[Federal Register Volume 72, Number 24 (Tuesday, February 6, 2007)]
[Proposed Rules]
[Pages 5510-5550]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-1617]
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Part II
Environmental Protection Agency
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40 CFR Part 60
Standards of Performance for New Stationary Sources and Emission
Guidelines for Existing Sources: Hospital/Medical/Infectious Waste
Incinerators; Proposed Rule
Federal Register / Vol. 72, No. 24 / Tuesday, February 6, 2007 /
Proposed Rules
[[Page 5510]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 60
[EPA-HQ-OAR-2006-0534; FRL-8274-9]
RIN 2060-A004
Standards of Performance for New Stationary Sources and Emission
Guidelines for Existing Sources: Hospital/Medical/Infectious Waste
Incinerators
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: On September 15, 1997, EPA adopted new source performance
standards (NSPS) and emission guidelines for hospital/medical/
infectious waste incinerators (HMIWI). The NSPS and emission guidelines
were established under sections 111 and 129 of the Clean Air Act (CAA).
On November 14, 1997, the Sierra Club and the Natural Resources Defense
Council (Sierra Club) filed suit in the U.S. Court of Appeals for the
District of Columbia Circuit (the Court) challenging EPA's methodology
for adopting the regulations. On March 2, 1999, the Court issued its
opinion. The Court remanded the rule to EPA for further explanation of
the Agency's reasoning in determining the minimum regulatory ``floors''
for new and existing HMIWI. The Court did not vacate the regulations,
so the NSPS and emission guidelines remained in effect during the
remand and were fully implemented by September 2002. This action
provides EPA's proposed response to the questions raised in the Court's
remand.
Section 129(a)(5) of the CAA requires EPA to review and, if
appropriate, revise the NSPS and emission guidelines every 5 years. In
this action, EPA also is proposing our response to this 5-year review,
which would revise the emission limits in the NSPS and emission
guidelines to reflect the levels of performance actually achieved by
the emission controls installed to meet the emission limits set forth
in the September 15, 1997, NSPS and emission guidelines.
DATES: Comments. Comments must be received on or before April 9, 2007.
Under the Paperwork Reduction Act, comments on the information
collection provisions must be received by the Office of Management and
Budget (OMB) on or before March 8, 2007. Because of the need to resolve
the issues raised in this action in a timely manner, EPA will not grant
requests for extensions beyond these dates.
Public Hearing. If anyone contacts EPA by February 26, 2007
requesting to speak at a public hearing, EPA will hold a public hearing
on March 8, 2007. If you are interested in attending the public
hearing, contact Ms. Pamela Garrett at (919) 541-7966 to verify that a
hearing will be held.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2006-0534, by one of the following methods:
www.regulations.gov: Follow the on-line instructions for submitting
comments.
E-mail: Send your comments via electronic mail to [email protected], Attention Docket ID No. EPA-HQ-OAR-2006-0534.
Facsimile: Fax your comments to (202) 566-1741, Attention Docket ID
No. EPA-HQ-OAR-2006-0534.
Mail: Send your comments to: EPA Docket Center (EPA/DC),
Environmental Protection Agency, Mailcode 6102T, 1200 Pennsylvania
Ave., NW., Washington, DC 20460, Attention Docket ID No. EPA-HQ-OAR-
2006-0534.
Hand Delivery: Deliver your comments to: EPA Docket Center (EPA/
DC), EPA West Building, Room 3334, 1301 Constitution Ave., NW.,
Washington, DC 20460, Attention Docket ID No. EPA-HQ-OAR-2006-0534.
Such deliveries are accepted only during the normal hours of operation
(8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal
holidays), and special arrangements should be made for deliveries of
boxed information.
Instructions: Direct your comments to Docket ID No. EPA-HQ-OAR-
2006-0534. The EPA's policy is that all comments received will be
included in the public docket and may be made available online at
www.regulations.gov, including any personal information provided,
unless the comment includes information claimed to be Confidential
Business Information (CBI) or other information whose disclosure is
restricted by statute. Do not submit information that you consider to
be CBI or otherwise protected through www.regulations.gov or e-mail.
The www.regulations.gov Web site is an ``anonymous access'' system,
which means EPA will not know your identity or contact information
unless you provide it in the body of your comment. If you send an e-
mail comment directly to EPA without going through www.regulations.gov,
your e-mail address will be automatically captured and included as part
of the comment that is placed in the public docket and made available
on the Internet. If you submit an electronic comment, EPA recommends
that you include your name and other contact information in the body of
your comment and with any disk or CD-ROM you submit. If EPA cannot read
your comment due to technical difficulties and cannot contact you for
clarification, EPA may not be able to consider your comment. Electronic
files should avoid the use of special characters, any form of
encryption, and be free of any defects or viruses.
Public Hearing: If a public hearing is held, it will be held at
EPA's Campus located at 109 T.W. Alexander Drive in Research Triangle
Park, NC, or an alternate site nearby. Persons interested in presenting
oral testimony must contact Ms. Pamela Garrett at (919) 541-7966 at
least 2 days in advance of the hearing.
Docket: EPA has established a docket for this action under Docket
ID No. EPA-HQ-OAR-2006-0534 and Legacy Docket ID No. A-91-61. All
documents in the docket are listed in the www.regulations.gov index.
Although listed in the index, some information is not publicly
available, e.g., CBI or other information whose disclosure is
restricted by statute. Certain other material, such as copyrighted
material, will be publicly available only in hard copy form. Publicly
available docket materials are available either electronically at
www.regulations.gov or in hard copy at the EPA Docket Center EPA/DC,
EPA West, Room 3334, 1301 Constitution Ave., NW., Washington, DC. The
Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through
Friday, excluding legal holidays. The telephone number for the Public
Reading Room is (202) 566-1744, and the telephone number for the EPA
Docket Center is (202) 566-1742.
FOR FURTHER INFORMATION CONTACT: Ms. Mary Johnson, Energy Strategies
Group, Sector Policies and Programs Division (D243-01), Environmental
Protection Agency, Research Triangle Park, North Carolina 27711;
telephone number: (919) 541-5025; fax number: (919) 541-5450; e-mail
address: [email protected].
SUPPLEMENTARY INFORMATION: Organization of This Document. The following
outline is provided to aid in locating information in this preamble.
I. General Information
A. Does the proposed action apply to me?
B. What should I consider as I prepare my comments?
II. Background
III. Summary
A. Litigation and Proposed Remand Response
[[Page 5511]]
B. Proposed Amendments (CAA Section 129(a)(5) 5-Year Review)
IV. Rationale
A. Rationale for the Proposed Response to the Remand
B. Rationale for the Proposed Amendments (CAA Section 129(a)(5)
5-Year Review)
V. Impacts of the Proposed Action for Existing Units
A. What are the primary air impacts?
B. What are the water and solid waste impacts?
C. What are the energy impacts?
D. What are the secondary air impacts?
E. What are the cost and economic impacts?
VI. Impacts of the Proposed Action for New Units
VII. Relationship of the Proposed Action to Section 112(c)(6) of the
CAA
VIII. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review
B. Paperwork Reduction Act
C. Regulatory Flexibility Act
D. Unfunded Mandates Reform Act
E. Executive Order 13132: Federalism
F. Executive Order 13175: Consultation and Coordination with
Indian Tribal Governments
G. Executive Order 13045: Protection of Children from
Environmental Health and Safety Risks
H. Executive Order 13211: Actions That Significantly Affect
Energy Supply, Distribution or Use
I. National Technology Transfer Advancement Act
I. General Information
A. Does the proposed action apply to me?
Regulated Entities. Categories and entities potentially affected by
the proposed action are those which operate HMIWI. The NSPS and
emission guidelines for HMIWI affect the following categories of
sources:
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Examples of
Category NAICS Code potentially
regulated entities
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Industry..................................... 622110, 622310, 325411, 325412, 562213, Private hospitals,
611310. other health care
facilities,
commercial
research
laboratories,
commercial waste
disposal
companies, private
universities.
Federal Government........................... 622110, 541710, 928110...................... Federal hospitals,
other health care
facilities, public
health service,
armed services.
State/local/Tribal Government................ 622110, 562213, 611310...................... State/local
hospitals, other
health care
facilities, State/
local waste
disposal services,
State
universities.
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This table is not intended to be exhaustive, but rather provides a
guide for readers regarding entities likely to be affected by the
proposed action. To determine whether your facility would be affected
by the proposed action, you should examine the applicability criteria
in 40 CFR 60.50c of subpart Ec and 40 CFR 60.32e of subpart Ce. If you
have any questions regarding the applicability of the proposed action
to a particular entity, contact the person listed in the preceding FOR
FURTHER INFORMATION CONTACT section.
B. What should I consider as I prepare my comments?
1. Submitting CBI
Do not submit information that you consider to be CBI
electronically through www.regulations.gov or e-mail. Send or deliver
information identified as CBI to only the following address: Ms. Mary
Johnson, c/o OAQPS Document Control Officer (Room C404-02), U.S. EPA,
Research Triangle Park, NC 27711, Attention Docket ID No. EPA-HQ-OAR-
2006-0534. Clearly mark the part or all of the information that you
claim to be CBI. For CBI information in a disk or CD ROM that you mail
to EPA, mark the outside of the disk or CD ROM as CBI and then identify
electronically within the disk or CD ROM the specific information that
is claimed as CBI. In addition to one complete version of the comment
that includes information claimed as CBI, a copy of the comment that
does not contain the information claimed as CBI must be submitted for
inclusion in the public docket. Information marked as CBI will not be
disclosed except in accordance with procedures set forth in 40 CFR part
2.
If you have any questions about CBI or the procedures for claiming
CBI, please consult the person identified in the FOR FURTHER
INFORMATION CONTACT section.
2. Tips for Preparing Your Comments
When submitting comments, remember to:
a. Identify the rulemaking by docket number and other identifying
information (subject heading, Federal Register date and page number).
b. Follow directions. The EPA may ask you to respond to specific
questions or organize comments by referencing a Code of Federal
Regulations (CFR) part or section number.
c. Explain why you agree or disagree; suggest alternatives and
substitute language for your requested changes.
d. Describe any assumptions and provide any technical information
and/or data that you used.
e. If you estimate potential costs or burdens, explain how you
arrived at your estimate in sufficient detail to allow for it to be
reproduced.
f. Provide specific examples to illustrate your concerns, and
suggest alternatives.
g. Explain your views as clearly as possible, avoiding the use of
profanity or personal threats.
h. Make sure to submit your comments by the comment period deadline
identified in the preceding section titled DATES.
3. Docket
The docket number for the proposed action regarding the HMIWI NSPS
(40 CFR part 60, subpart Ec) and emission guidelines (40 CFR part 60,
subpart Ce) is Docket ID No. EPA-HQ-OAR-2006-0534.
4. Worldwide Web (WWW)
In addition to being available in the docket, an electronic copy of
this proposed action is available on the WWW through the Technology
Transfer Network Web site (TTN Web). Following signature, EPA posted a
copy of the proposed action on the TTN's policy and guidance page for
newly proposed or promulgated rules at http://www.epa.gov/ttn/oarpg.
The TTN provides information and technology exchange in various areas
of air pollution control.
II. Background
Section 129 of the CAA, entitled ``Solid Waste Combustion,''
requires EPA to develop and adopt NSPS and emission guidelines for
solid waste incineration units pursuant to CAA sections 111 and 129.
Sections 111(b) and 129(a) of the CAA (NSPS program) address emissions
from new HMIWI units, and CAA sections 111(d) and 129(b) (emission
guidelines program) address emissions from existing HMIWI units. The
NSPS are directly enforceable Federal regulations. The emission
guidelines are not directly enforceable but, rather, are implemented by
State air pollution control agencies through sections 111(d)/129 State
plans.
An HMIWI is defined as any device used to burn hospital waste or
medical/
[[Page 5512]]
infectious waste. Hospital waste means discards generated at a
hospital, and medical/infectious waste means any waste generated in the
diagnosis, treatment, or immunization of human beings or animals, in
research pertaining thereto, or in the production or testing of
biologicals (e.g., vaccines, cultures, blood or blood products, human
pathological waste, sharps). Hospital/medical/infectious waste does not
include household waste, hazardous waste, or human and animal remains
not generated as medical waste. An HMIWI typically is a small, dual-
chamber incinerator that burns about 800 pounds per hour (lb/hr) of
waste. Smaller units burn as little as 13 lb/hr while larger units burn
as much as 3,700 lb/hr.
Incineration of hospital/medical/infectious waste causes the
release of a wide array of air pollutants, some of which exist in the
waste feed material and are released unchanged during combustion, and
some of which are generated as a result of the combustion process
itself. These pollutants include particulate matter (PM); heavy metals,
including lead (Pb), cadmium (Cd), and mercury (Hg); toxic organics,
including chlorinated dibenzo-p-dioxins/dibenzofurans (CDD/CDF); carbon
monoxide (CO); nitrogen oxides (NOX); and acid gases,
including hydrogen chloride (HCl) and sulfur dioxide (SO2).
In addition to the use of good combustion control practices, HMIWI
units are typically controlled by wet scrubbers or dry sorbent
injection fabric filters (dry scrubbers).
Combustion control includes the proper design, construction,
operation, and maintenance of HMIWI to destroy or prevent the formation
of air pollutants prior to their release to the atmosphere. Test data
indicate that as secondary chamber residence time and temperature
increase, emissions decrease. Combustion control is most effective in
reducing CDD/CDF, PM, and CO emissions. The 0.25-second combustion
level includes a minimum secondary chamber temperature of 1700 [deg]F
and a 0.25-second secondary chamber residence time. These combustion
conditions are typical of older HMIWI. The 1-second combustion level
includes a minimum secondary chamber temperature of 1700 [deg]F and
residence time of 1 second. These combustion conditions are typical of
newer HMIWI. Compared to 0.25-second combustion, 1-second combustion
will achieve substantial reductions in CDD/CDF and CO emissions, and
will provide some control of PM, but will not reduce emissions of acid
gases (HCl and SO2), NOX, or metals (Pb, Cd, and
Hg). The 2-second combustion level includes a minimum secondary chamber
temperature of 1800 [deg]F and residence time of 2 seconds. These
combustion conditions will provide additional control of CDD/CDF, CO,
and PM, but will not reduce emissions of acid gases (HCl and
SO2), NOX, or metals (Pb, Cd, and Hg). The 2-
second combustion conditions are considered to be the best level of
combustion control (i.e., good combustion) that is applied to HMIWI.
Wet scrubbers and dry scrubbers provide control of PM, CDD/CDF, HCl,
and metals, but do not influence CO, SO2 (at the low
concentrations emitted by HMIWI units), or NOX; in fact,
there are no technologies currently used by HMIWI that will
consistently reduce SO2 or NOX emissions. (See
Legacy Docket ID No. A-91-61, item II-A-111; 60 FR 10669, 10671-10677;
and 61 FR 31742-31743.)
On September 15, 1997, EPA adopted NSPS (40 CFR part 60, subpart
Ec) and emission guidelines (40 CFR part 60, subpart Ce) for entities
which operate HMIWI. The NSPS and emission guidelines are designed to
reduce air pollution emitted from new and existing HMIWI, including
HCl, CO, Pb, Cd, Hg, PM, CDD/CDF (total, or 2,3,7,8-tetrachlorinated
dibenzo-p-dioxin toxic equivalent (TEQ)), NOX, SO2, and
opacity. The NSPS apply to HMIWI for which construction began after
June 20, 1996, or for which modification began after March 16, 1998.
The NSPS became effective on March 16, 1998, and its requirements apply
as of that date or at start-up of a HMIWI unit, whichever is later. The
emission guidelines apply to HMIWI for which construction began on or
before June 20, 1996, and required compliance by September 2002.
CAA section 129 requires EPA to establish technology-based emission
standards that reflect levels of control EPA determines are achievable
for new and existing units, after considering costs, non-air quality
health and environmental impacts, and energy requirements associated
with the implementation of the standards.
In setting forth the methodology EPA must use to establish the
technology-based performance standards and emissions guidelines, CAA
section 129(a)(2) provides that standards ``applicable to solid waste
incineration units promulgated under section 111 and this section shall
reflect the maximum degree of reduction in emissions of [certain listed
air pollutants] that the Administrator, taking into consideration the
cost of achieving such emission reduction, and any non-air quality
health and environmental impacts and energy requirements, determines is
achievable for new and existing units in each category.'' This level of
control is referred to as a maximum achievable control technology, or
MACT standard.
In promulgating a MACT standard, EPA must first calculate the
minimum stringency levels for new and existing solid waste incineration
units in a category, generally based on levels of emissions control
achieved or required to be achieved by the subject units. The minimum
level of stringency is called the MACT floor, and CAA section 129(a)(2)
provides that the ``degree of reduction in emissions that is deemed
achievable for new units in a category shall not be less stringent than
the emissions control that is achieved in practice by the best
controlled similar unit, as determined by the Administrator. Emissions
standards for existing units in a category may be less stringent than
standards for new units in the same category but shall not be less
stringent than the average emissions limitation achieved by the best
performing 12 percent of units in the category.''
The minimum stringency requirements form the first and least
stringent regulatory option EPA must consider in the determination of
MACT for a source category. EPA must also determine whether to control
emissions ``beyond the floor,'' after considering the costs, non-air
quality health and environmental impacts, and energy requirements of
such more stringent control. These are the two steps EPA took in the
1997 HMIWI rulemaking. Finally, every 5 years after adopting a MACT
standard under section 129, CAA section 129(a)(5) requires EPA to
review and, if appropriate, revise the incinerator standards. In
addition to responding to the Court's remand in Sierra Club v. EPA, 167
F.3d 658 (D.C. Cir. 1999), this proposed action includes our first set
of proposed revisions to the HMIWI standards, also known as the 5-year
review.
III. Summary
A. Litigation and Proposed Remand Response
1. What was EPA's general methodology for determining MACT?
The methodology used to determine MACT is similar for source
categories under sections 112 and 129 of the CAA. However, because each
source category is unique and the data available to determine the
performance capabilities of technology can vary from one source
category to another, the basic methodology must be adapted to fit the
[[Page 5513]]
source category in question. As the Court pointed out in the HMIWI
litigation, it ``generally defer[s] to an agency's decision to proceed
on the basis of imperfect scientific information, rather than to
`invest the resources to conduct the perfect study.' '' Sierra Club v.
EPA, 167 F.3d at 662.
In general, all MACT analyses involve an assessment of the air
pollution control systems or technologies used by the better performing
units in a source category. The technology assessment can be based
solely on actual emissions data, on knowledge of the air pollution
control in place in combination with actual emissions data, or on State
regulatory requirements, which give an indication of the actual
performance of the regulated units. For each source category, the
assessment of the technology involves a review of actual emissions data
with an appropriate accounting for emissions variability. Where there
is more than one method or technology to control emissions, the
analysis results in a series of potential regulations (called
regulatory options), one of which is selected as MACT.
The first regulatory option considered by EPA must be at least as
stringent as the CAA's minimum stringency requirements. However, MACT
is not necessarily the least stringent regulatory option. EPA must
examine more stringent regulatory options to determine MACT. Unlike the
minimum stringency requirements, EPA must consider various impacts of
the more stringent regulatory options in determining MACT. Only if the
more stringent regulatory options are considered to have unreasonable
impacts does EPA select the first ``floor-based'' regulatory option as
MACT.
As stated earlier, the CAA requires that MACT for new sources be no
less stringent than the emissions control achieved in practice by the
best controlled similar unit. After EPA's assessment of technology, EPA
determines the best control currently in use for a given pollutant and
establishes one potential regulatory option at the emission level
achievable by that control. More stringent potential regulatory options
might reflect controls used on other sources that could be applied to
the source category in question.
For existing sources, the CAA requires that MACT be no less
stringent than the average emissions limitation achieved by the best
performing 12 percent of units in a source category. EPA must determine
some measure of the average emissions limitation achieved by the best
performing 12 percent of units to form the least stringent regulatory
option. Sometimes, a direct calculation of the actual emissions values
from the best performing 12 percent of sources provides the basis for
this regulatory option. More often, EPA determines the technology used
by the average source in the best performing 12 percent of sources and
establishes the floor based on the technology assessment for that
average source. More stringent regulatory options reflect other
technologies capable of achieving better performance.
2. What was EPA's methodology in the 1997 HMIWI rulemaking?
On February 27, 1995, EPA published a notice of proposed rulemaking
regarding emissions standards for HMIWI units (60 FR 10654). The
proposal was the result of several years of reviewing available
information. During the public comment period for the proposal, EPA
received over 700 letters, some of which contained new information or
indicated that the commenters were in the process of gathering more
information for EPA to consider. The new information led EPA to
consider the need for numerous changes to the proposed rule, and on
June 20, 1996, the Agency published a re-proposal (61 FR 31736).
Following an additional public comment period, EPA published the final
rule on September 15, 1997 (62 FR 48348).
During the data-gathering phase of developing the 1995 proposal,
EPA found it difficult to obtain an accurate count of the thousands of
HMIWI units nationwide, or to find HMIWI units with add-on air
pollution control systems in place. A few HMIWI units with combustion
control were tested to assess performance of combustion control in
reducing emissions. One unit with a wet scrubber, and a few units with
dry scrubbing systems were tested to determine performance capabilities
of add-on controls. (See 61 FR 31738.)
Altogether, data were available from only 7 out of the estimated
then-operating 3,700 existing HMIWI units (60 FR 10674). Because EPA
was under a court-ordered deadline to propose and adopt standards for
HMIWI that did not provide sufficient time to collect more actual
emissions data (see consent decree entered in Sierra Club v. EPA, Nos.
CV-92-2093 and CV-93-0284 (E.D.N.Y.)), EPA proceeded to develop the
regulations with the existing data, as described below. However, EPA
specifically requested comment on EPA's MACT determinations and on
EPA's conclusions about the performance capabilities of air pollution
control technologies on HMIWI in light of the relatively small database
(60 FR 10686).
a. EPA's Methodology for New HMIWI. In determining the least
stringent regulatory option allowed by the CAA for new HMIWI, EPA first
examined the data available for various air pollution control
technologies applied to HMIWI to determine the performance capabilities
of the technologies (i.e., the achievable emission limitations) (60 FR
10671-73, 61 FR 31741-43). To determine the performance capabilities,
EPA grouped all of the test data by control technology and established
the numerical value for the achievable emission limitations somewhat
higher than the highest test data point for each particular control
technology. (See Legacy Docket ID No. A-91-61, items IV-B-46, 47, 48,
and 49.) Following the determination of performance capability, EPA
identified the best control technology for each air pollutant for each
subcategory of HMIWI, and established the numerical values for the
least stringent regulatory option at the achievable emission limitation
associated with that particular control technology. (See 60 FR 10673;
Legacy Docket ID No. A-91-61, item IV-B-38; 61 FR 31745-46.) Other,
more stringent, regulatory options were developed reflecting the actual
performance of other, more effective, control technologies (61 FR
31766-68).
As stated in the 1996 re-proposal, the least stringent regulatory
option for new large HMIWI units (units with maximum waste burning
capacity of more than 500 lb/hr) was based on good combustion (i.e., 2-
second combustion level) and a combination of two control technologies,
high-efficiency wet scrubbers and dry injection/fabric filter dry
scrubbers with carbon (61 FR 31746). New medium units (units with
maximum waste burning capacity of more than 200 lb/hr but less than or
equal to 500 lb/hr) would need to use good combustion and a combination
of two control technologies, high-efficiency wet scrubbers and dry
injection/fabric filter dry scrubbers without carbon, to meet the least
stringent regulatory option. Id. New small units (units with maximum
waste burning capacity of less than or equal to 200 lb/hr) would need
to use good combustion and a moderate-efficiency wet scrubber to meet
the least stringent regulatory option. Id.
In EPA's final standards promulgated in 1997, EPA selected an
overall more stringent regulatory option for new HMIWI (62 FR 48365).
The final standards were based on emission limits achievable with good
combustion and a
[[Page 5514]]
moderate-efficiency wet scrubber for new small HMIWI, and good
combustion and a combined dry/wet control system with carbon for new
medium and large HMIWI. Id. These standards reflected the MACT floor
emissions levels for new small and large HMIWI, but were more stringent
than the MACT floor for new medium HMIWI. Id. EPA estimated that the
standards would reduce emissions from these units of HCl by up to 98
percent, PM and Pb by up to 92 percent, Cd by up to 91 percent, CDD/CDF
by up to 87 percent, Hg by up to 74 percent, and CO, SO2,
and NOX by up to 52 percent (62 FR 48366).
b. EPA's Methodology for Existing HMIWI. For existing units, EPA
did not have sufficient emissions data to fully characterize the actual
emissions performance of the best performing 12 percent of existing
HMIWI, and, based exclusively on such data, EPA did not have a clear
indication of the technology used by the best 12 percent of units. As a
result, EPA used emission limits included in State regulations and
State-issued permits (hereinafter referred to as regulatory limits) as
surrogate information to determine emissions limitations achieved by
the best performing 12 percent of units in each subcategory (60 FR
10674). EPA believed this information could be expected to reliably
reflect levels of performance achieved on a continuous basis by better-
controlled units that must meet these limits or risk violating
enforceable requirements. EPA assumed that all HMIWI were achieving
their regulatory limits (60 FR 10674). Where there were regulatory
limits for more than 12 percent of units in a subcategory, the
regulatory limits were ranked from the most stringent to least
stringent, and the average of the regulatory limits for the top 12
percent of units in the subcategory was calculated. Id.; 61 FR 31744-
45. Where the number of units subject to specific emissions limitations
did not comprise 12 percent of the population in a subcategory, EPA
assumed those units with regulatory limits were the best performing
units, and the remaining units in the top 12 percent were assigned an
emission value associated with ``combustion control.'' (See 60 FR
10674; 61 FR 31745; Legacy Docket ID No. A-91-61, item IV-B-24 at 2.)
In previous Federal Register notices regarding HMIWI (60 FR 10654, 61
FR 31736, and 62 FR 48348), this level of control was referred to as
``uncontrolled,'' which is misleading because sources with combustion
control emit lesser amounts of CDD/CDF, CO, and PM. In the latter
situation described above, the average of the regulatory limits plus
enough combustion-controlled emission values to account for 12 percent
of units in the subcategory was calculated. (See Legacy Docket ID No.
A-91-61, item IV-B-24 at 2-4.)
After calculating the averages of regulatory limits and combustion-
controlled emission values, EPA examined the resulting calculated
values to determine what level of air pollution control would be needed
to meet the calculated average values. (See 60 FR 10675-78; 61 FR
31755-56.) For many pollutants, the calculated averages presented no
clear indication of the type of air pollution control used by the best
performing units. However, the calculated values for three key
pollutants, PM, CO, and HCl, did provide a good indication of the type
of air pollution control used on the best performing 12 percent of
units. The level of air pollution control associated with the
calculated average values for PM, CO, and HCl formed the technical
basis of the least stringent regulatory option considered by EPA (61 FR
31756, Table 13). The emission limitations assigned to each pollutant
reflected the actual performance of the technology on which they were
based. Finally, EPA developed a series of regulatory options based on
progressively more stringent technologies and assigned emission
limitations to each regulatory option based on the actual performance
capabilities of the technologies (61 FR 31757, Table 14).
As stated in the 1996 re-proposal, large existing units would need
to use good combustion and a high-efficiency wet scrubber to meet the
least stringent regulatory option, while medium existing units would
need to use good combustion and a moderate-efficiency wet scrubber,
although dry scrubbers could also be used with good combustion at large
and medium existing units (61 FR 31745). EPA further stated that its
inclination was to establish emission limitations for large and medium
existing units based on regulatory options representing the MACT floors
(61 FR 31778). Small existing units would need only to use good
combustion practices to meet the regulatory option representing the
MACT floor (61 FR 31745). With respect to small existing units, EPA
stated that it had no inclination with regard to which regulatory
option should be used to establish emission limitations and requested
comment on requiring use of good combustion and a low-efficiency wet
scrubber (61 FR 31778-79).
In EPA's final standards promulgated in 1997, EPA selected an
overall more stringent regulatory option for existing HMIWI (62 FR
48371). The final standards were based on emission limits achievable
with good combustion and a low-efficiency wet scrubber for most
existing small HMIWI, good combustion and a moderate-efficiency wet
scrubber for existing medium HMIWI, and good combustion and a high-
efficiency wet scrubber for existing large HMIWI (62 FR 48371). The
final standards allow small HMIWI that meet certain rural criteria to
meet emissions limits achievable with good combustion alone. Id. These
standards reflected the MACT floor emissions levels for existing small
HMIWI meeting rural criteria, medium HMIWI, and large HMIWI, but were
more stringent than the MACT floor for most existing small HMIWI (i.e.,
non-rural) (62 FR 48371-72). The final standards for existing medium
and large HMIWI were structured so that either a dry scrubber or a wet
scrubber could be used to achieve the emission limits. EPA estimated
that the final emission guidelines would reduce emissions of CDD/CDF by
up to 97 percent, Hg by up to 95 percent, PM by up to 92 percent, Pb by
up to 87 percent, Cd by up to 84 percent, CO by up to 82 percent, HCl
by up to 98 percent, and SO2 and NOX by up to 30
percent (62 FR 48372). Table 1 of this preamble summarizes the emission
limits for the NSPS and emission guidelines promulgated in 1997.
Table 1.--Summary of Promulgated Emission Limits
----------------------------------------------------------------------------------------------------------------
Limit for existing
Pollutant (units) Unit Size \1\ HMIWI \2\ Limit for new HMIWI \2\
----------------------------------------------------------------------------------------------------------------
HCl (parts per million by volume L, M, S............. 100 or 93% 15 or 99% reduction.
(ppmv)). reduction.
SR.................. 3,100............. N/A.\3\
CO (ppmv)....................... L, M, S............. 40................ 40
SR.................. 40................ N/A.
Pb (milligrams per dry standard L, M................ 1.2 or 70% 0.07 or 98% reduction.\3\
cubic meter (mg/dscm)). reduction.
[[Page 5515]]
S................... 1.2 or 70% 1.2 or 70% reduction.
reduction.
SR.................. 10................ N/A.
Cd (mg/dscm).................... L, M................ 0.16 or 65% 0.04 or 90% reduction.
reduction.
S................... 0.16 or 65% 0.16 or 65% reduction.
reduction.
SR.................. 4................. N/A.
Hg (mg/dscm).................... L, M, S............. 0.55 or 85% 0.55 or 85% reduction.
reduction.
SR.................. 7.5............... N/A.
PM (grains per dry standard L................... 0.015............. 0.015
cubic foot (gr/dscf)).
M................... 0.03.............. 0.015
S................... 0.05.............. 0.03.
SR.................. 0.086............. N/A.
CDD/CDF, total (nanograms per L, M................ 125............... 25
dry standard cubic meter (ng/
dscm)).
S................... 125............... 125
SR.................. 800............... N/A.
CDD/CDF, TEQ (ng/dscm).......... L, M................ 2.3............... 0.6
S................... 2.3............... 2.3
SR.................. 15................ N/A.
NOX (ppmv)...................... L, M, S............. 250............... 250
SR.................. 250............... N/A.
SO2 (ppmv)...................... L, M, S............. 55................ 55
SR.................. 55................ N/A.
----------------------------------------------------------------------------------------------------------------
\1\ L = Large; M = Medium; S = Small; SR = Small Rural
\2\ All emission limits are measured at 7 percent oxygen.
\3\ Not applicable.
c. Compliance by HMIWI. At the time of promulgation (September
1997), EPA estimated that there were approximately 2,400 HMIWI
operating in the United States. Those units combusted approximately 830
thousand tons of hospital/medical/infectious waste annually. Of those
existing HMIWI, about 48 percent were small units, 29 percent were
medium units, and 20 percent were large units. About 3 percent of the
HMIWI were commercial units. EPA projected that no new small or medium
HMIWI would be constructed, and that up to 60 new large units and 10
new commercial units would be constructed.
After shutdown of approximately 97 percent of the 2,400 HMIWI that
were operating in 1997, there are currently 72 existing HMIWI at 67
facilities. Additionally, only 4 new HMIWI at 3 facilities began
operation following the 1997 rulemaking. These 76 existing and new
units are estimated to combust approximately 165 thousand tons of waste
annually. Of the 72 existing HMIWI subject to the emission guidelines,
44 are large units, 20 are medium units, and 8 are small units (6 of
which meet the rural criteria). Twenty-one percent of the existing
HMIWI are commercially owned. Of the four new HMIWI, three are large
units, and one is a medium unit. Two of the new units are county-owned
but accept waste from other sources, similar to commercial units. The
actual emissions reductions achieved as a result of implementation of
the standards exceeded the 1997 projections for all nine of the
regulated pollutants. A comparison of the estimated pollutant
reductions versus the actual reductions is presented in Table 2 of this
preamble.
Table 2.--Comparison of Estimated Pollutant Reductions Versus Actual
Pollutant Reductions
------------------------------------------------------------------------
Estimated
emissions Actual emissions
Pollutant reduction, reduction, percent
percent \1\
------------------------------------------------------------------------
HCl............................. 98................ 99.2
CO.............................. 75 to 82.......... 98.1
Pb.............................. 80 to 87.......... 98.7
Cd.............................. 75 to 84.......... 99.0
Hg.............................. 93 to 95.......... 99.0
PM.............................. 88 to 92.......... 98.1
CDD/CDF, total.................. 96 to 97.......... 99.5
CDD/CDF, TEQ.................... 95 to 97.......... 99.6
NOX............................. 0 to 30........... 70.6
SO2............................. 0 to 30........... 92.6
------------------------------------------------------------------------
\1\ Reflects the effect of unit shutdowns as well as the effect of
compliance with the promulgated standards.
3. What was the Sierra Club's challenge?
On November 14, 1997, the Sierra Club and the Natural Resources
Defense Council (Sierra Club) filed suit in the U.S. Court of Appeals
for the District of Columbia Circuit (the Court). The Sierra Club
claimed that EPA had violated CAA section 129 by setting emission
standards for HMIWI under CAA sections 129 and 111 that are less
stringent than the statutory minimum stringency required by section
129(a)(2); that EPA had violated section 129 by not including mandatory
pollution prevention or waste minimization requirements in the HMIWI
standards; and that EPA had not adequately considered the non-air
quality health and environmental impacts of the standards. For new
units, the Sierra
[[Page 5516]]
Club argued that to satisfy the statutory phrase ``best controlled
similar unit'' in CAA section 129(a)(2), EPA should have identified the
single best performing unit in each subcategory and based the MACT
floor for that subcategory on that particular unit's performance,
rather than consider the performance of other units using the same
technology. The Sierra Club also argued that EPA erroneously based the
new unit floors on the emissions of the worst performing unit using a
particular technology. Regarding existing units, the Sierra Club
claimed that the plain meaning of CAA section 129(a)(2)'s words,
``average emissions limitation achieved by the best performing 12
percent of units,'' precludes the use of regulatory data, and claimed
that the legislative history of section 129(a)(2) reflects
congressional intent to prohibit EPA from relying on regulatory data.
Moreover, the Sierra Club claimed that, for HMIWI, using regulatory
data was impossible because such data existed for fewer than 12 percent
of units, and because doing so would impermissibly import an
achievability requirement into the unit floor determination. Finally,
the Sierra Club argued that EPA failed to require HMIWI units to
undertake programs to reduce the Hg and chlorinated plastic in their
waste streams, in violation of CAA section 129(a)(3), and that EPA
failed to consider the fact that CDD/CDF and Hg from HMIWI can
contaminate water, sediment, and soil, and can bioaccumulate in food,
in violation of the CAA's requirement that EPA consider non-air quality
impacts of setting HMIWI emissions standards.
4. What was the Court's ruling?
On March 2, 1999, the Court issued its opinion in Sierra Club v.
EPA, 167 F.3d 658 (D.C. Cir. 1999). While the Court rejected the Sierra
Club's claims regarding pollution prevention and non-air quality
impacts, and rejected the Sierra Club's statutory arguments under CAA
section 129, the Court remanded the rule to EPA for further explanation
regarding how EPA derived the MACT floors for new and existing HMIWI
units. Furthermore, the Court did not vacate the regulations, stating
that ``[i]t is possible that EPA may be able to explain [EPA's basis
for the standards]'' in response to the concerns raised by the Court.
Id., at 664. The regulations remain in effect during the remand.
a. The Court's Ruling on New Units. In response to the Sierra
Club's claims regarding EPA's treatment of new units, the Court opined
that ``EPA would be justified in setting the floors at a level that is
a reasonable estimate of the performance of the `best controlled
similar unit' under the worst reasonably foreseeable circumstances [* *
*]. It is reasonable to suppose that if an emissions standard is as
stringent as `the emissions control that is achieved in practice' by a
particular unit, then that particular unit will not violate the
standard. This only results if `achieved in practice' is interpreted to
mean `achieved under the worst foreseeable circumstances.' In National
Lime Ass'n v. EPA, 627 F.2d 416, 431 n. 46 (D.C. Cir. 1980), we said
that where a statute requires that a standard be `achievable,' it must
be achievable `under most adverse circumstances which can reasonably be
expected to recur.' The same principle should apply when a standard is
to be derived from the operating characteristics of a particular
unit.'' Sierra Club v. EPA, 167 F.3d at 665. Thus, the Court refused to
embrace the Sierra Club's interpretation of CAA section 129(a)(2) as
requiring EPA to base the MACT floor on only the lowest emissions data
points observed (i.e., the level achieved by the best performing unit
for each pollutant).
Relating to the Sierra Club's claim that EPA erred in considering
the emissions of units other than the best controlled unit, the Court
refused to rule that EPA's approach was unlawful, and posited that
``[p]erhaps considering all units with the same technology is
justifiable because the best way to predict the worst reasonably
foreseeable performance of the best unit with the available data is to
look at other units' performance. Or perhaps EPA reasonably considered
all units with the same technology equally `well-controlled,' so that
each unit with the best technology is a `best-controlled unit' even if
such units vary widely in performance.'' Sierra Club v. EPA, 167 F.3d
at 665.
However, the Court concluded that the possible rationale for this
treatment of new units was not presented in the rulemaking record with
enough clarity for the Court to determine that EPA's ``path may
reasonably be discerned.'' Id. Moreover, the Court ruled that EPA had
``not explained why the phrase best controlled similar unit encompasses
all units using the same technology as the unit with the best observed
performance, rather than just that unit itself[. * * * W]e do not know
what interpretation the agency chose, and thus cannot evaluate its
choice.'' Sierra Club v. EPA, 167 F.3d at 665. The Court further
directed EPA to provide additional explanation regarding how the Agency
had calculated the upper bound of the best-controlled unit's
performance through rounding. Id.
b. The Court's Ruling on Existing Units. With respect to existing
units, the Court first rejected the Sierra Club's ``claim that EPA's
decision to base the floors on regulatory data fails the first step of
the Chevron test. None of the Sierra Club's arguments establish that
Congress has `directly addressed' and rejected the use of regulatory
data.'' Id., at 661. After noting that the Sierra Club's statutory
objections to EPA's methodology appeared to be premised on ``the
counterintuitive proposition that an `achieved' level may not be
`achievable,' or, as Sierra Club puts it, may be better than `EPA's
notions about what is achievable,' '' id. at 662, the Court rejected
the Sierra Club's statutory objections to using regulatory data and
uncontrolled (i.e., combustion-controlled) emissions values. In other
words, the Court implicitly embraced EPA's view, under the principle of
National Lime, that the MACT floor is premised on the fundamental
concept that it be ``achievable,'' and should not be set at a level
that happens to be reflected by the lowest observed data point without
consideration of variability in operating conditions. Then, after
analyzing and rejecting the Sierra Club's arguments that the plain
language of the CAA and its legislative history forbid EPA's
methodology, the Court further ruled that it found ``nothing inherently
impermissible about construing the statute to permit the use of
regulatory data--if they allow EPA to make a reasonable estimate of the
performance of the top 12 percent of units. Indeed, the Sierra Club
conceded at oral argument that `a reasonable sample' may be used `to
find out what the best 12 percent are doing.' Oral Arg. Tr. at 11. To
be sure, the Sierra Club did not concede that permit data may be used.
But neither has it provided any basis for believing that state and
local limitations are such weak indicators of performance that using
them is necessarily an impossible stretch of the statutory terms. [* *
*] We therefore reject the Sierra Club's argument that the CAA forbids
the use of permit and regulatory data, and hold that the use of such
information is permissible as long as it allows a reasonable inference
as to the performance of the top 12 percent of units. Similarly, as
long as there is a reasonable basis for believing that some of the best
performing 12 percent of units are uncontrolled [i.e., combustion
controlled], EPA may include data points giving a reasonable
representation of the performance of those units in its averaging.''
Sierra Club v. EPA, 167 F.3d at 662, 663. Thus, the Court rejected all
of the Sierra Club's
[[Page 5517]]
arguments that the CAA prohibits EPA from basing MACT floor
determinations on permit or regulatory data, or on uncontrolled (i.e.,
combustion-controlled) emissions values.
However, in addressing the manner in which EPA had specifically
relied upon such data in the HMIWI rulemaking, the Court concluded that
``[a]lthough EPA said that it believed the combination of regulatory
and uncontrolled [i.e., combustion-controlled] data gave an accurate
picture of the relevant [HMIWI]s` performance, it never adequately said
why it believes this. [* * *] First, EPA has said nothing about the
possibility that [HMIWI]s might be substantially overachieving the
permit limits. If this were the case, the permit limits would be of
little value in estimating the top 12 percent of [HMIWI]s' performance.
[* * *] Second, EPA never gave any reason for its apparent belief that
[HMIWI]s that were not subject to permit requirements did not deploy
emission controls of any sort. Unless there is some finding to this
effect, it is difficult to see the rationality in using `uncontrolled'
[i.e., combustion-controlled] data for the units that were not subject
to regulatory requirements.'' Id., at 663-664. The Court further
questioned the rationality of EPA using the highest of its test run
data in cases where the regulatory data did not alone comprise the
necessary 12 percent. Id., at 664.
c. Subsequent Court Rulings Relevant to the Remand. Following the
Court's remand of the HMIWI MACT floors in Sierra Club v. EPA, the
Court issued a series of rulings in other cases addressing MACT rules
that bear on EPA's proposed response regarding HMIWI. The first of
these was Nat'l Lime Ass'n v. EPA, 233 F.3d 625 (D.C. Cir. 2000) (``NLA
II''), which involved challenges to EPA's MACT standards under CAA
section 112(d) for portland cement manufacturing facilities. In that
case, the Sierra Club argued that EPA should have based its estimate of
the top performing 12 percent of sources on actual emissions data, in
order to ``reasonably estimate'' such performance. But the Court
determined that EPA's approach of selecting ``the median [performing]
plant out of the best twelve percent of the plants for which it had
information and set[ting] the * * * floor at the level of the worst
performing plant in its databases using th[e same] technology [as the
median plant]'' had not been shown by the Sierra Club to reflect a not
reasonable estimate. NLA II, 233 F.3d at 633.
In addition, the Court partially clarified its position regarding
EPA's approach of accounting for emissions performance variability by
setting floors at a level that reasonably estimates ``the performance
of the `best controlled similar unit' under the worst reasonably
foreseeable circumstances.'' Sierra Club, 167 F.3d at 665. In NLA II,
the Court stressed that EPA should not simply set floors at levels
reflecting the worst foreseeable circumstances faced by any worst
performing unit in a given source category, and that while considering
all units with the same technology may be justifiable because the best
way to predict the worst reasonably foreseeable performance of the best
unit with available data is to look at other units' performance, such
an approach would satisfy the CAA ``if pollution control technology
were the only factor determining emission levels of that HAP.'' NLA II,
233 F.3d at 633.
In Cement Kiln Recycling Coalition v. EPA, 255 F.3d 855 (D.C. Cir.
2001) (``CKRC''), the Court again refined its view on when it is
appropriate for EPA to base MACT floors on the performance of air
pollution control technology. In that case, the Sierra Club challenged
EPA's MACT standards for hazardous waste combustors (HWC), and argued
that factors other than MACT technology influenced the emissions
performance of the best performing sources.
The Court agreed that since EPA's record evidence in the HWC
rulemaking showed that factors besides MACT controls significantly
influenced HWC emission rates, ''emissions of the worst-performing MACT
source may not reflect what the best-performers actually achieve.''
CKRC, 255 F.3d at 864. EPA had claimed that MACT floors must be
achievable by all sources using MACT technology, and that to account
for the best-performing sources'' operational variability we had to
base floors on the worst performers'' emissions. But the Court stressed
that ``whether variability in the MACT control accurately estimates
variability associated with the best performing sources depends on
whether factors other than MACT control contribute to emissions[,]''
id., and that ``the relevant question here is not whether control
technologies experience variability at all, but whether the variability
experienced by the best-performing sources can be estimated by relying
on emissions data from the worst-performing sources using the MACT
control.'' Id., at 865.
In the specific case of the HWC rule, the Court concluded that,
since record evidence showed that non-MACT factors influenced emissions
performance, EPA could not base floors simply on the worst-performing
MACT sources' emissions. Id., at 866. However, the Court also
reiterated that ``[i]f in the case of a particular source category or
HAP, the Agency can demonstrate with substantial evidence--not mere
assertions--that MACT technology significantly controls emissions, or
that factors other than the control have a negligible effect, the MACT
approach could be a reasonable means of satisfying the statute's
requirements.'' Id.
5. Are revisions to the emission limits being proposed in response to
the remand?
Yes, the proposed response to the remand would revise some of the
emission limits in both the NSPS and emission guidelines. Relative to
the NSPS, the emission limits for CO, Pb, Cd, Hg, PM, and CDD/CDF would
be revised. Relative to the emission guidelines, the emission limits
for HCl, Pb, Cd, and CDD/CDF would be revised. EPA believes that the
revised emission limits being proposed as a result of its response to
the remand can be achieved with the same emission control technology
currently used by HMIWI. The proposed emission limits for the NSPS and
emission guidelines necessary to respond to the Court's remand are
summarized in Table 3 of this preamble. Note that in several cases,
further amendments to the emission limits are being proposed as a
result of our 5-year review under CAA section 129(a)(5). Those proposed
amendments are discussed in the following section of this preamble.
Table 3.--Summary of Proposed Emission Limits in Response to the Remand
----------------------------------------------------------------------------------------------------------------
Proposed remand
Pollutant (units) Unit size \1\ limit for Proposed remand limit for new HMIWI
existing HMIWI \2\ \2\
----------------------------------------------------------------------------------------------------------------
HCl (ppmv)...................... L, M, S............. 78 or 93% 15\3\ or 99% reduction \3\.
reduction \3\.
SR.................. 3,100 \3\......... N/A \4\.
CO (ppmv)....................... L, M, S............. 40 \3\............ 32
SR.................. 40 \3\............ N/A \4\.
[[Page 5518]]
Pb (mg/dscm).................... L, M................ 0.78 or 71% 0.060 or 98% reduction \3\.
reduction.
S................... 0.78 or 71% 0.78 or 71% reduction.
reduction.
SR.................. 8.9............... N/A \4\.
Cd (mg/dscm).................... L, M................ 0.11 or 66% 0.030 or 93% reduction.
reduction \3\.
S................... 0.11 or 66% 0.11 or 66% reduction \3\.
reduction \3\.
SR.................. 4 \3\............. N/A \4\.
Hg (mg/dscm).................... L, M................ 0.55 \3\ or 87% 0.45 or 87% reduction.
reduction.
S................... 0.55 \3\ or 87% 0.47 or 87% reduction.
reduction.
SR.................. 6.6............... N/A \4\.
PM (gr/dscf).................... L................... 0.015 \3\......... 0.009
M................... 0.030 \3\......... 0.009
S................... 0.050 \3\......... 0.018
SR.................. 0.086 \3\......... N/A \4\.
CDD/CDF, total (ng/dscm)........ L, M................ 115............... 20
S................... 115............... 111
SR.................. 800 \3\........... N/A \4\.
CDD/CDF, TEQ (ng/dscm).......... L, M................ 2.2............... 0.53
S................... 2.2............... 2.1
SR.................. 15 \3\............ N/A \4\.
NOX (ppmv)...................... L, M, S............. 250 \3\........... 225
SR.................. 250 \3\........... N/A \4\
SO2 (ppmv)...................... L, M, S............. 55 \3\............ 46
SR.................. 55 \3\............ N/A \4\.
----------------------------------------------------------------------------------------------------------------
\1\ L = Large; M = Medium; S = Small; SR = Small Rural
\2\ All emission limits are measured at 7 percent oxygen.
\3\ No change proposed.
\4\ Not applicable.
B. Proposed Amendments (CAA Section 129(a)(5) 5-Year Review)
Section 129(a)(5) of the CAA requires EPA to conduct a review of
the NSPS and emissions guidelines at 5 year intervals and, if
appropriate, revise the NSPS and emission guidelines pursuant to the
requirements under sections 111 and 129 of the CAA. In conducting such
reviews, EPA attempts to assess the performance of and variability
associated with the installed emissions control equipment (and
developments in practices, processes and control technologies) and to
revise as necessary and appropriate the NSPS and emission guidelines.
In these reviews, EPA takes into account the currently installed
equipment and its performance and operational variability. As
appropriate, we also consider new technologies that have been
demonstrated to reliably control emissions from the source category. In
setting numerical emission limits from single, ``snap shot'' stack test
data, EPA must exercise technical judgment to ensure the achievability
of such limits over the course of anticipated operating conditions. EPA
has completed the 5-year review, and the proposed amendments discussed
below reflect the changes that EPA has determined are appropriate in
addition to the amendments that are necessary to respond to the Court's
remand. These proposed amendments do not reflect adoption of new
control technologies or processes, but do reflect more efficient
practices in operation of the control technologies that sources used in
order to meet the 1997 MACT standards.
Following year 2002 compliance with the emission guidelines, EPA
gathered information on the performance levels actually being achieved
by HMIWI that were operating under the guidelines. After implementation
of the guidelines in 1997, approximately 94 percent of HMIWI shut down,
and 3 percent demonstrated eligibility for exemptions from the HMIWI
regulation. Those HMIWI that remained in operation either continued
operation with their existing configuration or were retrofitted with
add-on air pollution control devices in order to meet the standards.
The retrofits were completed on time, and the controls installed to
meet the required emission limitations were highly effective in
reducing emissions of all of the CAA section 129 pollutants emitted by
HMIWI. For those HMIWI, relative to a 1995 baseline, the emission
guidelines reduced organic emissions (CDD/CDF) by about 90 percent,
metals emissions (Pb, Cd, and Hg) by more than 80 percent, and acid gas
emissions (HCl and SO2) by more than 70 percent. Including
shutdowns and exemptions, nationwide HMIWI emissions of organics,
metals, and acid gases each decreased by about 99 percent or more
relative to a 1995 baseline. It should be noted that the original HMIWI
emission limits were based primarily on permit information and other
regulatory requirements, and not on actual performance or stack test
data. To this end, it was highly uncertain at promulgation what the
precise performance efficiency and day-to-day operational variability
associated with the promulgated regulatory requirements would yield.
Thus, the 2002 compliance test information provided the first
quantitative assessment of the performance of the installed control
equipment's ability to attain the NSPS and emissions guideline limits.
The goal of the current technology review is to assess the
performance efficiency of the installed equipment and to ensure that
the emission limits reflect the performance of the technologies
required by the MACT standards. In addition, the review addresses
whether new technologies and processes and improvements in practices
have been demonstrated at sources subject to the emissions limitations.
EPA's intent for future technology reviews is to include similar
analyses that also assess risk along with new technologies. For the
current review, while new technologies have not yet been demonstrated
to reliably control emissions more efficiently at reasonable cost at
HMIWI units than those used to meet MACT, improvements in operational
practices
[[Page 5519]]
do support some additional revision of the standards, in order to
better reflect the best operation of the MACT controls.
These proposed amendments would revise the NSPS and emission
guidelines, in some cases beyond the point needed to respond to the
Court's remand, based on the performance levels currently being
achieved by HMIWI. The revisions discussed in the following text apply
to both the NSPS and the emission guidelines, unless otherwise
specified.
1. Are revisions to the emission limits being proposed?
Yes, the proposed amendments would revise the emission limits in
both the NSPS and emission guidelines. EPA's technology review
demonstrates that the proposed emission limits can be achieved with the
same emission control technology currently used by HMIWI. The proposed
emission limits for the NSPS and emission guidelines are summarized in
Tables 4 and 5 of this preamble.
Table 4.--Summary of Proposed 5-Year Review Emission Limits for New HMIWI
----------------------------------------------------------------------------------------------------------------
Pollutant (units) Unit Size \1\ Proposed Limit \2\
----------------------------------------------------------------------------------------------------------------
HCl (ppmv)........................... L, M, S...................... 15 \3\ or 99% reduction \3\.
CO (ppmv)............................ L, M, S...................... 25
Pb (mg/dscm)......................... L, M......................... 0.060 or 99% reduction.
S............................ 0.64 or 71% reduction.
Cd (mg/dscm)......................... L, M......................... 0.0050 or 99% reduction.
S............................ 0.060 or 74% reduction.
Hg (mg/dscm)......................... L, M......................... 0.19 or 96% reduction.
S............................ 0.33 or 96% reduction.
PM (gr/dscf)......................... L, M......................... 0.0090.
S............................ 0.018.
CDD/CDF, total (ng/dscm)............. L, M......................... 16
S............................ 111
CDD/CDF, TEQ (ng/dscm)............... L, M......................... 0.21
S............................ 2.0
NOX (ppmv)........................... L, M, S...................... 212
SO2 (ppmv)........................... L, M......................... 21
S............................ 28
----------------------------------------------------------------------------------------------------------------
\1\ L = Large; M = Medium; S = Small
\2\ All emission limits are measured at 7 percent oxygen.
\3\ No change proposed.
Table 5.--Summary of Proposed 5-Year Review Emission Limits for Existing HMIWI
----------------------------------------------------------------------------------------------------------------
Pollutant (units) Unit Size \1\ Proposed Limit \2\
----------------------------------------------------------------------------------------------------------------
HCl (ppm)............................ L, M, S...................... 51 or 94% reduction.
SR........................... 398
CO (ppm)............................. All.......................... 25
Pb (mg/dscm)......................... L, M, S...................... 0.64 or 71% reduction.
SR........................... 0.60
Cd (mg/dscm)......................... L, M, S...................... 0.060 or 74% reduction.
SR........................... 0.050
Hg (mg/dscm)......................... L, M, S...................... 0.33 or 96% reduction.
SR........................... 0.25\3\
PM (gr/dscf)......................... L............................ 0.015
M............................ 0.030 \3\
S............................ 0.030
SR........................... 0.030
CDD/CDF, total (ng/dscm)............. L, M, S...................... 115
SR........................... 800 \3\
CDD/CDF, TEQ (ng/dscm)............... L, M, S...................... 2.0
SR........................... 15 \3\
NOX (ppmv)........................... All.......................... 212
SO2 (ppmv)........................... All.......................... 28
----------------------------------------------------------------------------------------------------------------
\1\ L = Large; M = Medium; S = Small; SR = Small Rural
\2\ All emission limits are measured at 7 percent oxygen.
\3\ No change proposed.
As indicated by Table 5 of this preamble, the proposed emission
limits for Pb, Cd, and Hg for existing small rural HMIWI are more
stringent than those being proposed for existing large, medium, and
small HMIWI. We believe that this better emissions performance by
existing small rural HMIWI is a result of the waste stream of a small
rural hospital not including certain materials that are in the waste
stream of a non-rural hospital and that cause relatively higher Pb, Cd
and Hg emissions.
2. Are other amendments being proposed?
The proposed amendments would also make the following changes based
on information received during implementation of the HMIWI NSPS and
emission guidelines and would
[[Page 5520]]
apply equally to the NSPS and emission guidelines, unless otherwise
specified.
a. Performance Testing and Monitoring Amendments. The proposed
amendments would allow sources to use the results of previous emissions
tests to demonstrate compliance with the revised emission limits as
long as the sources certify that the previous test results are
representative of current operations. Only those sources whose previous
emissions tests do not demonstrate compliance with one or more revised
emission limits would be required to conduct another emissions test for
those pollutants (note that sources are already required to test for
HCl, CO, and PM on an annual basis). The proposed amendments would
require, for existing HMIWI, annual inspections of scrubbers and fabric
filters, and a one-time Method 22 visible emissions test of the ash
handling operations to be conducted during the next compliance test.
For new HMIWI, the proposed amendments would require CO continuous
emissions monitoring systems (CEMS), bag leak detection systems for
fabric-filter controlled units, annual inspections of scrubbers and
fabric filters, and Method 22 visible emissions testing of the ash
handling operations to be conducted during each compliance test. For
existing HMIWI, use of CO CEMS would be an approved alternative, and
specific language with requirements for CO CEMS is included in the
proposed amendments. For new and existing HMIWI, use of PM, HCl, multi-
metals, and Hg CEMS, and semi-continuous dioxin monitoring (continuous
sampling with periodic sample analysis) also are approved alternatives,
and specific language for these alternatives is included in the
proposed amendments.
b. Other Amendments. The proposed amendments would revise the
definition of ``Minimum secondary chamber temperature'' to read
``Minimum secondary chamber temperature means 90 percent of the highest
3-hour average secondary chamber temperature (taken, at a minimum, once
every minute) measured during the most recent performance test
demonstrating compliance with the PM, CO, and dioxin/furan emission
limits.''
The proposed amendments would require sources to submit, along with
each test report, a description of how operating parameters are
established during the initial performance test and subsequent
performance tests.
3. Is an implementation schedule being proposed?
Yes; under the proposed amendments to the emission guidelines, and
consistent with CAA section 129, revised State plans containing the
revised emission limits and other requirements in the proposed
amendments would be due within 1 year after promulgation of the
amendments. That is, revised State plans would have to be submitted to
EPA 1 year after the date on which EPA promulgates revised standards.
The proposed amendments to the emission guidelines then would allow
HMIWI units up to 3 years from the date of approval of a State plan,
but not later than 5 years after promulgation of the revised standards,
to demonstrate compliance with the amended standards. Consistent with
CAA section 129, EPA expects States to require compliance as
expeditiously as practicable. HMIWI units have already installed the
emission control equipment necessary to meet the proposed revised
limits, and EPA, therefore, anticipates that most State plans will
include compliance dates sooner than 5 years following promulgation of
the amendments. In most cases, the only changes necessary are to review
the revisions and adjust the emission monitoring and reporting
accordingly.
In revising the emission limits in a State plan, a State has two
options. First, it could include both the current and the new emission
limits in its revised State plan, which allows a phased approach in
applying the new limits. That is, the State plan would make it clear
that the current emission limits remain in force and apply until the
date the new emission limits are effective (as defined in the State
plan). States whose HMIWI units do not find it necessary to improve
their performance in order to meet the new emission limits may want to
consider a second approach where the State would insert the new
emission limits in place of the current emission limits, follow
procedures in 40 CFR part 60, subpart B, and submit a revised State
plan to EPA for approval. If the revised State plan contains only the
new emission limits (i.e., the current emission limits are not
retained), then the new emission limits must become effective
immediately since the current limits would be removed from the State
plan.
4. Has EPA changed the applicability date of the 1997 NSPS?
No; however, HMIWI may be treated differently under the amended
standards than they were under the 1997 standards in terms of whether
they are ``existing'' or ``new'' sources, and there will be new dates
defining what are ``new'' sources and imposing compliance deadlines
regarding any amended standards. The applicability date for the NSPS
units, with respect to the standards as promulgated in 1997, remains
June 20, 1996; however, units for which construction is commenced after
the date of this proposal, or modification is commenced on or after the
date 6 months after promulgation of the amended standards, would be
subject to more stringent NSPS emission limits than units for which
construction or modification was completed prior to those dates. Under
the proposed amendments, units that commenced construction after June
20, 1996, and on or before February 6, 2007, or that are modified
before the date 6 months after the date of promulgation of any revised
final standards, would continue to be or would become subject to the
NSPS emission limits that were promulgated in 1997 and that remain in
the 40 CFR part 60, subpart Ec NSPS, except where the revised emission
guidelines would be more stringent. In that case, HMIWI that are NSPS
units under the 1997 rule would also need to comply with the revised
emission guidelines for existing sources, by the applicable compliance
date for such existing sources. Similarly, emission guidelines units
under the 1997 rule would need to meet the revised emission guidelines
by the applicable compliance date for the revised guidelines. HMIWI
that commence construction after February 6, 2007 or that are modified
6 months or more after the date of promulgation of any revised
standards would have to meet the revised NSPS emission limits being
added to the subpart Ec NSPS and any remaining NSPS limits from the
1997 rule, as applicable, within 6 months after the promulgation date
of the amendments or upon startup, whichever is later.
IV. Rationale
A. Rationale for the Proposed Response to the Remand
This action responds to the Court's remand by (1) further
explaining the reasoning processes by which EPA determined the MACT
floors and the MACT standards for new and existing HMIWI for the
portions of those processes that are being retained under our remand
response, and (2) explaining revisions to the processes, the MACT
floors, and the MACT standards for new and existing HMIWI that result
from our response to the remand.
1. New HMIWI
The Court raised three issues with regard to EPA's treatment of the
MACT floor for new units and the achievable
[[Page 5521]]
emission limitations. First, the Court asked EPA to explain why the
floor was based on the highest emissions levels of the ``worst-
performing'' unit employing the MACT technology rather than on the
lowest observed emissions levels of the best performing unit using the
MACT technology. (See Sierra Club v. EPA, 167 F.3d at 665.) Second, the
Court requested further explanation of why EPA considered multiple
units employing the MACT technology, rather than identify the single
best-performing unit and basing the floor on that particular unit's
performance with that technology. Id. Third, the Court requested
further explanation of EPA's procedure for determining the achievable
emission limitation from the available data, where EPA selected a
numerical value somewhat higher than the highest observed data point.
The Court stated that EPA's procedure ``[m]ay be justifiable as a means
of reasonably estimating the upper bound of the best-controlled unit's
performance, but in the absence of agency explanation of both the
decision to increase the levels and the choice of method for
determining the increases, we are in no position to decide.'' Id.
As discussed in detail below, for the first two issues, the Court
described potential rationale for EPA's method. However, because the
Court concluded that this rationale was not adequately presented in the
rulemaking record, the Court asked for further clarification by EPA. In
subsequent cases the Court further addressed these potential
rationales, and discussed under what circumstances they would and would
not be persuasive. In fact, the Court's potential rationale for EPA's
method reflects the principles used by EPA in determining the MACT
floor for new units and the achievable emission limitations for this
source category, and is the method that has been used by EPA throughout
most of the Agency's 30-year history in developing achievable
technology-based emission limitations for source categories in cases
where the application of control technology has been the only means by
which sources have limited emissions, and the variability of technology
performance is a critical factor in determining an emission
limitation's achievability. (See, e.g., American Iron and Steel Inst.
v. EPA, 115 F.3d 979, 1000 (D.C. Cir. 1997); BP Exploration & Oil,
Inc., v. EPA, 66 F.3d. 784, 794 (6th Cir. 1995); NRDC v. EPA, 790 F.2d
289, 299 (3d Cir. 1986); National Ass'n of Metal Finishers v. EPA, 719
F.2d 624, 659 (3d Cir. 1983); rev'd on other grounds sub nom, Chemical
Mfrs. Ass'n v. NRDC, 470 U.S. 116 (1985); American Petroleum Inst. v.
EPA, 661 F.2d 340, 347 n. 23 (5th Cir. 1981); Bunker Hill Co. v. EPA,
572 F.2d 1286, 1302 (9th Cir. 1977); Marathon Oil Co. v. EPA, 564 F.2d
1253, 1266-67 (9th Cir. 1977); FMC v. Train, 639 F.2d 973, 985-86 (4th
Cir. 1976).) As discussed elsewhere in this preamble, in CKRC the Court
stressed that where record evidence suggests that factors other than
application of control technology influence emissions, EPA will not be
able to demonstrate ``that floors based on the worst-performing MACT
sources' emissions represent `a reasonable estimate of the performance
of the [best-performing] units.' '' CKRC, 255 F.3d at 866, quoting
Sierra Club, 167 F.3d at 662. However, the Court reiterated that where
EPA's record demonstrates that MACT technology significantly controls
emissions, or that factors other than the control have a negligible
effect, the approach of accounting for variability by basing the floor
on the highest emissions resulting from a source using MACT technology
``could be a reasonable means of satisfying the statute's
requirements.'' CKRC, at 866.
a. Applicability of National Lime to CAA Section 129. CAA section
129(a)(3) states that ``[s]tandards under section 111 and this section
applicable to solid waste incineration units shall be based on methods
and technologies for removal or destruction of pollutants before,
during, or after combustion [* * *].'' This language requires that such
a standard be based on the degree of reduction in air pollutant
emissions that can be achieved through application of a particular
method of pollution control, and any other factors that record evidence
shows significantly affect emissions performance. Much like the
language in CAA sections 111 and 129 governing the HMIWI standards,
Congress has used similar language in other statutes to direct adoption
of technology-based standards. (See, e.g., CAA section 169(3) defining
``best available control technology''; Clean Water Act section
301(b)(2)(A), for ``best available technology economically achievable''
or ``BAT'' standards; Clean Water Act section 304(b)(1) for ``best
practicable technology'' or ``BPT'' standards.)
As the Court has stated, ``[t]echnology-based provisions [in the
CAA] require EPA to promulgate standards only after finding that the
requisite technology exists or may be feasibly developed. Absolute
standards, on the other hand, require compliance with statutorily
prescribed standards and time tables, irrespective of present
technologies.'' (See NRDC v. Reilly, 983 F.2d 259, 268 (D.C. Cir. 1993)
(holding that elimination of feasibility requirements and specification
of particular control systems indicated that congressional amendment of
CAA section 202(a)(6) resulted in an ``absolute'' standard).) MACT
standards under CAA sections 111 and 129 are ``technology-based,''
rather than ``absolute'' standards. The legislative history to the 1990
CAA Amendments clearly shows that Congress intended the MACT standards
to be technology-based. (See I A Legislative History, at 863 (Senator
Durenberger referring to ``the MACT technology-based standards'' in
debates on the bill reported by the Conference Committee); id., at 1128
(Senator Dole explaining that changes made to CAA section 129 in the
Conference Committee ``make the technology test more closely
approximate the role of the NSPS''); S. Rep. No. 101-228, at 133-134
(1989) (referring to CAA section 112 MACT standards as ``technology-
based standards'' and noting that technology-based effluent standards
under the Clean Water Act served as a model for the new MACT
standards).)
CAA section 129 does not specify a type of control technology for
HMIWI, but instead requires EPA to develop floor levels already
achieved in practice by one or more units, and then issue standards
that EPA determines are ``achievable'' for units in that source
category. As the Court stated in National Lime Ass'n v. EPA (627 F.2d
416, 431 n. 46 (D.C. Cir. 1980)) (``NLA I''), and restated in Sierra
Club, ``where a statute requires a standard to be achievable, it must
be achievable `under most adverse circumstances which can reasonably be
expected to recur.' '' (See Sierra Club, 167 F.3d at 665.) In other
words, ``EPA would be justified in setting floors at a level that is a
reasonable estimate of the performance of the `best controlled similar
unit'' under the worst reasonably foreseeable circumstances[.]'' Id.
This concept of ``worst reasonably foreseeable circumstances'' is
fundamental in developing achievable technology-based emission
limitations, since, once the standard is in force, sources will be
expected to comply with it at all times by relying on the technology
that formed the basis for EPA's determination that the promulgated
emissions limitation is achievable. As the Court stated in Sierra Club,
`[i]t is reasonable to suppose that if an emissions standard is as
stringent as `the emissions control that is achieved in practice' by a
particular unit, then that particular unit will not violate the
standard. This only results if `achieved in practice' is interpreted to
[[Page 5522]]
mean `achieved under the worst foreseeable circumstances.' '' Id.
EPA agrees with the Court that, in order to satisfy the
requirements of NLA I, ``[t]he same principle should apply when a
standard is to be derived from the operating characteristics of a
particular unit[,]'' as is the case under CAA section 129(a)(2). Id.
CAA section 129(a)(2) requires that the new unit MACT floor be ``not
less stringent than the emissions control that is achieved in practice
by the best controlled similar unit, as determined by the
Administrator.'' It would have been unreasonable for EPA to base the
MACT floors solely on the lowest levels of emissions observed without
an assessment of whether those observed levels could be met on a
continuous basis, and the CAA and its legislative history provide no
support in deviating from the general practice EPA has followed in the
wake of NLA I. In a report on H.R. 3030, the House Committee on Energy
and Commerce explained that ``MACT is not intended to require unsafe
control measures, or to drive sources to the brink of shutdown.'' (See
H.R. Rep. No. 101-490, pt. 1, at 328 (1990).) This view is consistent
with NLA I, which involved challenges to standards EPA promulgated
under section 111 of the CAA and is particularly applicable to the
HMIWI rulemaking under CAA section 129, since this rule has its basis
in authority in both section 129 and section 111. (See CAA section
129(a)(1)(A) and (C).)
Moreover, interpreting CAA section 129 as subject to the principles
of NLA I appropriately notes the critical distinction between a level
of emissions that has been continuously achieved through performance
using control technology, and one that has been observed at a single
point in time. A level that has been continuously achieved is capable
of being met under most conditions which can reasonably be expected to
recur because variability in operating conditions is taken into
account. Such a level best effectuates Congress' intent because it
ensures that the MACT floor will result in reduced emissions without
forcing sources to shut down. A lowest observed emission level,
however, is not representative of a unit's performance under most
conditions which can reasonably be expected, and may be impossible to
achieve on a regular, let alone continuous, basis. While an observed
lowest emissions level may be appropriate for use in determining
whether a source is in compliance with an emission standard that must
be continuously met, it is not an appropriate level upon which to base
the minimum stringency level of such a standard.
In addition, Congress' use of the phrases ``as determined by the
Administrator'' and ``achieved in practice'' in CAA section 129(a)(2)
in the directive to establish MACT floors shows that Congress expected
EPA to consider variability in operating conditions and other relevant
factors in the Agency's determinations. The term ``practice'' is
defined as ``[r]epeated or customary action; habitual performance; a
succession of acts of a similar kind; custom; usage.'' (See Black's Law
Dictionary 1172 (6th ed. 1990).) Thus, achieved in ``practice'' means
achieved on a repeated, customary, or habitual basis. Under the
statutory mandate that the level ``achieved in practice'' be
``determined by the Administrator,'' EPA must exercise its judgment,
based on an evaluation of the relevant factors and available data, to
determine the level of emissions control that can be customarily
achieved using the relied-upon technology under variable conditions.
Merely locating the lowest emissions data point and setting the MACT
standard at that level would not constitute a considered
``determination by the Administrator'' as to what has been ``achieved
in practice.'' (See, e.g., Senate Debate on Conference Report, 10-26-
90, reprinted in I A Legislative History of CAA Amendments of 1990,
103d Cong., 1st Sess. at 1128-1129 (Comm. Print 1993) (exchange between
Senators Dole and Durenberger confirming that the phrase ``achieved in
practice'' accounts for the distinction between research-type pollution
control systems and systems that are ``economically viable for
widespread use,'' and stressing that MACT floors should rely upon
technologies that can ``stand the rigors of day to day operations'').)
Ultimately, NLA I is controlling because the case addressed how
standards must be set in the face of variable operating conditions, and
involved one of the same provisions of the CAA, section 111, under
which the HMIWI rule was promulgated. NLA I held that EPA is required
to use data that is representative of emissions that could be achieved
in the industry as a whole. (See 627 F.2d at 433.) In developing the
standards at issue in that case, EPA relied upon tests of the emissions
from particular units to determine the level of emissions control that
was achievable across the entire industry. The Court directed EPA to
identify ``variable conditions that may contribute substantially to the
amount of emissions, or otherwise affect the efficiency of the
emissions control systems.'' Id. The Court then stated that ``where
test results are relied upon, it should involve the selection or use of
test results in a manner which provides some assurance of the
achievability of the standard for the industry as a whole, given the
range of variable factors found relevant to the standards'
achievability.'' Id. This does not mean that EPA must test every plant,
but it does mean that ``due consideration must be given to the possible
impact on emissions of recognized variations in operations and some
rationale offered for the achievability of the promulgated standards
given the tests conducted and the relevant variables identified.'' Id.,
at 434. Thus, applying NLA I to the HMIWI rule adopted under CAA
sections 111 and 129, it is really a misnomer to characterize EPA as
basing the MACT floor on the emissions of the ``worst performing'' unit
using the technology in question, since that unit's level of emissions
necessarily more closely represents the level ``achieved in practice''
by the given technology than would the lowest emissions level observed
at a source using that ``best'' technology.
b. Variability Between Facilities or Units. In remanding the NSPS
at issue in NLA I, the Court noted that its decisions under CAA section
111 ``evince a concern that variables be accounted for, that the
representativeness of test conditions be [sic] ascertained, that the
validity of tests be assured and the statistical significance of
results be determined.'' (See NLA I, 627 F.2d at 452-53.) (See, also,
Portland Cement Ass'n v. Ruckelshaus, 486 F.2d 375, 396 (D.C. Cir.
1973), cert. denied, 417 U.S. 921 (1974).) When floors and standards
are developed based on emissions data, EPA accounts for several types
of variability to avoid adopting unachievable standards. The first type
of variability is that concerning operational distinctions between
facilities or units. As the Sierra Club Court stated in reviewing the
HMIWI rule, ``[p]erhaps considering all units with the same technology
is justifiable because the best way to predict the worst reasonably
foreseeable performance of the best unit with the available data is to
look at other units' performance. Or perhaps EPA reasonably considered
all units with the same technology equally `well-controlled,' so that
each unit with the best technology is a `best-controlled unit' even if
such units vary widely in performance.'' (See 167 F.3d at 665.) These
are two ways of saying essentially the same thing, and these concepts
have
[[Page 5523]]
been used by EPA throughout most of the Agency's history in determining
achievable technology-based emission limitations, in cases where
application of control technology significantly controls emissions and
no record evidence indicates that factors other than the control have
more than a negligible effect. Examining multiple units using the same
technology gives the best picture of the performance capability of that
particular technology, since it provides EPA with a more complete set
of data by which to evaluate what levels of emissions control a
technology can achieve as it is applied to varying sources. Such an
analysis is necessary especially when adopting standards that all
sources in a category will have to be able to meet by using the
identified technology. Since MACT floors and standards are generally
expressed as numerical emissions limits, it is necessary to account for
this variability in order to adopt a regulation that is `achievable' by
the industry as a whole.'' (See NLA I, 627 F.2d at 437.)
Section 129(a)(2) of the CAA requires that EPA determine the
emissions control achieved by the ``best controlled similar unit'' when
establishing the MACT floors for new units. A solid waste incineration
``unit'' is defined as ``a distinct operating unit of any facility
which combusts any solid waste material'' (CAA section 129(g)(1)). To
achieve the best level of pollution control, that unit will utilize a
particular method of pollution control (and possibly use other means
that affect its emissions performance). The emissions control achieved
by that method (and by any additional means) is the emissions control
achieved by the ``best controlled similar unit.'' Thus, the MACT floor
for new units is based on the ``emissions control'' that is attained by
the specific method of pollution control and any other means used to
limit emissions at the best similar unit, rather than merely on the
emissions measured at a particular unit.
In this way, by basing the MACT floor on the capability of a
particular method of pollution control used at ``similar'' ``best''
``units,'' instead of on the emissions measured at a single unit, EPA
ensures that the floors would not only be achievable by the single best
performing unit, but are also achievable by other units using the same
technology and/or emissions limiting means as the best similar unit,
and that it is reasonable to require the best similar unit and all
future new units to meet this floor on a continuous basis. In contrast,
identifying the ``emissions control'' of the ``best controlled similar
unit'' as being a single data point from a single source provides
merely a snapshot of emissions performance that may not be replicable
by either that single source or by other sources using the same control
technology, and, therefore, does not provide a basis for enforceably
requiring all sources to perform to that level.
Thus, the most reasonable way to interpret the statutory phrase
``best controlled similar unit'' in CAA section 129 is as encompassing
all units using the same technology and emissions limiting means as the
single unit with the best observed performance, rather than just that
single best performing unit itself. A contrary interpretation would
seem to directly conflict with the Court's directive in NLA I, and is
not compelled by the Court rulings in Sierra Club, NLA II, and CKRC.
Applying this approach to evaluating ``best technologies'' at ``best
controlled similar units,'' where different design characteristics are
identified (e.g., low-efficiency versus moderate-efficiency versus
high-efficiency wet scrubbers), the data are grouped such that each
data set reflects the performance of an ``identical'' control device,
providing the best indication of the true performance of each control
device and enabling the Agency to adopt a numerical standard that can
be met with the subject technology at all units employing this
technology, and can be enforced. Again, where the record evidence
indicates that the only means of control of emissions at units is
application of control technology, and there is no record evidence
showing that other means of emissions limitation significantly affect
emissions performance, basing the MACT floor on this approach is fully
consistent with the Court's rulings in the MACT cases.
c. Variability Between and Within Tests at Facilities. Another type
of variability that EPA accounts for in order to ensure the
achievability of technology-based standards that rely upon application
of pollution controls concerns operational distinctions between and
within tests at the same unit. Regarding ``between-test variability,''
even where conditions appear to be the same when two or more tests are
conducted, variations in emissions are often caused by different
settings for emissions testing equipment and differences in sample
handling. Varying results may also be caused by use of different field
teams to conduct the testing, or different laboratories to analyze the
results. All these variations are typical.
An achievable standard needs to account for these differences
between tests, in order for ``a uniform standard [to] be capable of
being met under most adverse conditions which can reasonably be
expected to recur[.]'' (See NLA I, 627 F.2d at 431, n. 46.) (See also
Portland Cement Ass'n, 486 F.2d at 396 (noting industry point that ``a
single test offered a weak basis'' for inferring that plants could meet
the standards).) Without accounting for variation among different
emissions tests, it can be determined with a significant degree of
statistical confidence that even a single unit will not be able to meet
the standard over a reasonable period of time, when one can expect
adverse conditions to recur. The Courts have recognized this basic
principle in reviewing technology-based effluent standards under the
Clean Water Act. As the U.S. Court of Appeals for the 5th Circuit
stressed regarding ``best practicable technology'' or ``BPT'' standards
under section 304(b)(1) of the Clean Water Act, ``[t]he same plant
using the same treatment method to remove the same toxic does not
always achieve the same result. Tests conducted one day may show a
different concentration of the same toxic than are shown by the same
test on the next day. This variability may be due to the inherent
inaccuracy of analytical testing, i.e., `analytical variability,' or to
routine fluctuations in a plant's treatment performance.'' (See
Chemical Mf'rs Ass'n v. EPA, 870 F.2d 177, 228 (5th Cir. 1989).) (See
also American Petroleum Institute v. EPA, 540 F.2d 1023, 1035-36 (10th
Cir. 1976) (``Even in the best treatment systems, changes occur in
ability to treat wastes. [* * *] [V]ariability factors present[] a
practical effort to accommodate for variations in plant operations'');
FMC Corp. v. Train, 539 F.2d 973, 985 (4th Cir. 1976) (variability
factors account for ``the fact that even in the best treatment systems
changes continually occur in the treatability of wastes'').)
The same types of differences leading to between-test variability
also cause variations in results between various runs comprising a
single test, or ``within-test variability.'' A single test at a unit
usually includes at least three separate test runs. (See 40 CFR
63.7(e)(3) (for MACT standards under section 112 of the CAA), and 40
CFR 60.8(f) (for NSPS under CAA section 111).) (See also Portland
Cement Ass'n, 486 F.2d at 397 (noting differences in conditions among
several test runs).)
d. Application of NLA I, Sierra Club, NLA II, and CKRC Principles
in HMIWI Rulemaking. Based on the record for the 1997 rulemaking, the
best way to determine the worst reasonably foreseeable circumstances
for the
[[Page 5524]]
particular technologies used to control emissions at HMIWI was to first
examine the highest data point actually observed from HMIWI equipped
with each particular technology. If an emission value has been observed
and there is no reason to believe it represents poor performance (i.e.,
there is nothing that can be done to prevent its recurring), it is
likely to occur again in the future and, therefore, reflects a
foreseeable circumstance. It is incorrect to characterize the highest
data point as the ``worst performance'' of the best performing unit, or
to characterize one control device's performance as ``better'' than
another's based solely on the results of a single emission test. This
is because such focuses relate to essentially random single data
occurrences, rather than to estimating what a particular technology can
be expected to continuously achieve. Rather, each data point, whether
from one unit or from several identical units using the same
technology, should be viewed as a snapshot of the actual performance of
the technology in use. Along with an understanding of the factors
affecting the performance of the technology, each of these snapshots
gives information about the normal, and unavoidable, variation in
emissions that would be expected to recur over time when using the
identified technology. Conversely, when there is evidence that an
emission data point reflects poor performance (design, operation, or
both), such a data point should not be considered in determining the
achievable emission limitation associated with the technology.
Furthermore, a distinction must be made between an emission level
that has been ``observed'' and an emission limitation that can be
continuously ``achieved.'' The purpose of the MACT program is to compel
sources to replicate emission reduction strategies used by the best-
performing sources. Thus, MACT floors are based on the control
strategies used by the best-performing sources to reduce emissions, not
based on a snapshot level of emissions from sources without regard to
whether this level reflects application of any replicable emission
control strategies. CAA section 129(a)(2) does not direct EPA to assess
relative emission ``levels'' in determining MACT floors; it directs EPA
to assess the degree of emissions ``control'' or ``reduction'' or
``limitation'' ``achieved'' by the best-controlled or best-performing
sources. The plain meaning of these words implies that a source is
utilizing some method or technique to reduce emissions that is within a
source operator's power to adopt. The reference to a ``degree of
reduction'' supports the view that the words ``control'' and
``limitation'' appearing in section 129(a)(2) require a source to have
reduced emissions from uncontrolled levels through some control
technique. See NLA II, 233 F.3d at 631-32 (rejecting position that EPA
is required to set new source floors at the lowest recorded emission
level for which it has data and to set existing source floors at the
average of the lowest 12 percent or recorded emission level data
points).
The Court has recognized that EPA may consider variability in
estimating the degree of emission reduction achieved by best-performing
sources and in setting MACT floors. See Mossville Envt'l Action Now v.
EPA, 370 F.3d 1232, 1241-42 (D.C. Cir 2004) (holding EPA may consider
emission variability in estimating performance achieved by best-
performing sources and may set floor at level that best-performing
source can expect to meet ``every day and under all operating
conditions''). Since an emission limitation must be complied with at
all times, for it to be achievable it must be set at a level that will
not force sources to violate it when operating conditions are not ideal
and higher emissions levels might be observed. For example, a car which
has been observed to consume 0.02 gallons of gasoline in a one-mile
downhill stretch of highway cannot be said to have ``achieved'' a
minimum 50 miles per gallon fuel efficiency rate when that same car is
later certain to consume 0.04 gallons of gasoline in a one-mile uphill
stretch of highway (25 miles per gallon). Rather, the minimum fuel
efficiency of the car will be that which the car can meet in adverse
circumstances, the uphill stretch. So it is with emissions limitations,
which cannot reasonably be set at levels which would force sources to
operate in violation even when properly employing the control
technology upon which the standards are based.
The emission data used to develop the emission limitations in the
HMIWI regulations reflect properly designed and operated air pollution
control technology on properly designed and operated HMIWI, and
emission data that reflected poor operation of the HMIWI unit or the
air pollution control technology were excluded. (See Legacy Docket ID
No. A-91-61, items II-A-111 and IV-B-14.) The incinerators selected by
EPA for testing represented a range of incinerator designs and air
pollution control systems in use on this source category. (See Legacy
Docket ID No. A-91-61, item IV-B-46.) The incinerators and air
pollution controls were inspected thoroughly, and maintenance was
performed where necessary to ensure that the incinerators and pollution
controls were functioning properly. (See Legacy Docket ID No. A-91-61,
items II-A-93, II-A-94, and II-A-85.) During testing, most test runs
were conducted under representative conditions to minimize emissions.
(See Legacy Docket ID No. A-91-61, items II-A-111, IV-B-46, and IV-B-
47.) However, some test runs were purposely conducted under conditions
that would represent poor operation (e.g., overcharging waste to the
incinerator) to determine the effect of improper operation on
emissions. (See Legacy Docket ID No. A-91-61, items II-A-111 and IV-B-
46.) These test runs demonstrated that improper operation results in
higher emissions. (See Legacy Docket ID No. A-91-61, items II-A-111,
IV-B-46, and II-A-81.) Of course, the test runs reflecting poor
operation were not used in developing the achievable emission
limitations. Id. It is important to note that such poor operation is
precluded by the good combustion requirements and the parametric
monitoring requirements in the 1997 final rule. In addition to data
gathered by EPA directly, vendors of air pollution control systems
submitted test reports to EPA. (See Legacy Docket ID No. A-91-61, items
II-I-230 through 237, II-I-243 and 244, II-I-248, IV-B-48 and 49, IV-J-
11, IV-J-15 and 16, IV-J-20, IV-J-24, IV-J-27, IV-J-29 through 31, IV-
J-33 and 34, IV-J-39 and 40, and IV-J-47.) The test reports were
submitted primarily by wet scrubber vendors to demonstrate to EPA that
wet scrubbers could achieve lower emissions than EPA had concluded from
the EPA-collected data. (EPA had conducted testing on only one wet
scrubber system.) (See 61 FR 31742; Legacy Docket ID No. A-91-61, item
IV-B-48.) The test reports and the data collected by EPA reflect the
best performance of the air pollution controls that can reasonably be
expected when continuously applied on HMIWI.
MACT and other technology-based standards are necessarily derived
from short-term emissions test data, but such data are not
representative of the range of operating conditions that facilities
face on a day-to-day basis. In statistical terms, each test produces a
limited data sample, not a complete enumeration of the available data
for performance of the unit over a long period of time. (See Natrella,
Experimental Statistics, National Bureau of Standards Handbook 91,
chapter 1 (revised ed., 1966).) EPA, therefore, often needs to adjust
the
[[Page 5525]]
short-term data to account for these varying conditions, so facilities
properly employing optimal controls can remain in compliance with the
standards on a continuous basis.
With the relatively small data sets EPA had to work with in the
1997 HMIWI rulemaking, it is possible that EPA has not recorded the
highest emissions levels that would occur under the worst reasonably
foreseeable circumstances. As the Court noted, it would ``generally
defer to an agency's decision to proceed on the basis of imperfect
scientific information, rather than to `invest the resources to conduct
the perfect study.' '' (See Sierra Club, 167 F.3d at 662.) ``[S]ince
EPA had data on only one percent of about 3,000 [HMIWI], the data
gathering costs of any non-sampling method may well have been
daunting.'' Id., at 663. In fact, the ``perfect study'' cannot be
conducted, regardless of the resources expended to conduct it. Every
study ends with some uncertainty in the results. There is no
``cookbook'' methodology for determining achievable emission
limitations from data. In every case, but especially in cases where
data are limited as with the 1997 HMIWI rulemaking, EPA must make
judgments about what constitutes the worst reasonably foreseeable
circumstance and put those judgments out for public comment. In the
case of the HMIWI rulemaking, the ``high'' data points simply reflected
the normal, and unavoidable, variation in emissions that would be
expected to recur over time when properly using the best control
technologies and strategies we determined were being used at HMIWI
units. In fact, while the highest observed value is a ``foreseeable
circumstance,'' it may not reflect the worst reasonably foreseeable
circumstance. In determining the 1997 final MACT standards, EPA chose
to account for the ``worst reasonably foreseeable circumstance'' by
adding 10 percent to the highest observed emissions levels in the data,
and then rounding up those figures. Upon review of this approach in
responding to the Court's remand, we have determined that although the
highest observed data point may not reflect the ``worst reasonably
foreseeable circumstance,'' we do not have information to support
accounting for the ``worst reasonably foreseeable circumstance'' by
adding 10 percent to the highest observed emissions levels, and then
rounding up those figures. We, therefore, propose to base revised MACT
standards for new HMIWI units on the highest observed data points
associated with employed control strategies.
In the CKRC case, the Court left open the possibility that the
approach of basing floors on the ``worst-performing MACT sources''
emissions represent `a reasonable estimate of the performance of the
[best-performing] units,' '' CKRC at 866, quoting Sierra Club at 662,
provided that ``in the case of a particular source category or HAP, the
Agency can demonstrate with substantial evidence--not mere assertions--
that MACT technology significantly controls emissions, or that factors
other than the control have a negligible effect[.] CKRC at 866, citing
NLA II at 633. The Court in Sierra Club essentially already found this
to be the situation for the HMIWI rulemaking, and it was, therefore,
appropriate for EPA to base its MACT floor review in the 1997 rule
strictly on the emissions reductions achieved by use of control
technologies. The Sierra Club had claimed that EPA wrongly failed to
require HMIWI units to undertake programs to reduce the Hg and
chlorinated plastics in HMIWI waste streams. Sierra Club, at 666. While
the petitioner raised this objection in its challenge to the
promulgated standards, rather than its objection to the floor
methodology, the Court's response to the Sierra Club's claim shows that
in the case of the 1997 HMIWI rulemaking, EPA appropriately focused on
the control technologies used at HMIWI units, and that, therefore,
under the CKRC ruling it was appropriate, in this instance, to base
floors on the highest emissions levels achieved by units employing the
MACT technologies.
The Court observed that ``EPA does not deny that the waste stream
reductions the Sierra Club calls for would reduce pollution. The less
mercury in, the less mercury out, and the less chlorinated plastic in,
the less HCl out. But the EPA has consistently argued in its response
to comments and here that it does not have evidence that allows
quantification of the relevant output reduction. For mercury, the only
quantitative evidence before EPA was that a pollution prevention
program aimed at mercury could reduce mercury emissions from very high
levels to typical levels. See RTC at 7-14 to 7-15. For chlorinated
plastics, there was no quantitative evidence before the agency. See RTC
at 7-16, 7-18. The Sierra Club does not contest the adequacy of EPA's
data-gathering with respect to these measures.'' Id. (Note that the
emission guidelines and NSPS require HMIWI to prepare a waste
management plan under Sec. Sec. 60.35e and 60.55c that would segregate
from the health care waste stream certain solid waste components
contributing to toxic emissions from the incinerator (62 FR 48380,
48387).)
e. Development of the Proposed Revised Emission Limits. While we
are proposing to respond to the Court's remand regarding new units by
basing floors and standards on the same control technologies that
formed the basis for the 1997 standards, in some cases it is necessary
to adjust the emission limits in order to correct for the concerns
regarding our 1997 methodology that the Court raised. As at
promulgation of the 1997 rule, EPA examined the data available for
various air pollution control technologies applied to HMIWI to
determine the performance capabilities of the technologies; identified
the best control technology for each air pollutant for each subcategory
of HMIWI (i.e., MACT floor); considered control technologies more
stringent than the MACT floor; made a determination regarding the
achievable emissions levels from using control technologies upon which
the emission standards would be based; and then established numerical
emission limits achievable with those technologies. The proposed
revised standards are based on the same technologies upon which the
1997 final standards were based--good combustion and a moderate-
efficiency wet scrubber for new small HMIWI, and good combustion and a
combined dry/wet control system with carbon for new medium and large
HMIWI--and reflect the MACT floor emissions levels for new small and
large HMIWI, but are more stringent than the MACT floor for new medium
HMIWI. The rationale for these determinations regarding identification
of MACT can be found at 62 FR 48365.
As explained earlier in this preamble, we are proposing emission
limits for each air pollutant for each subcategory of new HMIWI based
on the highest observed data points associated with the control
technologies upon which the emission standards are based, since we
identified the ``best controlled similar unit'' as one using the
relevant control technologies for each subcategory of new units. The
proposed percent reduction limits for HCl, Pb, Cd, and Hg were
established based on average combustion-controlled emissions estimates
and highest observed data points associated with the control
technologies upon which the emission standards for each of these
pollutants for each subcategory are based. This is the same approach
used at the time of promulgation with two exceptions--the proposed
percent reduction limits do not include the addition of 10 percent
[[Page 5526]]
to the highest observed emissions levels, nor does it include the
rounding up of those figures. A summary of the control technologies
upon which the proposed standards for new HMIWI are based, the highest
observed data points associated with those control technologies, and
the proposed emission limits for new HMIWI in response to the remand
are presented in Table 6 of this preamble. Note that MACT for
NOX and SO2 are ``combustion control,'' although
combustion control results in no emission reductions for those
pollutants because NOX emissions are not reduced by
combustion control, and NOX add-on controls have not been
demonstrated on HMIWI; and SO2 emissions are not reduced by
combustion control, and acid gas controls are not effective in reducing
SO2 emissions from HMIWI at the low SO2 levels
associated with HMIWI.
Table 6.--Summary of Remand Response for New HMIWI
--------------------------------------------------------------------------------------------------------------------------------------------------------
Highest
Pollutant (units) Unit Size \1\ MACT observed data Proposed emission limit \2\
point \2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
HCl (ppmv)............................ L, M, S.................. Wet scrubber............ 9.3 15 \3\ or 99% reduction \3\.
CO (ppmv)............................. L, M, S.................. Good combustion......... 32 32.
Pb (mg/dscm).......................... L, M..................... Dry scrubber w/carbon... 0.06 0.060 or 98% reduction \3\.
S........................ Wet scrubber............ 1.1 0.78 \4\ or 71% reduction.
Cd (mg/dscm).......................... L, M..................... Dry scrubber w/carbon... 0.03 0.030 or 93% reduction.
S........................ Wet scrubber............ 0.14 0.11 \4\ or 66% reduction \3\.
Hg (mg/dscm).......................... L, M..................... Dry scrubber w/carbon... 0.45 0.45 or 87% reduction.
S........................ Wet scrubber............ 0.47 0.47 or 87% reduction.
PM (gr/dscf).......................... L, M..................... Dry scrubber w/carbon... 0.009 0.0090.
S........................ Moderate-efficiency wet 0.018 0.018.
scrubber.
CDD/CDF, total (ng/dscm).............. L, M..................... Dry scrubber w/carbon... 20 20.
S........................ Wet scrubber............ 111 111.
CDD/CDF, TEQ (ng/dscm)................ L, M..................... Dry scrubber w/carbon... 0.53 0.53.
S........................ Wet scrubber............ 2.1 2.1.
NOX (ppmv)............................ L, M, S.................. Combustion Control \5\.. 225 225.
SO2 (ppmv)............................ L, M, S.................. Combustion Control \5\.. 46 46.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ L = Large; M = Medium; S = Small.
\2\ All values are measured at 7 percent oxygen.
\3\ No change proposed.
\4\ Remand standards for existing small non-rural HMIWI are proposed.
\5\ Combustion control results in no emissions reduction.
Note that no change is proposed for the emission limit for HCl for
new large, medium, and small HMIWI. In this situation, the highest
observed emission point (i.e., 9.3 ppmv) is not used as a basis for the
proposed emission limits. Public comments concerning use of EPA Method
26A when testing for HCl emissions at sources with wet scrubbers were
submitted with respect to the recently promulgated standards for other
solid waste incineration units (70 FR 74870, December 16, 2005). The
commenter asserted that EPA Method 26A is not adequate for
demonstrating compliance with an HCl standard below 20 ppmv when
sampling sources with wet scrubbers. Although EPA did not concede that
there is an outright problem, we acknowledged that a tester may need to
take certain precautions to ensure that there is no bias when sampling
streams with low HCl concentrations in certain environments and
promulgated an HCl emission limit of 15 ppmv (versus the proposed limit
of 3.7 ppmv). Method 26A also notes that there is a possible measurable
negative bias below 20 ppmv HCl perhaps due to reaction with small
amounts of moisture in the probe and filter (40 CFR part 60, appendix
A). Accordingly, because many of the wet-scrubber controlled HMIWI used
Method 26A to measure HCl emissions below 20 ppmv and did not take
precautions to ensure no negative bias, in this action we are proposing
to retain the emission limit of 15 ppmv and also are including
provisions that require sources to condition the filter before testing,
and use a cyclone and post test purge if water droplets may be present.
In the cases of Pb and Cd for new small HMIWI, using the highest
observed data points would result in emission limits less stringent
(i.e., higher) than the proposed emission limits for existing small
non-rural HMIWI. Because the existing source analysis provides limits
that can be achieved by existing HMIWI, there is no reason to believe
that new HMIWI could not also meet the more stringent limits. This
unanticipated result may be due to the small amount of Pb and Cd
emissions data available for wet scrubbers at promulgation. Regardless,
we are proposing emission limits for Pb and Cd for new small HMIWI that
are the same as those proposed for existing small non-rural HMIWI.
2. Existing Units
The Court raised three specific concerns regarding EPA's approach
for existing units in concluding that EPA had not adequately explained
why the combination of regulatory and uncontrolled (i.e., combustion-
controlled) data provided a ``reasonable estimate'' of HMIWI
performance: ``First, EPA has said nothing about the possibility that
[HMIWI] might be substantially overachieving the [regulatory] limits.
[Footnote:] Although the agency conceded in its response to comments
that `actual emission data routinely fall below the State permit
emission limits,' [* * *] the context makes reasonably clear that the
EPA was referring to data on `actual emissions' during tests; EPA
implied that `these levels are not routinely achieved in practice.' [*
* *] [End Footnote] If this were the case, the permit limits would be
of little value in estimating the top 12 percent of [HMIWI]s'
performance'' (167 F.3d at 663, and at n. 3). According to the Court,
``[d]ata in the record suggest that the regulatory limits are in fact
much higher than emissions that units achieve in practice.'' Id., at
663.
``Second, EPA never gave any reason for its apparent belief that
[HMIWI]s that were not subject to [regulatory limits] did not employ
emission controls of any sort. Unless there is some finding to this
effect, it is difficult to see the rationality in using `uncontrolled'
data for the units that
[[Page 5527]]
were not subject to regulatory requirements'' (167 F.3d at 664). The
Court pointed out that ``[d]ata submitted by the American Hospital
Association [AHA] in 1995 indicate that over 55% of [HMIWI]s in each
category were controlled by wet scrubbers.'' Id., footnote omitted. As
a result, the Court found it ``difficult to see how it was rational to
include any uncontrolled [i.e., combustion-controlled] units in the top
12 percent, at least with respect to pollutants that wet scrubbing
controls.'' Id.
Third, the Court held that ``assuming the regulatory data was a
good proxy for the better controlled units and that there were
shortfalls in reaching the necessary 12 percent, EPA has never
explained why it made sense to use the highest of its test run data to
make up the gap.'' Id.
Subsequent court decisions also addressed the type of information
EPA may use to estimate emissions performance and establish MACT floors
for existing units. In NLA II, the Court rejected the Sierra Club's
claim that it was unreasonable for EPA to select ``the median
[performing] plant out of the best twelve percent of the plants for
which it had information and set the * * * floor at the level of the
worst performing plant in its databases using th[e same] technology [as
the median plant].'' 233 F.3d at 630. As long as EPA's estimate of the
performance of the top 12 percent was reasonable, the Court held, EPA
was not required to use actual emissions data. Id. While in CKRC the
Court held that EPA had not justified in the HWC rulemaking basing the
floor on emissions levels of the worst performing plant utilizing MACT
control technology, when record evidence indicated other factors beyond
MACT technology affected emissions performance, the Court reiterated
that EPA could use estimates, as long as they reflected a
``reasonable[] estimate [of] the performance of the * * * best-
performing plants.'' 255 F.3d at 862.
Specifically regarding the use of State permits to determine MACT
floors, the Court in Northeast Maryland Waste Disposal Authority v.
EPA, 358 F.3d 936 (D.C. Cir. 2004) (``NMWDA''), rejected EPA's approach
for small municipal waste combustion units because ``as in Sierra Club,
EPA stated only that it `believes' state permit limits reasonably
reflect the actual performance of the best performing units without
explaining why this is so.'' 358 F.3d at 954. There, EPA had asserted
that the inherent variability of emission levels made other data
inaccurate, but the Court concluded that EPA gave ``no evidence that
the [State] permit levels reflect the emission levels of the best-
performing'' units, and that EPA's stated ``belief'' did not rise to
the level of a ``reasonable estimate.'' Id. However, in Mossville
Envt'l Action Now v. EPA (370 F.3d 1232 (D.C. Cir. 2004)), the Court
concluded that ``instead of simply claiming that it believes its
[relied upon] standards estimate what the best five plants actually
achieve, EPA points to some evidence. In its response to comments, EPA
cited its analysis of three years of data, and * * * met its burden of
establishing that its standards reasonably estimate the performance of
the best five performing sources. Having cited the great variability of
emission levels, even within the same plants, and the inherent
difficulty in other standards it considered, the EPA's selection of the
[relevant] standards as the MACT floor is reasonable because it has
supported its decision with record data that shows the connection
between its MACT floor and the top performing plants.'' 370 F.3d at
1242.
a. The Possibility that HMIWI Sources are Substantially
Overachieving their Regulatory Limits. With regard to the Sierra Club
Court's first concern, the Court itself noted early in its opinion that
``the necessary relationship [of regulatory data serving as a
reasonable proxy to indicate HMIWI performance] seems quite reasonable
here. Indeed, it seems likely that any jurisdiction bothering to impose
limits would not knowingly set them below what it found firms to be
achieving in practice. And there seems no reason to think that
underachieving firms would be overrepresented in jurisdictions making
this effort.'' 167 F.3d at 662. The Court also expressed support for
the notion that, when faced with limited actual emissions information,
a substitute `` `reasonable sample' may be used `to find out what the
best 12 percent are doing[,]' '' (id., citing Oral Arg. Tr. at 11), and
that ``EPA typically has wide latitude in determining the extent of
data-gathering necessary to solve a problem.'' Id. Specifically, the
Court noted ``that since EPA had data on only one percent of about 3000
[HMIWI]s, [* * *] the data-gathering costs of any non-sampling method
may well have been daunting.'' Id., at 663.
There are three reasons why EPA chose to use the regulatory limits
at their face value in calculating the existing source MACT floor for
the 1997 rule. First, regulatory data were used because there was very
little actual emissions data available and very little data available
indicating the type of air pollution control used by the best
performing units. (See 61 FR at 31738.) None of the available
information indicated that the regulated entities were substantially
overachieving or underachieving their regulatory limits. Second, there
was no information before the Agency suggesting that the State
regulatory agencies erred in establishing the regulatory limits or that
the States' regulatory limits were outdated. It was thus reasonable for
EPA to expect that the State regulatory limits provided a reasonable
estimate of the actual performance of HMIWI units. Third, it was
reasonable for EPA to expect that regulated entities take their
regulatory limits into account when designing their control equipment.
To some extent, control equipment can be designed to meet various
levels of emissions, and regulated entities do not normally spend more
money than necessary to meet a regulatory limit. As noted above, the
Court observed that ``there seems no reason to think that
underachieving firms would be overrepresented'' by regulatory limits
(167 F.3d at 662). Conversely, there is no reason to generally assume
that substantially overachieving firms would be overrepresented in
jurisdictions imposing regulatory limits. Rather, what is most likely
is that sources in regulated jurisdictions will have assessed whether
steps to control emissions are needed to comply with the regulatory
limits, and that, in order to account for emissions variability when
applying control technologies, they will be targeting their emissions
levels at some safe point below the regulatory limits. Hence, with no
information in the 1997 rulemaking record to indicate otherwise, EPA
generally expected that regulatory limits were being achieved, through
application of emissions control methods, at emissions levels that
sources deem necessary in order to minimize the risk of violating the
relevant limit, and were neither substantially overachieving the limits
nor underachieving them.
The Court noted that the administrative record indicated that, in
some cases, sources were overachieving their regulatory limits, where
the floors based on the weighted average of the regulatory limits and
the ``uncontrolled'' (i.e., combustion-controlled) data were
significantly higher than the values used for combustion-controlled
data. (See 167 F.3d at 663, citing A-91-61, IV-B-024 at 2-3). Here, the
Court was referring to some regulatory limits that, in fact, reflected
higher emissions levels than did EPA's uncontrolled (i.e., combustion-
controlled) emission estimates, and suggested that in these cases it
would be unreasonable for EPA to view the best performing 12 percent
[[Page 5528]]
of sources as actually polluting at levels so much higher than the test
units for which EPA assumed no emissions controls were in place. Id.,
at 663-664.
EPA agrees that a regulatory limit does not reflect ``actual
performance'' when that limit is higher than the level attributed to
the worst reasonably foreseeable performance of an uncontrolled (i.e.,
combustion-controlled) source. Since the data forming the basis for the
existing source MACT floor must provide a reasonable estimation of the
``actual performance'' of the best performing 12 percent of HMIWI, such
high regulatory limits should not have been included in the best-
performing 12 percent. Therefore, in our re-visiting the MACT floor for
existing HMIWI based on the 1997 record, in situations for which there
is no information in the 1997 record indicating the presence of an add-
on pollution control device (``APCD'') or other use of air pollution
control methods but there are regulatory limits, we propose the
substitution of combustion-controlled data for regulatory limits where
those data reflect lower emissions levels than do regulatory limits
that appear to be unrelated to actual controls. We propose to continue
to use combustion-controlled data in situations for which there is no
information indicating air pollution controls are in use and there are
no regulatory limits.
b. Emission Control on HMIWI Not Subject to Regulatory Limits. The
Court's second concern was that EPA had not made a finding that HMIWI
that were not subject to regulatory requirements did not use emissions
controls of any kind. The Court viewed such a finding as a necessary
prerequisite to using uncontrolled (i.e., combustion-controlled) data
for units not subject to regulatory requirements. This issue can be
partly resolved by correcting a misunderstanding that may have resulted
from our 1997 administrative record. The Court focused on information
submitted in 1995 by the AHA suggesting that ``over 55% of [HMIWI]s in
each category were controlled by wet scrubbers.'' (See 167 F.3d at 664,
citing AHA Comments, Exhibit 3.) Based on its review of the AHA
comments, the Court assumed that under EPA's estimation of the HMIWI
population, more than 12 percent in each category ``would as a matter
of mathematical necessity have to be controlled.'' Id., at 664, n. 8.
The Court then observed that ``it is difficult to see how it was
rational to include any uncontrolled [i.e., combustion-controlled]
units in the top 12 percent, at least with respect to pollutants that
wet scrubbing controls.'' Id., at 664.
With regard to the AHA ``data'' identified by the Court as
indicating 55 percent of HMIWI use wet scrubbers, EPA believes that the
Court was led by this information into assuming that unregulated HMIWI
were in fact applying add-on emissions controls, when the record does
not actually substantiate such an assumption, especially for small
HMIWI. The AHA asserts ``almost all properly designed, operated, and
controlled [HMIWI] can readily meet a particulate emission limit of
0.10 gr/dscf without an [add-on air pollution control] system'' (IV-D-
637, Exhibit 2, emphasis added). The AHA then concludes ``[t]herefore,
it is reasonable that as many as 50 percent of those [HMIWI] having
such an emission limit would be uncontrolled.'' Id. The AHA goes on to
assume that 50 percent of all HMIWI with particulate emission limits of
0.10 gr/dscf or higher are controlled with wet scrubbers, while an even
higher percentage of units with more stringent particulate emission
limits are assumed to be controlled. Id. This is akin to saying that,
because homeowners are generally not required to install wet scrubbers
on fireplaces, it is reasonable to assume that as many as 50 percent of
homes with fireplaces do not have wet scrubbers, while the other 50
percent of home fireplaces are equipped with wet scrubbers. The AHA
makes a basic assumption that at least 50 percent of all HMIWI have wet
scrubbers, no matter what requirements they are subject to. With no
other information to support its assumption, AHA's ``data'' indicating
55 percent of HMIWI are equipped with wet scrubbers is altogether
unreliable. In addition, EPA's documented difficulty in identifying
sources with add-on controls during the development of the HMIWI
emission testing program is in direct conflict with the large number of
controlled sources suggested by the AHA ``data.''
Based on information from various sources in the docket from the
1997 rulemaking, including an AHA HMIWI inventory, we now estimate that
about 32 percent of large, 4 percent of medium, and 1 percent of small
HMIWI at the time of the 1997 rulemaking were equipped with add-on
control systems. Other sources in the 1997 record that provided an
indication of whether or not HMIWI were equipped with add-on air
pollution control and upon which these estimates are based include a
survey of HMIWI in California and New York, air permits from State
regulatory agencies, responses to information collection requests,
telephone contact summaries, HMIWI emissions test reports, and various
inventories. (See Legacy Docket ID No. A-91-61, items IV-J-82, IV-B-07,
II-B-94, II-D-175 through 178, II-I-151, IV-J-89, IV-E-65, IV-E-74, IV-
E-86, and II-B-61; Docket EPA-HQ-OAR-2006-0534, document titled ``List
of Test Reports Used to Identify HMIWI Control Devices''). Our
assessment that few HMIWI were equipped with add-on controls is also
supported by economics in that it would not have made sense for an
HMIWI to be voluntarily equipped with an air pollution control device
that costs one to three or more times as much as the entire HMIWI.
Further supporting our assessment is the fact that the expected outcome
of the regulation (which was not refuted by any commenters), that 50 to
80 percent of existing incinerators (including 100 percent of the small
units) would shut down rather than meet the regulations because those
that chose to meet the regulations would have to install air pollution
control to comply, was, in fact, more than realized. (See 60 FR 10665,
61 FR 31768, and 62 FR 48372.) In fact, all but 8 small units, 6 of
which meet the rural criteria and did not have to install air pollution
control to comply, 20 medium units, and 44 large units have shut down,
rather than meet the standards that would have been achieved by use of
the very controls AHA appeared to assume were in place. Consequently,
EPA concludes that the 1997 record, as confirmed by recent data showing
the vast reduction in sources (as opposed to sources installing
controls), shows that most HMIWI were not equipped with add-on air
pollution control and that the use of uncontrolled (i.e., combustion-
controlled) emission estimates where there was no indication of air
pollution control (and where any applicable regulatory limits allowed
higher levels of emissions than our combustion-controlled emissions
values reflected) was warranted. Based on the number of HMIWI
shutdowns, it appears very likely that there were even fewer HMIWI with
air pollution controls than we estimated based on the information
discussed above (i.e., that about 32 percent of large, 4 percent of
medium, and 1 percent of small HMIWI were equipped with add-on control
systems).
c. EPA's Use of the Highest Emissions Data to Reflect Uncontrolled
(i.e., Combustion-Controlled) Emissions. The Court's third concern
regarded our use of the highest of the test run data to reflect
uncontrolled (i.e., combustion-controlled) emissions in cases where
regulatory data did not comprise the
[[Page 5529]]
necessary 12 percent of best performing sources. Our reason for this
approach is the same as the reason described earlier regarding new
units for using the highest data point from MACT-particular technology
to reflect the performance of that technology and identify the ``best
controlled similar unit.'' As the Court stated in NLA I, ``where test
results are relied upon, it should involve the selection or use of test
results in a manner which provides some assurance of the achievability
of the standard for the industry as a whole, given the range of
variable factors found relevant to the standard's achievability.'' (See
627 F.2d at 433). EPA reads the Court's opinion in Sierra Club as at
least endorsing the principles of NLA I with respect to existing units,
as the Court described as ``counterintuitive'' the Sierra Club's
``proposition that an `achieved' level may not be `achievable[.]' ''
(See 167 F.3d at 662). In addition, we also read CKRC as allowing this
approach, where no evidence in the record contradicts the assumption
that ``factors other than the control have a negligible effect [on
emissions performance],'' 255 F.3d at 866, and, therefore, the presence
or absence of known effective MACT controls is the prime determinant of
emissions performance.
Where regulatory data indicating use of emissions control was
absent in the 1997 rulemaking record, EPA needed to find a surrogate
emission limitation that reflected uncontrolled (i.e., combustion-
controlled) emissions, expecting, when not faced with data indicating
otherwise, that facilities with no regulatory limits would not be
controlling their emissions with add-on controls or other control
methods (beyond combustion control). In this situation, EPA used the
highest test data point from a well-operated HMIWI as a surrogate for
the worst reasonably foreseeable circumstances. The highest test data
points reflect the normal, and unavoidable, variation in emissions that
would be expected to recur over time. Table 7 of this preamble
summarizes the performance values used for units for which there is no
information indicating an APCD is present and there are no regulatory
limits, or where regulatory limits do exist but reflect emissions
levels that are higher than the values for uncontrolled (i.e.,
combustion-controlled) units.
Table 7.--Uncontrolled (i.e., Combustion-Controlled) Performance Values
------------------------------------------------------------------------
Performance
Pollutant (units) value \1\
------------------------------------------------------------------------
HCl (ppmv)............................................... 2,770
CO (ppmv) -.............................................. \1\ 584.9
Pb (micrograms per dry standard cubic meter [mu]g/dscm).. 8,629
Cd ([mu]g/dscm).......................................... 3,520
Hg ([mu]g/dscm).......................................... 6,543.4
PM (gr/dscf)............................................. \2\ 0.278
CDD/CDF, total (ng/dscm)................................. \2\ 8,102
CDD/CDF, TEQ (ng/dscm)................................... \2\ 236
NOX (ppmv)............................................... 224.5
SO2 (ppmv)............................................... 46.39
------------------------------------------------------------------------
\1\ All performance values are measured at 7 percent oxygen.
\2\ Based on 1-second combustion level
d. Determining the MACT Floor and MACT for Existing Units. As
discussed above, the Sierra Club Court identified some potential errors
in EPA's methodology for determining the existing source MACT floors
for HMIWI. After reviewing the 1997 HMIWI record in the context of the
Court's opinion, EPA agrees that, in determining the MACT floor, the
Agency should not have used regulatory limits that reflected higher
emissions levels (and that did not appear to be related to any air
pollution controls) than those corresponding to EPA's combustion-
controlled emission estimates. Furthermore, as we examined the 1997
record and our estimates of the performance of HMIWI where we had some
indication that add-on controls may have been used, we determined that
we should not have used combustion-controlled emission estimates in the
floor calculations to represent the performance of those sources.
Additionally, for this rulemaking we propose that where actual
emissions test data reflecting emissions performance was available in
the 1997 record for use in determining the MACT floor, that data should
take precedence over other types of data (i.e., regulatory limits or
performance values).
EPA's reassessment of the 1997 MACT floors and MACT decisions,
based on an adjusted methodology that addresses the Court's issues
discussed above, results in proposed emission limits that in many cases
are more stringent than the limits promulgated in 1997. EPA's first
step in redoing the MACT analysis based on the 1997 record for existing
HMIWI was to determine the pollutant-specific values that make up the
best performing 12 percent of existing units within each size category.
Actual test data, where available in the 1997 record, were the initial
type of pollutant-specific values considered. Next, where the 1997
record has information indicating that a source employed some type of
add-on control but there are no test data or regulatory limits for that
source, an average of the maximum dry and wet control system
performance was determined for each pollutant, and those values were
added to the data set towards comprising the best performing 12
percent. We believe that use of these averages is an appropriate method
of estimating the performance of HMIWI (1) where the 1997 record has
limited information indicating the presence of some type of add-on
control but no test data for the unit, and (2) where we are unsure if
the control is similar to, or is as efficient as, those for which we
have data, or if the unit even employed a true control device. As
previously stated, we believe it very likely that there were fewer
HMIWI with air pollution controls than we estimated in 1997, and to
which we have assigned pollutant-specific average control device
values. If, in fact, those sources were employing true control devices,
common sense dictates that there wouldn't have been the large number of
unit shut downs that occurred in response to the promulgated standards.
However, because we had some indication that an add-on control device
was in place on those sources, we recognize that the use of
uncontrolled (i.e., combustion-controlled) emission estimates (at
promulgation) did not provide a reasonable estimate of their
performance. Similarly, use of performance values associated with a
specific type of add-on control device seems inappropriate when no
details are available on the control device and there is, in fact, some
doubt as to the presence of a true control device at all. Despite the
doubts of the presence of a true control device, the approach we have
selected assumes that the 1997 record is correct and assigns
``default'' performance values to the units that are based on the
expected performance of the types of control devices used in the
industry in 1997. These default performance values, based on the
average of the maximum dry and wet control system performance, also are
used where regulatory limits exist but are higher than the default
performance values.
Table 8 of this preamble summarizes the performance values for HCl,
Pb, Cd, Hg, CDD/CDF, and PM for units for which the 1997 record has
information indicating that they employed some
[[Page 5530]]
type of add-on control but has no test data or regulatory limits
corresponding to specific controls, or where regulatory limits exist
but are higher than the values based on an average of the maximum dry
and wet control system performance.
Table 8.--Performance Values Based on Average of Maximum Dry and Wet
Control System Performance
------------------------------------------------------------------------
Performance
Pollutant (units) value \1\
------------------------------------------------------------------------
HCl (ppmv)............................................... 53.165
Pb ([mu]g/dscm).......................................... 568.5
Cd ([mu]g/dscm).......................................... 83.65
Hg ([mu]g/dscm).......................................... 459.5
PM (gr/dscf)............................................. 0.0195
CDD/CDF, total (ng/dscm)................................. 65.35
CDD/CDF, TEQ (ng/dscm)................................... 1.296
------------------------------------------------------------------------
\1\ All performance values are measured at 7 percent oxygen.
The values for CO, NOX and SO2 are based on
the performance of combustion-controlled HMIWI because, as stated at
proposal and promulgation of the 1997 HMIWI standards, as well as
earlier in this preamble, CO emission levels are affected by combustion
practices rather than the control systems used by HMIWI; NOX
control had not been demonstrated on HMIWI; and the acid gas controls
used by HMIWI were not effective in reducing SO2 emissions
from HMIWI due to the low inlet levels of SO2 associated
with hospital/medical/infectious waste. Therefore, for units (1) where
the 1997 record contains information indicating that they employed some
type of add-on control but for which there was no test data or
regulatory limits, or (2) where regulatory limits existed but were
higher than the values for CO, NOX, or SO2 based
on combustion-controlled HMIWI, the performance values for CO (584.9
ppmv), NOX (224.5 ppmv), and SO2 (46.39 ppmv) are
the same as those presented in Table 7 of this preamble.
The next step in the MACT analysis for existing HMIWI was to
determine the average emission limitation achieved by the best-
performing 12 percent of existing sources where there are 30 or more
sources in the category or subcategory. Our general approach to
identifying the average emission limitation has been to use a measure
of central tendency, such as the arithmetic mean or the median. If the
median is used when there are at least 30 sources, then the emission
level that is at the bottom of the best performing 6 percent of sources
(i.e., the 94th percentile) represents the MACT floor control level. We
based our MACT floors for each pollutant within each size category on
this approach. We then determined the technology associated with each
``average of the best-performing 12 percent'' value by comparing the
average values to average performance data for wet scrubbers, dry
injection fabric filters (also known as dry scrubbers), and combustion
controls (no add-on air pollution controls). Those pollutants with
average values that were higher than the relevant combustion-controlled
emission estimate were identified as having a ``combustion control''
floor, even if the pollutant is not reduced by combustion control. The
technology needed to meet the remaining average values reflects the
technology used by the average unit in the top 12 percent and serves as
the basis for the MACT floor. EPA then considered, on a pollutant-
specific basis, technologies that were more stringent than the MACT
floor technologies.
Add-on control technology-based MACT floors were identified for
large HMIWI for HCl, Pb, Cd, Hg, PM, and CDD/CDF. The MACT floor
technology for all size units for NOX and SO2 is
``combustion control'' although, as previously explained in this
preamble, combustion control results in no emission reductions for
those pollutants. ``Good combustion'' (i.e., 2-second combustion) was
identified as the MACT floor technology for all size units for CO.
``Combustion control'' floors were identified for medium HMIWI for Pb,
Cd, Hg, and CDD/CDF and for small HMIWI for HCl, Pb, Cd, Hg, and CDD/
CDF. However, for these pollutants for all medium and most small HMIWI,
we have decided to propose limits that are more stringent than the
``combustion control'' floors and are consistent with the control
technology-based MACT floors that were identified for large HMIWI for
these pollutants (i.e., Pb, Cd, Hg, and CDD/CDF for medium HMIWI and
HCl, Pb, Cd, Hg, and CDD/CDF for small HMIWI). The control technologies
identified as the MACT floors for HCl and PM for medium HMIWI, and for
PM for small HMIWI, provide an indication of the level of control of
the other pollutants--a level of technology that is consistent with
those technologies identified for large HMIWI. The rationale for not
basing the proposed emission limits on other technologies that would
result in even more stringent limits can be found at 62 FR 48371-72. As
at the 1997 promulgation, MACT for small HMIWI that meet certain
``rural criteria'' was determined to be at the MACT floor level for
each pollutant (i.e., no ``beyond-the-floor''-based emission limits).
Table 9 of this preamble shows the average emission value, based on
the ranking of emissions data, regulatory data, and performance data,
of each pollutant for the top 12 percent of HMIWI in each subcategory.
The values in Table 9 allow EPA to identify the technology associated
with the average unit in the top 12 percent of HMIWI.
Table 9.-- Average Emission Values for Top 12 Percent of Hmiwi \1\
------------------------------------------------------------------------
HMIWI size
Pollutant (units) -----------------------------------
Small Medium Large
------------------------------------------------------------------------
HCl (ppmv).......................... 2,770 53 50
CO (ppmv)........................... 100 100 100
Pb (mg/dscm)........................ 8.63 8.63 0.569
Cd (mg/dscm)........................ 3.52 3.52 0.084
Hg (mg/dscm)........................ 6.54 4.27 0.460
PM (gr/dscf)........................ 0.080 0.030 0.020
CDD/CDF, total (ng/dscm)............ 8,102 8,102 65.4
CDD/CDF, TEQ (ng/dscm).............. 236 236 1.30
NOX (ppmv).......................... 225 225 225
SO2 (ppmv).......................... 46.4 46.4 46.4
------------------------------------------------------------------------
\1\ All emission values are measured at 7 percent oxygen.
[[Page 5531]]
Table 10 of this preamble shows the technology associated with each
average emission value.
Table 10.--MACT Floor Technology
----------------------------------------------------------------------------------------------------------------
HMIWI Size
Pollutant (units) --------------------------------------------------------------------------
Small Medium Large
----------------------------------------------------------------------------------------------------------------
HCl (ppmv)........................... combustion control..... dry scrubber........... dry scrubber.
CO (ppmv)............................ good combustion........ good combustion........ good combustion.
Pb (mg/dscm)......................... combustion control..... combustion control..... wet scrubber.
Cd (mg/dscm)......................... combustion control..... combustion control..... wet scrubber.
Hg (mg/dscm)......................... combustion control..... combustion control..... dry scrubber.
PM (gr/dscf)......................... low-efficiency wet moderate-efficiency wet moderate-efficiency wet
scrubbber. scrubber. scrubber.
CDD/CDF, total (ng/dscm)............. combustion control..... combustion control..... wet scrubber.
CDD/CDF, TEQ (ng/dscm)............... combustion control..... combustion control..... wet scrubber.
NOX (ppmv)........................... combustion control..... combustion control..... combustion control.
SO2 (ppmv)........................... combustion control..... combustion control..... combustion control.
----------------------------------------------------------------------------------------------------------------
For small units, the CO and PM values indicate that good combustion
control (i.e., 2-second combustion) and a low-efficiency wet scrubber
reflect the CO and PM MACT floors. For medium units, as well as large
units, the CO, HCl, and PM values indicate that good combustion control
used in conjunction with either a dry scrubber or moderate-efficiency
wet scrubber reflects the CO, HCl, and PM MACT floors. As previously
stated, EPA concluded that emission limits for small units that meet
the rural criteria should reflect the MACT floor level of control for
all pollutants. The average emission value and MACT floor level of
control for PM vary by unit size, and we are proposing emission limits
based on those levels of control. The average emission values, and
associated MACT floor levels of control, for CO, NOX, and
SO2 are the same for all size units. For most small units
and all medium units, however, we concluded that emission limits for
HCl, Pb, Cd, Hg, and CDD/CDF should reflect the MACT floor level of
control for large units for those pollutants.
The resulting numerical emission limits were determined by
combining the appropriate average emission value for each pollutant for
each size HMIWI with a variability factor. We believe it is necessary
to account for variability given the limited amount of actual data
available in the 1997 record and the resulting need for use of various,
and often presumptive, types of information to formulate the best
performing 12 percent of HMIWI. At promulgation, we recognized the need
to account for variability and did so as described earlier in this
preamble. Although we maintain that the methodology we used was not
unreasonable given the available information at promulgation, we now
have additional information (the 2002 compliance test data for all of
the currently operating units) for use in calculating pollutant-
specific variability factors. While these data were not available at
promulgation, they are the only data available for providing a
quantitative assessment of variability of emissions from well-
controlled HMIWI. To determine the pollutant-specific variability
factors, a statistical analysis was conducted. Specifically, the
emission limit achievable for each pollutant was determined based on
the combination of actual emissions test data, regulatory data, and
estimated performance levels (as described earlier) and a statistics-
based variability factor calculated for each pollutant. To calculate
the variability factors, we used the general equation: variability
factor = t * standard deviation. This general equation has been used by
EPA in similar analyses. (See, e.g., 68 FR 27650; 69 FR 55235-7; 70 FR
28615.) We selected the 90th percentile confidence level for this one-
sided t-statistics test. The 90th percentile provides a variability
factor appropriate for well-controlled sources that is based on data
from well-controlled sources (i.e., the only sources that are still in
operation).
Table 11 of this preamble presents the values determined by adding
the variability factors to the average emission values for each
pollutant for existing large and medium HMIWI. The table also presents
the proposed revised emission limits for existing large and medium
HMIWI necessary to respond to the Court's remand and the percent
reduction limits for HCl, Pb, Cd, and Hg. The percent reduction limits
are based on average combustion-controlled emissions estimates and
maximum performance values for the MACT identified for each pollutant
for each subcategory. This is the same approach used at the time of
promulgation of the 1997 rule, except that the proposed percent
reduction limits do not include the addition of 10 percent to the
maximum performance values or the rounding up of those figures.
Table 11.--Average Emission Values, Considering Variability, and Emission Limits \1\--Existing Large and Medium
HMIWI
----------------------------------------------------------------------------------------------------------------
Large Medium
---------------------------------------------------------------------------
Pollutant (units) Average + Average +
variability Emission limit variability Emission limit
----------------------------------------------------------------------------------------------------------------
HCl (ppmv).......................... 78 78 or 93% reduction 57.9 78 \3\ or 93%
\2\. reduction \2\.
CO (ppmv)........................... 110 40 \2\................ 113 40 \2\
Pb (mg/dscm)........................ 0.78 0.78 or 71% reduction. 9.02 0.78 \3\ or 71%
reduction \3\.
Cd (mg/dscm)........................ 0.11 0.11 or 66% reduction. 3.56 0.11 \3\ or 66%
reduction \2\.
Hg (mg/dscm)........................ 0.64 0.55 \2\ or 87% 4.34 0.55 \2\ or 87%
reduction. reduction \3\.
PM (gr/dscf)........................ 0.025 0.015 \2\............. 0.043 0.030 \2\
[[Page 5532]]
CDD/CDF, total (ng/dscm)............ 115 115................... 8,150 115 \3\
CDD/CDF, TEQ (ng/dscm).............. 2.16 2.2................... 237 2.2 \3\
NOX (ppmv).......................... 284 250 \2\............... 273 250 \2\
SO2 (ppmv).......................... 61 55 \2\................ 51.8 55 \2\
----------------------------------------------------------------------------------------------------------------
\1\ All emission values are measured at 7 percent oxygen.
\2\ No change from current emission limit.
\3\ Emission limit is the same as that for large HMIWI.
Table 12 of this preamble presents the same information for
existing small non-rural HMIWI and for existing small HMIWI meeting the
rural criteria.
Table 12.-- Average Emission Values, Considering Variability, and Emission Limits \1\--Existing Small And Small
Rural HMIWI
----------------------------------------------------------------------------------------------------------------
Large Medium
----------------------------------------------------------------------
Pollutant (units) Average + Average + Emission
variability Emission limit variability limit
----------------------------------------------------------------------------------------------------------------
HCl (ppmv)............................... 2,772 78 \3\ or 93% reduction 3,125 \2\ 3,100
\2\..
CO (ppmv)................................ 103 40 \2\..................... 109 \2\ 40
Pb (mg/dscm)............................. 8.85 0.78 \3\ or 71% reduction 8.88 8.9
\3\.
Cd (mg/dscm)............................. 3.54 0.11 \3\ or 66% reduction 3.54 4
\2\.
Hg (mg/dscm)............................. 6.55 0.55 \2\ or 87% reduction 6.56 6.6
\3\.
PM (gr/dscf)............................. 0.095 0.050 \2\.................. 0.089 \2\ 0.086
CDD/CDF, total (ng/dscm)................. 8,335 115 \3\.................... 8,518 \2\ 800
CDD/CDF, TEQ (ng/dscm)................... 239 2.2 \3\.................... 244 \2\ 15
NOX (ppmv)............................... 225 250 \2\.................... 273 \2\ 250
SO2 (ppmv)............................... 46.4 55 \2\..................... 51.8 \2\ 55
----------------------------------------------------------------------------------------------------------------
\1\ All emission values are measured at 7 percent oxygen.
\2\ No change from current emission limit.
\3\ Emission limit is the same as that for large HMIWI.
For pollutants where this remand analysis (based on the average of
the best performing 12 percent of HMIWI plus the variability factor)
resulted in emission limits less stringent (i.e., higher) than the
current emission limits, we retained the current emission limits. This
is because we see no reason to upwardly revise standards that the
regulated industry has already demonstrated are achievable based on
compliance data. In fact, now that we have received the 2002 compliance
data for HMIWI units, it is apparent that EPA's estimate of the
achievable emissions performance levels from use of the identified MACT
technology was reasonably accurate. While we are not in this proposal
attempting to justify our prior existing unit MACT floor decisions post
hoc based on new data that we could not have relied upon in the 1997
rulemaking itself, we note that, similar to the Mossville case, we
currently find ourselves in a situation where actual emissions data
fairly confirms our prior estimates of what the best controlled HMIWI
units could achieve when using MACT controls.
The resulting emission limits being proposed for medium HMIWI for
HCl and SO2; for small HMIWI for NOX and
SO2; and for small rural HMIWI for SO2 are the
same as those being proposed for large HMIWI because, in these
instances, the medium, small, and small rural HMIWI are expected to
achieve reductions similar to large HMIWI.
B. Rationale for the Proposed Amendments (CAA Section 129(a)(5) 5-Year
Review)
In recent rulemakings (see, e.g., 71 FR 34422, 34436-38 (June 14,
2006) (proposed amendments to the NESHAP for Hazardous Air Pollutants
for Organic Hazardous Air Pollutants from the Synthetic Organic
Chemical manufacturing Industry)) EPA has addressed the similar
technology review requirement under CAA section 112(d)(6). EPA stated
that the statute provides the Agency with broad discretion to revise
MACT standards as we determine necessary, and to account for a wide
range of relevant factors, including risk. EPA does not interpret such
technology review requirements to require another analysis of MACT
floors for existing and new units, but rather requires us to consider
developments in pollution control in the industry and assess the costs
of potentially stricter standards reflecting those developments. (See,
id., at 34436-47.) Moreover, as a general matter, EPA has stated that
where we determine that existing standards are adequate to protect
public health with an ample margin of safety and prevent adverse
environmental effects, it is unlikely that EPA would revise MACT
standards merely to reflect advances in air pollution control
technology. Id., at 34437-38.
Under CAA section 112(d)(6), the first round of technology review
for MACT standards is subject to the same statutory timeframe as EPA's
residual risk review under CAA section 112(f)(2), with both reviews
occurring 8 years following initial promulgation of MACT. We interpret
CAA section 129(a)(5)'s technology review
[[Page 5533]]
requirement as providing us the same degree of discretion in terms of
whether to revise MACT standards, for the reasons discussed in those
prior rulemakings. (See, id., at 34436-38.) However, the deadline for
the first round of technology review under section 129(a)(5) (5 years
following MACT promulgation) does not coincide with the deadline for
residual risk review under section 112(f)(2) (9 years, in the case of
HMIWI standards). Therefore, this first section 129(a)(5) technology
review for HMIWI does not account for or reflect our residual risk
analysis. In future rounds of review under section 129(a)(5) for the
HMIWI standards, we intend to follow our general policy, and for our
technology reviews and conclusions to be informed by our residual risk
analysis, which we will have performed by that point.
In exercising its discretion under CAA section 129(a)(5), EPA is
proposing in this technology review to adopt emission limits based on
the 2002 data because it believes that these limits represent the cost-
effective operation of the MACT control technology. EPA is aware of the
possibility that regulated units are likely to operate at a level
somewhat below emission standards in order to account for operational
variability. It is not our intent to preclude this practice through
successive rounds of the section 129(a)(5) technology review. EPA
requests comment on its proposal (as outlined below) to adopt more
stringent emission limits in this instance through its section
129(a)(5) technology review.
1. How were the proposed emission limits developed?
The proposed revised emission limits resulting from our 5-year
review of the HMIWI standards under section 129(a)(5) of the CAA are
based on the performance of units within the industry that currently
are subject to the MACT standards. One set of emission limits is
proposed for existing HMIWI regulated under CAA section 111(d)/129(b)
emission guidelines, and another set of emission limits is proposed for
new HMIWI (units commencing construction after February 6, 2007)
regulated under CAA section 111(b)/129(a) NSPS. Units that were subject
to the 1997 NSPS as new units (referred to as ``1997 NSPS units'' for
the remainder of this preamble) will remain subject to the 1997 NSPS
(including revisions resulting from EPA's response to the Court
remand), but will also be subject to any requirements of the revised
emission guidelines that are more stringent than the 1997 NSPS
requirements. The proposed emission limits for existing units, 1997
NSPS units, and new units were developed following the procedures
discussed below.
As background, with one exception resulting from the analyses
associated with our response to the Court remand, the proposed emission
limits for new and existing units are based on the application of the
same control technologies upon which the 1997 MACT standards were
based. For new large and medium units, both the current and proposed
emission limits are based upon good combustion and the application of
combined control systems that include both dry scrubbers (i.e., dry
injection fabric filters or spray dryer fabric filters) with carbon
injection and wet scrubbers. The current and proposed emission limits
for new small units are based on good combustion and the application of
a moderate-efficiency wet scrubber. For large, medium, and most small
existing units, the current and proposed emission limits are based on
good combustion control for CO; combustion controls (i.e., no add-on
controls) for NOX and SO2; and the application of
either dry scrubbers or wet scrubbers (with various ``efficiencies''
depending on the size of the unit) for the remaining pollutants. The
current emission limits for one additional subcategory, existing small
rural units, are based solely on good combustion (i.e., the MACT floor
identified in the 1997 analysis was not based on add-on control
technology). With the exception of PM, the proposed emission limits for
existing small rural units also are based solely on good combustion. In
our remand analysis, we identified a low-efficiency wet scrubber as
being the MACT floor for PM for these units. Although all small rural
units currently use only good combustion, to address this difference in
the MACT floors (i.e., 1997 analysis versus remand analysis), we are
proposing a PM emission limit for existing small rural units based on
the application of low-efficiency wet scrubbers to existing small non-
rural units (i.e., MACT floor for small non-rural units in the 1997
analysis as well as the remand analysis). While this performance level
is associated with the expected performance of a low-efficiency wet
scrubber, the combustion controls in place on these six existing small
rural units achieve this performance level, based on the initial
compliance tests for these units.
In performing this 5-year review, we have not recalculated new MACT
floors, but have proposed to revise the emission limits to reflect the
actual performance of the MACT technologies. We believe this approach
reflects the most reasonable interpretation of the review requirement
of CAA section 129(a)(5), and is consistent with how we have
interpreted the similar review requirement of CAA section 112(d)(6)
regarding MACT standards promulgated under section 112. (See 71 FR
27327-28; 69 FR 48350-51; and 70 FR 20008.) The language of section
129(a)(5) directs EPA to ``review'' our promulgated standards under CAA
section 111/129, and to ``revise such standards and requirements'' ``in
accordance with this section and section 111.'' It does not, however,
direct EPA to conduct, at 5-year-intervals, new MACT floor and beyond-
floor analyses based on each 5-years' changing information as to what
might comprise the top 12 percent of sources or constitute the best
controlled similar unit. There is no indication that Congress intended
for section 129(a)(5) to inexorably force existing source standards
progressively lower and lower in each successive review cycle, the
likely result of requiring successive floor determinations.
Following MACT compliance in September 2002, EPA obtained
compliance test reports from all operating HMIWI (76 units at 70
facilities) and used those data to evaluate MACT performance. When the
HMIWI regulations were first proposed in 1995, re-proposed in 1996, and
promulgated in 1997, only limited information was available about HMIWI
emission controls, and significant engineering judgment was necessary
in selecting the emission limits. The year 2002 compliance data show
that the control technologies that were installed and the practices
that were implemented to meet the 1997 NSPS and emission guidelines
achieved reductions somewhat superior to what we expected under the
1997 limits for many of the pollutants. EPA used the compliance test
data to develop the emission limits contained in the amendments we are
proposing under the 5-year review. EPA believes that the proposed
emission limits more accurately reflect actual real-world HMIWI MACT
performance than what we had estimated in 1997 and what we re-estimated
based on the 1997 record in response to the Court's remand (discussed
previously in this preamble). We believe that it is necessary, as well
as appropriate, to update the 1997 promulgated standards based on the
actual performance of MACT technologies in situations where compliance
test data indicate that the technologies achieve better performance
levels than those we previously
[[Page 5534]]
estimated based on the information available at the time of
promulgation.
a. Existing Units. The first step in the analysis was to assess the
performance of the HMIWI currently subject to the emission guidelines
with respect to each regulated pollutant. We first examined the data
separately for each unit size, and the data showed, for all pollutants
except PM, that the performance of units with add-on controls,
regardless of size, (excluding small rural units, which do not employ
add-on controls), is similar. Therefore, we combined the data,
regardless of unit size, for all of the pollutants except PM, and
conducted analyses on the combined data sets. In addition, for the
pollutants with emission limits based on good combustion and combustion
control (i.e., no add-on controls), namely CO, NOX, and
SO2, the data for small rural units also were combined with
the data for all of the other subcategories of units. Analyses were
performed on each data set, and we calculated the 99 percent upper
tolerance limit (UTL), which is the emission level that 99 percent of
the HMIWI would be expected to achieve. A similar methodology was used
for stack test-based emission limits in the 5-year review recently
conducted for large municipal waste combustors (MWC). In the preamble
to that final action, EPA indicated that analysis of data to estimate
emission limits to be enforced by stack test methods must be done using
a different approach (i.e., lower percent UTL) than where enforcement
is to be based on CEMS and that the percentile must also reflect a
reasonable consideration of emissions variability and compliance
limitations of stack testing (See 71 FR 27329). EPA further indicated
that for this type of technology review, the 99 percent UTL was
appropriate to use as a tool for estimating achievable emission levels
for emission limits enforced by stack testing. Id. In this proposed
rulemaking, the 99 percent UTL was used as the starting point for
selecting the revised emission limits. We compared the 99 percent UTL
values to several other values, including the 1997 promulgated emission
limits and the revised limits that we are proposing in response to the
Court's remand (``remand limits''). For several pollutants, the value
associated with the 99 percent UTL was higher than the remand limit. In
these cases, we selected the remand limit, rather than the 99 percent
UTL value, as the proposed emission limit. We also graphically compared
the 99 percent values and remand limits, where applicable, to all of
the data that were used to calculate the percentile values. In many
cases, this visual comparison revealed that the 99 percent UTL value or
remand limit fell within a break in the data that indicated a level of
performance that the technologies, considering variability, could
readily achieve but that the ``worst performing'' units were not
achieving during their compliance tests. Thus, our analyses indicate
that the emission limits that we selected reflect the actual
performance of the MACT control technologies while also serving to
require modest improvements in performance from units that are not
achieving the performance levels demonstrated in practice by the
control technologies currently being used in the industry.
For small non-rural HMIWI, we used a different methodology for
assessing PM performance because there are only two units and,
therefore, statistics are not a useful tool. Both of the small non-
rural units are equipped with wet scrubbers. Because existing medium
units are predominantly equipped with wet scrubbers, the PM emission
limit developed using the 99 percent UTL value of the data set for
existing medium units also is being proposed for small non-rural units.
A different methodology also was used for assessing performance of
the six small rural HMIWI. To determine the actual performance of these
small combustion-controlled units while considering the inherent
variability in emissions, we obtained test data for all six units
(although, as allowed in the emission guidelines, not all of the
pollutants were tested at every unit) and selected as the emission
limit the highest individual test run from the compliance testing for
HCl, Pb, Cd, Hg, and CDD/CDF. This methodology uses actual test data to
provide a reasonable estimate of the performance of the small rural
units for these pollutants, where statistics are not a useful tool,
while accounting for variability. There are exceptions to this
methodology for CO, NOX, and SO2. As previously
mentioned in this preamble, the CO, NOX, and SO2
data for small rural units were combined with the CO, NOX,
and SO2 data for the other subcategories of units. The 99
percent UTL methodology was then used as the starting point, as
previously described in this preamble, to determine proposed emission
limits that would apply to all of the subcategories of existing HMIWI.
Another exception to this methodology is the proposed emission limit
for PM. As previously explained in this preamble, we are proposing a PM
emission limit for existing small rural units based on the application
of low-efficiency wet scrubbers to existing small non-rural units
(i.e., we are proposing the same PM emission limit for small rural and
non-rural units). While many of the resulting proposed emission limits
for small rural units are significantly more stringent than the 1997
promulgated limits, the proposed limits more accurately reflect the
actual performance of these units.
Finally, we examined the available data for calculating percent
reduction requirements for HCl, Pb, Cd, and Hg. Percent reduction
standards were included in the 1997 promulgated standards for these
pollutants, and we are proposing to update these requirements to
reflect the now-known actual performance of HMIWI utilizing MACT
controls. For HCl, we obtained percent reduction data from five large
HMIWI using dry scrubbers (i.e., the control technology upon which the
emission limits for existing large, medium, and small non-rural units
are based), and these data showed percent reductions from 94.2 percent
to greater than 99 percent. To account for variability, we based the
proposed percent reduction requirement of 94 percent on the lowest
percent reduction recorded during the individual test runs (i.e., 94.2
percent). The three-run test that included the 94.2 percent value
showed significant variability and demonstrates the need to account for
variability. The percent reduction values for the three runs ranged
from 94.2 percent to 97.8 percent while there was no identifiable
change in the operation of the unit or the dry scrubber. For Pb and Cd
from existing large, medium, and small non-rural HMIWI, we used the
same methodology as for HCl, and the data sets showed even greater
variability. For Hg, we used the only available estimate of percent
reduction. The proposed percent reduction standards are 71 percent for
Pb, 74 percent for Cd, and 96 percent for Hg. The 5-year review
methodology used to assess performance of existing HMIWI resulted in no
change to the PM standards for existing large and medium units, and
CDD/CDF standards for existing small rural units. All of the other
standards for existing HMIWI were adjusted based on either the 5-year
review or the remand analyses.
Table 13 of this preamble summarizes the emission limits
promulgated in 1997, the emission limits resulting from the proposed
response to the Court remand, and the emission limits being proposed as
a result of the 5-year review for existing HMIWI. Note that these
proposed limits for existing HMIWI only apply to units for which
construction was commenced on or before June 20,
[[Page 5535]]
1996, or for which modification was commenced before March 16, 1998.
Table 13.--Summary of 1997 Promulgated Emission Limits, Proposed Remand Response Emission Limits, and Proposed 5-Year Review Limits for Existing HMIWI
--------------------------------------------------------------------------------------------------------------------------------------------------------
Proposed remand
Pollutant (units) Unit size\1\ Promulgated limit\2\ response limit\2\ Proposed 5-year review limit\2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
HCl (ppmv).......................... L, M, S................. 100 or 93% reduction.. 78 or 93% reduction... 51 or 94% reduction.
SR...................... 3,100................. 3,100................. 398
CO (ppmv)........................... All..................... 40.................... 40.................... 25
Pb (mg/dscm)........................ L, M, S................. 1.2 or 70% reduction.. 0.78 or 71% reduction. 0.64 or 71% reduction.
SR...................... 10.................... 8.9................... 0.60
Cd (mg/dscm)........................ L, M, S................. 0.16 or 65% reduction. 0.11 or 66% reduction. 0.060 or 74% reduction.
SR...................... 4..................... 4..................... 0.050
Hg (mg/dscm)........................ L, M, S................. 0.55 or 85% reduction. 0.55 or 87% reduction. 0.33 or 96% reduction.
SR...................... 7.5................... 6.6................... 0.25
PM (gr/dscf)........................ L....................... 0.015................. 0.015................. 0.015
M....................... 0.03.................. 0.030................. 0.030
S....................... 0.05.................. 0.050................. 0.030
SR...................... 0.086................. 0.086................. 0.030
CDD/CDF, total (ng/dscm)............ L, M, S................. 125................... 115................... 115
SR...................... 800................... 800................... 800
CDD/CDF, TEQ (ng/dscm).............. L, M, S................. 2.3................... 2.2................... 2.0
SR...................... 15.................... 15.................... 15
NOX (ppmv).......................... All..................... 250................... 250................... 212
SO2 (ppmv).......................... All..................... 55.................... 55.................... 28
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ L = Large; M = Medium; S = Small; SR = Small Rural
\2\ All emission limits are measured at 7 percent oxygen.
Table 14 of this preamble summarizes the emission limits
promulgated in 1997 and the emission limits being proposed as a result
of EPA's response to the Court remand for the 1997 NSPS HMIWI. Note
that these proposed limits for 1997 NSPS HMIWI only apply to units for
which construction was commenced after June 20, 1996, and on or before
the date of this proposal, or for which modification is commenced
before the date 6 months after promulgation of the proposed limits.
Also note that where the proposed 5-year review limits for existing
HMIWI are more stringent than those resulting from the remand response
for 1997 NSPS HMIWI, the more stringent limits for existing HMIWI are
included in the table as the limits being proposed. HMIWI subject to
the 1997 NSPS, however, will not find these proposed limits, as
presented in Table 14 of this preamble, in subparts Ec or Ce of 40 CFR
part 60. Instead, they must consider the proposed revisions to subpart
Ec of 40 CFR part 60 regarding existing HMIWI, as well as in the
proposed revisions to subpart Ce of 40 CFR part 60 regarding 1997 NSPS
HMIWI, and comply with the more stringent emission limit.
Table 14.--Summary of 1997 Promulgated Emission Limits and Proposed Limits in Response to the Remand for 1997
NSPS HMIWI
----------------------------------------------------------------------------------------------------------------
Promulgated
Pollutant (units) Unit size\1\ limit\2\ Proposed remand response limit\2\
----------------------------------------------------------------------------------------------------------------
HCl (ppmv)..................... L, M, S................ 15 or 99% 15 or 99% reduction.
reduction.
CO (ppmv)...................... L, M, S................ 40............... 25 \3\.
Pb (mg/dscm)................... L, M................... 0.07 or 98% 0.060 or 98% reduction.
reduction.
S...................... 1.2 or 70% 0.64 \3\ or 71% reduction.
reduction.
Cd (mg/dscm)................... L, M................... 0.04 or 90% 0.030 or 93% reduction.
reduction.
S...................... 0.16 or 65% 0.060\3\ or 74% reduction \3\.
reduction.
Hg (mg/dscm)................... L, M, S................ 0.55 or 85% 0.33\3\ or 96% reduction \3\.
reduction.
PM (gr/dscf)................... L, M................... 0.015............ 0.0090
S...................... 0.03............. 0.018
CDD/CDF, total (ng/dscm)....... L, M................... 25............... 20
S...................... 125.............. 111
CDD/CDF, TEQ (ng/dscm)......... L, M................... 0.6.............. 0.53
S...................... 2.3.............. 2.0 \3\.
NOX (ppmv)..................... L, M, S................ 250.............. 212 \3\.
SO2 (ppmv)..................... L, M, S................ 55............... 28 \3\.
----------------------------------------------------------------------------------------------------------------
\1\ L = Large; M = Medium; S = Small
\2\ All emission limits are measured at 7 percent oxygen.
\3\ Because the proposed 5-year review limit for existing HMIWI is more stringent than the one resulting from
the remand response for 1997 NSPS HMIWI, the more stringent limit for existing HMIWI is being proposed.
b. New Units. The first step in the analysis for new large and
medium HMIWI was to assess the performance of the units currently
operating a combined dry/wet control system, which is the control
technology upon
[[Page 5536]]
which the 1997 NSPS for large and medium HMIWI was based. Four units
currently are operating such controls, and we obtained compliance test
data for each unit for use in assessing performance. We selected as the
proposed emission limit the highest individual test run from the
compliance testing for each pollutant. This methodology uses actual
test data from the best-controlled sources in the industry to provide a
reasonable estimate of the performance of these units, while accounting
for variability. In several instances, the emission limit suggested by
the highest run from the four combined-control sources was higher than
either the emission limit for new sources that we are proposing in
response to the Court remand or the 5-year review emission limit that
we are proposing for existing sources. This was likely a result of the
small amount of data that we used to establish the limits, and, in
these instances, we are proposing the most stringent among these three
limits for new sources.
Although there are no small HMIWI subject to the current NSPS, we
are proposing emission limits based on the performance of moderate-
efficiency wet scrubbers, which is the control technology upon which
the 1997 limits for new small units was based. As an initial step in
selection of these emission limits, we used the performance values
representative of control with a moderate-efficiency wet scrubber as
determined for the existing medium HMIWI. We then compared these values
to the values for new small units developed in response to the remand
and, in each case, we selected the more stringent value as the proposed
emission limit.
To determine proposed percent reduction requirements for new units
for HCl, Pb, Cd, and Hg, we followed a methodology similar to that used
for existing units. For HCl, we obtained percent reduction data from
two units controlled with the MACT control technology for HCl for new
large and medium units (wet scrubbers), and these data showed percent
reductions greater than 99 percent. To account for variability, we
based the percent reduction requirement of 99 percent on the lowest
percent reduction recorded during the individual test runs (i.e., 99.1
percent). We used the same methodology for each of the three metals for
new large and medium units, and the corresponding percent reduction
standards based on the MACT control technology (dry scrubbers) are 99
percent for Pb, 99 percent for Cd, and 96 percent for Hg. For HCl from
new small HMIWI, we used the same methodology as for new large and
medium units because the MACT control technology upon which the
reductions are based is the same (wet scrubbers). For Pb and Cd from
new small HMIWI, we used the same methodology as for new large and
medium units, except that the MACT control technology upon which the
reductions are based is a wet scrubber. For Hg, we used the only
available estimate of percent reduction. The proposed percent reduction
standards for new small units are 99 percent for HCl, 71 percent for
Pb, 74 percent for Cd, and 96 percent for Hg. The 5-year review
methodology used to assess performance of new units resulted in no
change to the HCl standards for all new units. All of the other
standards for new units were adjusted based on either the 5-year review
or the remand analyses.
Table 15 of this preamble summarizes the emission limits
promulgated in 1997 and the emission limits being proposed as a result
of the 5-year review for new HMIWI. Note that these proposed limits for
new HMIWI only apply to units for which construction is commenced after
the date of this proposal, or for which modification is commenced on or
after the date 6 months after promulgation of the proposed limits.
Table 15.--Summary of 1997 Promulgated Emission Limits and Proposed 5-Year Review Limits for New HMIWI
----------------------------------------------------------------------------------------------------------------
Promulgated limit
Pollutant (units) Unit size \1\ \2\ Proposed 5-year review limit \2\
----------------------------------------------------------------------------------------------------------------
HCl (ppmv)..................... L, M, S................ 15 or 99% 15 or 99% reduction.
reduction.
CO (ppmv)...................... L, M, S................ 40............... 25
Pb (mg/dscm)................... L, M................... 0.07 or 98% 0.060 or 99% reduction.
reduction.
S...................... 1.2 or 70% 0.64 or 71% reduction.
reduction.
Cd (mg/dscm)................... L, M................... 0.04 or 90% 0.0050 or 99% reduction.
reduction.
S...................... 0.16 or 65% 0.060 or 74% reduction.
reduction.
Hg (mg/dscm)................... L, M................... 0.55 or 85% 0.19 or 96% reduction.
reduction.
S...................... 0.55 or 85% 0.33 or 96% reduction.
reduction.
PM (gr/dscf)................... L, M................... 0.015............ 0.0090
S...................... 0.03............. 0.018
CDD/CDF, total (ng/dscm)....... L, M................... 25............... 16
S...................... 125.............. 111
CDD/CDF, TEQ (ng/dscm)......... L, M................... 0.6.............. 0.21
S...................... 2.3.............. 2.0
NOX (ppmv)..................... L, M, S................ 250.............. 212
SO2 (ppmv)..................... L, M................... 55............... 21
S...................... 55............... 28
----------------------------------------------------------------------------------------------------------------
\1\ L = Large; M = Medium; S = Small.
\2\ All emission limits are measured at 7 percent oxygen.
2. How did EPA determine the proposed performance testing and
monitoring requirements?
We are proposing minor adjustments to the performance testing and
monitoring requirements that were promulgated in 1997. For existing
HMIWI and 1997 NSPS HMIWI, we are proposing retaining the current
requirements of the rule and adding the following requirements: Annual
inspections of scrubbers and fabric filters; and one-time testing of
the ash handling operations at the time of the next compliance test
using EPA Method 22 of appendix A of 40 CFR part 60. These proposed
requirements were selected to provide additional assurance that sources
continue to operate at the levels established during their initial
performance test. The proposed amendments would allow sources to use
the results of previous emissions tests to demonstrate compliance with
the
[[Page 5537]]
revised emission limits as long as the sources certify that the
previous test results are representative of current operations. Only
those sources whose previous emissions tests do not demonstrate
compliance with one or more revised emission limits would be required
to conduct another emissions test for those pollutants (note that
sources are already required to test for HCl, CO, and PM on an annual
basis).
Additional requirements also are proposed for new HMIWI. For new
sources, we are proposing retaining the current requirements and adding
the following requirements: Use of CO CEMS; annual inspections of
scrubbers and fabric filters; use of bag leak detection systems on
fabric filter-based control systems; and annual testing of the ash
handling operations using EPA Method 22 of appendix A of 40 CFR part
60. For existing sources, in addition to the proposed changes in
monitoring requirements, we also are proposing to allow for the
optional use of bag leak detection systems. We also are clarifying that
the rule allows for the following optional CEMS use: CO CEMS for
existing sources and 1997 NSPS sources; and PM CEMS, HCl CEMS, multi-
metals CEMS, Hg CEMS, and semi-continuous dioxin monitoring for
existing, 1997 NSPS, and new sources. The optional use of HCl CEMS,
multi-metals CEMS, and semi-continuous dioxin monitoring will be
available on the date a final performance specification for these
monitoring systems is published in the Federal Register or the date of
approval of a site-specific monitoring plan. The proposed testing and
monitoring provisions are discussed below.
a. Bag Leak Detection Systems. The proposed amendments would
provide, as an alternative PM monitoring technique for existing sources
and 1997 NSPS sources and a requirement for new sources, the use of bag
leak detection systems on HMIWI controlled with fabric filters. Bag
leak detection systems have been applied successfully at many
industrial sources. EPA is proposing to drop the opacity testing
requirements for HMIWI that use bag leak detection systems.
b. CO CEMS. The proposed amendments would require the use of CO
CEMS for new sources, and allow the use of CO CEMS on existing sources
and 1997 NSPS sources. Owners and operators that use CO CEMS would be
able to discontinue their annual CO compliance test as well as their
monitoring of the secondary chamber temperature. The continuous
monitoring of CO emissions is an effective way of ensuring that the
combustion unit is operating properly. The proposed amendments
incorporate the use of performance specification (PS)-4B
(Specifications and Test Procedures for Carbon Monoxide and Oxygen
Continuous Monitoring Systems in Stationary Sources) of appendix B of
40 CFR part 60.
The proposed CO emission limits are based on data from infrequent
(normally annual) stack tests and compliance would be demonstrated by
stack tests. The change to use of CO CEMS for measurement and
enforcement of the same emission limits must be carefully considered in
relation to an appropriate averaging period for data reduction. EPA
considered this issue and concluded the use of a 24-hour block average
was appropriate to address CO emissions variability, and EPA has
included the use of a 24-hour block average in the proposed rule. The
24-hour block average would be calculated following procedures in EPA
Method 19 of appendix A of 40 CFR part 60. Facilities electing to use
CO CEMS as an optional method would be required to notify EPA 1 month
before starting use of CO CEMS and 1 month before stopping use of the
CO CEMS. In addition, EPA specifically requests comment on whether
continuous monitoring of CO emissions should be required for all
existing HMIWI and all 1997 NSPS HMIWI.
c. PM CEMS. The proposed amendments would allow the use of PM CEMS
as an alternative testing and monitoring method. Owners or operators
who choose to rely on PM CEMS would be able to discontinue their annual
PM compliance test. In addition, because units that demonstrate
compliance with the PM emission limits with a PM CEMS would clearly be
meeting the opacity standard, compliance demonstration with PM CEMS
would be considered a substitute for opacity testing. Owners and
operators that use PM CEMS also would be able to discontinue their
monitoring of minimum wet scrubber pressure drop, horsepower, or
amperage. The proposed amendments incorporate the use of PS-11
(Specifications and Test Procedures for Particulate Matter Continuous
Emission Monitoring Systems at Stationary Sources) of appendix B of 40
CFR part 60 for PM CEMS, and PS-11 QA Procedure 2 to ensure that PM
CEMS are installed and operated properly and produce good quality
monitoring data.
The proposed PM emission limits are based on data from infrequent
(normally annual) stack tests and compliance would be demonstrated by
stack tests. The use of PM CEMS for measurement and enforcement of the
same emission limits must be carefully considered in relation to an
appropriate averaging period for data reduction. EPA considered this
issue and concluded the use of a 24-hour block average was appropriate
to address PM emissions variability, and EPA has included the use of a
24-hour block average in the proposed rule. The 24-hour block average
would be calculated following procedures in EPA Method 19 of appendix A
of 40 CFR part 60. An owner or operator of an HMIWI unit who wishes to
use PM CEMS would be required to notify EPA 1 month before starting use
of PM CEMS and 1 month before stopping use of the PM CEMS.
d. Other CEMS and Monitoring Systems. EPA also is proposing the
optional use of HCl CEMS, multi-metals CEMS, Hg CEMS, and semi-
continuous dioxin monitoring as alternatives to the existing methods
for demonstrating compliance with the HCl, metals (Pb, Cd, and Hg), and
CDD/CDF emissions limits. For the reasons explained above for CO CEMS
and PM CEMS, EPA has concluded that the use of 24-hour block averages
would be appropriate to address emissions variability, and EPA has
included the use of 24-hour block averages in the proposed rule. The
24-hour block averages would be calculated following procedures in EPA
Method 19 of appendix A of 40 CFR part 60. Although final performance
specifications are not yet available for HCl CEMS and multi-metals
CEMS, EPA is considering development of performance specifications. The
proposed rule specifies that these options will be available to a
facility on the date a final performance specification is published in
the Federal Register or the date of approval of a site-specific
monitoring plan.
The use of HCl CEMS would allow the discontinuation of HCl sorbent
flow rate monitoring, scrubber liquor pH monitoring, and the annual
testing requirements for HCl. EPA has proposed PS-13 (Specifications
and Test Procedures for Hydrochloric Acid Continuous Monitoring Systems
in Stationary Sources) of appendix B of 40 CFR part 60 and believes
that performance specification can serve as the basis for a performance
specification for HCl CEMS use at HMIWI. In addition to the procedures
used in proposed PS-13 for initial accuracy determination using the
relative accuracy test, a comparison against a reference method, EPA is
taking comment on an alternate initial accuracy determination
procedure, similar to the one in section 11 of PS-15 (Performance
Specification for
[[Page 5538]]
Extractive FTIR Continuous Emissions Monitor Systems in Stationary
Sources) of appendix B of 40 CFR part 60 using the dynamic or analyte
spiking procedure.
EPA believes multi-metals CEMS can be used in many applications,
including HMIWI. EPA has monitored side-by-side evaluations of multi-
metals CEMS with EPA Method 29 of appendix A of 40 CFR part 60 at
industrial waste incinerators and found good correlation. EPA also
approved the use of multi-metals CEMS as an alternative monitoring
method at a hazardous waste combustor. EPA believes it is possible to
adapt proposed PS-10 (Specifications and Test Procedures for Multi-
metals Continuous Monitoring Systems in Stationary Sources) of appendix
B of 40 CFR part 60 or other EPA performance specifications to allow
the use of multi-metals CEMS at HMIWI. In addition to the procedures
used in proposed PS-10 for initial accuracy determination using the
relative accuracy test, a comparison against a reference method, EPA is
taking comment on an alternate initial accuracy determination
procedure, similar to the one in section 11 of PS-15 using the dynamic
or analyte spiking procedure.
Relative to the use of Hg CEMS, EPA believes that PS-12A
(Specifications and Test Procedures for Total Vapor Phase Mercury
Continuous Emission Monitoring Systems in Stationary Sources) of
appendix B of 40 CFR part 60 can provide the basis for using Hg CEMS at
HMIWI. An owner or operator of an HMIWI unit who wishes to use Hg CEMS
would be required to notify EPA 1 month before starting use of Hg CEMS
and 1 month before stopping use of the Hg CEMS. The use of multi-metals
CEMS or Hg CEMS would allow the discontinuation of wet scrubber outlet
flue gas temperature monitoring. Mercury sorbent flow rate monitoring
could not be eliminated in favor of a multi-metals CEMS or Hg CEMS
because it also is an indicator of CDD/CDF control. Additionally, there
is no annual metals test that could be eliminated.
The semi-continuous monitoring of dioxin would entail use of a
continuous automated sampling system and analysis of the sample using
EPA Reference Method 23 of appendix A of 40 CFR part 60. The option to
use a continuous automated sampling system would take effect on the
date a final performance specification is published in the Federal
Register or the date of approval of a site-specific monitoring plan.
Semi-continuous monitoring of dioxin would allow the discontinuation of
fabric filter inlet temperature monitoring. Dioxin/furan sorbent flow
rate monitoring could not be eliminated in favor of semi-continuous
monitoring of dioxin because it also is an indicator of Hg control.
Additionally, there is no annual CDD/CDF test that could be eliminated.
If semi-continuous monitoring of dioxin as well as multi-metals CEMS or
Hg CEMS are used, Hg sorbent flow rate monitoring and CDD/CDF sorbent
flow rate monitoring (in both cases activated carbon is the sorbent)
could be eliminated. EPA requests comment on other parameter monitoring
requirements that could be eliminated upon use of any or all of the
optional CEMS discussed above. Table 16 of this preamble presents a
summary of the HMIWI operating parameters, the pollutants influenced by
each parameter, and alternative monitoring options for each parameter.
Table 16.--Summary of HMIWI Operating Parameters, Pollutants Influenced by Each Parameter, and Alternative
Monitoring Options for Each Parameter
----------------------------------------------------------------------------------------------------------------
Pollutants Influenced by Operating Parameter (by Control Device
Operating parameter/ Type) Alternative
monitoring requirement ------------------------------------------------------------------ monitoring
Dry scrubber Wet scrubber Combined system options
----------------------------------------------------------------------------------------------------------------
Maximum charge rate.......... All \1\............. All \1\............. All \1\............. None.
Minimum secondary chamber PM, CO, CDD/CDF..... PM, CO, CDD/CDF..... PM, CO, CDD/CDF..... CO CEMS \2\.
temperature.
Maximum fabric filter inlet CDD/CDF............. .................... CDD/CDF............. Semi-continuous
temperature. dioxin
monitoring
system
(SCDMS).
Minimum CDD/CDF sorbent flow CDD/CDF............. .................... CDD/CDF............. SCDMS and multi-
rate. metals CEMS or
Hg CEMS.
Minimum Hg sorbent flow rate. Hg.................. .................... Hg..................
Minimum HCl sorbent flow rate HCl................. .................... HCl................. HCl CEMS.
Minimum scrubber pressure .................... PM.................. PM.................. PM CEMS.
drop/ horsepower amperage.
Minimum scrubber liquor flow .................... HCl, PM, Cd, Pb, Hg, HCl, PM, Cd, Pb, Hg, HCl CEMS, PM
rate. CDD/CDF. CDD/CDF. CEMS, multi-
metals CEMS,
and SCDMS.
Minimum scrubber liquor pH... .................... HCl................. HCl................. HCl CEMS.
Maximum flue gas temperature .................... Hg.................. .................... Hg CEMS or
(wet scrubber outlet). multi-metals
CEMS.
Do not use bypass stack All \1\............. All \1\............. All \1\............. None.
(except during startup,
shutdown, and malfunction).
Air pollution control device All \1\............. All \1\............. All \1\............. None.
inspections.
----------------------------------------------------------------------------------------------------------------
\1\ ``All'' pollutants designation does not include SO2 and NOX, which are regulated at combustion-controlled
levels (no add-on controls) and have no associated parameter monitoring.
\2\ Optional method for existing and 1997 NSPS sources; required for new sources.
Table 17 of this preamble presents a summary of the HMIWI test
methods and approved alternative compliance methods.
[[Page 5539]]
Table 17.--Summary of HMIWI Test Methods and Approved Alternative Methods
----------------------------------------------------------------------------------------------------------------
Approved alternative
Pollutant/parameter Test method(s) \1\ method(s) Comments
----------------------------------------------------------------------------------------------------------------
PM................................... Method 5, Method 29.... PM CEMS................ PM CEMS are optional
for all sources in
lieu of annual PM
test.
CO................................... Method 10.............. CO CEMS................ CO CEMS are optional
for existing and 1997
NSPS sources in lieu
of annual CO test; CO
CEMS are required for
new sources.
HCl.................................. Method 26 or Method 26A HCl CEMS............... HCl CEMS are optional
for all sources in
lieu of annual HCl
test.
Cd................................... Method 29.............. Multi-metals CEMS......
Pb................................... Method 29.............. Multi-metals CEMS......
Hg................................... Method 29.............. ASTM D6784-02, multi-
metals CEMS or Hg CEMS.
CDD/CDF.............................. Method 23.............. Semi-continuous dioxin
monitoring system.
Opacity.............................. Method 22.............. Bag leak detection Bag leak detection
system or PM CEMS. systems are optional
for existing and 1997
NSPS sources; and are
required for new
sources.
Flue and exhaust gas analysis........ Method 3, 3A, or 3B.... ASME PTC 19-10-1981
Part 10.
Opacity from ash handling............ Method 22.............. None...................
----------------------------------------------------------------------------------------------------------------
\1\ EPA Reference Methods in appendix A of 40 CFR part 60.
V. Impacts of the Proposed Action for Existing Units
The emission limits for existing HMIWI that we are proposing as
part of this action are based on the actual performance of the MACT
control technologies. This proposed action is expected to result in
modest improvements in performance being required by HMIWI that are not
achieving the performance levels demonstrated in practice by the
control technologies currently being used in the industry. Based on
compliance test reports from all existing operating HMIWI (72 units at
67 facilities) following MACT compliance in September 2002, 18 existing
large HMIWI and 4 existing medium HMIWI are likely to find it necessary
to improve performance of their units in order to achieve the proposed
emission limits which their compliance test data indicates they would
not meet. The modest improvements anticipated include adding lime (for
SO2), increasing lime use (for HCl and SO2),
increasing natural gas use (for CO and CDD/CDF), and increasing
scrubber horsepower (for Pb, Cd, and Hg). Facilities may resubmit
previous compliance test data that indicates that their HMIWI meets the
proposed emission limits if the facility certifies that the test
results are representative of current operations. Those facilities
would then not be required to test for those pollutants to prove
compliance with the emission limits.
A. What are the primary air impacts?
As a result of the modest improvements estimated to be required at
22 HMIWI such that they would achieve the proposed emission limits, EPA
estimates that a total of approximately 24,700 pounds per year (lb/yr)
of the regulated pollutants would be reduced. Approximate reductions by
pollutant follow:
HCl--20,600 lb/yr
CO--400 lb/yr
Pb--35 lb/yr
Cd--3 lb/yr
Hg--30 lb/yr
PM--2,700 lb/yr
CDD/CDF--0.0007 lb/yr
NOX--200 lb/yr
SO2--700 lb/yr
B. What are the water and solid waste impacts?
EPA estimates that approximately 80 tpy of additional solid waste
and 267,000 gallons per year of additional wastewater would be
generated as a result of the increase of lime use by some facilities.
C. What are the energy impacts?
EPA estimates that approximately 3,600 megawatt-hours per year of
additional electricity would be required to support the increase in
scrubber horsepower that we estimate would be required to enable some
facilities to achieve the proposed emission limits.
D. What are the secondary air impacts?
Secondary air impacts associated with this proposed action are
direct impacts that result from the increase in natural gas use and/or
wet scrubber horsepower that we estimate may be required to enable some
facilities to achieve the proposed emission limits. We estimate that
the adjustments could result in emissions of 211 lb/yr of PM; 1,880 lb/
yr of CO; 1,230 lb/yr of NOX; and 1,450 lb/yr of
SO2 from the increased electricity and natural gas usage.
E. What are the cost and economic impacts?
EPA estimates that the national total costs for the 72 existing
HMIWI and 4 1997 NSPS HMIWI to comply with this proposed action would
be approximately $488,000 in the first year of compliance. This
estimate includes the costs that would be incurred by the 22 HMIWI that
we anticipate needing to improve performance (i.e., costs of
improvements in emissions control and emissions tests for pollutants
for which the improvements are made), and the additional monitoring
(i.e., annual control device inspections), testing (i.e. initial Method
22 test), and recordkeeping and reporting costs that would be incurred
by all 76 HMIWI as a result of this proposed action. Approximately 50
percent of the estimated total cost in the first year is for emissions
control, 11 percent is for monitoring, 32 percent is for testing, and 7
percent is for recordkeeping and reporting. National total costs for
subsequent years are estimated to be approximately $308,000 per year,
with approximately 78 percent of the total cost for emissions control,
18 percent for monitoring, and 3 percent for testing.
Economic impact analyses focus on changes in market prices and
output
[[Page 5540]]
levels. If changes in market prices and output levels in the primary
markets are significant enough, impacts on other markets are also
examined. EPA's economic impact analysis for this proposed action
assessed the magnitude of the cost of market changes resulting from the
proposed amendments by comparing annualized costs to annual sales. We
were able to assess the cost of market changes for 70 HMIWI (sales
information was unavailable for the other 6 units). For purposes of
assessing economic impacts of the proposed action, the total annualized
cost of this proposed action is estimated to be $328,000 and was
determined by first annualizing at 7 percent over 15 years the
difference between the first year costs and subsequent year costs for
each of the 76 HMIWI, and adding to that value the subsequent year
costs for each HMIWI; followed by then combining the annualized costs
for the 76 HMIWI. The $328,000 was distributed among the 76 HMIWI,
resulting in cost-to-sales ratios ranging from 0.0006 percent to 0.06
percent, with an average cost-to-sales ratio of 0.003 percent. Because
of the small size of these regulatory costs and estimated impacts, no
additional market analysis is needed. Neither the modest national costs
nor the facility level costs are anticipated to significantly impact
any market.
VI. Impacts of the Proposed Action for New Units
The current NSPS apply to HMIWI for which construction began after
June 20, 1996, or for which modification began after March 16, 1998.
There are three new HMIWI and one modified HMIWI that are subject to
the current NSPS. No additional units have become subject to the NSPS
since 2002. Considering this information, EPA does not anticipate any
new HMIWI, and, therefore, no impacts of the proposed standards for new
units. However, in the unlikely event that a new HMIWI is constructed,
we are proposing new emission limits for those units based on
performance of the control technology upon which current NSPS limits
are based, as well as additional monitoring requirements, including use
of CO CEMS and use of bag leak detection systems for fabric filters.
Because EPA does not anticipate any new HMIWI, we, therefore, do not
expect there to be any air impacts, water or solid waste impacts,
energy impacts, or cost or economic impacts associated with the
proposed standards for new sources.
VII. Relationship of the Proposed Action to Section 112(c)(6) of the
CAA
Section 112(c)(6) of the CAA requires EPA to identify categories of
sources of seven specified pollutants to assure that sources accounting
for not less than 90 percent of the aggregate emissions of each such
pollutant are subject to standards under CAA section 112(d)(2) or
112(d)(4). EPA has identified medical waste incinerators as a source
category that emits five of the seven CAA section 112(c)(6) pollutants:
Polycyclic organic matter (POM), dioxins, furans, Hg, and
polychlorinated biphenyls (PCBs). (The POM emitted by HMIWI is composed
of 16 polyaromatic hydrocarbons (PAH) and extractable organic matter
(EOM).) In the Federal Register notice Source Category Listing for
Section 112(d)(2) Rulemaking Pursuant to Section 112(c)(6)
Requirements, 63 FR 17838, 17849, Table 2 (1998), EPA identified
medical waste incinerators (now referred to as HMIWI) as a source
category ``subject to regulation'' for purposes of CAA section
112(c)(6) with respect to the CAA section 112(c)(6) pollutants that
HMIWI emit. HMIWI are solid waste incineration units currently
regulated under CAA section 129. For purposes of CAA section 112(c)(6),
EPA has determined that standards promulgated under CAA section 129 are
substantively equivalent to those promulgated under CAA section 112(d).
(See Id. at 17845; see also 62 FR 33625, 33632 (1997).) As discussed in
more detail below, the CAA section 129 standards effectively control
emissions of the five identified CAA section 112(c)(6) pollutants.
Further, since CAA section 129(h)(2) precludes EPA from regulating
these substantial sources of the five identified CAA section 112(c)(6)
pollutants under CAA section 112(d), EPA cannot further regulate these
emissions under that CAA section. As a result, EPA considers emissions
of these five pollutants from HMIWI units ``subject to standards'' for
purposes of CAA section 112(c)(6).
As required by the statute, the CAA section 129 HMIWI standards
include numeric emission limitations for the nine pollutants specified
in that section. The combination of good combustion practices and add-
on air pollution control equipment (dry sorbent injection fabric
filters, wet scrubbers, or combined fabric filter and wet scrubber
systems) effectively reduces emissions of the pollutants for which
emission limits are required under CAA section 129: Hg, CDD/CDF, Cd,
Pb, PM, SO2, HCl, CO, and NOX. Thus, the NSPS and
emissions guidelines specifically require reduction in emissions of
three of the CAA section 112(c)(6) pollutants: Dioxins, furans, and Hg.
As explained below, the air pollution controls necessary to comply with
the requirements of the HMIWI NSPS and emission guidelines also
effectively reduce emissions of the following CAA section 112(c)(6)
pollutants that are emitted from HMIWI units: POM and PCBs. Although
the CAA section 129 HMIWI standards do not have separate, specific
emissions standards for PCBs and POM, emissions of these two CAA
section 112(c)(6) pollutants are effectively controlled by the same
control measures used to comply with the numerical emissions limits for
the enumerated CAA section 129 pollutants. Specifically, as byproducts
of combustion, the formation of PCBs and POM is effectively reduced by
the combustion and post-combustion practices required to comply with
the CAA section 129 standards. Any PCBs and POM that do form during
combustion are further controlled by the various post-combustion HMIWI
controls. The add-on PM control systems (either fabric filter or wet
scrubber) and activated carbon injection in the fabric filter-based
systems further reduce emissions of these organic pollutants, as well
as reducing Hg emissions. The post-MACT compliance tests at currently
operating HMIWI show that the HMIWI MACT regulations reduced Hg
emissions by greater than 80 percent and CDD/CDF emissions by about 90
percent from pre-MACT levels. In light of the fact that similar
controls have been demonstrated to effectively reduce emissions of POM
and PCBs from another incineration source category (municipal solid
waste combustors), it is, therefore, reasonable to conclude that POM
and PCB emissions are substantially reduced at all 76 HMIWI. Thus,
while the proposed rule does not identify specific limits for POM and
PCB, they are, for the reasons noted above, nonetheless ``subject to
regulation'' for purposes of section 112(c)(6) of the CAA.
VIII. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review
Under Executive Order 12866 (58 FR 51735; October 4, 1993), this
proposed action is a ``significant regulatory action'' because it is
likely to raise novel legal or policy issues arising out of legal
mandates, the President's priorities, or the principles set forth in
the Executive Order. Accordingly, EPA submitted this proposed action to
the Office of Management and Budget (OMB) for
[[Page 5541]]
review under Executive Order 12866, and any changes made in response to
OMB recommendations have been documented in the docket for this action.
B. Paperwork Reduction Act
The information collection requirements associated with this
proposed action are included in the information collection requirements
addressing the HMIWI standards in their entirety, which have been
submitted for approval to the OMB under the Paperwork Reduction Act, 44
U.S.C. 3501 et seq. The Information Collection Request (ICR) documents
prepared by EPA have been assigned EPA ICR number 1899.04 for subpart
Ce and 1730.05 for subpart Ec.
The requirements in this proposed action result in industry
recordkeeping and reporting burden associated with review of the
amendments for all HMIWI, initial EPA Method 22 testing for all HMIWI,
annual inspections of scrubbers and fabric filters for all HMIWI, and
stack testing and development of new parameter limits for HMIWI that
need to make performance improvements. The total nationwide
recordkeeping and reporting burden of this proposed action is estimated
at 722 hours at a cost of approximately $32,800. This burden and cost
would only be applicable once. After that, the total nationwide
recordkeeping and reporting burden and costs would be $0 (above and
beyond current burden and costs).
The annual average burden associated with the emission guidelines
over the first 3 years following promulgation of this proposed action
is estimated to be 49,878 hours at a total annual labor cost of
$2,433,045. The total annualized capital/startup costs and operation
and maintenance (O&M) costs associated with the monitoring
requirements, EPA Method 22 testing, storage of data and reports, and
photocopying and postage over the 3-year period of the ICR are
estimated at $407,953 and $333,258 per year, respectively. (The annual
inspection costs are included under the recordkeeping and reporting
labor costs.) The annual average burden associated with the NSPS over
the first 3 years following promulgation of this proposed action is
estimated to be 2,004 hours at a total annual labor cost of $91,011.
The total annualized capital/startup costs are estimated at $13,046,
with total operation and maintenance costs of $36,310 per year.
Burden means the total time, effort, or financial resources
expended by persons to generate, maintain, retain, or disclose or
provide information to or for a Federal agency. This includes the time
needed to review instructions; develop, acquire, install, and utilize
technology and systems for the purposes of collecting, validating, and
verifying information, processing and maintaining information, and
disclosing and providing information; adjust the existing ways to
comply with any previously applicable instructions and requirements;
train personnel to be able to respond to a collection of information;
search data sources; complete and review the collection of information;
and transmit or otherwise disclose the information.
An Agency may not conduct or sponsor, and a person is not required
to respond to a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for EPA's
regulations are listed in 40 CFR part 9.
To comment on the Agency's need for this information, the accuracy
of the provided burden estimates, and any suggested methods for
minimizing respondent burden, including the use of automated collection
techniques, EPA has established a public docket for this action, which
includes these ICR documents, under Docket ID No. EPA-HQ-OAR-2006-0534.
Submit any comments related to the ICR documents for this proposed
action to EPA and OMB. See ADDRESSES section at the beginning of this
notice for where to submit comments to EPA. Send comments to OMB at the
Office of Information and Regulatory Affairs, Office of Management and
Budget, 725 17th Street, NW., Washington, DC 20503, Attention: Desk
Office for EPA. Since OMB is required to make a decision concerning the
ICR between 30 and 60 days after February 6, 2007, a comment to OMB is
best assured of having its full effect if OMB receives it by March 8,
2007. The final action will respond to any OMB or public comments on
the information collection requirements contained in this proposal.
C. Regulatory Flexibility Act
The Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedures Act or any other statute unless the agency certifies that
the proposed action will not have a significant economic impact on a
substantial number of small entities. Small entities include small
businesses, small government organizations, and small government
jurisdictions.
For purposes of assessing the impacts of this proposed action on
small entities, small entity is defined as follows: (1) A small
business as defined by the Small Business Administration's (SBA)
regulations at 13 CFR 121.201; (2) a small governmental jurisdiction
that is a government of a city, county, town, school district or
special district with a population of less than 50,000; or (3) a small
organization that is any not-for-profit enterprise that is
independently owned and operated and is not dominant in its field.
After considering the economic impacts of this proposed action on
small entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities. Because none
of the HMIWI facilities are expected to be significantly impacted by
this proposed action, that also means that none of the four small
entity-owned facilities would be expected to be significantly impacted.
None of the 22 HMIWI that we estimate would need to make improvements
in order to meet the proposed emission limits are owned by small
entities. The only estimated economic impacts on small entities would
result from the additional monitoring requirements (annual control
device inspections), testing requirements (one-time EPA Method 22
testing), and associated recordkeeping and reporting requirements of
this proposed action.
We continue to be interested in the potential impacts of this
proposed action on small entities and welcome comments on issues
related to such impacts.
D. Unfunded Mandates Reform Act
Title II of the Unfunded Mandates Reform Act (UMRA) of 1995, Public
Law 104-4, establishes requirements for Federal agencies to assess the
effects of their regulatory actions on State, local, and Tribal
governments and the private sector. Under section 202 of the UMRA, EPA
generally must prepare a written statement, including a cost-benefit
analysis, for proposed and final rules with ``Federal mandates'' that
may result in expenditures by State, local, and Tribal governments, in
the aggregate, or by the private sector, of $100 million or more in any
1 year. Before promulgating an EPA rule for which a written statement
is needed, section 205 of the UMRA generally requires EPA to identify
and consider a reasonable number of regulatory alternatives and adopt
the least costly, most cost-effective, or least burdensome alternative
that achieves the objectives of the proposed rule. The provisions of
section 205 do not apply when they are inconsistent with applicable
law. Moreover, section 205 allows EPA to
[[Page 5542]]
adopt an alternative other than the least costly, most cost-effective,
or least burdensome alternative if EPA publishes with the final rule an
explanation why that alternative was not adopted.
Before EPA establishes any regulatory requirements that may
significantly or uniquely affect small governments, including Tribal
governments, EPA must develop a small government agency plan under
section 203 of the UMRA. The plan must provide for notifying
potentially affected small governments, enabling officials of affected
small governments to have meaningful and timely input in the
development of EPA's regulatory proposals with significant Federal
intergovernmental mandates, and informing, educating, and advising
small governments on compliance with the regulatory requirements.
EPA has determined that this proposed action does not contain a
Federal mandate that may result in expenditures of $100 million or more
for State, local, and Tribal governments, in the aggregate, or the
private sector in any 1 year. Thus, this proposed action is not subject
to the requirements of section 202 and 205 of the UMRA. In addition,
EPA has determined that this proposed action contains no regulatory
requirements that might significantly or uniquely affect small
governments. Therefore, this proposed action is not subject to the
requirements of section 203 of the UMRA.
E. Executive Order 13132: Federalism
Executive Order 13132 (64 FR 43255; August 10, 1999), requires EPA
to develop an accountable process to ensure ``meaningful and timely
input by State and local officials in the development of regulatory
policies that have federalism implications.'' ``Policies that have
federalism implications'' are defined in the Executive Order to include
regulations that 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.'' This proposed action 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 Executive Order 13132.
This proposed action will not impose substantial direct compliance
costs on State or local governments, and will not preempt State law.
Thus, Executive Order 13132 does not apply to this proposed action.
In the spirit of Executive Order 13132, and consistent with EPA
policy to promote communications between EPA and State and local
governments, EPA specifically solicits comment on this proposed action
from State and local officials.
F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments
Executive Order 13175, (65 FR 67249; November 9, 2000), requires
EPA to develop an accountable process to ensure ``meaningful and timely
input by Tribal officials in the development of regulatory policies
that have Tribal implications.''
This proposed action does not have Tribal implications, as
specified in Executive Order 13175. It will not have substantial direct
effects on Tribal governments, on the relationship between the Federal
government and Indian tribes, or on the distribution of power and
responsibilities between the Federal government and Indian tribes, as
specified in Executive Order 13175. EPA is not aware of any HMIWI owned
or operated by Indian Tribal governments. Thus, Executive Order 13175
does not apply to this proposed action.
G. Executive Order 13045: Protection of Children From Environmental
Health and Safety Risks
Executive Order 13045 (62 FR 19885; April 23, 1997), applies to any
rule that: (1) Is determined to be ``economically significant'' as
defined under Executive Order 12866, and (2) concerns an environmental
health or safety risk that EPA has reason to believe may have a
disproportionate effect on children. If the regulatory action meets
both criteria, EPA 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 EPA considered.
EPA interprets Executive Order 13045 as applying only to those
regulatory actions that are based on health or safety risks, such that
the analysis required under section 5-501 of the Executive Order has
the potential to influence the regulation. This proposed action is not
subject to Executive Order 13045 because it is based on technology
performance and not on health and safety risks.
H. Executive Order 13211: Actions That Significantly Affect Energy
Supply, Distribution or Use
This proposed action is not a ``significant energy action'' as
defined in Executive Order 13211, ``Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use'' (66 FR
28355; May 22, 2001) because it is not likely to have a significant
adverse effect on the supply, distribution, or use of energy. EPA
estimates that the requirements in this proposed action would cause
some HMIWI to increase the horsepower of their wet scrubbers, resulting
in approximately 3,600 megawatt-hours per year of additional
electricity being used.
Given the negligible change in energy consumption resulting from
this proposed action, EPA does not expect any price increase for any
energy type. The cost of energy distribution should not be affected by
this proposed action at all since the action would not affect energy
distribution facilities. We also expect that there would be no impact
on the import of foreign energy supplies, and no other adverse outcomes
are expected to occur with regard to energy supplies.
I. National Technology Transfer Advancement Act
Section 12(d) of the National Technology Transfer and Advancement
Act (NTTAA) of 1995 (Pub. L. 104-113, Section 12(d), 15 U.S.C. 272
note) directs EPA to use voluntary consensus standards (VCS) in its
regulatory activities, unless to do so would be inconsistent with
applicable law or otherwise impractical. The VCS are technical
standards (e.g., materials specifications, test methods, sampling
procedures, and business practices) that are developed or adopted by
VCS bodies. The NTTAA directs EPA to provide Congress, through OMB,
explanations when the Agency does not use available and applicable VCS.
This proposed action involves technical standards. EPA cites the
following standards: EPA Methods 1, 3, 3A, 3B, 5, 9, 10, 10B, 22, 23,
26, 26A, and 29 in 40 CFR part 60, appendix A. Consistent with the
NTTAA, EPA conducted searches to identify voluntary consensus standards
in addition to these EPA methods. No applicable voluntary consensus
standards were identified for EPA Methods 9 and 22. The search and
review results are in the docket for this proposed action.
Two voluntary consensus standards were identified as acceptable
[[Page 5543]]
alternatives to EPA test methods for the purposes of this proposed
action. The voluntary consensus standard ASME PTC 19-10-1981-Part 10,
``Flue and Exhaust Gas Analyses,'' is cited in the proposed action for
its manual method for measuring the oxygen content of exhaust gas. This
part of ASME PTC 19-10-1981-Part 10 is an acceptable alternative to EPA
Method 3B.
The voluntary consensus standard ASTM D6784-02, ``Standard Test
Method for Elemental, Oxidized, Particle-Bound and Total Mercury Gas
Generated from Coal-Fired Stationary Sources (Ontario Hydro Method),''
is an acceptable alternative to EPA Method 29 (portion for mercury
only) as a method for measuring Hg.
The search for emissions measurement procedures identified 16 other
voluntary consensus standards. EPA determined that these 16 standards
identified for measuring emissions of the pollutants subject to
emission standards in this proposed action were impractical
alternatives to EPA test methods for the purposes of this action.
Therefore, EPA does not intend to adopt these standards for this
purpose. A document that discusses the determinations for these 16
methods is located in the docket to this proposed action.
Section 60.56c of subpart Ec of 40 CFR part 60 and Sec. 60.37e of
subpart Ce of 40 CFR part 60 list the testing methods included in the
proposed action. Under 40 CFR 60.8(b) and 60.13(i) of subpart A
(General Provisions), a source may apply to EPA for permission to use
alternative test methods or alternative monitoring requirements in
place of any required testing methods, performance specifications, or
procedures.
List of Subjects in 40 CFR Part 60
Environmental protection, Administrative practice and procedure,
Air pollution control, Intergovernmental relations, Reporting and
recordkeeping requirements.
Dated: January 26, 2007.
Stephen L. Johnson,
Administrator.
For the reasons stated in the preamble, title 40, chapter I, part
60 of the Code of Federal Regulations is proposed to be amended as
follows:
PART 60--[AMENDED]
1. The authority citation for part 60 continues to read as follows:
Authority: 42 U.S.C. 7401, et seq.
Subpart Ce--[Amended]
2. Section 60.32e is amended by revising paragraphs (a) and (i) to
read as follows:
Sec. 60.32e Designated facilities.
(a) Except as provided in paragraphs (b) through (h) of this
section, the designated facility to which the guidelines apply is each
individual HMIWI for which construction was commenced on or before June
20, 1996 and each individual HMIWI currently subject to subpart Ec as
promulgated in 1997 (for which construction was commenced after June
20, 1996 but no later than February 6, 2007 or for which modification
commenced after March 16, 1998 but no later than 6 months after the
date of promulgation of this subpart).
* * * * *
(i) Beginning 3 years after the date of promulgation of this
subpart, or on the effective date of an EPA approved operating permit
program under Clean Air Act title V and the implementing regulations
under 40 CFR part 70 in the State in which the unit is located,
whichever date is later, designated facilities subject to this subpart
shall operate pursuant to a permit issued under the EPA-approved
operating permit program.
3. Section 60.33e is amended by revising paragraph (b) to read as
follows:
Sec. 60.33e Emission guidelines.
* * * * *
(b) For approval, a State plan shall include the requirements for
emission limits at least as protective as those requirements listed in
Table 2 of this subpart for any small HMIWI constructed on or before
June 20, 1996 which is located more than 50 miles from the boundary of
the nearest Standard Metropolitan Statistical Area (defined in Sec.
60.31e) and which burns less than 2,000 pounds per week of hospital
waste and medical/infectious waste. The 2,000 lb/week limitation does
not apply during performance tests.
* * * * *
4. Section 60.36e is amended by adding paragraphs (c) and (d) to
read as follows:
Sec. 60.36e Inspection guidelines.
* * * * *
(c) For approval, a State plan shall require that each HMIWI
subject to the emission limits under Sec. 60.33e(a) undergo an initial
air pollution control device inspection that is at least as protective
as the following within 1 year following approval of the State plan:
(1) At a minimum, an inspection shall include the following:
(i) Inspect air pollution control device(s) for proper operation,
if applicable;
(ii) Ensure proper calibration of thermocouples, sorbent feed
systems, and any other monitoring equipment; and
(iii) Generally observe that the equipment is maintained in good
operating condition.
(2) Within 10 operating days following an air pollution control
device inspection, all necessary repairs shall be completed unless the
owner or operator obtains written approval from the State agency
establishing a date whereby all necessary repairs of the designated
facility shall be completed.
(d) For approval, a State plan shall require that each HMIWI
subject to the emission limits under Sec. 60.33e(a) undergo an air
pollution control device inspection annually (no more than 12 months
following the previous annual air pollution control device inspection),
as outlined in paragraphs (c)(1) and (2) of this section.
5. Section 60.37e is amended by revising paragraphs (a) and (b)(1)
and adding paragraph (e) to read as follows:
Sec. 60.37e Compliance, performance testing, and monitoring
guidelines.
(a) Except as provided in paragraph (b) of this section, for
approval, a State plan shall include the requirements for compliance
and performance testing listed in Sec. 60.56c of subpart Ec of this
part, excluding the fugitive emissions annual testing requirement under
Sec. 60.56c(c)(3), the CO CEMS requirements under Sec. 60.56c(c)(5),
and the bag leak detection system requirements under Sec. 60.57c(g).
Sources may, however, elect to use CO CEMS as specified under Sec.
60.56c(c)(5) or bag leak detection systems as specified under Sec.
60.57c(g).
(b) * * *
(1) Conduct the performance testing requirements in Sec.
60.56c(a), (b)(1) through (b)(9), (b)(11) (Hg only), (b)(12), and
(c)(1) of subpart Ec of this part. The 2,000 lb/week limitation under
Sec. 60.33e(b) does not apply during performance tests.
* * * * *
(e) The owner or operator of a designated facility may use the
results of previous emissions tests to demonstrate compliance with the
emission limits, provided that the conditions in paragraphs (e)(1)
through (e)(3) of this section are met:
(1) The previous emissions tests must have been conducted using the
applicable procedures and test methods
[[Page 5544]]
listed in Sec. 60.56c(b)(1) through (b)(9), (b)(11) (Hg only), and
(b)(12). Previous emissions test results obtained using EPA-accepted
voluntary consensus standards are also acceptable.
(2) The HMIWI at the affected facility shall be operated in a
manner (e.g., with charge rate, secondary chamber temperature, etc.)
that would be expected to result in the same or lower emissions than
observed during the previous emissions test(s), and the HMIWI may not
have been modified such that emissions would be expected to exceed
(notwithstanding normal test-to-test variability) the results from
previous emissions test(s).
(3) The previous emissions test(s) must have been conducted in 1997
or later.
6. Section 60.38e is amended by revising paragraph (a) and adding
paragraph (c) to read as follows:
Sec. 60.38e Reporting and recordkeeping guidelines.
(a) For approval, a State plan shall include the reporting and
recordkeeping requirements listed in Sec. 60.58c(b), (c), (d), (e),
and (f) of subpart Ec of this part, excluding Sec. 60.58c(b)(7)
(siting).
* * * * *
(c) For approval, a State plan shall require the owner or operator
of each HMIWI subject to the emission limits under Sec. 60.33e(a) to:
(1) Maintain records of the annual air pollution control device
inspections, any required maintenance, and any repairs not completed
within 10 days of an inspection or the timeframe established by the
State regulatory agency; and
(2) Submit an annual report containing information recorded under
paragraph (c)(1) of this section no later than 60 days following the
year in which data were collected. Subsequent reports shall be sent no
later than 12 calendar months following the previous report (once the
unit is subject to permitting requirements under title V of the Act,
the owner or operator shall submit these reports semiannually). The
report shall be signed by the facilities manager.
7. Section 60.39e is amended as follows:
a. By revising paragraph (a);
b. By revising paragraph (c) introductory text;
c. By revising paragraph (d)(3); and
d. By revising paragraph (f).
Sec. 60.39e Compliance times.
(a) Not later than 1 year after the date of promulgation of this
subpart, each State in which a designated facility is operating shall
submit to the Administrator a plan to implement and enforce the
emission guidelines.
* * * * *
(c) State plans that specify measurable and enforceable incremental
steps of progress towards compliance for designated facilities planning
to install the necessary air pollution control equipment may allow
compliance on or before the date 3 years after EPA approval of the
State plan (but not later than 5 years after the date of promulgation
of this subpart). Suggested measurable and enforceable activities to be
included in State plans are:
* * * * *
(d) * * *
(3) If an extension is granted, require compliance with the
emission guidelines on or before the date 3 years after EPA approval of
the State plan (but not later than 5 years after the date of
promulgation of this subpart).
* * * * *
(f) The Administrator shall develop, implement, and enforce a plan
for existing HMIWI located in any State that has not submitted an
approvable plan within 2 years after the date of promulgation of this
subpart. Such plans shall ensure that each designated facility is in
compliance with the provisions of this subpart no later than 5 years
after the date of promulgation of this subpart.
8. Table 1 to subpart Ce is revised to read as follows:
Table 1 to Subpart Ce.--Emission Limits for Small, Medium, and Large HMIWI
----------------------------------------------------------------------------------------------------------------
Emission limits HMIWI size
Pollutant Units (7 percent --------------------------------------------------------
oxygen, dry basis) Small Medium Large
----------------------------------------------------------------------------------------------------------------
Particulate matter............. Milligrams per dry 69 (0.030)....... 69 (0.030)....... 34 (0.015).
standard cubic meter
(mg/dscm) (grains per
dry standard cubic
foot (gr/dscf)).
Carbon monoxide................ Parts per million by 25............... 25............... 25.
volume (ppmv).
Dioxins/furans................. Nanograms per dry 115 (50) or 2.0 115 (50) or 2.0 115 (50) or 2.0
standard cubic meter (0.87). (0.87). (0.87).
total dioxins/furans
(ng/dscm) (grains per
billion dry standard
cubic feet (gr/10\9\
dscf)) or ng/dscm TEQ
(gr/10\9\ dscf).
Hydrogen chloride.............. ppmv or percent 51 or 94%........ 51 or 94%........ 51 or 94%
reduction.
Sulfur dioxide................. Ppmv.................. 28............... 28............... 28.
Nitrogen oxides................ Ppmv.................. 212.............. 212.............. 212.
Lead........................... mg/dscm (grains per 0.64 (0.28) or 0.64 (0.28) or 0.64 (0.28) or
thousand dry standard 71%. 71%. 71%.
cubic feet (gr/10\3\
dscf)) or percent
reduction.
Cadmium........................ mg/dscm (gr/10\3\ 0.060 (0.026) or 0.060 (0.026) or 0.060 (0.026) or
dscf) or percent 74%. 74%. 74%.
reduction.
Mercury........................ mg/dscm (gr/10\3\ 0.33 (0.14) or 0.33 (0.14) or 0.33 (0.14) or
dscf) or percent 96%. 96%. 96%.
reduction.
----------------------------------------------------------------------------------------------------------------
9. Table 2 of subpart Ce is revised to read as follows:
Table 2 to Subpart Ce.--Emission Limits for Small HMIWI Which Meet the Criteria Under Sec. 60.33E(B)
----------------------------------------------------------------------------------------------------------------
Units (7 percent oxygen, dry
Pollutant basis) HMIWI emission limits
----------------------------------------------------------------------------------------------------------------
Particulate matter.................... mg/dscm (gr/dscf)............. 69 (0.030).
Carbon monoxide....................... Ppmv.......................... 25.
[[Page 5545]]
Dioxins/furans........................ ng/dscm total dioxins/furans 800 (350) or 15 (6.6).
(gr/10\9\ dscf) or ng/dscm
TEQ (gr/10\9\ dscf).
Hydrogen chloride..................... ppmv or percent reduction..... 398.
Sulfur dioxide........................ Ppmv.......................... 28.
Nitrogen oxides....................... Ppmv.......................... 212.
Lead.................................. mg/dscm (gr/10\3\ dscf) or 0.60 (0.26).
percent reduction.
Cadmium............................... mg/dscm (gr/10\3\ dscf) or 0.050 (0.022).
percent reduction.
Mercury............................... mg/dscm (gr/10\3\ dscf) or 0.25 (0.11).
percent reduction.
----------------------------------------------------------------------------------------------------------------
Subpart Ec--[Amended]
10. Section 60.50c is amended by revising paragraphs (a), (k) and
(l) to read as follows:
Sec. 60.50c Applicability and delegation of authority.
(a) Except as provided in paragraphs (b) through (h) of this
section, the affected facility to which this subpart applies is each
individual hospital/medical/infectious waste incinerator (HMIWI):
(1) For which construction is commenced after June 20, 1996 but no
later than February 6, 2007;
(2) For which modification is commenced after March 16, 1998 but no
later than 6 months after the date of promulgation of this subpart;
(3) For which construction is commenced after February 6, 2007; or
(4) For which modification is commenced after 6 months after the
date of promulgation of this subpart.
* * * * *
(k) The requirements of this subpart shall become effective 6
months after the date of promulgation of this subpart.
(l) Beginning 3 years after the date of promulgation of this
subpart, or on the effective date of an EPA-approved operating permit
program under Clean Air Act title V and the implementing regulations
under 40 CFR part 70 in the State in which the unit is located,
whichever date is later, affected facilities subject to this subpart
shall operate pursuant to a permit issued under the EPA approved State
operating permit program.
11. Section 60.51c is amended by adding a definition for ``Bag leak
detection system'' in alphabetical order and revising the definition
for ``Minimum secondary chamber temperature'' to read as follows:
Sec. 60.51c Definitions.
Bag leak detection system means an instrument that is capable of
monitoring PM loadings in the exhaust of a fabric filter in order to
detect bag failures. A bag leak detection system includes, but is not
limited to, an instrument that operates on triboelectric, light-
scattering, light-transmittance, or other effects to monitor relative
PM loadings.
* * * * *
Minimum secondary chamber temperature means 90 percent of the
highest 3-hour average secondary chamber temperature (taken, at a
minimum, once every minute) measured during the most recent performance
test demonstrating compliance with the PM, CO, and dioxin/furan
emission limits.
* * * * *
12. Section 60.52c is amended by revising paragraph (c) to read as
follows:
Sec. 60.52c Emission limits.
* * * * *
(c) On and after the date on which the initial performance test is
completed or is required to be completed under Sec. 60.8, whichever
date comes first, no owner or operator of an affected facility shall
cause to be discharged into the atmosphere visible emissions of
combustion ash from an ash conveying system (including conveyor
transfer points) in excess of 5 percent of the observation period
(i.e., 9 minutes per 3-hour period), as determined by EPA Reference
Method 22 of appendix A of this part, except as provided in paragraphs
(d) and (e) of this section.
* * * * *
13. Section 60.56c is amended as follows:
a. By revising paragraph (b) introductory text;
b. By revising paragraphs (b)(4) and (b)(6) through (b)(8), (b)(9)
introductory text, and (b)(10);
c. By revising paragraph (b)(11);
d. By revising paragraphs (c)(2) through (4);
e. By adding paragraphs (c)(5), and (c)(6);
f. By revising paragraph (d) introductory text;
g. By adding paragraphs (e)(6) and (7);
h. By adding paragraphs (f)(7) through (9);
i. By adding paragraphs (g)(6) through (9); and
j. By adding paragraph (k).
Sec. 60.56c Compliance and performance testing.
* * * * *
(b) Except as provided in paragraph (k) of this section, the owner
or operator of an affected facility shall conduct an initial
performance test as required under Sec. 60.8 to determine compliance
with the emission limits using the procedures and test methods listed
in paragraphs (b)(1) through (b)(12) of this section. The use of the
bypass stack during a performance test shall invalidate the performance
test.
* * * * *
(4) EPA Reference Method 3, 3A, or 3B of appendix A of this part
shall be used for gas composition analysis, including measurement of
oxygen concentration. EPA Reference Method 3, 3A, or 3B of appendix A
of this part shall be used simultaneously with each of the other EPA
reference methods. As an alternative, ASME PTC-19-10-1981-Part 10 may
be used.
* * * * *
(6) EPA Reference Method 5 or 29 of appendix A of this part shall
be used to measure the particulate matter emissions. As an alternative,
PM CEMS may be used as specified in paragraph (c)(4) of this section.
(7) EPA Reference Method 9 of appendix A of this part shall be used
to measure stack opacity. As an alternative, demonstration of
compliance with the PM standards using bag leak detection systems as
specified in Sec. 60.57c(g) or PM CEMS as specified in paragraph
(c)(4) of this section is considered demonstrative of compliance with
the opacity requirements.
(8) For affected facilities under Sec. 60.50c(a)(1) and (a)(2),
EPA Reference Method 10 or 10B of appendix A of this part shall be used
to measure the CO emissions. As an alternative, CO CEMS may be used as
specified in paragraph (c)(4) of this section.
(9) EPA Reference Method 23 of appendix A of this part shall be
used to
[[Page 5546]]
measure total dioxin/furan emissions. As an alternative, an owner or
operator may elect to sample dioxins/furans by installing, calibrating,
maintaining, and operating a continuous automated sampling system for
monitoring dioxin/furan emissions as specified in paragraph (c)(6) of
this section. For Method 23 sampling, the minimum sample time shall be
4 hours per test run. If the affected facility has selected the toxic
equivalency standards for dioxins/furans, under Sec. 60.52c, the
following procedures shall be used to determine compliance:
* * * * *
(10) EPA Reference Method 26 or 26A of appendix A of this part
shall be used to measure HCl emissions, with the additional
requirements for Method 26A specified in paragraphs (b)(10)(i) through
(iii) of this section. As an alternative, HCl CEMS may be used as
specified in paragraph (c)(4) of this section. If the affected facility
has selected the percentage reduction standards for HCl under Sec.
60.52c, the percentage reduction in HCl emission (%RHCl) is
computed using the following formula:
(%RHCl) = (Ei-Eo)/Ei x 100
Where:
%RHCl=percentage reduction of HCl emissions achieved;
Ei=HCl emission concentration measured at the control
device inlet, corrected to 7 percent oxygen (dry basis); and
Eo=HCl emission concentration measured at the control
device outlet, corrected to 7 percent oxygen (dry basis).
(i) The probe and filter shall be conditioned prior to sampling
using the procedure described in paragraphs (b)(10)(i)(A) through (C)
of this section.
(A) Assemble the sampling train(s) and conduct a conditioning run
by collecting between 14 liters per minute (L/min)--(0.5 cubic feet per
minute (ft \3\/min)) and 30 L/min (1.0 ft \3\/min) of gas over a 1-hour
period. Follow the sampling procedures outlined in section 8.1.5 of
Method 26A of appendix A of this part. For the conditioning run, water
may be used as the impinger solution.
(B) Remove the impingers from the sampling train and replace with a
fresh impinger train for the sampling run, leaving the probe and filter
(and cyclone, if used) in position. Do not recover the filter or rinse
the probe before the first run. Thoroughly rinse the impingers used in
the preconditioning run with deionized water and discard these rinses.
(C) The probe and filter assembly shall be conditioned by the stack
gas and shall not be recovered or cleaned until the end of testing.
(ii) For the duration of sampling, a temperature around the probe
and filter (and cyclone, if used) between 120 [deg]C (248 [deg]F) and
134 [deg]C (273 [deg]F) shall be maintained.
(iii) If water droplets are present in the sample gas stream, the
requirements specified in paragraphs (b)(10)(iii)(A) and (B) of this
section shall be met.
(A) The cyclone described in section 6.1.4 of EPA Reference Method
26A of appendix A of this part shall be used.
(B) The post-test moisture removal procedure described in section
8.1.6 of EPA Reference Method 26A of appendix A of this part shall be
used.
(11) EPA Reference Method 29 of appendix A of this part shall be
used to measure Pb, Cd, and Hg emissions. As an alternative, Hg
emissions may be measured using ASTM D6784-02. As an alternative for
Pb, Cd, and Hg, multi-metals CEMS, or Hg CEMS, may be used as specified
in paragraph (c)(4) of this section. If the affected facility has
selected the percentage reduction standards for metals under Sec.
60.52c, the percentage reduction in emissions (%Rmetal) is
computed using the following formula:
(%Rmetal) = (Ei-Eo)/Ei x
100
Where:
%Rmetal=percentage reduction of metal emission (Pb, Cd,
or Hg) achieved;
Ei=metal emission concentration (Pb, Cd, or Hg) measured
at the control device inlet, corrected to 7 percent oxygen (dry
basis); and
Eo=metal emission concentration (Pb, Cd, or Hg) measured
at the control device outlet, corrected to 7 percent oxygen (dry
basis).
* * * * *
(c) * * *
(2) Except as provided in paragraphs (c)(4) and (c)(5) of this
section, determine compliance with the PM, CO, and HCl emission limits
by conducting an annual performance test (no more than 12 months
following the previous performance test) using the applicable
procedures and test methods listed in paragraph (b) of this section. If
all three performance tests over a 3-year period indicate compliance
with the emission limit for a pollutant (PM, CO, or HCl), the owner or
operator may forego a performance test for that pollutant for the
subsequent 2 years. At a minimum, a performance test for PM, CO, and
HCl shall be conducted every third year (no more than 36 months
following the previous performance test). If a performance test
conducted every third year indicates compliance with the emission limit
for a pollutant (PM, CO, or HCl), the owner or operator may forego a
performance test for that pollutant for an additional 2 years. If any
performance test indicates noncompliance with the respective emission
limit, a performance test for that pollutant shall be conducted
annually until all annual performance tests over a 3-year period
indicate compliance with the emission limit. The use of the bypass
stack during a performance test shall invalidate the performance test.
(3) For large HMIWI under Sec. 60.50c(a)(1) and (a)(2) and for all
HMIWI under Sec. 60.50c(a)(3) and (a)(4), determine compliance with
the visible emission limits for fugitive emissions from flyash/bottom
ash storage and handling by conducting a performance test using EPA
Reference Method 22 on an annual basis (no more than 12 months
following the previous performance test).
(4) Facilities using optional CEMS to demonstrate compliance with
the PM, CO, HCl, Pb, Cd, and/or Hg emission limits under Sec. 60.52c
shall:
(i) Determine compliance with the appropriate emission limit(s)
using a 24-hour block average, calculated as specified in section
12.4.1 of EPA Reference Method 19 of appendix A of this part.
(ii) Operate all CEMS in accordance with the applicable procedures
under appendices B and F of this part. For those CEMS for which
performance specifications have not yet been promulgated (HCl, multi-
metals), this option takes effect on the date a final performance
specification is published in the Federal Register or the date of
approval of a site-specific monitoring plan.
(iii) Be allowed to substitute use of an HCl CEMS for the HCl
annual performance test, minimum HCl sorbent flow rate, and minimum
scrubber liquor pH to demonstrate compliance with the HCl emission
limit.
(iv) Be allowed to substitute use of a PM CEMS for the PM annual
performance test and minimum pressure drop across the wet scrubber, if
applicable, to demonstrate compliance with the PM emission limit.
(v) Be allowed to substitute use of a CO CEMS for the CO annual
performance test and minimum secondary chamber temperature to
demonstrate compliance with the CO emission limit.
(5) For affected facilities under Sec. 60.50c(a)(3) and (a)(4),
determine compliance with the CO emission limit using a CO CEMS
according to paragraphs (c)(5)(i) and (c)(5)(ii) of this section:
[[Page 5547]]
(i) Determine compliance with the CO emission limit using a 24-hour
block average, calculated as specified in section 12.4.1 of EPA
Reference Method 19 of appendix A of this part.
(ii) Operate the CO CEMS in accordance with the applicable
procedures under appendices B and F of this part.
(iii) Use of a CO CEMS may be substituted for the CO annual
performance test and minimum secondary chamber temperature to
demonstrate compliance with the CO emission limit.
(6) Facilities using a continuous automated sampling system to
demonstrate compliance with the dioxin/furan emission limits under
Sec. 60.52c shall record the output of the system and analyze the
sample using EPA Reference Method 23 of appendix A of this part. This
option to use a continuous automated sampling system takes effect on
the date a final performance specification applicable to dioxin/furan
from monitors is published in the Federal Register or the date of
approval of a site-specific monitoring plan. The owner or operator of
an affected facility who elects to continuously sample dioxin/furan
emissions instead of sampling and testing using EPA Reference Method 23
shall install, calibrate, maintain, and operate a continuous automated
sampling system and shall comply with the requirements specified in
Sec. 60.58b(p) and (q) of subpart Eb of this part.
(d) Except as provided in paragraphs (c)(4), (c)(5), and (c)(6) of
this section, the owner or operator of an affected facility equipped
with a dry scrubber followed by a fabric filter, a wet scrubber, or a
dry scrubber followed by a fabric filter and wet scrubber shall:
* * * * *
(e) * * *
(6) For HMIWI under Sec. 60.50c(a)(3) and (a)(4), operation of the
affected facility above the CO emission limit as measured by the CO
CEMS shall constitute a violation of the CO emission limit.
(7) For HMIWI under Sec. 60.50c(a)(3) and (a)(4), failure to
initiate corrective action within 1 hour of a bag leak detection system
alarm; or failure to operate and maintain the fabric filter such that
the alarm is not engaged for more than 5 percent of the total operating
time in a 6-month block reporting period shall constitute a violation
of the PM emission limit. If inspection of the fabric filter
demonstrates that no corrective action is required, no alarm time is
counted. If corrective action is required, each alarm is counted as a
minimum of 1 hour. If it takes longer than 1 hour to initiate
corrective action, the alarm time is counted as the actual amount of
time taken to initiate corrective action. If the bag leak detection
system is used to demonstrate compliance with the opacity limit, this
would also constitute a violation of the opacity emission limit.
(f) * * *
(7) For HMIWI under Sec. 60.50c(a)(3) and (a)(4), operation of the
affected facility above the CO emission limit as measured by the CO
CEMS shall constitute a violation of the CO emission limit.
(8) For all HMIWI, operation of the affected facility above the PM,
CO, HCl, Pb, Cd, and/or Hg emission limit as measured by the CEMS
specified in paragraph (c)(4) of this section shall constitute a
violation of the applicable emission limit.
(9) For all HMIWI, operation of the affected facility above the
CDD/CDF emission limit as measured by the continuous automated sampling
system specified in paragraph (c)(6) of this section shall constitute a
violation of the CDD/CDF emission limit.
(g) * * *
(6) For HMIWI under Sec. 60.50c(a)(3) and (a)(4), operation of the
affected facility above the CO emission limit as measured by the CO
CEMS shall constitute a violation of the CO emission limit.
(7) For HMIWI under Sec. 60.50c(a)(3) and (a)(4), failure to
initiate corrective action within 1 hour of a bag leak detection system
alarm; or failure to operate and maintain the fabric filter such that
the alarm is not engaged for more than 5 percent of the total operating
time in a 6-month block reporting period shall constitute a violation
of the PM emission limit. If inspection of the fabric filter
demonstrates that no corrective action is required, no alarm time is
counted. If corrective action is required, each alarm is counted as a
minimum of 1 hour. If it takes longer than 1 hour to initiate
corrective action, the alarm time is counted as the actual amount of
time taken to initiate corrective action. If the bag leak detection
system is used to demonstrate compliance with the opacity limit, this
would also constitute a violation of the opacity emission limit.
(8) For all HMIWI, operation of the affected facility above the PM,
CO, HCl, Pb, Cd, and/or Hg emission limit as measured by the CEMS
specified in paragraph (c)(4) of this section shall constitute a
violation of the applicable emission limit.
(9) For all HMIWI, operation of the affected facility above the
CDD/CDF emission limit as measured by the continuous automated sampling
system specified in paragraph (c)(6) of this section shall constitute a
violation of the CDD/CDF emission limit.
* * * * *
(k) The owner or operator of an affected facility may use the
results of previous emissions tests to demonstrate compliance with the
emission limits, provided that the conditions in paragraphs (k)(1)
through (k)(3) of this section are met:
(1) The previous emissions tests shall have been conducted using
the applicable procedures and test methods listed in paragraph (b) of
this section. Previous emissions test results obtained using EPA-
accepted voluntary consensus standards are also acceptable.
(2) The HMIWI at the affected facility shall be operated in a
manner (e.g., with charge rate, secondary chamber temperature, etc.)
that would be expected to result in the same or lower emissions than
observed during the previous emissions test(s) and the HMIWI may not
have been modified such that emissions would be expected to exceed
(notwithstanding normal test-to-test variability) the results from
previous emissions test(s).
(3) The previous emissions test(s) shall have been conducted in
1997 or later.
14. Section 60.57c is amended as follows:
a. By revising paragraph (a);
b. By adding paragraph (e);
c. By adding paragraph (f); and
d. By adding paragraph (g).
Sec. 60.57c Monitoring requirements
(a) Except as provided in Sec. 60.56c(c)(4) through (c)(6), the
owner or operator of an affected facility shall install, calibrate (to
manufacturers' specifications), maintain, and operate devices (or
establish methods) for monitoring the applicable maximum and minimum
operating parameters listed in Table 3 to this subpart (unless optional
CEMS are used as a substitute for certain parameters as specified) such
that these devices (or methods) measure and record values for these
operating parameters at the frequencies indicated in Table 3 at all
times except during periods of startup and shutdown.
* * * * *
(e) The owner or operator of an affected facility shall ensure that
each HMIWI subject to the emission limits in Sec. 60.52c undergoes an
initial air pollution control device inspection that is at least as
protective as the following:
[[Page 5548]]
(1) At a minimum, an inspection shall include the following:
(i) Inspect air pollution control device(s) for proper operation,
if applicable;
(ii) Ensure proper calibration of thermocouples, sorbent feed
systems, and any other monitoring equipment; and
(iii) Generally observe that the equipment is maintained in good
operating condition.
(2) Within 10 operating days following an air pollution control
device inspection, all necessary repairs shall be completed unless the
owner or operator obtains written approval from the Administrator
establishing a date whereby all necessary repairs of the designated
facility shall be completed.
(f) The owner or operator of an affected facility shall ensure that
each HMIWI subject to the emission limits under Sec. 60.52c undergoes
an air pollution control device inspection annually (no more than 12
months following the previous annual air pollution control device
inspection), as outlined in paragraphs (e)(1) and (e)(2) of this
section.
(g) For affected facilities under Sec. 60.50c(a)(3) and (a)(4)
using an air pollution control device that includes a fabric filter and
not using PM CEMS, determine compliance with the PM emission limit
using a bag leak detection system and meet the requirements in
paragraphs (g)(1) through (g)(12) of this section for each bag leak
detection system. Affected facilities under Sec. 60.50c(a)(1) and
(a)(2) may elect to demonstrate continuous compliance with the PM
emission limit using a bag leak detection system and meet the
requirements in paragraphs (g)(1) through (g)(12) of this section.
(1) Each triboelectric bag leak detection system shall be
installed, calibrated, operated, and maintained according to the
``Fabric Filter Bag Leak Detection Guidance,'' (EPA 454/R-98-015,
September 1997). This document is available from the U.S. Environmental
Protection Agency (U.S. EPA); Office of Air Quality Planning and
Standards; Sector Policies and Programs Division; Measurement Policy
Group (D-243-02), Research Triangle Park, NC 27711. This document is
also available on the Technology Transfer Network (TTN) under Emission
Measurement Center Continuous Emission Monitoring. Other types of bag
leak detection systems shall be installed, operated, calibrated, and
maintained in a manner consistent with the manufacturer's written
specifications and recommendations.
(2) The bag leak detection system shall be certified by the
manufacturer to be capable of detecting PM emissions at concentrations
of 10 milligrams per actual cubic meter (0.0044 grains per actual cubic
foot) or less.
(3) The bag leak detection system sensor shall provide an output of
relative PM loadings.
(4) The bag leak detection system shall be equipped with a device
to continuously record the output signal from the sensor.
(5) The bag leak detection system shall be equipped with an audible
alarm system that will sound automatically when an increase in relative
PM emissions over a preset level is detected. The alarm shall be
located where it is easily heard by plant operating personnel.
(6) For positive pressure fabric filter systems, a bag leak
detector shall be installed in each baghouse compartment or cell.
(7) For negative pressure or induced air fabric filters, the bag
leak detector shall be installed downstream of the fabric filter.
(8) Where multiple detectors are required, the system's
instrumentation and alarm may be shared among detectors.
(9) The baseline output shall be established by adjusting the range
and the averaging period of the device and establishing the alarm set
points and the alarm delay time according to section 5.0 of the
``Fabric Filter Bag Leak Detection Guidance.''
(10) Following initial adjustment of the system, the sensitivity or
range, averaging period, alarm set points, or alarm delay time may not
be adjusted. In no case may the sensitivity be increased by more than
100 percent or decreased more than 50 percent over a 365-day period
unless such adjustment follows a complete fabric filter inspection that
demonstrates that the fabric filter is in good operating condition.
Each adjustment shall be recorded.
(11) Record the results of each inspection, calibration, and
validation check.
(12) Initiate corrective action within 1 hour of a bag leak
detection system alarm; operate and maintain the fabric filter such
that the alarm is not engaged for more than 5 percent of the total
operating time in a 6-month block reporting period. If inspection of
the fabric filter demonstrates that no corrective action is required,
no alarm time is counted. If corrective action is required, each alarm
is counted as a minimum of 1 hour. If it takes longer than 1 hour to
initiate corrective action, the alarm time is counted as the actual
amount of time taken to initiate corrective action.
15. Section 60.58c is amended as follows:
a. By adding paragraphs (b)(2)(xvi) through (xviii);
b. By revising paragraph (b)(6);
c. By revising paragraph (c) introductory text;
d. By revising paragraph (c)(2);
e. By adding paragraph (c)(4);
f. By revising paragraph (d) introductory text;
g. By adding paragraphs (d)(9) through (11); and
h. By adding paragraph (g).
Sec. 60.58c Reporting and recordkeeping requirements.
* * * * *
(b) * * *
(2) * * *
(xvi) Records of the annual air pollution control device
inspections, any required maintenance, and any repairs not completed
within 10 days of an inspection or the timeframe established by the
Administrator.
(xvii) For affected facilities using a bag leak detection system,
records of each alarm, the time of the alarm, the time corrective
action was initiated and completed, and a brief description of the
cause of the alarm and the corrective action taken.
(xviii) For affected facilities under Sec. 60.50c(a)(3) and
(a)(4), concentrations of CO as determined by the continuous emission
monitoring system.
* * * * *
(6) The results of the initial, annual, and any subsequent
performance tests conducted to determine compliance with the emission
limits and/or to establish or re-establish operating parameters, as
applicable, and a description of how the operating parameters were
established or re-established, if applicable.
* * * * *
(c) The owner or operator of an affected facility shall submit the
information specified in paragraphs (c)(1) through (c)(4) of this
section no later than 60 days following the initial performance test.
All reports shall be signed by the facilities manager.
* * * * *
(2) The values for the site-specific operating parameters
established pursuant to Sec. 60.56c(d) or Sec. 60.56c(i), as
applicable, and a description of how the operating parameters were
established during the initial performance test.
* * * * *
(4) For each affected facility that uses a bag leak detection
system, analysis and supporting documentation
[[Page 5549]]
demonstrating conformance with EPA guidance and specifications for bag
leak detection systems in Sec. 60.57c(g).
(d) An annual report shall be submitted 1 year following the
submission of the information in paragraph (c) of this section and
subsequent reports shall be submitted no more than 12 months following
the previous report (once the unit is subject to permitting
requirements under title V of the Clean Air Act, the owner or operator
of an affected facility must submit these reports semiannually). The
annual report shall include the information specified in paragraphs
(d)(1) through (9) of this section. All reports shall be signed by the
facilities manager.
* * * * *
(9) Records of the annual air pollution control device inspection,
any required maintenance, and any repairs not completed within 10 days
of an inspection or the timeframe established by the Administrator.
(10) For affected facilities using a bag leak detection system,
records of each alarm, the time of the alarm, the time corrective
action was initiated and completed, and a brief description of the
cause of the alarm and the corrective action taken.
(11) For affected facilities under Sec. 60.50c(a)(3) and (a)(4),
concentrations of CO as determined by the continuous emission
monitoring system.
* * * * *
(g) The owner or operator of an affected facility that uses the
results of previous emissions tests to demonstrate compliance with the
emission limits shall submit the information specified in paragraphs
(g)(1) through (g)(4) of this section no later than [DATE 30 DAYS AFTER
DATE OF PUBLICATION OF FINAL RULE]. All reports shall have been signed
by the facility's manager.
(1) The previous emissions test results as recorded using the
methods and procedures in Sec. 60.56c(b)(1) through (12), as
applicable. Previous emissions test results recorded using EPA-accepted
voluntary consensus standards are also acceptable.
(2) Certification that the test results are representative of
current operations.
(3) The values for the site-specific operating parameters
established pursuant to Sec. 60.56c(d) or (i), as applicable.
(4) The waste management plan as specified in Sec. 60.55c.
16. Table 1 to subpart Ec is revised to read as follows:
Table 1 to Subpart Ec of Part 60.--Emission Limits for Small, Medium, and Large HMIWI
----------------------------------------------------------------------------------------------------------------
Emission limits HMIWI size
Pollutant Units (7 percent --------------------------------------------------------
oxygen dry basis) Small Medium Large
----------------------------------------------------------------------------------------------------------------
1. Units for which construction is commenced after June 20, 1996 but no later than February 6, 2007 or for which
modification is commenced on or after March 16, 1998 but no later than [THE DATE 6 MONTHS AFTER PROMULGATION OF
THE FINAL RULE]
----------------------------------------------------------------------------------------------------------------
Particulate matter............. Milligrams per dry 41 (0.018)....... 21 (0.0090)...... 21 (0.0090).
standard cubic meter
(grains per dry
standard cubic foot).
Carbon monoxide................ Parts per million by 32 \1\........... 32 \1\........... 32 \1\.
volume.
Dioxins/furans................. Nanograms per dry 111 (49) or 2.1 20 (8.7) or 0.53 20 (8.7) or 0.53
standard cubic meter (0.92). (0.23). (0.23).
total dioxins/furans
(grains per billion
dry standard cubic
feet) or nanograms
per dry standard
cubic meter TEQ
(grains per billion
dry standard cubic
feet).
Hydrogen chloride.............. Parts per million by 15 or 99%........ 15 or 99%........ 15 or 99%.
volume or percent
reduction.
Sulfur dioxide................. Parts per million by 46 \1\........... 46 \1\........... 46 \1\.
volume.
Nitrogen oxides................ Parts per million by 225 \1\.......... 225 \1\.......... 225 \1\.
volume.
Lead........................... Milligrams per dry 0.78 \1\ (0.34) 0.060 (0.026) or 0.060 (0.026) or
standard cubic meter or 71%. 98%. 98%.
(grains per thousand
dry standard cubic
feet) or percent
reduction.
Cadmium........................ Milligrams per dry 0.11 \1\ (0.048) 0.030 (0.013) or 0.030 (0.013) or
standard cubic meter or 66%. 93%. 93%.
(grains per thousand
dry standard cubic
feet) or percent
reduction.
Mercury........................ Milligrams per dry 0.47 \1\ (0.21) 0.45 \1\ (0.20) 0.45 \1\ (0.20)
standard cubic meter or 87%. or 87%. or 87%.
(grains per thousand
dry standard cubic
feet) or percent
reduction.
----------------------------------------------------------------------------------------------------------------
2. Units for which construction is commenced after February 6, 2007 or for which modification is commenced after
[THE DATE 6 MONTHS AFTER PROMULGATION OF THE FINAL RULE]
----------------------------------------------------------------------------------------------------------------
Particulate matter............. Milligrams per dry 41 (0.018)....... 21 (0.0090)...... 21 (0.0090).
standard cubic meter
(grains per dry
standard cubic foot).
Carbon monoxide................ Parts per million by 25............... 25............... 25.
volume.
Dioxins/furans................. Nanograms per dry 111 (49) or 2.0 16 (7.0) or 0.21 16 (7.0) or 0.21
standard cubic meter (0.87). (0.092). (0.092).
total dioxins/furans
(grains per billion
dry standard cubic
feet) or nanograms
per dry standard
cubic meter TEQ
(grains per billion
dry standard cubic
feet).
Hydrogen chloride.............. Parts per million by 15 or 99%........ 15 or 99%........ 15 or 99%.
volume or percent
reduction.
Sulfur dioxide................. Parts per million by 28............... 21............... 21.
volume.
Nitrogen oxides................ Parts per million by 212.............. 212.............. 212.
volume.
Lead........................... Milligrams per dry 0.64 (0.28) or 0.060 (0.026) or 0.060 (0.026) or
standard cubic meter 71%. 99%. 99%.
(grains per thousand
dry standard cubic
feet) or percent
reduction.
[[Page 5550]]
Cadmium........................ Milligrams per dry 0.060 (0.026) or 0.0050 (0.0022) 0.0050 (0.0022)
standard cubic meter 74%. or 99%. or 99%.
(grains per thousand
dry standard cubic
feet) or percent
reduction.
Mercury........................ Milligrams per dry 0.33 (0.14) or 0.19 (0.083) or 0.19 (0.083) or
standard cubic meter 96%. 96%. 96%.
(grains per thousand
dry standard cubic
feet) or percent
reduction.
----------------------------------------------------------------------------------------------------------------
\1\ Emission limit is less stringent than the corresponding limit for existing sources contained in subpart Ce.
Sources that would be subject to the emission limits in this table also would be subject to regulation under
State plans or Federal plans that would implement subpart Ce and would be subject to limits at least as
stringent as those in subpart Ce.
[FR Doc. E7-1617 Filed 2-5-07; 8:45 am]
BILLING CODE 6560-50-P