7, 12-
dimethylbenz(a)anthracene.
K171........................ Benzene, arsenic.
K172........................ Benzene, arsenic.
------------------------------------------------------------------------
PART 266--STANDARDS FOR THE MANAGEMENT OF SPECIFIC HAZARDOUS WASTES
AND SPECIFIC TYPES OF HAZARDOUS WASTE MANAGEMENT FACILITIES
The authority citation for part 266 is revised to read as follows:
Authority: 42 U.S.C. 1006, 2002(a), 3004, and 3014, 6905, 6906,
6912, 6922, 6924, 6925, and 6937.
11. Section 266.100(b)(3) is revised to read as follows:
Sec. 266.100 Applicability.
* * * * *
(b)* * *
(3) Hazardous wastes that are exempt from regulation under
Secs. 261.4 and 261.6(a)(3) (iii) and (iv) of this chapter, and
hazardous wastes that are subject to the special requirements for
conditionally exempt small quantity generators under Sec. 261.5 of this
chapter; and
* * * * *
PART 268--LAND DISPOSAL RESTRICTIONS
12. The authority citation for part 268 continues to read as
follows:
Authority: 42 U.S.C. 6905, 6912(a), 6921, and 6924.
Subpart C--Prohibitions on Land Disposal
13. Section 268.35 is added to subpart C to read as follows:
Sec. 268.35 Waste specific prohibitions-petroleum refining wastes.
(a) Effective February 8, 1999, the wastes specified in 40 CFR part
261 as EPA Hazardous Wastes Numbers K169, K170, K171, and K172, soils
and debris contaminated with these wastes, radioactive wastes mixed
with these hazardous wastes, and soils and debris contaminated with
these radioactive mixed wastes, are prohibited from land disposal.
(b) The requirements of paragraph (a) of this section do not apply
if:
(1) The wastes meet the applicable treatment standards specified in
Subpart D of this part;
(2) Persons have been granted an exemption from a prohibition
pursuant to a petition under Sec. 268.6, with respect to those wastes
and units covered by the petition;
(3) The wastes meet the applicable treatment standards established
pursuant to a petition granted under Sec. 268.44;
(4) Hazardous debris that have met treatment standards in
Sec. 268.40 or in the alternative treatment standards in Sec. 268.45;
or
(5) Persons have been granted an extension to the effective date of
a prohibition pursuant to Sec. 268.5, with respect to these wastes
covered by the extension.
(c) To determine whether a hazardous waste identified in this
section exceeds the applicable treatment standards specified in
Sec. 268.40, the initial generator must test a sample of the waste
extract or the entire waste, depending on whether the treatment
standards are expressed as concentrations in the waste extract or the
waste, or the generator may use knowledge of the waste. If the waste
contains constituents in excess of the applicable Universal Treatment
Standard levels of Sec. 268.48, the waste is prohibited from land
disposal, and all requirements of this part are applicable, except as
otherwise specified.
Subpart D--Treatment Standards
14. In Sec. 268.40, the Table of Treatment Standards is amended by
adding in alphanumeric order new entries for K169, K170, K171, and K172
to read as follows. The appropriate footnotes to the Table of Treatment
Standards are republished without change.
Sec. 268.40 Applicability of treatment standards.
* * * * *
[[Page 42187]]
Treatment Standards for Hazardous Wastes
[Note: NA means not applicable]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Regulated hazardous constituent Wastewaters Nonwastewaters
Waste description and ---------------------------------------------------------------------------------------------------------
Waste code treatment/regulatory Concentration in mg/kg \5\
subcategory \1\ Common Name CAS \2\ No. Concentration in mg/L\3\; or unless noted as ``mg/L TCLP'';
technology code \4\ or technology code \4\
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
K169................. Crude oil tank sediment Benz(a)anthracene...... 56-55-3 0.059.......................... 3.4
from petroleum
refining operations.
Benzene................ 71-43-2 0.14........................... 10
Benzo(g,h,i)perylene... 191-24-2 0.0055......................... 1.8
Chrysene............... 218-01-9 0.059.......................... 3.4
Ethyl benzene.......... 100-41-4 0.057.......................... 10
Fluorene............... 86-73-7 0.059.......................... 3.4
Naphthalene............ 91-20-3 0.059.......................... 5.6
Phenanthrene........... 81-05-8 0.059.......................... 5.6
Pyrene................. 129-00-0 0.067.......................... 8.2
Toluene (Methyl 108-88-3 0.080.......................... 10
Benzene).
Xylene(s) (Total)...... 1330-20-7 0.32........................... 30
K170................. Clarified slurry oil Benz(a)anthracene...... 56-55-3 0.059.......................... 3.4
sediment from
petroleum refining
operations.
Benzene................ 71-43-2 0.14........................... 10
Benzo(g,h,i)perylene... 191-24-2 0.0055......................... 1.8
Chrysene............... 218-01-9 0.059.......................... 3.4
Dibenz(a,h)anthracene.. 53-70-3 0.055 8.2......................
Ethyl benzene.......... 100-41-4 0.057.......................... 10
Fluorene............... 86-73-7 0.059.......................... 3.4
Indeno(1,2,3,-cd)pyrene 193-39-5 0.0055......................... 3.4
Naphthalene............ 91-20-3 0.059.......................... 5.6
Phenanthrene........... 81-05-8 0.059.......................... 5.6
Pyrene................. 129-00-0 0.067.......................... 8.2
Toluene (Methyl 108-88-3 0.080.......................... 10
Benzene).
Xylene(s) (Total)...... 1330-20-7 0.32........................... 30
K171................. Spent hydrotreating Benz(a)anthracene...... 56-55-3 0.059.......................... 3.4
catalyst from
petroleum refining
operations, including
guard beds used to
desulfurize feeds to
other catalytic
reactors (this listing
does not include inert
support media.).
Benzene................ 71-43-2 0.14........................... 10
Chrysene............... 218-01-9 0.059.......................... 3.4
Ethyl benzene.......... 100-41-4 0.057.......................... 10
Naphthalene............ 91-20-3 0.059.......................... 5.6
Phenanthrene........... 81-05-8 0.059.......................... 5.6
Pyrene 129-00-0........ 0.067 8.2............................
Toluene (Methyl 108-88-3 0.080.......................... 10
Benzene).
Xylene(s) (Total)...... 1330-20-7 0.32........................... 30
Arsenic................ 7740-38-2 1.4............................ 5 mg/L TCLP
Nickel................. 7440-02-0 3.98........................... 11.0 mg/L TCLP
Vanadium............... 7440-62-2 4.3............................ 1.6 mg/L TCLP
Reactive sulfides...... NA DEACT.......................... DEACT
K172................. Spent hydrorefining Benzene................ 71-43-2 0.14........................... 10
catalyst from
petroleum refining
operations, including
guard beds used to
desulfurize feeds to
other catalytic
reactors (this listing
does not include inert
support media.).
Ethyl benzene.......... 100-41-4 0.057.......................... 10
Toluene (Methyl 108-88-3 0.080.......................... 10
Benzene).
Xylene(s) (Total)...... 1330-20-7 0.32........................... 30
Antimony............... 7740-36-0 1.9............................ 1.15 mg/L TCLP
Arsenic................ 7740-38-2 1.4............................ 5 mg/L TCLP
Nickel................. 7440-02-0 3.98........................... 11.0 mg/L TCLP
Vanadium............... 7440-62-2 4.3............................ 1.6 mg/L TCLP
Reactive Sulfides...... NA DEACT.......................... DEACT
[[Page 42188]]
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The waste descriptions provided in this table do not replace waste descriptions in 40 CFR part 261. Descriptions of Treatment/Regulatory
Subcategories are provided, as needed, to distinguish between applicability of different standards.
\2\ CAS means Chemical Abstract Services. When the waste code and/or regulated constituents are described as a combination of a chemical with its salts
and/or esters, the CAS number is given for the parent compound only.
\3\ Concentration standards for wastewaters are expressed in mg/L and are based on analysis of composite samples.
\4\ All treatment standards expressed as a Technology Code or combination of Technology Codes are explained in detail in 40 CFR 268.42 Table 1--
Technology Codes and Descriptions of Technology-Based Standards.
\5\ Except for Metals (EP or TCLP) and Cyanides (Total and Amenable) the nonwastewater treatment standards expressed as a concentration were
established, in part, based upon incineration in units operated in accordance with the technical requirements of 40 CFR part 264, Subpart O or part
265 Subpart O, or based upon combustion in fuel substitution units operating in accordance with applicable technical requirements. A facility may
comply with these treatment standards according to provisions in 40 CFR 268.40(d). All concentration standards for nonwastewaters are based on
analysis of grab samples.
* * * * * * *
PART 271--REQUIREMENTS FOR AUTHORIZATION OF STATE HAZARDOUS WASTE
PROGRAMS
15. The authority citation for part 271 continues to read as
follows:
Authority: 42 U.S.C. 6905, 6912(a), and 6926.
Subpart A--Requirements for Final Authorization
16. Section 271.1(j) is amended by adding the following entries to
Table 1 in chronological order by date of publication in the Federal
Register, and by adding the following entries to Table 2 in
chronological order by effective date in the Federal Register, to read
as follows:
Sec. 271.1 Purpose and scope.
* * * * *
(j) * * *
Table 1.--Regulations Implementing the Hazardous and Solid Waste Amendments of 1984
----------------------------------------------------------------------------------------------------------------
Federal Register
Promulgation date Title of regulation reference Effective date
----------------------------------------------------------------------------------------------------------------
* * * * * *
August 6, 1998..................... Petroleum Refining [Insert FR page February 8, 1999.
Process Wastes. numbers].
----------------------------------------------------------------------------------------------------------------
* * * *
* * *
Table 2.--Self-Implementing Provisions of the Solid Waste Amendments of 1984
----------------------------------------------------------------------------------------------------------------
Self-implementing
Effective date provision RCRA citation Federal Register reference
----------------------------------------------------------------------------------------------------------------
* * * * * *
February 8, 1999................... Prohibition on land 3004(g)(4) (C) and August 6, 1998. 63 FR [Insert
disposal of newly 3004 (m). page numbers]
listed and
identified wastes;
and prohibition on
land disposal of
radioactive waste
mixed with the newly
listed or identified
wastes, including
soil and debris.
* * * * * *
*
----------------------------------------------------------------------------------------------------------------
* * * *
* * *
PART 302--DESIGNATION, REPORTABLE QUANTITIES, AND NOTIFICATION
17. The authority citation for part 302 continues to read as
follows:
Authority: 42 U.S.C. 9602, 9603, and 9604; 33 U.S.C. 1321 and
1361.
18. In Sec. 302.4, table 302.4 is amended by adding footnote f and
the following new entries in alphanumerical order at the end of the
table to read as follows:
Sec. 302.4 Designation of hazardous substances.
* * * *
* * *
[[Page 42189]]
Table 302.4--List of Hazardous Substances and Reportable Quantities
[Note: All Comments/Notes Are Located at the End of This Table]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Statutory Final RQ
Hazardous substance CASRN Regulatory synonyms ------------- Code RCRA waste No. -------------------------------
RQ Category Pounds (Kg)
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
K169f........................... ................... ................... \1\* 4 K169 A 10(4.54)
Crude oil storage tank sediment
from petroleum refining
operations.
K170f........................... ................... ................... \1\* 4 K170 X 1 (0.454)
Clarified slurry oil tank
sediment and/or in-line filter/
separation solids from
petroleum refining operations.
K171f........................... ................... ................... \1\* 4 K171 X 1 (0.454)
Spent hydrotreating catalyst
from petroleum refining
operations. (This listing does
not include inert support
media.)
K172f........................... ................... ................... \1\* 4 K172 X 1 (0.454)
Spent hydrorefining catalyst
from petroleum refining
operations. (This listing does
not include inert support
media.)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Indicates the statutory sources as defined by 1, 2, 3, and 4 below.
* * * * * * *
\1\*--Indicates that the 1-pound RQ is a CERCLA statutory RQ.
* * * * * * *
f See 40 CFR 302.6(b)(1) for application of the mixture rule to this hazardous waste.
19. Section 302.6 is amended by revising paragraphs (b)(1)(i) and
(b)(1)(ii) and by adding paragraph (b)(1)(iii) to read as follows:
Sec. 302.6 Notification requirements.
* * * * *
(b) * * *
(1) * * *
(i) If the quantity of all of the hazardous constituent(s) of the
mixture or solution is known, notification is required where an RQ or
more of any hazardous constituent is released;
(ii) If the quantity of one or more of the hazardous constituent(s)
of the mixture or solution is unknown, notification is required where
the total amount of the mixture or solution released equals or exceeds
the RQ for the hazardous constituent with the lowest RQ; or
(iii) For waste streams K169, K170, K171, and K172, knowledge of
the quantity of all of the hazardous constituent(s) may be assumed,
based on the following maximum observed constituent concentrations
identified by EPA:
------------------------------------------------------------------------
Waste Constituent Max ppm
------------------------------------------------------------------------
K169................ Benzene.............................. 220.0
K170................ Benzene.............................. 1.2
Benzo (a) pyrene..................... 230.0
Dibenz (a,h) anthracene.............. 49.0
Benzo (a) anthracene................. 390.0
Benzo (b) fluoranthene............... 110.0
Benzo (k) fluoranthene............... 110.0
3-Methylcholanthrene................. 27.0
7,12-Dimethylbenz (a) anthracene..... 1,200.0
K171................ Benzene.............................. 500.0
Arsenic.............................. 1,600.0
K172................ Benzene.............................. 100.0
Arsenic.............................. 730.0
------------------------------------------------------------------------
* * * * *
[FR Doc. 98-19929 Filed 8-5-98; 8:45 am]
BILLING CODE 6560-50-P