[Federal Register Volume 69, Number 54 (Friday, March 19, 2004)]
[Proposed Rules]
[Pages 12995-13011]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-6216]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 261
[FRL-7638-1]
Hazardous Waste Management System; Proposed Exclusion for
Identification and Listing of Hazardous Waste
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: The EPA (also, ``the Agency'' or ``we'' in this preamble) is
proposing to grant a petition submitted by General Electric Company
(GE), King of Prussia, Pennsylvania, to exclude (or ``delist''), on a
one-time basis, certain solid wastes that have been deposited and/or
accumulated in two (2) on-site drying beds and two (2) on-site basins
referred to by GE as ``surface impoundments'' at its RCA del Caribe
facility in Barceloneta, Puerto Rico from the lists of hazardous wastes
contained in the regulations. These drying beds and basins were used
exclusively for disposal of its chemical etching wastewater treatment
plant (WWTP) sludge from 1971 to 1978.
The Agency has tentatively decided to grant the petition based on
an evaluation of waste-specific information provided by GE. This
proposed decision, if finalized, would conditionally exclude the
petitioned waste from the requirements of hazardous waste regulations
under the Resource Conservation and Recovery Act (RCRA).
If finalized, the EPA would conclude that GE's petitioned waste is
nonhazardous with respect to the original listing criteria or factors
which could cause the waste to be hazardous. The waste would still be
subject to Local, State (as used herein the term State includes the
Commonwealth of Puerto Rico) and Federal regulations for nonhazardous
solid waste.
DATES: The Agency will accept public comments on this proposed decision
until May 3, 2004. Comments postmarked after the close of the comment
period will be stamped ``late.'' These ``late'' comments may not be
considered in formulating a final decision.
Any person may request a hearing on this proposed rule by filing a
written request by April 5, 2004. Pursuant to 40 CFR 260.20(d), the
request must state the issue to be raised and explain why written
comments would not suffice to communicate the person's views.
ADDRESSES: Please send two copies of your comments to Ernst J. Jabouin,
RCRA Program Branch (2DEPP-RPB), Environmental Protection Agency,
Region 2, 290 Broadway, New York, NY 10007-1866.
Any person may request a hearing on this proposed decision by
filing a request to the Director, of the Division of Environmental
Planning and Protection (DEPP), Environmental Protection Agency, Region
2, 290 Broadway, New York, NY 10007-1866.
FOR FURTHER INFORMATION CONTACT: For technical information concerning
this document, contact Ernst J. Jabouin at the address above or at 212-
637-4104. The RCRA regulatory docket for this proposed rule is located
at the EPA Region 2, 290 Broadway, New York, NY 10007-1866, and is
available for viewing from 8 a.m. to 4 p.m., Monday through Friday,
excluding federal holidays. Call Ernst J. Jabouin at 212-637-4104 for
appointments. The public may copy material from the regulatory docket
at $0.15 per page.
SUPPLEMENTARY INFORMATION:
I. Overview Information
A. What action is EPA proposing?
B. Why is EPA proposing to approve this delisting?
C. How will GE manage the waste if it is delisted?
D. When would EPA finalize the proposed delisting?
E. How would this action affect the states?
II. Background
A. What is the history of the delisting program?
B. What is a delisting petition, and what does it require of a
petitioner?
C. What factors must EPA consider in deciding whether to grant a
delisting petition?
III. EPA's Evaluation of the Waste Information and Data
A. What wastes did GE petition EPA to delist?
B. What information and analyses did GE submit to support this
petition?
C. How did GE generate the petitioned waste?
D. How did GE sample and analyze the data in this petition?
E. What were the results of GE's analysis?
IV. Methodology for Risk Assessments
A. How did EPA evaluate the risk of delisting this waste?
B. What risk assessment methods has the Agency used in previous
delisting determinations that are being used in this proposal?
V. Evaluation of This Petition
A. What other factors did EPA consider in its evaluation?
B. What did EPA conclude about GE's analysis?
C. What is EPA's evaluation of this delisting petition?
VI. Conditions for Exclusion
A. What are the maximum allowable concentrations of hazardous
constituents for the waste?
B. What are the conditions of the exclusion?
C. What happens if GE fails to meet the conditions of the
exclusion?
VII. Regulatory Impact
VIII. Regulatory Flexibility Act
IX. Paperwork Reduction Act
X. Unfunded Mandates Reform Act
XI. Executive Order 12875
XII. Executive Order 13045
XIII. Executive Order 13084
XIV. Executive Order 13132
XV. National Technology Transfer and Advancement Act
I. Overview Information
A. What Action Is EPA Proposing?
The EPA is proposing to grant GE's petition to have its wastewater
treatment sludge excluded, or delisted, from the definition of a
hazardous waste. The Agency evaluated the petition using a fate and
transport model to predict the concentration of hazardous constituents
which could be released from the petitioned waste after it is disposed.
B. Why Is EPA Proposing To Approve This Delisting?
GE petitioned EPA to exclude, or delist, the wastewater treatment
sludge because GE believes that the petitioned waste does not meet the
criteria for which EPA listed it. GE also believes there are no
additional constituents or factors that could cause the wastes to be
hazardous. Based on EPA's review described below, the Agency has
tentatively determined that the waste can be considered nonhazardous.
In reviewing this petition, EPA considered the original listing
criteria and the additional factors as required by the Hazardous and
Solid Waste Amendments of 1984 (HSWA). See section 222 of HSWA, 42
U.S.C. 6921(f), and 40 CFR 260.22 (d)(2) through (4). EPA evaluated the
petitioned waste against the listing criteria and factors cited in 40
CFR 261.11(a)(2) and (3).
[[Page 12996]]
The Agency also evaluated the waste for other factors including (1)
the toxicity of the constituents; (2) the concentration of the
constituents in the waste; (3) the tendency of the hazardous
constituents to migrate and to bioaccumulate; (4) persistence in the
environment of any constituents released from the waste; (5) plausible
and specific types of management of the petitioned waste; (6) the
quantity of waste produced; and (7) waste variability.
EPA believes that the petitioned waste does not meet the criteria
for which the waste was listed, and has tentatively decided to delist
this waste from the former RCA del Caribe Facility.
C. How Will GE Manage the Waste If It Is Delisted?
If the petitioned waste is delisted, GE must dispose of it in a
Subtitle D landfill which is permitted, licensed, or registered by a
state (as used herein includes the Commonwealth of Puerto Rico) to
manage industrial waste. This exclusion does not change the regulatory
status of the drying beds and on-site basins at the facility in
Barceloneta, Puerto Rico where the waste has been disposed.
D. When Would EPA Finalize the Proposed Delisting?
HSWA specifically requires EPA to provide notice and an opportunity
for comment before granting or denying a final exclusion. Thus, EPA
will not make a final decision or grant an exclusion until it has
addressed all timely public comments (including those at public
hearings, if any) on today's proposal.
Since this rule would reduce the existing requirements for persons
generating hazardous wastes, the regulated community does not need a
six-month period to come into compliance in accordance with section
3010 of RCRA as amended by HSWA. Therefore, the exclusion would become
effective upon finalization.
E. How Would This Action Affect the States?
Because EPA is issuing today's exclusion under the federal RCRA
delisting program, only states subject to federal RCRA delisting
provisions would be affected. This exclusion may not be effective in
states having a dual system that includes federal RCRA requirements and
their own requirements, or in states which have received authorization
to make their own delisting decisions (note that the term ``State'' as
used herein includes the Commonwealth of Puerto Rico).
Under section 3009 of RCRA, EPA allows states to impose their own
non-RCRA regulatory requirements that are more stringent than EPA's.
These more stringent requirements may include a provision that
prohibits a federally issued exclusion from taking effect in the state.
Because a dual system (that is, both federal (RCRA) and state (non-
RCRA) programs) may regulate a petitioner's waste, we urge petitioner
to contact the state regulatory authority to establish the status of
its wastes under the state law.
EPA has also authorized some states to administer a delisting
program in place of the federal program, that is, to make state
delisting decisions. Therefore, this exclusion does not apply in those
authorized states. If GE transports the petitioned waste to or manages
the waste in any state with delisting authorization, GE must obtain a
delisting from that state before it can manage the waste as
nonhazardous in the state.
II. Background
A. What Is the History of the Delisting Program?
The EPA published an amended list of hazardous wastes from
nonspecific and specific sources on January 16, 1981, as part of its
final and interim final regulations implementing section 3001 of RCRA.
The EPA has amended this list several times and published it in 40 CFR
261.31 and 261.32.
The Agency lists wastes as hazardous because: (1) they typically
and frequently exhibit one or more of the characteristics of hazardous
wastes identified in subpart C of part 261 (that is, ignitability,
corrosivity, reactivity, and toxicity) or (2) they meet the criteria
for listing contained in Sec. 261.11(a)(2) or (3).
Individual waste streams may vary depending on raw materials,
industrial processes, and other factors. Thus, while a waste described
in these regulations generally is hazardous, a specific waste from an
individual facility meeting the listing description may not be.
For this reason, 40 CFR 260.20 and 260.22 provide an exclusion
procedure, called delisting, which allows a person to demonstrate that
EPA should not regulate a specific waste from a particular generating
facility as a hazardous waste.
B. What Is a Delisting Petition, and What Does It Require of a
Petitioner?
A delisting petition is a request from a facility to EPA or an
authorized state to exclude waste generated at a particular facility
from the list of hazardous wastes.
In a delisting petition, the petitioner must show the waste
generated does not meet any of the criteria for listed wastes and does
not exhibit any of the hazardous waste characteristics in 40 CFR part
261, subpart C. The criteria for which EPA lists a waste are in 40 CFR
261.11 and in the background documents. The petitioner must also
present sufficient information to determine whether factors other than
those for which the waste was listed warrant retaining it as a
hazardous waste. (See 40 CFR 260.22, 42 U.S.C. 6921(f) and the
background documents for the listed wastes).
A generator remains obligated under RCRA to confirm that its waste
remains nonhazardous based on the hazardous waste characteristics even
if EPA has ``delisted'' the waste.
C. What Factors Must EPA Consider in Deciding Whether To Grant a
Delisting Petition?
EPA must also consider as a hazardous waste, a mixture containing
listed hazardous wastes and wastes derived from treating, storing, or
disposing of a listed hazardous waste. See 40 CFR 261.3(a)(2)(iv) and
(c)(2)(i), called the ``mixture'' and ``derived-from'' rules,
respectively. These wastes are also eligible for exclusion and remain
hazardous wastes until excluded.
The ``mixture'' and ``derived-from'' rules are now final, after
having been vacated, remanded, and reinstated.
III. EPA's Evaluation of the Waste Information and Data
A. What Wastes Did GE Petition EPA To Delist?
On November 20, 1997, GE petitioned EPA Region 2 to exclude an
estimated volume of hazardous wastes ranging from 5,000 to 15,000 cubic
yards from the list of hazardous wastes contained in 40 CFR 261.31.
These wastes were generated and disposed of at GE's facility in
Barceloneta, PR, formerly known as the RCA del Caribe facility. This
facility is included on EPA's National Priority List and was the
subject of a Superfund Remedial Investigation, Feasibility Study and
Record of Decision. The wastes are described in GE's petition as EPA
Hazardous Waste Number F006 wastewater treatment sludge that was
generated from chemical etching operation and accumulated in two drying
beds and two basins where the sludge mixed with soil. F006 is defined
[[Page 12997]]
as ``Wastewater treatment sludges from electroplating operations except
from the following processes: (1) Sulfuric acid anodizing of aluminum;
(2) tin plating on carbon steel; (3) zinc plating (segregated basis) on
carbon steel; (4) aluminum or zinc-aluminum steel; (5) cleaning/
stripping associated with tin, zinc and aluminum plating on carbon
steel; and (6) chemical etching and milling of aluminum.'' The
constituents of concern for which F006 is listed are cadmium,
hexavalent chromium, nickel and complexed cyanide.
B. What Information and Analyses Did GE Submit To Support This
Petition?
To support its petition, GE submitted (1) descriptions and
schematic diagrams of its manufacturing and wastewater treatment
processes, including historical information on past waste generation
and management practices; (2) detailed chemical and physical analysis
of the sludge (see section III.D.); and (3) environmental monitoring
data from past and recent studies of the facility, including
groundwater data from wells located around the two drying beds and two
basins. GE submitted a signed certification of accuracy and
responsibility statement set forth in 40 CFR 260.22(i)(12). By this
certification, GE attests that all submitted information is true,
accurate and complete.
C. How Did GE Generate the Petitioned Waste?
According to information submitted by GE, the RCA del Caribe, Inc.
Barceloneta facility began generating wastewater treatment sludge from
its chemical etching operation in 1971 until the plant ceased
operations in April 1987. During that time, the facility manufactured
aperture (or shadow) masks for television picture tubes. A shadow mask
is a specially prepared, paper thin, carbon steel screen used in
cathode ray tubes to direct the electron beam to the television screen.
The shadow masks were manufactured using a photolithographic/chemical
etching process with the photolithographic step to establish locations
of holes and slots and the chemical etching step to produce the desired
holes and slots. During the process thin sheets of carbon steel which
contained a thin layer of grease to protect the metal from corrosion
and rusting were rinsed with tap water, detergent, caustic cleaning
solution (sodium hydroxide), and deionized water. Rinses generated from
this process were directed to the wastewater treatment plant. Then, a
photoresist solution or glazing glue composed of casein, potassium or
ammonium dichromate and a disinfectant (Borax) was baked to the surface
of the clean sheet of steel. Once this process known as sensitizing is
performed, the sheet was exposed to Ultra violet (UV) light to
photographically develop the mask pattern. Developing or rinsing the UV
exposed sheets with deionized water to remove unexposed photoresist
solution from the sheets to exposed bare portions to be etched upon
application of a wetting agent and oven-drying the sheet. These
wastewaters, which contained unreacted photoresist solution, were
directed to the wastewater treatment plant and were a source of
chromium (from chromium dichromate) for the influent to the treatment
plant and the resulting sludge. A mixture of hydrochloric acid and
ferric chloride was used to chemically etch holes and slots in
unprotected steel sheet portions. During the reaction, ferric ion
(Fe+3) reacted with metallic ion (Fe+0) to
produce ferrous ion (Fe+2) as follows:
2 Fe+3 + Fe+0 =3 Fe+2
Spent ferric chloride etching solution was recovered for reuse in a
closed-loop system. Final rinsing followed the etching process. Rinsed
water from this step contained chromium, ferric chloride, and ferrous
chloride and were directed to the wastewater treatment plant.
The manufacturing process contributed to a chromium-reducing
environment such that hexavalent chromium, or Cr(VI) would normally be
reduced to trivalent chromium, or Cr(III). Because the etching solution
was recovered and recycled in a closed loop system, it accumulated
excess ferrous ions which were periodically converted elsewhere in the
loop system to ferric ion by adding chloride.
3 Fe+2 + 3/2 Cl2=3 Fe+3 + 3
Cl
However, for safety reasons, the regeneration was not allowed to go to
completion. Excess chlorine in the etching solution would have evolved
into hazardous chlorine gas. Therefore, some residual ferrous ion was
always left in the regenerated solution. The ramification is that at
low pH, the Eh (redox potential) of a solution containing both ferrous
and ferric ions lies within a narrow range in which Cr (III) is stable,
and Cr(VI) is not. Thus, any chromium in the excess etchant solution
was trivalent, not hexavalent.
All the wastewaters described above were blended prior to
treatment. This results in reduction of hexavalent chromium to
trivalent chromium species. The combined stream was pumped to the
wastewater treatment plant where it was treated with caustic soda to
effect precipitation of metals, chiefly ferric dioxide. A polymer was
added to the metal in a clarifier. Clarified effluent flowed by gravity
into a permitted natural sinkhole while the sludge underflow was
discharged by gravity to two on-site sludge drying beds and two basins
referred to by GE as ``surface impoundments'' (SI).
D. How Did GE Sample and Analyze the Data in This Petition?
GE analyzed the drying beds sludge, basins sludge, basins soil and
groundwater samples from the monitoring well network for hazardous
constituents listed in 40 CFR part 264, appendix IX and for other
parameters.
GE's sampling strategy for contaminants consisted of dividing each
drying beds and each basin surface area into four equal quadrants.
Composite samples were collected from each quadrant. Each composite
sample within that quadrant was composed of samples from five shallow
borings and five grab samples for the surface composite samples. The
borings and composite grab samples were located at the center and five
to fifteen feet from the center (toward the corner), of each quadrant.
Each boring sample was collected by making a composite of the entire
thickness of the sludge representing the total depth of the unit
sampled. The grab samples were collected from the surface to 0.5 feet.
Contaminated soil around the basins were sampled in a fashion similar
to what is described above for both surface and borings soil samples.
The Agency evaluated the petitioned waste using these samples in
combination with data from the Remedial Investigation.
To quantify the total constituent and leachate concentrations, GE
used the Contract Laboratory Program Scope of Work, (CLP SOW, April
1990) and SW-846 Methods 6010/7000 series: for arsenic, barium,
cadmium, chromium, hexavalent chromium, lead, mercury, nickel,
selenium, and silver; 8240 for Appendix IX Volatile Organic Compounds
(VOCs); 8270 for Appendix IX Semi-Volatile Organic Compounds (SVOCs);
GE used these methods along with the Toxicity Characteristic Leaching
Procedure (TCLP), (SW-846 Method 1311) to determine leachate
concentrations of metals, VOCs, and SVOCs. Characteristic testing of
soil and sludge samples also included analysis of ignitability (SW-846
Method 1010) and corrosivity (SW-846 Method 9095).
E. What Were the Results of GE's Analysis?
The maximum total and leachate concentrations for toxicity
characteristic metals and nickel, total cyanide in GE's
[[Page 12998]]
waste samples are summarized in Table 1. Since none of the sludge
samples failed for toxicity, no soil samples were subjected to TCLP
leachate analysis. Also, there was no detection of significant
concentrations of organics in either the soil or the sludge when
analyzed for ``Appendix 9 constituents.'' As a result, neither the
sludge nor the soil were subjected to TCLP organic analysis. EPA does
not generally verify submitted test data before proposing delisting
decisions. The sworn affidavit submitted with the petition binds the
petitioner to present truthful and accurate results.
Table 1
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Maximum observed total concentration (mg/kg) Maximum observed Leachate
------------------------------------------------ concentration (mg/L TCLP)
--------------------------------
Sludge drying Sludge SI Soil around Sludge drying Sludge SI
beds basins basins beds basins
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Arsenic........................ 17.4J 27.4 91.0 0.022 ND
Barium......................... 21.1 38.6 140 0.432 0.716
Cadmium........................ ND 1.2 3.0 ND ND
Chromium....................... 5360 8400 4370 0.157 ND
Lead........................... ND 677J 94.3J ND ND
Mercury........................ 1.1J 1.6 0.49 ND ND
Nickel......................... 43.3J 94J 64.4J 0.0214 ND
Selenium....................... 0.30J ND 0.61J ND ND
Silver......................... 26.4J 0.66 22.1 ND ND
Cyanide........................ ND 46.5 ND ND ND
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Note: ND=Not Detected
J=value is an estimated quantity.
IV. Methodology for Risk Assessments
A. How Did EPA Evaluate the Risk of Delisting This Waste?
For this delisting determination, EPA used information gathered to
identify plausible exposure routes (i.e., groundwater, surface water,
air) to hazardous constituents present in the petitioned waste. EPA
estimated the risk posed by the waste if disposed of in an unlined
Subtitle D landfill which, under a plausible mismanagement scenario,
did not receive daily cover for 30 days at a time. Constituents of
concern are assumed to migrate to a receptor through groundwater, air,
and surface water routes. EPA used a Windows based software tool, the
Delisting Risk Assessment Software Program (DRAS) developed by Region
6, to estimate the potential releases of waste constituents and to
predict the risk associated with those releases. A detailed description
of DRAS and the fate, transport and risk models it uses follows.
1. Introduction
During a delisting determination, the Agency uses risk assessment
methodologies to predict the concentration of hazardous constituents
released from the petitioned waste after disposal to determine the
potential impact on human health and the environment. The DRAS program
has been used to estimate the potential releases of waste constituents
to waste management units. The program also predicts the risk
associated with exposure to those releases using fate and transport
mechanisms to predict releases and risk assessment algorithms to
estimate adverse effects from exposure to those chemical releases. The
DRAS computes chemical-specific exit values or ``delisting levels.''
The delisting levels are calculated using modeled, medium-specific
chemical concentrations and standard EPA exposure assessment and risk
characterization algorithms. EPA detailed all chemical release,
exposure, and risk characterization methodologies in the EPA Region 6
RCRA delisting Technical Support Document.
The Agency has used the maximum estimated annual waste volume and
the maximum reported leachate and total waste constituent
concentrations as the input data into the DRAS program to generate
compliance point concentrations and estimate risk. The compliance point
is the location of an individual exposed to potential releases of
delisted wastes for the purpose of evaluating risk. Compliance point
concentrations are generated in a two-part process. First, the DRAS
back-calculates a waste constituent concentration that an individual
(receptor) may be exposed to without unacceptable risk. Then, knowing
the maximum concentration permitted at the compliance point, the fate
and transport models are used to back-calculate the maximum permissible
concentration at the waste management unit that could be disposed of
without exceeding the compliance point concentration.
The risk assessment performed by the DRAS program which underlies
the proposed rule is based upon a comprehensive approach to evaluating
the movement of waste constituents from their waste management units,
through different routes of exposure or pathways, to the points where
human and ecological receptors are potentially exposed to these
constituents. This risk assessment is being used in today's proposed
rule to determine whether the petitioned RCRA listed waste can be
defined as ``low-risk'' waste, able to exit the Subtitle C system and
be managed in Subtitle D units. Low risk wastes are generally defined
by Region 2 as wastes with a cancer risk of no more than 1 x
10-6 or a hazard quotient of no more than 1.0. A cancer risk
of 1 x 10-6 indicates a one in 1,000,000 probability of an
individual developing cancer over a lifetime. For noncarcinogenic
chemicals, a hazard quotient of one represents potential exposure equal
to the safe toxicity threshold value. The program back-calculates
allowable waste constituent concentrations at the selected risk levels.
Although the pathway of ingestion of contaminated groundwater may
be appropriate to propose exit levels for some wastes and constituents,
it may not be protective for others, depending on the physical and
chemical properties of each waste constituent. Some constituents have a
high potential to bioaccumulate or bioconcentrate in living organisms.
Pathways in which
[[Page 12999]]
these constituents come in contact with fish would be important to
evaluate.
The DRAS program performs an extensive risk assessment that
examines numerous exposure pathways, rather than just the groundwater
ingestion pathway. The DRAS program evaluates exposures associated with
managing wastes in Subtitle D landfills or surface impoundments.
Elements of the risk assessment procedure performed by the DRAS that
support this proposal have undergone review by the Science Advisory
Board (SAB) and EPA's Office of Research and Development (ORD). The use
of the Composite Model for leachate migration with Transformation
Products (CMTP) as used in the DRAS was favorably received by the SAB.
ORD reviewed all other aspects of the DRAS program and responded
favorably with comments. All ORD comments were addressed and
incorporated into the DRAS program.
2. What Conditions Does the Agency Use in Determining Whether a Waste
May Be Delisted?
The EPA's approach in RCRA delisting risk analyses has typically
been to represent a reasonable worst-case waste disposal scenario for
the petitioned waste rather than use of site-specific factors. The
Agency believes that a reasonable worst-case scenario results in
conservative values for the compliance point concentrations and is
appropriate when determining whether a waste should be relieved of the
management constraints of RCRA Subtitle C. Site-specific factors (e.g.,
site hydrogeology) are not considered because a delisted waste is no
longer subject to hazardous waste control, and therefore, the Agency is
generally unable to predict and does not control where and how a waste
will be managed after delisting. However, the Agency may impose
conditions for exclusion so that the delisted waste is still managed in
a manner that is protective of human health and the environment (refer
to section VI.B. of this preamble).
3. How Is the Risk Assessment in the DRAS Program Structured?
The assessment estimated the risk associated with constituent-
specific concentrations in the petitioned waste at the management unit
that could be expected to result in an acceptable exposure to human or
ecological receptors (determined through using the toxicity benchmarks
such as reference doses--RfDs). The risk assessment took into account
the various pathways by which waste constituents may move through the
environment from the waste management unit to a receptor. The DRAS uses
the fate and transport mechanisms to predict waste constituent
movement. The potential exposure pathways considered in the assessment
are not all-inclusive, but were selected to reflect those that might be
commonly associated with the management of wastes in Subtitle D units.
The management units could potentially be located in the range of
environments that exist across the United States. Various environments
have differing characteristics (e.g., meteorological conditions, soil
type) with some environments more conducive for the movement of certain
constituents in certain pathways. Conditions resulting in a
conservative evaluation were used for each pathway, regardless of
whether or not these conditions are likely to occur simultaneously at
any one location. The assessment was structured using a deterministic
approach. A deterministic approach uses a single, point estimate of the
value of each input or parameter and calculates a single result based
on those point estimates. The assessment used the best data available
to select typical (i.e., approximately 50th percentile) and high-end
(i.e., approximately 90th percentile) values for each parameter. The
DRAS code which performs the assessment is constructed as a set of
calculations that begin with an acceptable exposure level for a
constituent to a receptor, and back-calculates to a waste constituent
concentration in the management unit that corresponds to the acceptable
risk level.
The steps of the assessment which provide estimates of acceptable
constituent-specific concentrations in waste include the following:
Step 1--Specify acceptable risk levels for each constituent and
each receptor.
Step 2--Specify the exposure medium. Using the toxicity benchmarks
as a starting point and the exposure equations, the assessment back
calculates the concentration of contaminant in the medium (e.g., air,
water, soil) that corresponds to ``acceptable'' exposure at the
specified risk level. The exposure equations coded into the DRAS
software include a quantitative description of how a receptor comes
into contact with the contaminant and how much the receptor takes in
through specific mechanisms (e.g., ingestion, inhalation, dermal
adsorption) over some specified period of time.
Step 3--Calculate the point of release concentration from the
exposure concentration. Based on the back-calculated concentration in
the exposure medium (from Step 2), the concentration in the medium to
which the contaminant is released to the environment (i.e., air, soil,
groundwater) for each pathway/receptor was modeled. The end result of
this calculation is a waste constituent concentration at the point of
release from the waste management unit (where the exempted waste is
disposed) that will not result in adverse effects to human health and
the environment.
4. When Assessing the Risk of the Exempted Waste, Where Does the DRAS
Assume the Waste is Deposited?
The DRAS risk assessment evaluates risks associated with petitioned
RCRA wastes deposited to two waste management scenarios: landfills and
surface impoundments. A landfill waste management scenario is used for
the evaluation of solid wastes, while a surface impoundment waste
management scenario is used for the evaluation of liquid wastes. The
determination of whether a waste is a liquid waste is made using EPA
approved Test Method 9095, referred to as the Paint Filter Test. Data
to characterize landfills were obtained from a 1987 nationwide survey
of industrial Subtitle D landfills. For releases to groundwater, EPA's
Composite Model for leachate migration with Transformation Products
(EPACMTP) fate and transport model was used by DRAS. The model assumes
that solid wastes remain uncovered for thirty days after disposal and
that the landfill will finally be covered with a 2-foot-thick native
soil layer. The Subtitle D landfill is assumed to be unlined or if
lined, that any liner at the base of the landfill will eventually
completely fail.
The DRAS assumes that liquid industrial wastes are disposed of in
an unlined surface impoundment with a sludge or sediment layer at the
base of the impoundment and that releases of contaminants originate
from the surface impoundment. The surface impoundment is taken to have
a 20-year operational life. After this period, the impoundment may be
filled in, or simply abandoned. In either case, the remaining waste in
the impoundment will leach into the unsaturated zone relatively
quickly. Therefore, the duration of the leaching period in the modeling
analysis is set equal to 20-years.
5. What Types of Chemical Releases From the Waste Management Units Does
the DRAS Evaluate?
The DRAS evaluates chemical releases of waste constituents from the
waste management units to air, surface runoff and ground water. Using
the
[[Page 13000]]
EPACMTP fate and transport model, DRAS evaluates the potential release
of waste contaminants to the ground water. In this evaluation, the
differences between waste management units are represented by different
values or frequency distributions of the source-specific parameters.
Source-specific parameters used by the EPACMTP predict releases to the
ground water from landfills include:
Capacity and dimensions of the waste management unit;
Leachate concentration;
Infiltration and recharge rates;
Pulse duration;
Fraction of hazardous waste in the waste management unit;
Density of the waste and;
Concentration of the chemical constituent in the hazardous waste
The source-specific parameters used by the model for surface
impoundments include:
The area;
The ponding depth (such as the depth of liquid in the impoundment) and;
The thickness and hydraulic conductivity of the sludge or sediment
layer at the bottom of the impoundment
Data on the areas, volumes, and locations of waste management units
were obtained from the 1987 EPA Survey of Industrial Subtitle D waste
facilities in the United States. Derivation of the parameters for each
type of waste management unit is described in the EPACMTP Background
Document and User's Guide.
For finite-source scenarios, simulations are performed for
transient conditions, and the source is assumed to be a pulse of finite
duration. In the case of landfills, the pulse duration is based on the
initial amount of contaminant in the landfill, infiltration rate,
landfill dimensions, waste and leachate concentration, and waste
density. For surface impoundments, the duration of the leaching period
is determined by the waste management unit's lifetime (the default
value is 20 years). For a finite-source scenario, the model can
calculate either the peak receptor well concentration for
noncarcinogens or an average concentration over a specified period for
carcinogens. The finite-source methodology in the EPACMTP is discussed
in detail in the background document.
The DRAS evaluates releases of waste constituents from the waste
management to the air. Releases of chemicals to the air may be in the
form of either particulates or volatile concentrations. Inhalation of
particulates and their absorption into the lungs at the point of
exposure (POE) and air deposition of particulates and subsequent
ingestion of the soil-waste mixture at the POE are a function of
particulate releases. The DRAS calculates particulate emissions
resulting from wind erosion of soil-waste surfaces, from vehicular
traffic, and from waste loading and unloading. To estimate the
respirable particulate emissions resulting from wind erosion of
surfaces with an infinite source of erodible particles, DRAS uses the
methodology documented in Rapid Assessment of Exposure to Particulate
Emissions from Surface Contamination Sites (RAEPE). The methodologies
documented in Compilation of Air Pollutant Emission Factors, Volume 1:
Stationary Point and Area Sources (AP-42) were employed to calculate
the dust and particulate emissions resulting both from vehicular
traffic and from waste loading and unloading operations at a facility.
Particulate emission rates computed using these methodologies were
summed and entered in the Ambient Air Dispersion Model, a steady-state,
Gaussian plume dispersion model developed by EPA to predict the
concentrations of constituents 1,000 feet downwind of a hypothetical
land disposal facility. For a complete description and discussion,
refer to the 1985 Ambient Air Dispersion Model (AADM). The model
assumes that:
(1) The emission rate is constant over time;
(2) The emissions arise from an upwind virtual point source with
emissions occurring at ground level and;
(3) No atmospheric destruction or decay of the constituent occurs
The DRAS assumes typical or conservative values for all variables
that are likely to influence the potential for soil erosion, including
wind velocity and vegetative cover. The AADM unit dimension assumptions
were modified to more closely resemble a landfill's. The DRAS equations
compute emissions resulting from wind erosion, vehicular traffic, and
waste loading and unloading. These equations are thoroughly described
in the Region 6 delisting Technical Support Document. For the landfill
waste disposal scenario, the DRAS assumed that no vegetative cover is
present, thereby assuming enhanced erodability of soil or waste. The
mean annual wind speed is assumed to be 4 meters per second. This value
represents the average of the wind speeds registered at U.S.
climatological stations as documented in Table 4-1 of RAEPE. The DRAS
assumes a month's (30 days') worth of waste would be uncovered at any
one time.
Although particulates greater than 10 micrometers (um) in size
generally are not considered respirable, the DRAS calculates the
emission rate for particle sizes up to 30um in order to assess the
potential impact of deposition and ingestion of such particulates using
the distributions of wind-eroded particulates presented in RAEPE.
Specifically, these distributions indicate that the release rate for
particulates up to 30 um in size should be approximately twice the
release rate calculated for particulates 10 um in size. The DRAS
calculates the total annual average emissions of respirable
particulates by summing for wind erosion, for vehicle travel, and for
waste loading and unloading operations. The DRAS evaluates air
deposition of the annual total emissions of particulates less than or
equal to 30 um in size to soil 1,000 feet from the edge of a disposal
unit. DRAS calculates the resulting soil concentration after one year
of accumulation, conservatively assuming no constituent removal (no
leaching, volatilization, soil erosion, or degradation).
The DRAS also evaluates the atmospheric transport and inhalation of
volatile constituents which was developed by EPA's Office of Air
Quality Planning and Standards (OAQPS) and has been recommended for use
in risk assessments conducted under the Superfund program. The DRAS
program, is currently being revised to incorporate Shen's modification
of Farmer's equation which will result in a better estimate of volatile
emissions. Estimates of emissions of VOCs from disposal of wastewaters
in surface impoundments are computed with EPA's Surface Impoundment
Modeling System (SIMS). SIMS was developed by EPA's OAQPS. Further
information can be found in the Background Document for the Surface
Impoundment Modeling System Version 2.0. The volatile emission rates
derived from the respective waste management scenario are used by the
AADM steady-state Gaussian plume dispersion model to predict the
concentrations of constituents 1,000 feet downwind of a hypothetical
disposal facility.
The DRAS evaluates potential releases of waste constituents to
accessible surface waters. Exposure through the surface water pathway
results from erosion of hazardous materials from the surface of a solid
waste landfill and transport of these constituents to nearby surface
water bodies. The DRAS uses the universal soil loss equation (USLE) to
compute long-term soil and waste
[[Page 13001]]
erosion from a landfill in which delisted waste has been disposed. The
USLE is used to calculate the amount of waste that will be eroded from
the landfill. In addition, the size of the landfill is computed using
the waste volume estimate provided by the petitioner. The volume of
surface water into which runoff occurs is determined by estimating the
expected size of the stream into which the soil is likely to enter. The
amount of soil delivered to surface water is calculated using a
sediment delivery ratio. The sediment delivery ratio determines the
percentage of eroded material that is delivered to surface water based
on the assumption that some eroded material will be redeposited between
the landfill and the surface water body. A distance of 100 meters (m)
to the nearest surface water body is assumed. The DRAS program as used
here is currently being revised to account for partitioning between
water and suspended solids when the eroded waste enters the stream.
Rainfall erosion factor values range from 20 to 550 per year. Values
greater than 300 occur in only a small proportion of the southeastern
United States. A value of 300 was chosen as a conservative estimate
ensuring that a reasonable worst-case scenario is provided for most
possible landfill locations. Soil erodibility factors range from 0.1 to
0.69 ton per acre. A value of 0.3 was selected for the analysis, which
is estimated to exceed 66% of all values assuming a normal
distribution. One month's worth of waste is assumed to be left
uncovered at any one time and thus would be readily transportable by
surface water runoff. Other variables used by the DRAS to evaluate
releases to surface waters employed conservative assumptions. DRAS
multiply the total annual mass of eroded material by the sediment
delivery ratio to determine the mass of soil and waste delivered to
surface water.
The predicted erosion capacity is gradually diluted as it mixes
with nearby surface waters. DRAS selects a representative volume or
flux rate of surface water based on stream order, which is a system of
taxonomy for streams and rivers. A stream that has no other streams
flowing into it is referred to as a first-order stream. Where two
first-order streams converge, a second-order stream is created. Where
two second-order streams converge, a third-order stream is created.
Data indicate that second-order streams have an estimated flow rate of
3.7 cubic feet per second. The second-order stream was selected for
analysis as the smallest stream capable of supporting recreational
fishing. Fifth-order streams were also chosen for analysis as the
smallest streams capable of serving as community water supplies. Fifth-
order stream flow is estimated to be 380 cubic feet per second.
6. By What Means May an Individual Be Exposed to the Proposed Exempted
Waste?
An exposure scenario is a combination of exposure pathways through
which a single receptor may be exposed to a waste constituent.
Receptors may be human or other animal in an ecosystem. There are many
potential exposure scenarios. The DRAS evaluated the risks of the
proposed waste associated with the exposure scenarios most likely to
occur as a result of releases from the waste management unit. Receptors
may come into contact with delisted waste constituent releases from a
waste management unit via two primary exposure routes, either (1)
directly via inhalation or ingestion of water or (2) indirectly via
subsequent ingestion of soil and foodstuffs (such as fish) that become
contaminated by waste constituents through the food chain. Receptors
may also be exposed to waste constituents released from a waste
management unit to surface media (via volatilization to air or via
windblown particulate matter) or to groundwater (via ingestion of
groundwater). The exposure scenarios assessed by DRAS are generally
conservative in nature and are not intended to be entirely
representative of actual scenarios at all sites. Rather, they are
intended to allow standardized and reproducible evaluation of risks
across most sites and land use areas. Conservatism is incorporated to
ensure protection of potential receptors not directly evaluated, such
as special subpopulations. The recommended exposure scenarios and
associated assumptions assessed by DRAS are reasonable and conservative
and they represent a scientifically sound approach that allows
protection of human health and the environment.
7. What Receptors Are Assessed for Risk From Exposure to the Proposed
Exempted Waste?
Adult and child residents are the two receptors evaluated in this
analysis. The adult resident exposure scenario is evaluated to account
for the combination of exposure pathways to which an adult receptor may
be exposed in an urban or rural (nonfarm) setting. The adult resident
is assumed to be exposed to waste constituents from an emission source
through the following exposure pathways:
(1) Direct inhalation of vapors and particles;
(2) Ingestion of fish;
(3) Ingestion of drinking water from surface water sources;
(4) Ingestion of drinking water from groundwater sources;
(5) Dermal absorption from groundwater sources via bathing;
(6) Inhalation from groundwater sources via showering
DRAS evaluates two exposure pathways for children: (1) dermal
absorption while bathing with potentially contaminated groundwater and
(2) the ingestion of soil containing contaminated particulates which
have been emitted from the landfill and deposited on the soil. Child
residents (1 to 6 years old) were not selected as receptors for the
groundwater ingestion and inhalation pathways, the surface water
pathways, or the direct air inhalation pathways because the adult
resident receptor scenario has been found to be protective of children
with regard to these pathways. There is no indication that children
consume more drinking water or inhale more air per unit of body weight,
factoring in the recognized exposure duration, than adults. Therefore,
average daily exposure normalized to body weight would be identical for
adults and children. Likewise, a child receptor was not included for
the freshwater fish ingestion pathway because there is no evidence that
children consume more fish relative to their body weight, factoring in
exposure duration, than do adults. The dermal absorption while bathing
with groundwater exposure pathway is evaluated differently for child
residents than it is for adult residents because of the following
considerations: (1) The ratio of exposed skin surface area to body
weight is slightly higher for children than for adults, resulting in a
slightly larger average daily exposure for children than for adults;
and (2) the exposure duration for such children is limited to 6 years,
thus lowering the lifetime average exposure to carcinogens. Typically,
the adult scenario is more protective with regard to carcinogens
(because of the longer exposure duration), and the child scenario is
more protective with regard to noncarcinogens (because of the greater
skin surface area to body weight ratio).
8. Where Does the DRAS Assume That Receptors Are Located When
Performing the Risk Evaluation?
The EPACMTP, a probabilistic groundwater fate and transport model,
was used to predict groundwater constituent concentrations at a
[[Page 13002]]
hypothetical receptor well located downgradient from a waste management
unit. This receptor well represents the POE. That is, the predicted
waste constituent concentration at the POE is used to assess the risk
of the proposed exempted waste. The distance to the well is based on
the results of the 1987 nationwide survey of landfills conducted by
EPA's Office of Solid Waste (OSW) which determined the distance to the
nearest drinking water well downgradient from municipal landfills. The
survey data are entered in the EPACMTP model as an empirical
distribution: minimum = 0 m, median = 427 m, and maximum = 1,610 m
(approximately 1 mile). In contrast to the 1990 Toxicity Characteristic
(TC) Rule (55 FR 11798), there is no requirement that the well lie
within the leachate plume.
For carcinogenic waste constituents, the exposure concentration is
defined as the maximum 30 year average receptor well concentration; for
noncarcinogens, the exposure concentration is taken to be the highest
receptor well concentration during the modeled 10,000 year period. A
10,000 year limit was imposed on the exposure period; that is, the
calculated exposure concentration is the peak or highest 30 year
average concentration occurring within 10,000 years following the
initial release from the waste management unit. The fate and transport
simulation within the CMTP provided a probability distribution of
receptor well concentrations as a function of expected leachate
concentration. Using the receptor well concentrations as a function of
the waste constituent concentration, the EPACMTP derived chemical-
specific dilution attenuation factors (DAFs) which convert a leachate
concentration in the landfill to a groundwater concentration at the
receptor well.
Human exposure routes for surface water include ingestion of
surface water used as drinking water and ingestion of fish from nearby
surface water bodies. For the surface water ingestion exposure route,
the surface water POE modeled is a fifth-order stream 100 m from the
waste management unit. Fifth-order streams were chosen for analysis
because EPA assumes that a fifth-order stream is the smallest stream
capable of serving as a community water supply. The assumption of a 100
m distance to the nearest surface water body is a conservative
assumption based on available data. An EPA survey of municipal landfill
facilities showed that 3.6 percent of the surveyed facilities are
located within 1 mile of a river or stream and that the average
distance from these facilities to the closest river or stream is 586 m
(1,921 feet). For the fish ingestion exposure route, a second-order
stream was chosen for analysis. This stream segment was determined to
be the smallest stream capable of supporting fisheries. The POE in the
surface water body for collection of fish is assumed to be 100 m
downgradient from the disposal facility. Human exposure to emissions of
windblown particulates from landfills and to emissions of volatiles
from landfills and surface impoundments is assessed by the DRAS. For
the air pathway, the DRAS assumes the POE is 305 m (1,000 feet)
downwind of the waste management unit.
9. How Does DRAS Determine Rates of Exposure?
The calculation of constituent-specific exposure rates for each
exposure pathway evaluated were based on:
(1) The estimated concentration in a given medium as calculated in
DRAS;
(2) The contact rate;
(3) Receptor body weight, and;
(4) The frequency and duration of exposure
This calculation is repeated for each constituent and for each
exposure pathway included in an exposure scenario. Exposure to
hazardous constituents is assumed to occur over a period of time. To
calculate an average exposure per unit of time, the DRAS divides the
total exposure by the time period. Exposures are intended to represent
reasonable maximum exposure (RME) estimates for each applicable
exposure route. The RME approach is intended to combine upper-bound and
mid-range exposure factors so that the result represents an exposure
scenario that is both protective and reasonable, not the worst possible
case.
10. What Rate of Contact With a Contaminated Media Does the DRAS Use?
The contact rate is the amount of contaminated medium contacted per
unit of time or event. Contact rates for subsistence food types (fish
for the fish ingestion pathway) are assumed to be 100 percent from the
hypothetical assessment area (surface water body). The following
sections describe exposure pathway-specific contact rates.
11. What Are the Contact Rates at Which Individuals Are Exposed to
Contaminated Media?
For groundwater and surface water ingestion, the intake rate is
assumed to be 2.0 liters per day (l/day), the average amount of water
that an adult ingests. This value, which is currently used to set
drinking water standards, is close to the current 90th percentile value
for adult drinking water ingestion (2.3 l/day) reported in the EPA
Exposure Factors Handbook. This value approximates the 8 glasses of
water per day historically recommended by health authorities. The
contact for the dermal exposure pathway is assumed to occur while
bathing with contaminated groundwater. In this analysis, the DRAS
assumes that the average adult resident is in contact with groundwater
during bathing for 0.25 hour per event and that the average child
resident is in contact with groundwater during bathing for 0.33 hour
per event, with one event per day. For dermal bathing exposure to
contaminated groundwater, the selected receptors are an adult and a
young child (1 to 6 years old). During bathing, generally all of the
skin surface is exposed to water. The total adult body surface area can
vary from about 17,000 to 23,000 square centimeters (cm2).
The EPA Exposure Factors Handbook (EFH) reports a value of 20,000
cm2 as the median value for adult skin surface area. A value
of 6,900 cm2 has been commonly used for a child receptor in
EPA risk assessments; this value is approximately the average of the
median values for male children aged 2 to 6. The EFH presents a range
of recommended values for estimates of the skin surface area of
children by age. The mean skin surface area at the median for boys and
girls 5 to 6 years of age is 0.79 square meters (m2) or
7,900 cm2. Given that the age for children is defined as 0
to 6 years (see EFH Section 3.3.4), a skin surface area value for ages
5 to 6 years would be a conservative estimate of skin surface area for
children. For calculation of dermal exposure to waste constituents, the
DRAS uses a value of 7,900 cm2 for the skin surface area of
children and a value of 20,000 cm2 for the skin surface area
of adults.
For the groundwater pathway of inhalation exposure during
showering, the contact with water is assumed to occur principally in
the shower and in the bathroom. The DRAS analysis assumes that the
average adult resident spends 11.4 minutes per day in the shower and an
additional 48.6 minutes per day in the bathroom. Daily inhalation rates
vary depending on activity, gender, age, and so on. Citing a need for
additional research, the EFH does not recommend a reasonable upper-
bound inhalation rate value. The EFH recommended value for the average
inhalation rate is 15.2 cubic meters per day (m3) for males
and 11.3 m3 day for females. The EPA established an upper-
[[Page 13003]]
bound value for an individual's inhalation rate at 20 m3 day
which has been commonly used in past EPA risk assessments. This value
is used by the DRAS for assessment of inhalation exposure.
The DRAS assesses the ingestion of soil contaminated with air-
deposited particulates from a nearby landfill. The potential for
exposure to constituents via soil ingestion is greater for children
because they are more likely to ingest more soil than adults as a
result of behavioral patterns present during childhood. Therefore,
exposure to waste constituents through ingestion of contaminated soils
is evaluated for the child in a delisting risk assessment. The mean
soil ingestion values for children range from 39 to 271 milligrams per
day (mg/day), with an average of 146 mg/day for soil ingestion and 191
mg/day for soil and dust ingestion (see EPA EFH). Based on the EFH
statement that 200 mg/day may be used as a conservative estimate of the
mean, the DRAS uses 200 mg/day as the soil ingestion rate for children.
Fish consumption rates vary greatly, depending on geographic region
and social or cultural factors. The recommended value for fish
consumption for all fish is 0.28 grams of fish per kilogram body weight
per day for an average adult (see EPA EFH). This value equates with a
fish consumption rate of 20.1 grams per day (g/day) for all fish. The
DRAS estimated that an exposed individual eats 20 g of fish per day,
representing one 8-ounce serving of fish approximately once every 11
days.
12. At What Frequency Does the DRAS Assume That Receptors Are Exposed
to Contaminated Media?
An exposure frequency of 350 days per year is applied to all
exposure scenarios (see EPA EFH). Until better data become available,
the common assumption that residents take 2 weeks of vacation per year
is used to support a value of 15 days per year spent away from home,
leaving 350 days per year spent at home and susceptible to exposure.
13. For What Duration Does the DRAS Assume Receptors Are Exposed to
Contaminated Media?
The exposure duration reflects the length of time that an exposed
individual may be expected to reside near the constituent source. For
the adult resident, this value is taken to be 30 years, and for the
child resident, this value is taken to be 6 years (see EPA EFH). The
adult resident is assumed to live in one house for 30 years, the
approximate average of the 90th percentile residence times from two key
population mobility studies. For the child resident, the exposure
duration is assumed to be 6 years, the maximum age of the young child
receptor. For carcinogens, exposures are combined for children (6
years) and adults (24 years). For noncarcinogenic constituents, the
averaging time (AT) equals the exposure duration in years multiplied by
365 days per year. For an adult receptor, the exposure duration is 30
years, and for a child receptor, the exposure duration is 6 years. For
carcinogenic constituents, the AT has typically been 25,550 days, based
on a lifetime exposure of 70 years at 365 days per year. The life
expectancy value in the EFH is 75 years. Given this life expectancy
value, the AT for a delisting risk assessment is 27,375 days, based on
a lifetime exposure of 75 years at 365 days per year.
14. What Body Weights Are Assumed for Receptors in the DRAS Evaluation?
Risk Assessment Guidance for Superfund defines the body weight of
the receptor as either adult weight (70 kilograms (kg)) or child weight
(1 to 6 years, 15 kg). The EFH recommended value of 71.8 kg for an
adult differs from the 70-kg value commonly used in EPA risk
assessments. In keeping with the latest EFH recommendation, the DRAS
used a 72-kg adult weight and a 15-kg child weight for the proposed
delisting determination.
B. What Risk Assessment Methods Has the Agency Used in Previous
Delisting Determinations That Are Being Revised in This Proposal?
1. Introduction
The fate and transport of constituents in leachate from the bottom
of the waste unit through the unsaturated zone and to a drinking water
well in the saturated zone was previously estimated using the EPA
Composite Model for Landfill (EPACML) (See 55 FR 11798). The EPACML
accounts for:
One-dimensional steady and uniform advective flow;
Contaminant dispersion in the longitudinal, lateral, and vertical
directions;
Sorption.
However, advances in groundwater fate and transport have been made
in recent years and the Agency proposes the use of a more advanced
groundwater fate and transport model for RCRA exclusions.
2. What Fate and Transport Model Does the Agency Use in the DRAS for
Evaluating the Risks to Groundwater From the Proposed Exempted Waste?
The Agency proposes to use the EPACMTP in this delisting
determination. The EPACMTP considers the subsurface fate and transport
of chemical constituents. The EPACMTP is capable of simulating the fate
and transport of dissolved contaminants from a point of release at the
base of a waste management unit, through the unsaturated zone and
underlying groundwater, to a receptor well at an arbitrary downstream
location in the aquifer. The model accounts for the following
mechanisms affecting contaminant migration: transport by advection and
dispersion, retardation resulting from reversible linear or nonlinear
equilibrium adsorption onto the soil and aquifer solid phase, and
biochemical degradation processes.
3. Why Is the EPACMTP Fate and Transport Model an Improvement Over the
EPACML?
The modeling approach used for this proposed rulemaking includes
three major categories of enhancements over the EPACML. The
enhancements include:
(1) Incorporation of additional fate and transport processes (e.g.,
degradation of chemical constituents);
(2) Use of enhanced flow and transport solution algorithms and
techniques (e.g., three-dimensional transport) and;
(3) Revision of the probabilistic methodology (e.g., site-based
implementation of available input data).
A discussion of the key enhancements which have been implemented in the
EPACMTP is presented here and the details are provided in the proposed
1995 Hazardous Waste Identification Rule (HWIR) background documents
(60 FR 66344-December 21, 1995).
The EPACML was limited to conditions of uniform groundwater flow.
It could not handle accurately the conditions of significant
groundwater mounding and non-uniform groundwater flow due to a high
rate of infiltration from the waste units. These conditions increase
the transverse horizontal as well as the vertical spreading of a
contaminant plume. The EPACMTP accounts for these effects directly by
simulating groundwater flow in the vertical as well as horizontal
directions.
The EPACMTP can simulate fate and transport of metals, taking into
account geochemical influences on the mobility
[[Page 13004]]
of metals. The EPA's MINTEQA2 metals speciation model is used to
generate effective sorption isotherms for individual metals,
corresponding to a range of geochemical conditions. The transport
modules in EPACMTP have been enhanced to incorporate the nonlinear
MINTEQ sorption isotherms. This enhancement provides the model with
capability to simulate, in the unsaturated and in the saturated zones,
the impact of pH, leachate organic matter, natural organic matter, iron
hydroxide and the presence of other ions in the groundwater on the
mobility of metals. The saturated zone module implemented in the EPACML
was based on a Gaussian distribution of concentration of a chemical
constituent in the saturated zone. The module also used an
approximation to account for the initial mixing of the contaminant
entering at the water table underneath the waste unit. The approximate
nature of this mixing factor could sometimes lead to unrealistic values
of contaminant concentration in the groundwater close to the waste
unit, especially in cases of a high infiltration rate from the waste
unit. The enhanced model incorporates a direct linkage between the
unsaturated zone and saturated zone modules which overcomes these
limitations of the EPACML.
To enable a greater flexibility and range of conditions that can be
modeled, the analytical saturated zone transport module has been
replaced with a numerical module, based on the highly efficient state-
of-the-art Laplace Transform Galerkin (LTG) technique. The enhanced
module can simulate the anisotropic, non-uniform groundwater flow, and
transient, finite source, conditions. The latter requires the model to
calculate a maximum receptor well concentration over a finite time
horizon, rather than just the steady state concentration which was
calculated by the EPACML. The saturated zone modules have been
implemented to provide either a fully three-dimensional solution, or a
highly efficient quasi-3D solution. The latter has been implemented for
probabilistic applications and provides nearly the same accuracy as the
fully three dimensional option, but is more computationally efficient.
Both the unsaturated zone and the saturated zone transport modules can
accommodate the formation and the transport of parent as well as of the
transformation products.
A highly efficient semi-analytical unsaturated zone transport
module has been incorporated to handle the transport of metals in the
unsaturated zone and can use MINTEQA2 derived linear or nonlinear
sorption isotherms. Conventional numerical solution techniques are
inadequate to handle extremely nonlinear isotherms. An enhanced method-
of-characteristic based solution has been implemented which overcomes
these problems and thereby enables the simulation of metals transport
in the probabilistic framework. Non-linearity in the metals sorption
isotherms is primarily of concern at higher concentration values; for
low concentrations, the isotherms are linear or close to linear.
Because of the attenuation in the unsaturated zone, and the subsequent
dilution in the saturated zone, concentrations in the saturated zone
are usually low enough so that properly linearized isotherms are used
by the model in the saturated zone without significant errors.
The internal routines in the model which determine placement of the
receptor well relative to the areal extent of the contaminant plume
have been revised and enhanced to eliminate bias which was present in
the implementation in the EPACML. The calculation of the areal extent
of the plume has been revised to take into consideration the dimensions
of the waste unit. The logic for placing a receptor well inside the
plume limits has been improved to eliminate a bias towards larger waste
unit areas and to ensure that the placement of the well inside these
limits, for a given radial distance from the unit, is truly randomly
uniform. However, for this proposal, the closest drinking water well is
located anywhere on the downgradient side of the waste unit.
The data sources from which parameter distributions for nationwide
probabilistic assessments are obtained have been evaluated, and where
appropriate, have been revised to make use of the latest data available
for modeling. Leachate rates for Subtitle D waste units have been
revised using the latest version of the Hydrologic Evaluation of
Landfill Performance (HELP) model with the revised data inputs. Source
specific input parameters (e.g., waste unit area and volume) have been
developed for various different types of industrial waste units besides
landfills. Input values for the groundwater related parameters have
been revised to utilize information from a nationwide industry survey
of actual contaminated sites. The original version of the model was
implemented for probabilistic assessments assuming continuous source
(infinite source) conditions only. This methodology did not take into
account the finite volume and/or operational life of waste units. The
EPACMTP model has been implemented for probabilistic assessments of
either continuous source or finite source scenarios. In the latter
scenario, predicted groundwater impact is not only based on the
concentrations of contaminants in the leachate, but also on the amount
of constituent in the waste unit and/or the operational life of the
unit.
The landfill is taken to be filled to capacity and covered when
leaching begins. The time period during which the landfill is filled-
up, usually assumed to be 20 years, is considered to be small relative
to the time required to leach all of the constituent mass out of the
landfill. The model simulation results indicate that this assumption is
not unreasonable; the model calculated leaching duration is typically
several hundred years. The leachate flux, or infiltration rate, is
determined using the HELP model. The net infiltration rate is
calculated using a water balance approach, which considers
precipitation, evapo-transpiration, and surface run-off. The HELP model
was used to calculate landfill infiltration rates for a representative
Subtitle D landfill with 2-foot earthen cover, and no liner or leachate
collection system, using climatic data from 97 climatic stations
located throughout the US. These correspond to the reasonable worst
case assumptions as explained in the HWIR Risk Assessment Background
Document for the HWIR proposed notice (60 FR 66344--December 21, 1995).
Additional details on the methodologies used by the EPACMTP to derive
DAFs for waste constituents modeled for the landfill scenario are
presented in the Background Documents for the proposed HWIR docket (60
FR 66344--December 21, 1995). The fraction of waste in the landfill is
assigned a uniform distribution with lower and upper limits of 0.036
and 1.0, respectively, based on analysis of waste composition in
Subtitle D landfills. The lower bound assures that the waste unit will
always contains a minimum amount of the waste of concern. The waste
density is assigned a value based on reported densities of hazardous
waste, and varies between 0.7 and 2.1 grams per cubic centimeter (g/
cm[bs]3[bs]).
The area of the surface impoundment and the impoundment depth used
by the EPACMTP are obtained from the OSW Subtitle D Industrial Survey
and were entered into the probabilistic analyses as distributions. The
sediment layer at the base of the impoundment is taken to be 2 feet
thick, and have an effective equivalent saturated conductivity of
10-7 centimeters per second (cm/s). These values were
selected in recognition of the fact that
[[Page 13005]]
most non-hazardous waste surface impoundments do have some kind of
liners in place. Additional details on the methodologies used by the
EPACMTP to derive DAFs for waste constituents modeled for the surface
impoundment waste management scenario are presented in the Background
Documents for the 1995 proposed HWIR docket (60 FR 66344--December 21,
1995).
4. Has the EPACMTP Methodology Been Formally Reviewed?
The Science Advisory Board (SAB), a public advisory group that
provides information and advice to the EPA, reviewed the EPACMTP model
as part of a continuing effort to provide improvements in the
development and external peer review of environmental regulatory
models. Overall, the SAB commended the Agency for making significant
enhancements to the EPACMTP's predecessor (EPACML) and for responding
to previous SAB suggestions. The SAB also concluded that the
mathematical formulation incorporating transformation or degradation
products into the model appeared to be correct and that the site-based
approach using hydrogeologic regions is superior to the previous
approach used in EPACML. The model underwent public comment during the
1995 proposed HWIR (60 FR 66344--December 21, 1995).
5. Has the Agency Modified the EPACMTP as Utilized in the HWIR
Proposal?
The EPACMTP, as developed for HWIR, determined the DAF using a
probabilistic approach that selected, at random, a waste volume from a
range of waste volumes identified in EPA's 1987 Subtitle D landfill
survey. In delisting determinations, the waste volume of the petitioner
is known. Therefore, application of EPACMTP to the delisting program
has been modified to evaluate the specific waste volume. The Agency
modified the DAFs determined under the HWIR proposal to account for a
known waste volume. To generate waste volume-specific DAFs, EPA
developed ``scaling factors'' to modify DAFs developed for HWIR (based
on the entire range of disposal unit areas) to DAFs for delisting waste
volumes. This was accomplished by computing a 90th percentile DAF for a
conservative chemical for 10 specific waste volumes (ranging from 1,000
cu. yds. to 300,000 cu. yds.) for each waste management scenario
(landfill and surface impoundment). The Agency assumed that DAFs for a
specific waste volume are linearly related to DAFs developed by EPACMTP
for the HWIR. DAF scaling factors were computed for the ten increment
waste volumes. Using these ten scaling factor DAFs, regression
equations were developed for each waste management scenario to provide
a continuum of DAF scaling factors as a function of waste volume.
The regression equations are coded into the DRAS program which then
automatically adjusts the DAF for the waste volume of the petitioner.
The method used to verify the scaling factor approach is presented in
Application of EPACMTP to Region 6 delisting Program: Development of
Volume-adjusted Dilution Attenuation Factors. For the landfill waste
management scenario, the DAF scaling factors ranged from 9.5 for 10,000
cu. yard to approximately 1.0 for waste volumes greater than 200,000
cu. yards. Therefore, for solid waste volumes greater than 200,000 cu.
yds., the waste volume-specific DAF is the same as the DAF computed for
the proposed HWIR. The regression equation that can be used to
determine the DAF scaling factor (DSF) as a function of waste volume
(in cubic yards) for the landfill waste management unit is: DSF =
6152.7 x (waste volume)-\0.7135\. The correlation
coefficient of this regression equation is 0.99, indicating a good fit
of this line to the data points. DAF scaling factors for surface
impoundment waste volumes ranged from 2.4 for 2,000 cu. yards to
approximately 1.0 for 100,000 cu. yds. For liquid waste volumes greater
than 200,000 cu. yds., the waste volume-specific DAF is the same as the
DAF computed for the proposed HWIR. The regression equation for DSF as
a function of waste volume for surface impoundment wastes is: DSF =
14.2 x (waste volume)-\0.2288\. The correlation coefficient
of this regression equation is also 0.99, indicating an extremely good
fit of this line to the data points.
V. Evaluation of This Petition
A. What Other Factors Did EPA Consider in Its Evaluation?
We also consider the applicability of ground-water monitoring data
during the evaluation of delisting petitions where the waste in
question is or has ever been placed on land. In this case, the waste
has been placed directly on soil or in contact with underlying clayey
sand and limestone bedrock. A total of three groundwater sampling
events has been conducted at the site from monitoring wells around the
existing drying beds and basins which contain the waste and submitted
to the Agency as part of the petition. Historical data showed sporadic
detection of four inorganic constituents in the groundwater and
indicated that the drying beds and basins waste was a possible source.
However, a confirmation groundwater sampling event utilizing a more
sophisticated EPA recommended sampling technique could not establish
that hazardous substances were currently leaching from the drying beds
and basins sludge as well as associated contaminated soil at levels
exceeding those predicted by the EPACMTP model in the DRAS program. The
evaluation was based on a statistical analysis conducted in accordance
with Statistical Analysis of Ground-Water Monitoring Data at RCRA
Facilities--Interim Final Guidance, EPA, April 1989 and Statistical
Analysis of Ground-Water Monitoring Data at RCRA Facilities--Addendum
to Interim Final Guidance, EPA, July 1992. Leachate analysis of sludge
samples generally supported the conclusion that the beds and basins
sludge was not currently a source of groundwater contamination above
health-based levels.
Specifically, chromium, lead, mercury and nickel were sporadically
detected in groundwater. However, the sludge did not appear to be
leaching these constituents to groundwater. Chromium, lead, and mercury
are present in background samples. The highest concentration of these
constituents were found in a single sample described as ``brown,
turbid.'' None of them were detected in the filtered portion of that
same sample. Nickel contamination could not be attributed to the sludge
and was detected in only one quarterly sampling event. Furthermore,
using low flow method in a confirmatory sampling event to account for
turbidity, except for mercury which was slightly above the health base
level, nickel was not detected and chromium and lead were detected
below the level of concern. Therefore, the analytical results of
groundwater show that elevated levels of mercury, nickel, chromium and
lead historically detected in the groundwater at the site are
attributable to naturally-occurring trace elements in fine sediments.
B. What Did EPA Conclude About GE's Analysis?
The total cumulative risk posed by the waste, is approximately 3.66
x 10-\6\. EPA believes that this risk is acceptable because
the value is within a generally acceptable range of 1 x
10-\4\ to 1 x 10-\6\ and the estimated risk is
associated with a single contaminant. Specifically, ingestion of
carcinogenic arsenic in groundwater contributes 3.66 x
10-\6\; the surface water pathway contributes 3.11 x
10-\9\. Cadmium, the other
[[Page 13006]]
contributor to the total risk and included only as a detection limit,
has no groundwater ingestion risk and its surface water pathway
contributes only 5.51 x 10-\15\ to the total level of risk.
After reviewing GE's processes, the EPA concludes that (1)
hazardous constituents of concern are present in GE's waste, but not at
levels which are likely to pose a threat to human health and the
environment when placed in a solid waste landfill; and (2) the
petitioned waste does not exhibit any of the characteristics of
ignitability, corrosivity, or reactivity. See 40 CFR 261.21, 261.22,
and 261.23, respectively.
C. What is EPA's Evaluation of This Delisting Petition?
The descriptions of the GE hazardous waste process and analytical
characterization, with the proposed verification testing requirements
(as discussed later in this document), provide a reasonable basis for
EPA to grant the exclusion.
The Agency has reviewed the sampling procedures used by GE and have
determined they satisfy EPA criteria for collecting representative
samples of constituent concentrations in the wastewater treatment
sludge.
EPA believes the data submitted in support of the petition show
that GE's waste will not pose a threat when disposed of in a Subtitle D
landfill regulated by a state. The Agency therefore, proposes to grant
GE an exclusion for its WWTP sludge.
If EPA finalizes the proposed rule, the Agency will no longer
regulate the petitioned waste under 40 CFR parts 262 through 268 and
the permitting standards of part 270.
VI. Conditions for Exclusion
A. What Are the Maximum Allowable Concentrations of Hazardous
Constituents in the Waste?
Table 2 below summarizes maximum observed TCLP concentrations in
GE's waste, maximum allowable leachate levels for GE's waste, and the
level of regulatory concern at the point of exposure for groundwater.
The EPA calculated delisting levels for all constituents detected.
Maximum allowable leachate concentrations (expressed as a result of
the TCLP test) were calculated for all constituents for which leachate
was analyzed. The allowable leachate concentrations were derived from
the health-based calculation within the DRAS program. Maximum allowable
leachate levels were also derived from MCLs, SDWA Treatment Technique
(TT) action levels, or toxicity characteristic levels from 40 CFR
261.24 if they resulted in a more conservative delisting level. The
maximum allowable point of exposure groundwater concentrations
correspond to the lesser of the health-based values calculated within
the DRAS program or the MCLs or TT action levels.
A statistical review of some of the data indicates that the maximum
values used in the modeling and risk estimation correspond to a very
high confidence interval. Assuming that the distribution of the data is
adequately defined, future samples are likely to exhibit concentrations
which are less than the maximum values used in this evaluation. All of
the maximum waste concentrations observed are less than the
corresponding delisting levels assigned.
Table 2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Maximum observed \1\ leachate concentration (mg/l TCLP) Maximum
------------------------------------------------------------------ Maximum allowable
allowable point of Maximum
leachate exposure allowable
Sludge drying beds Sludge SI basins concentration concentration TCLP base on
(mg/l TCLP) (mg/l in MCL mg/l
groundwater)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Arsenic................................ 0.0221 ND(0.1) 0.0604 0.604 6.19
Barium................................. 0.432 0.716 472 \2\358 359
Cadmium................................ ND ND(0.01) 3.63 \2\0.965 0.967
Chromium............................... 0.157 ND(0.01) 1400000 \2\2480 2480
Lead................................... ND ND(0.085) 484 483 484
Mercury................................ ND ND(0.0002) 0.219 \2\0.960 0.961
Nickel................................. 0.0214 ND(0.04) 182 182 ..............
Selenium............................... ND ND(0.195) 14 \2\0.748 3.74
Silver................................. ND ND(0.01) 24.8 24.8 ..............
Cyanide................................ ND ND(0.01) 87.1 \2\23.2 23.2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: ND=Not Detected (Detection Limit).
J=value is an estimated quantity.
\1\These levels represent the highest constituent concentration found in any one sample, not necessarily the specific levels found in one sample.
\2\The concentration is based on the MCL or TT action level.
In addition to the delisting values in the table, several delisting
levels based on total concentrations were also established for GE's
waste. Table 3 below summarizes maximum observed total concentrations
in GE's waste, maximum allowable total levels for GE's waste. In all
cases, the observed levels were below allowable levels.
Table 3
----------------------------------------------------------------------------------------------------------------
Maximum observed total concentration (mg/kg) Maximum
------------------------------------------------------------------ allowable total
concentration
Sludge drying beds Sludge SI basins Soil around basins mg/kg
----------------------------------------------------------------------------------------------------------------
Arsenic..................... 17.4J 27.4 91.0 91000
Barium...................... 21.1 38.6 140 20600000
Cadmium..................... ND 1.2 3.0 771000
[[Page 13007]]
Chromium.................... 5360 8400 4370 2310000000
Lead........................ R 677J 15.5/94.3J 541000
Mercury..................... 1.1J 1.6 0.49 80
Nickel...................... 10.8/43.3J 43.5/94J 64.4J 30800000
Selenium.................... 0.30J 0.66 0.55/0.61J 7710000
Silver...................... 26.4J 46.5 22.1 7710000
Cyanide..................... R ND ND 30800000
----------------------------------------------------------------------------------------------------------------
Note: ND=Not Detected (Detection Limit).
J=value is an estimated quantity.
R=rejected.
B. What Are the Conditions of the Exclusion?
The proposed exclusion only applies to the approximately five to
fifteen thousand cubic yards of sludge and contaminated soil described
in the petition. Any amount exceeding this volume cannot be considered
delisted under this exclusion. Furthermore, GE must dispose of this
sludge in a Subtitle D landfill which is permitted, licensed, or
registered by a state to manage industrial waste.
GE must also complete additional verification sampling in order to
ensure that the landfilled sludge meets delisting requirements. Each
unit shall at a minimum be divided into four quadrants and a boring
drilled at the center or an identified area of concern within each
quadrant. A composite sample comprising the vertical extent of the
sludge at each individual boring location is to be collected within the
sludge areas of the two drying beds and the two basins. Surface
composite samples using the same number of quadrant above shall be
collected for the sludge in the two basins and the contaminated soil in
the vicinity of the basins. The 102,400 square foot grid surrounding
the basins could stake on an 160-foot interval for a square grid area
of approximately 25,600 square feet (a total of four square grid). A
soil boring shall be installed at the center of each square grid for a
total of 4 soil borings. Boring samples shall be collected at three
depth levels (top, middle and bottom) for a total of three samples at
each boring location. A total of 40 samples is expected from the drying
beds, the basins and the area surrounding the basins. QA/QC protocols
would remain as spelled out in the petition. The samples are to be
analyzed for TCLP metals that includes arsenic, barium, cadmium,
chromium and nickel.
If, anytime after disposal of the delisted waste, GE possesses or
is otherwise made aware of any environmental or waste data (including
but not limited to leachate data or groundwater monitoring data) or any
other data relevant to the delisted waste indicating that any
constituent identified in section VI.A. is at a level higher than the
delisting level established in section VI.A. or is at a level in
groundwater that exceeds the point of exposure concentration
established in section VI.A., then GE must report such data, in
writing, to the Director of the Division of Environmental Planning and
Protection within 10 days of first possessing or being made aware of
that data.
Based on any information provided by GE and any other information
received from any source, the Director of the Division of Environmental
Planning and Protection will make a determination as to whether the
reported information requires GE to take action to protect human health
or the environment. Further action may include suspending, or revoking
the exclusion, or other appropriate response necessary to protect human
health and the environment.
C. What Happens if GE Fails To Meet the Conditions of the Exclusion?
If GE violates the terms and conditions established in the
exclusion, the Agency may start procedures to withdraw the exclusion.
The EPA has the authority under RCRA and the Administrative
Procedures Act, 5 U.S.C. 551 (1978) et seq. (APA), to reopen a
delisting decision if we receive new information indicating that the
conditions of this exclusion have been violated.
If the Director of the Division of Environmental Planning and
Protection determines that information reported by GE as described in
section VI.B., or information received from any other source, does
require GE to take action the Director of the Division of Environmental
Planning and Protection will notify GE in writing of the actions the
Director of the Division of Environmental Planning and Protection
believes are necessary to protect human health and the environment. The
notice shall include a statement of the proposed action and a statement
providing GE with an opportunity to present information as to why the
proposed action is not necessary or to suggest an alternative action.
GE shall have 10 days from the date of the Director's notice or such
other time period as established by EPA to present the information.
If after 10 days, GE presents no further information, the Director
of the Division of Environmental Planning and Protection will issue a
final written determination describing the actions that are necessary
to protect human health or the environment. Any required action
described in the Director's determination shall become effective
immediately, unless the Director of the Division of Environmental
Planning and Protection provides otherwise.
VII. Regulatory Impact
Under Executive Order 12866, EPA must conduct an ``assessment of
the potential costs and benefits'' for all ``significant'' regulatory
actions.
The proposal to grant an exclusion is not significant, since its
effect, if promulgated, would be to reduce the overall costs and
economic impact of EPA's hazardous waste management regulations. This
reduction would be achieved by excluding waste generated at a specific
facility from EPA's lists of hazardous wastes, thus enabling a facility
to manage its waste as nonhazardous.
Because there is no additional impact from today's proposed rule,
this
[[Page 13008]]
proposal would not be a significant regulation, and no cost/benefit
assessment is required. The Office of Management and Budget (OMB) has
also exempted this rule from the requirement for OMB review under
section (6) of Executive Order 12866.
VIII. Regulatory Flexibility Act
Under the Regulatory Flexibility Act, 5 U.S.C. 601-612, whenever an
agency is required to publish a general notice of rulemaking for any
proposed or final rule, it must prepare and make available for public
comment a regulatory flexibility analysis which describes the impact of
the rule on small entities (that is, small businesses, small
organizations, and small governmental jurisdictions). No regulatory
flexibility analysis is required, however, if the Administrator or
delegated representative certifies that the rule will not have any
impact on small entities.
This rule, if promulgated, will not have an adverse economic impact
on small entities since its effect would be to reduce the overall costs
of EPA's hazardous waste regulations and would be limited to one
facility. Accordingly, the Agency certifies that this proposed
regulation, if promulgated, will not have a significant economic impact
on a substantial number of small entities. This regulation, therefore,
does not require a regulatory flexibility analysis.
IX. Paperwork Reduction Act
Information collection and record-keeping requirements associated
with this proposed rule have been approved by Office of Management of
Budget (OMB) under the provisions of the Paperwork Reduction Act of
1980 (Public Law 96-511, 44 U.S.C. 3501 et seq.) and have been assigned
OMB Control Number 2050-0053.
X. Unfunded Mandates Reform Act
Under section 202 of the Unfunded Mandates Reform Act of 1995
(UMRA), Public Law 104-4, which was signed into law on March 22, 1995,
EPA generally must prepare a written statement for rules with federal
mandates that may result in estimated costs to state, local, and tribal
governments in the aggregate, or to the private sector, of $100 million
or more in any one year.
When such a statement is required for EPA rules, under section 205
of the UMRA, EPA must identify and consider alternatives, including the
least costly, most cost-effective, or least burdensome alternative that
achieves the objectives of the rule. EPA must select that alternative,
unless the Administrator explains in the final rule why it was not
selected or it is inconsistent with law.
Before EPA establishes regulatory requirements that may
significantly or uniquely affect small governments, including tribal
governments, EPA must develop under section 203 of the UMRA a small
government agency plan. The plan must provide for notifying potentially
affected small governments, giving them meaningful and timely input in
the development of EPA regulatory proposals with significant federal
intergovernmental mandates, and informing, educating, and advising them
on compliance with the regulatory requirements.
The UMRA generally defines a federal mandate for regulatory
purposes as one that imposes an enforceable duty upon state, local,
tribal governments or the private sector estimated to cost $100 million
or more in any one year.
The EPA finds that today's delisting decision is deregulatory in
nature and does not impose any enforceable duty on any state, local, or
tribal governments or the private sector estimated to cost $100 million
or more in any one year. In addition, the proposed delisting decision
does not establish any regulatory requirements for small governments
and so does not require a small government agency plan under UMRA
section 203.
XI. Executive Order 12875
Under Executive Order 12875, EPA may not issue a regulation that is
not required by statute and that creates a mandate upon a state, local,
or tribal government, unless the federal government provides the funds
necessary to pay the direct compliance costs incurred by those
governments. If the mandate is unfunded, EPA must provide to OMB a
description of the extent of EPA's prior consultation with
representatives of affected state, local, and tribal governments; the
nature of their concerns; copies of written communications from the
governments; and a statement supporting the need to issue the
regulation. In addition, Executive Order 12875 requires EPA to develop
an effective process permitting elected officials and other
representatives of state, local, and tribal governments ``to provide
meaningful and timely input in the development of regulatory proposals
containing significant unfunded mandates.'' Today's rule does not
create a mandate on state, local or tribal governments. The rule does
not impose any enforceable duties on these entities. Accordingly, the
requirements of section 1(a) of Executive Order 12875 do not apply to
this rule.
XII. Executive Order 13045
Executive Order 13045 is entitled ``Protection of Children from
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
proposed rule is not subject to Executive Order 13045 because this is
not an economically significant regulatory action as defined by
Executive Order 12866.
XIII. Executive Order 13084
Under Executive Order 13084, EPA may not issue a regulation that is
not required by statute, that significantly affects or uniquely affects
that communities of Indian tribal governments, and that imposes
substantial direct compliance costs on those communities, unless the
Federal government provides the funds necessary to pay the direct
compliance costs incurred by the tribal governments.
If the mandate is unfunded, EPA must provide to OMB, in a
separately identified section of the preamble to the rule, a
description of the extent of EPA's prior consultation with
representatives of affected tribal governments, a summary of the nature
of their concerns, and a statement supporting the need to issue the
regulation.
In addition, Executive Order 13084 requires EPA to develop an
effective process permitting elected and other representatives of
Indian tribal governments ``to meaningful and timely input'' in the
development of regulatory policies on matters that significantly or
uniquely affect their communities of Indian tribal governments. This
action does not involve or impose any requirements that affect Indian
Tribes. Accordingly, the requirements of section 3(b) of Executive
Order 13084 do not apply to this rule.
XIV. Executive Order 13132
Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August
10, 1999), requires EPA to develop an accountable process to ensure
``meaningful and timely input by State
[[Page 13009]]
and local officials in the development of regulatory policies that have
federalism implications.'' ``Policies that have federalism
implications'' is defined in the Executive Order to include regulations
that have ``substantial direct effects on the States, on the
relationship between the national levels of government.''
Under section 6 of Executive Order 13132, EPA may not issue a
regulation that has federalism implications, that imposes substantial
direct compliance costs, and that is not required by statute, unless
the Federal government provides the funds necessary to pay the direct
compliance costs incurred by State and local governments or EPA
consults with State and local officials early in the process of
developing the proposed regulation. EPA also may not issue a regulation
that has federalism implication and that preempts State law, unless the
Agency consults with State and local officials early in the process of
developing the proposed regulation.
This proposed rule does not have federalism implications. It will
not have substantial direct effects on the States, on the relationship
between the national government and the States, or on the distribution
of power and responsibilities among the various levels of government,
as specified in the Executive Order 13132. Thus, the requirements of
section 6 of the Executive Order do not apply to this rule.
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 doing so would be
inconsistent with applicable law or otherwise impractical.
Voluntary consensus standards are technical standards (for example,
materials specifications, test methods, sampling procedures, business
practices, etc.) that are developed or adopted by voluntary consensus
standard bodies. Where EPA does not use available and potentially
applicable voluntary consensus standards, the Act requires that 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 proposed rule.
List of Subjects in 40 CFR Part 261
Environmental protection, Hazardous waste, Recycling, Reporting and
recordkeeping requirements.
Authority: Sec. 3001(f) RCRA, 42 U.S.C. 6921(f).
Dated: December 15, 2003.
Walter Mugdan,
Director, Division of Environmental Planning and Protection.
Editorial Note: This document was received in the Office of the
Federal Register on March 16, 2004.
For the reasons set out in the preamble, 40 CFR part 261 is
proposed to be amended as follows:
PART 261--IDENTIFICATION AND LISTING OF HAZARDOUS WASTE
1. The authority citation for part 261 continues to read as
follows:
Authority: 42 U.S.C. 6905, 6912(a), 6921, 6922, and 6938.
2. In Table 1 of appendix IX of part 261, add the following waste
stream in alphabetical order by facility to read as follows:
Appendix IX to Part 261--Wastes Excluded Under Sec. Sec. 260.20 and
260.22
Table 1.--Wastes Excluded From Non-Specific Sources
----------------------------------------------------------------------------------------------------------------
Facility Address Waste description
----------------------------------------------------------------------------------------------------------------
* * * * * * *
GE's Former RCA del Caribe................. Barceloneta Puerto Rico.................... Wastewater treatment
plant (WWTP) sludges
from chemical etching
operation. (EPA
Hazardous Waste No.
F006) and
contaminated soil
mixed with sludge.
This is a one-time
exclusion for a range
of 5,000 to15,000
cubic yards of WWTP
sludge. This
exclusion was
published on [insert
publication date of
the final rule].
1. Delisting Levels:
(A) The constituent
concentrations
measured in the TCLP
extract may not
exceed the following
levels (mg/L):
arsenic--0.0604;
barium--472; cadmium--
3.63; chromium--
1,400,000; lead--484;
mercury--0.219;
nickel--182;
selenium--14; silver--
24.8; and cyanide--
87.1
(B) The total
constituent
concentrations in any
sample may not exceed
the following levels
(mg/kg): arsenic--
91,000; barium--
20,600,000; cadmium--
771,000; chromium--
2,310,000,000; lead--
541,000; mercury--80;
nickel--30,800,000;
selenium--771,000;
silver--771,000; and
cyanide--30,800,000.
[[Page 13010]]
2. Verification
Sampling--For the two
drying beds and two
basins, composite
samples comprising
the vertical extent
at individual boring
location; for the
contaminated soil
around the basins;
boring samples at 3
different depth
levels (top, middle
and bottom) also at
individual boring
location, are to be
collected from four
different boring
locations or quadrant
within each of the
units and four
different square grid
areas within the soil
surrounding the
basins. Surface
composite samples
within each quadrant
and square grid shall
also be collected for
the sludge in the two
basins and the
contaminated soil in
the vicinity of the
basins. A total of
forty samples must be
collected as follows:
Sixteen boring
composite samples for
the drying beds and
basins, twelve
surface composite
samples for the
basins and
contaminated soil,
and twelve boring
samples for the soil
around the basins.
The samples are to be
analyzed for TCLP
metals that include
arsenic, barium,
cadmium, chromium and
nickel. The results
are to be compared to
the delisting levels
in Condition (1)(a).
Sludge from which
samples collected
exceed delisting
levels are not
delisted. Additional
sampling can be
conducted with the
approval of U.S. EPA
Region 2 in order to
isolate the sludge
which exceeds the
delisting levels from
sludge that meets the
delisting levels.
3. Reopener Language--
(a) If, anytime after
disposal of the
delisted waste, GE
possesses or is
otherwise made aware
of any data
(including but not
limited to leachate
data or groundwater
monitoring data) or
any other data
relevant to the
delisted waste
indicating that any
constituent
identified in
Condition (1) is at a
level higher than the
delisting level
established in
Condition (1), or is
at a level in the
groundwater at a
level exceeding the
point of exposure
groundwater levels
established in
section VI.A. of the
preamble, then GE
must report such
data, in writing, to
the Director of the
Division of
Environmental
Planning and
Protection within 10
days of first
possessing or being
made aware of that
data. (b) Based on
the information
described in
paragraph (a) and any
other information
received from any
source, the Director
will make a
preliminary
determination as to
whether the reported
information requires
GE to take action to
protect human health
or the environment.
Further action may
include suspending,
or revoking the
exclusion, or other
appropriate response
necessary to protect
human health and the
environment.
(c) If the Director of
the Division of
Environmental
Planning and
Protection determines
that the reported
information does
require action, the
Director of the
Division of
Environmental
Planning and
Protection will
notify GE in writing
of the actions the
Director believes are
necessary to protect
human health and the
environment. The
notice shall include
a statement of the
proposed action and a
statement providing
GE with an
opportunity to
present information
as to why the
proposed action is
not necessary or to
suggest an
alternative action.
GE shall have 10 days
from the date of the
Director's notice or
such other time
period as is
established by EPA to
present the
information.
(d) If after 10 days
GE presents no
further information,
the Director of the
Division of
Environmental
Planning and
Protection will issue
a final written
determination
describing the
actions that are
necessary to protect
human health or the
environment. Any
required action
described in the
Director's
determination shall
become effective
immediately, unless
the Director of the
Division of
Environmental
Planning and
Protection provides
otherwise.
4. Notifications--GE
must provide a one-
time written
notification to any
State Regulatory
Agency to which or
through which the
waste described above
will be transported
for disposal at least
60 days prior to the
commencement of such
activities. Failure
to provide such a
notification will
result in a violation
of the waste
exclusion and a
possible revocation
of the decision.
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[[Page 13011]]
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[FR Doc. 04-6216 Filed 3-18-04; 8:45 am]
BILLING CODE 6560-50-P