Standards of Performance for New Stationary Sources and Emission Guidelines for Existing Sources
[Federal Register: December 19, 1995 (Volume 60, Number 243)]
[Rules and Regulations]
[Page 65387-65436]
>From the Federal Register Online via GPO Access [wais.access.gpo.gov]
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 60
[AD-FRL-5327-5]
RIN 2060-AD00
Standards of Performance for New Stationary Sources and Emission
Guidelines for Existing Sources
Municipal Waste Combustors
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
SUMMARY: This action adds standards of performance for new municipal
waste combustor (MWC) units and emission guidelines for existing MWC's.
The standards and guidelines implement sections 111 and 129 of the
Clean Air Act and are based on the Administrator's determination that
MWC's cause, or contribute significantly to, air pollution that may
reasonably be anticipated to endanger public health or welfare. The
standards and guidelines apply to MWC units at plants with aggregate
capacities to combust greater than 35 megagrams per day (Mg/day)
(approximately 40 tons per day) of municipal solid waste (MSW) and
require sources to achieve emission levels reflecting the maximum
degree of reduction in emissions of air pollutants that the
Administrator determined is achievable, taking into consideration the
cost of achieving such emission reduction, and any non-air-quality
health and environmental impacts and energy requirements. The
promulgated standards and guidelines establish emission levels for MWC
organics (dioxins/furans), MWC metals (cadmium (Cd), lead (Pb), mercury
(Hg), particulate matter (PM), and opacity), MWC acid gases (hydrogen
chloride (HCl) and sulfur dioxide (SO2)), nitrogen oxides
(NOX), and MWC fugitive ash emissions. Some of the pollutants
being regulated are considered to be carcinogens and at sufficient
concentrations can cause toxic effects following exposure. The
standards and guidelines also establish requirements for MWC operating
practices (carbon monoxide (CO), load, flue gas temperature at the PM
control device inlet, and operator training/certification).
Additionally, the standards for new MWC plants also require a siting
analysis and materials separation plan.
DATES: Effective Dates. June 19, 1996 for the standards for new sources
(Secs. 60.50b through 60.59b) and December 19, 1995 for the emission
guidelines for existing sources (Secs. 60.30b through 60.39b). The
incorporation by reference of certain publications listed in the
regulations is approved by the Director of the Federal Register as of
June 19, 1996 for the standards for new sources. See table 3 of this
preamble for a summary of the retrofit schedules for existing MWC
sources. See SUPPLEMENTARY INFORMATION for a discussion of the schedule
for judicial review.
Comments. Comments on the Information Collection Request (ICR)
document associated with the final standards for new sources are
requested, as discussed in section VI.B of this preamble. Comments on
the ICR document must be received on or before February 20, 1996. Refer
to Section VI.B for further information on this request for comment.
ADDRESSES: Comments. As noted above, comments on the ICR document
[[Page 65388]]
associated with the final standards for new source are requested. See
section VI.B and the SUPPLEMENTARY INFORMATION section of this preamble
for further information on obtaining a copy of the ICR document and
addresses for submitting comments on the ICR document.
Background Information. The principal background information for
the final standards and guidelines includes: (1) A background
information document (BID) entitled, ``Municipal Waste Combustion:
Background Information for Promulgated Standards and Guidelines--
Summary of Public Comments and Responses'' (EPA-453/R-95-0136), which
contains a summary of all the significant public comments submitted
regarding the proposed standards and guidelines, the EPA's response to
these comments, and a summary of the changes made to the standards and
guidelines as a result of the comments; and (2) several technical
documents listed under SUPPLEMENTARY INFORMATION, including all of the
background information documents that supported the proposal and
promulgation of the subpart Ea standards and subpart Ca guidelines. A
document entitled ``FACT SHEET: New Municipal Waste Combustors--Subpart
Eb Standards,'' which succinctly summarizes the final standards, and a
document entitled ``FACT SHEET: Existing Municipal Waste Combustors--
Subpart Cb Emission Guidelines,'' which succinctly summarizes the
guidelines, are also available. See SUPPLEMENTARY INFORMATION for
instructions and addresses for obtaining these documents.
Docket. Docket Nos. A-90-45 and A-89-08, containing supporting
information used in developing the standards and guidelines, are
available for public inspection and copying between 8:00 a.m. and 4:00
p.m., Monday through Friday except for Federal holidays at the
following address: U.S. Environmental Protection Agency, Air and
Radiation Docket and Information Center (Mail Code 6102), 401 M Street
SW, Washington DC 20460 [phone: (202) 260-7548]. The docket is located
at the above address in room M-1500, Waterside Mall (ground floor,
central mall). A reasonable fee may be charged for copying.
FOR FURTHER INFORMATION CONTACT: Mr. Walter Stevenson at (919) 541-5264
or Mr. Fred Porter at (919) 541-5251, Combustion Group, Emission
Standards Division (MD-13), U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina 27711.
SUPPLEMENTARY INFORMATION:
Background Information.
On December 20, 1989, the EPA proposed standards and guidelines for
MWC's in subparts Ea and Ca of 40 CFR 60, respectively. The subparts Ea
and Ca were promulgated on February 11, 1991 and were developed under
authority of paragraph (b) of section 111 of the Clean Air Act of 1977.
The 1990 Amendments to the Clean Air Act required the EPA to review
these emission standards and guidelines and determine if they were
fully consistent with the requirements of section 129. The EPA reviewed
the subpart Ea standards and subpart Ca guidelines and concluded that
they were not fully consistent with the requirements of section 129.
Therefore, the EPA proposed to revise the standards and guidelines in a
September 20, 1994 proposal to make the standards and guidelines fully
consistent with the requirements of section 129. Municipal waste
combustors that begin construction after September 20, 1994 or that
begin modification or reconstruction after June 19, 1996 and that meet
all other applicability criteria are subject to the revised standards
(subpart Eb). Municipal waste combustors that were constructed on or
before September 20, 1994 and that meet all other applicability
criteria are subject to the revised guidelines (subpart Cb). Municipal
waste combustors that were constructed after December 20, 1989 and on
or before September 20, 1994 and that meet all other applicability
criteria are subject to both the subpart Ea standards (1991 standards
for new sources) and the subpart Cb guidelines (1995 retrofit
guidelines for existing sources). In this final rule, the EPA is
withdrawing the subpart Ca guidelines (1991 guidelines for existing
sources). In a separate action in today's Federal Register the EPA is
publishing a direct final rule amending the text of subpart Ea.
This Federal Register final rule discusses: (1) The standards for
new MWC's, (2) the guidelines for existing MWC's, (3) the withdrawal of
the 1991 subpart Ca guidelines for existing MWC's, and (4) a request
for public comment on the ICR document. This preamble and regulatory
text are available on the EPA's Technology Transfer Network (TTN)
electronic bulletin board. Also available on the EPA's TTN are FACT
SHEETS, which summarize the final standards and guidelines. They are
suggested reading for persons requiring an overview of the standards
and guidelines. The FACT SHEETS can also be obtained by calling Donna
Collins at (919) 541-5578. The TTN contains 18 electronic bulletin
boards, and the following 5 items are included in the Clean Air Act
Amendments (CAAA) bulletin board under menu item ``Recently Signed
Rules'' in file ``MWC2.ZIP'':
(1) ``FACT SHEET: New Municipal Waste Combustors--Subpart Eb
Standards (1995).''
(2) ``FACT SHEET: Existing Municipal Waste Combustors--Subpart Cb
Emission Guidelines (1995).''
(3) Federal Register notice for this promulgation: ``Standards of
Performance for New Stationary Sources and Emission Guidelines for
Existing Sources: Municipal Waste Combustors'' (this document).
(4) ``Municipal Waste Combustion: Background Information for
Promulgated Standards and Guidelines--Summary of Public Comments and
Responses,'' EPA-453/R-95-0136.
(5) Information Collection Request document for these standards for
new sources: ``Standard Form 83 Supporting Statement for ICR No.
1506.5--1995 Standards for New Municipal Waste Combustors (Subpart
Eb),'' September 29, 1995.
The TTN is accessible 24 hours per day, 7 days per week except
Monday morning from 8:00 a.m. to 12:00 p.m. when the system is updated.
The service is free except for the cost of the phone call. Dial (919)
541-5742 to access the TTN. The TTN is compatible with up to a 14,400
bits-per-second (bps) modem. An alternative way to access the TTN is by
``telenet,'' using access code ``ttnbbs.rtpnc.epa.gov''. Further
instructions for accessing the TTN can be obtained by calling the help
desk at (919) 541-5384.
Documents in the Docket. The background information for today's
promulgation includes all of the documents that supported the proposal
and promulgation of the subpart Ea standards and subpart Ca guidelines
(docket No. A-90-45 and docket No. A-89-08). Key background information
documents used in developing the subpart Ea standards, the subpart Ca
guidelines, and today's promulgated standards and guidelines are as
follows:
(1) ``Municipal Waste Combustors--Background Information for
Proposed Standards: 111(b) Model Plant Description and Cost Report,''
EPA-450/3-89-27b, August 1989;
(2) ``Municipal Waste Combustors--Background Information for
Proposed Standards: Post-Combustion Technology Performance,'' EPA-450/
3-89-27c, August 1989;
(3) ``Municipal Waste Combustion Assessment: Combustion Control at
[[Page 65389]]
Existing Facilities,'' EPA-600/8-89-057, August 1989;
(4) ``Municipal Waste Combustion Assessment, Technical Basis for
Good Combustion Practices,'' EPA-600/8-89-063, August 1989;
(5) ``Municipal Waste Combustors--Background Information for
Proposed Standards: Control of NOXEmissions,'' EPA-450/3-89-27d,
August 1989;
(6) ``Municipal Waste Combustors--Background Information for
Proposed Standards: Cost Procedures,'' EPA-450/3-89-27a, August 1989;
(7) ``Economic Impact Analysis for Proposed Emission Standards and
Guidelines for Municipal Waste Combustors,'' EPA-450/3-91-029, March
1994;
(8) ``Municipal Waste Combustors--Background Information for
Proposed Guidelines for Existing Facilities,'' EPA-450/3-89-27e, August
1989;
(9) ``Municipal Waste Combustion: Background Information for
Promulgated Standards and Guidelines--Summary of Public Comments and
Responses,'' EPA-453/R-95-0136, 1995.
These documents and additional technical information are contained
in dockets A-90-45 and A-89-08. Docket materials are available for
inspection and copying as described in the ADDRESSES section of this
preamble.
Judicial Review. Under section 307(b)(1) of the Clean Air Act,
judicial review of the actions taken by this notice is available by
filing of a petition for review in the U.S. Court of Appeals for the
District of Columbia Circuit within 60 days of today's publication of
this rule. Under section 307(b)(2) of the Clean Air Act, the
requirements that are in today's notice may not be challenged later in
the civil or criminal proceedings brought by the EPA to enforce these
requirements (42 U.S.C. 7607(b)).
Preamble Outline. The following outline is provided to aid in
locating information in the introductory text (preamble) to the final
standards and guidelines.
I. Acronyms, Abbreviations, and Measurement Units
A. Acronyms
B. Abbreviations and Measurement Units
II. Background and Withdrawal of the 1991 Subpart Ca Emission
Guidelines
III. Summary of Considerations in Developing the 1995 Standards for New
Sources and Guidelines for Existing Sources
A. Purpose of the Standards and Guidelines
B. Technical Basis of the Standards and Guidelines
C. Stakeholders and Public Involvement
IV. Standards of Performance for New Sources (1995)--Summary of the
Standards, Impacts of the Standards, and Significant Issues and Changes
to the Proposed Standards
A. Summary of the Standards
B. Significant Issues and Changes to the Proposed Standards
Applicability
Emission Limits for MWC Metals, Acid Gases, Organics,
Nitrogen Oxides, and Ash Fugitive Emissions
Good Combustion Practices
Operator Training and Certification
Air Curtain Incinerators
Siting Analysis/Materials Separation Plan
Compliance and Performance Testing
Reporting and Recordkeeping Requirements
C. Impacts of the Standards
V. Guidelines for Existing Sources (1995)--Summary of the Guidelines,
Impacts of the Guidelines, and Significant Issues and Changes to the
Proposed Guidelines
A. Summary of the Guidelines
B. Significant Issues and Changes to the Proposed Guidelines
Designated Facilities
Emission Limits for MWC Metals, Acid Gases, Organics,
Nitrogen Oxides, and Fugitive Ash Emissions
Good Combustion Practices
Operator Training and Certification
Air Curtain Incinerators
Compliance and Performance Testing
Reporting and Recordkeeping Requirements and Compliance
Schedules
C. Impacts of the Guidelines
VI. Administrative Requirements
A. Docket
B. Paperwork Reduction Act
C. Executive Order 12866
D. Unfunded Mandates Act
E. Executive Order 12875
F. Regulatory Flexibility Act
G. Clean Air Act Procedural Requirements
I. Acronyms, Abbreviations, and Measurement Units
The following definitions, acronyms, and measurement units are
provided to clarify the preamble to the final standards and guidelines.
A. Acronyms
ASME American Society of Mechanical Engineers
BID Background Information Document
CEMS continuous emissions monitoring system(s)
COMS continuous opacity monitoring system(s) dioxins/furans
polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans
DSI dry sorbent injection
EPA U.S. Environmental Protection Agency
ESP electrostatic precipitator
FF fabric filter
GCP good combustion practices
ICR information collection request
MACT maximum achievable control technology
MSW municipal solid waste
MWC municipal waste combustor
MWI medical waste incinerator
NSR New Source Review
NOXnitrogen oxides
OAQPS Office of Air Quality Planning Standards
OMB Office of Management and Budget
PM particulate matter
RDF refuse-derived fuel
RFA Regulatory Flexibility Act
SD spray dryer
SNCR selective noncatalytic reduction
TEQ basis 2,3,7,8-tetrachlorinated dibenzo-p-dioxin toxic equivalent
based on the 1989 international toxic equivalency factors
B. Abbreviations and Measurement Units
deg.C=degrees Celsius (degrees Fahrenheit= deg.C*9/5+32)
Cd=cadmium
CO=carbon monoxide
CO<INF>2=carbon dioxide
dscf=dry standard cubic feet (at 14.7 pounds per square inch, 68
deg.F)
dscm=dry standard cubic meters (at 14 pounds per square inch, 68
deg.F)
g=gram (454 grams per pound)
g/yr=grams per year
gr=grains (7,000 grains per pound)
HCl=hydrogen chloride
Hg=mercury
kg=kilogram (0.454 kilograms per pound)
kg/yr=kilograms per year
m3=cubic meter (35.3 cubic feet per cubic meter)
mg=milligrams (10<SUP>-3 grams)
Mg=megagram (1.1 tons)
Mg/d=megagrams per day
Mg/yr=megagrams per year
ng=nanogram (10<SUP>-9 grams)
Pb=lead
ppmv=parts per million by volume
SO2=sulfur dioxide
tons/d=tons per day
tons/yr=tons per year
total mass basis (dioxins/furans=total mass of tetra- through octachlorinated
dibenzo-p-dioxins and dibzofurans
II. Background and Withdrawal of the 1991 Subpart Ca Emission
Guidelines
By the mid-1980's, several studies had been performed to determine
whether MWC emissions should be regulated and, if so, under what
section of the Clean Air Act. As set forth in the Advanced Notice of
Proposed Rulemaking (52 FR 25399, July 7, 1987), the EPA decided to
regulate air emissions from MWC's under section 111 of the Clean Air
Act, and to base the
[[Page 65390]]
regulation on best demonstrated technology, as required by section 111.
On December 20, 1989, the EPA proposed standards for new MWC's and
guidelines for existing MWC's (54 FR 52251 and 54 FR 52209,
respectively). On November 15, 1990, 1990 Amendments to the Clean Air
Act were enacted and added section 129 to the Clean Air Act. Section
129 of the Clean Air Act specifies that revised standards and
guidelines must be developed for MWC's in accordance with the
requirements of both section 111 and new section 129. Section 129
further specifies that revised standards and guidelines be developed
for both large and small MWC plants and that the revised standards and
guidelines must reflect more restrictive performance levels. Section
129 includes a schedule for revising the 1991 standards and guidelines.
When the EPA did not comply with the section 129 schedule, the
Sierra Club, the Natural Resources Defense Council, and the Integrated
Waste Services Association filed complaints with the U.S. District
Court for the Eastern District of New York. The resulting consent
decree required the EPA Administrator to sign a notice of proposed
rulemaking not later than September 1, 1994 and a notice of
promulgation not later than October 31, 1995 (Nos. CV-92-2093, CV-93-
0284, and CV-93-5144). The proposal notice for the standards and
guidelines was signed as scheduled and published on September 20, 1994
(59 FR 48198 and 59 FR 48228, respectively). This notice responds to
the requirement for the Administrator to sign the final standards and
guidelines by October 31, 1995.
The standards and guidelines promulgated on February 11, 1991 (56
FR 5488 and 56 FR 5514, respectively) apply to only large MWC's
(capacities above 225 Mg/day) and reflect best demonstrated technology.
Today's notice promulgates revised standards and guidelines that are
fully consistent with sections 111 and 129 of the Clean Air Act and
extend coverage of the revised standards and guidelines to MWC units
located at MWC plants with aggregate plant capacity above 35 Mg/day.
Today's promulgated standards for new sources are more stringent
than the standards promulgated on February 11, 1991. Today's
promulgated standards will apply to plants for which construction
commenced after September 20, 1994 or for which reconstruction or
modification commenced after June 19, 1996. The guidelines will apply
to all MWC's constructed prior to September 20, 1994. The February 11,
1991 subpart Ea standards will remain in effect for plants constructed,
modified, or reconstructed between December 20, 1989 and September 20,
1994. Sources subject to the February 11, 1991 subpart Ea standards are
also subject to the guidelines being promulgated today under subpart
Cb. In some cases, the promulgated subpart Cb guidelines are more
stringent than the existing subpart Ea standards. The control
technologies being used to meet the emission limits included in the
1991 subpart Ea standards will be able to comply with the promulgated
subpart Cb guidelines, except supplemental controls would be required
to reduce Hg emissions and fugitive ash emissions. The direct final
rule also being published in today's Federal Register will provide
consistency between the subpart Ea and Cb rules.
Today's promulgated guidelines under subpart Cb for existing
sources are more stringent than the guidelines promulgated under
subpart Ca on February 11, 1991. Today's promulgated guidelines will
apply to MWC's for which construction commenced on or before September
20, 1994. Today's promulgated guidelines are based on maximum
achievable control technology, or MACT, and will require MWC plants to
purchase and install different types of air pollution control equipment
than the best demonstrated technology-based guidelines promulgated in
1991 under subpart Ca. In consideration of public comments, which
supported the withdrawal of subpart Ca, and to satisfy the MACT
requirements of section 129 of the Clean Air Act, the EPA is
withdrawing the 1991 subpart Ca guidelines as a part of today's action.
III. Summary of Considerations in Developing the 1995 Standards for New
Sources and Guidelines for Existing Sources
A. Purpose of the Standards and Guidelines
Under sections 111 and 129 of the Clean Air Act, the EPA is
required to develop and adopt performance standards and guidelines for
MWC's. Congress specifically added section 129 to the Clean Air Act to
address public concerns about MWC's and other solid waste combustion
units. Under section 111, performance standards and guidelines must be
developed for new and existing stationary sources that may contribute
to air pollution and that may reasonably be anticipated to endanger
public health or welfare. Under section 129 of the Clean Air Act, the
standards and guidelines adopted for MWC's must be based on MACT.
Independent of Clean Air Act requirements, the general public is
concerned about emissions from all sources including MWC's. This is
understandable considering (1) about two-thirds of the MWC population
is located in air quality nonattainment areas with high population
densities, and (2) the EPA's 1994 MWC Dioxin Survey identified a
limited number of older poorly controlled MWC's with atypically high
dioxin/furan emissions (interim corrective actions have been taken at
these MWC's).
The MWC industry has aggressively controlled new MWC plants built
since 1990, and almost half of the existing population currently is
equipped with high efficiency air pollution control equipment. The
other older half of the population has control equipment with lower
efficiency. As mentioned earlier, health effects are associated with
many of the pollutants emitted from MWC's, and the standards and
guidelines being promulgated today will bring all MWC units up to the
same high performance level.
The EPA estimates that in the United States, there are about 307
operating MWC units at 128 plants, providing a total U.S. MSW
combustion capacity of about 94,000 Mg/day. Approximately 16 percent of
MSW generated in the United States is combusted.
Emissions from MWC's contain organics (dioxins/furans), metals (Cd,
Pb, Hg, PM, and opacity), acid gases (Hcl and SO2), and NO<INF>X.
These pollutants can have adverse effects on both public health and
welfare. The EPA recently released a draft report reassessing the
health effects of human exposure to dioxins/furans. In the draft
report, which is currently undergoing review, MWC's are identified as
one source of dioxin/furan emissions. Other MWC emissions of principal
concern include Pb, Cd, and Hg. Acid gas and NOXemissions
contribute to acid rain when emissions of SO2 and NOXare
chemically transformed in the atmosphere into sulfuric and nitric acids
and return to earth as wet deposition such as rain, fog, or snow, or as
dry deposition such as fine particles or gases. Acid deposition damages
lakes and harms forests and buildings. Nitrogen oxides also contribute
to low-level ozone and urban area smog formation.
Today's standards and guidelines are set forth as emission limits
and will significantly reduce MWC emissions.
[[Page 65391]]
B. Technical Basis of Standards and Guidelines
Section 129(a)(2) of the Clean Air Act requires the revised
standards for new MWC's and revised guidelines for existing MWC's to
reflect the maximum degree of reduction in emissions of designated air
pollutants, taking into consideration the cost of achieving such
emission reduction, and any non-air-quality health and environmental
impacts and energy requirements that the Administrator determines are
achievable for a particular category of sources. (This control level is
commonly referred to as the ``maximum achievable control technology, or
``MACT''.) Section 129 also provides that standards for new sources may
not be less stringent than the emissions control achieved in practice
by the best controlled similar unit. This is commonly referred to as
the ``MACT floor'' for new MWC units. Additionally, section 129
provides that the emission limitations in the guidelines for existing
MWC's may not be less stringent than the average emission limitations
achieved by the best performing 12 percent of units in the category.
This is commonly referred to as the ``MACT floor'' for existing MWC
units. Emission control options less stringent than the MACT floor can
not be considered in developing section 129 standards and guidelines.
Technical data on the number and size of MWC's, control
technologies in use, permit emission limits, and emission test data
were used to determine the MACT floor for new and existing MWC's and to
define control alternatives. The types of data EPA considered in
selecting final standards and guidelines included the following: (1)
Over 100 MWC plant-specific questionnaires; (2) emissions information
from literature, and State and local agencies; and (3) EPA and industry
test reports. Overall, the EPA used performance test data from over 60
MWC plants to develop the standards and guidelines. After proposal, the
EPA reviewed additional data submitted with public comments on the
proposal and data that EPA gathered from States and industry. Based on
the new information, the EPA reviewed both the proposed MACT
determinations for new and existing MWC's and the regulatory
alternatives. The reassessment of the standards and guidelines in light
of the new data resulted in the EPA revising the MACT emission rates
for some pollutants.
The most significant changes to the standards and guidelines since
proposal are summarized in sections IV.B and V.B., respectively, of
this preamble. The rationales for these changes as well as other
changes are summarized in the preamble and discussed in more detail in
the BID. In keeping with the Administrator's ``reinventing government''
initiative, several of the changes to the guidelines and standards were
made to streamline the regulations and provide increased flexibility
while optimizing environmental control by using common sense
initiatives. Examples of these changes include the following: (1)
Reduced dioxin/furan testing for MWC plants with low dioxin/furan
emission levels; (2) NOXguidelines for large MWC plants that
allow plants to use an emissions averaging plan to demonstrate
compliance for two or more existing MWC units located at the same
facility; (3) clarification of siting requirements for new MWC's; (4)
providing additional time for MWC operators to obtain operator training
and certification; (5) replacing quarterly reporting with annual
reporting (semiannual reporting if noncompliance); (6) revised text to
clarify that the regulations do not apply to MWC plants with combustion
capacity less than 35 Mg/day; (7) exemption for plants firing small
amounts of MSW (10 Mg/day or less); (8) exemption for combustion of
clean wood; and (9) allowing certain records to be maintained in either
electronic or paper format without duplication. All of these changes
are discussed further in sections IV and V of this preamble, and
represent changes that improve the effectiveness and efficiency of the
standards and guidelines without any reduction in environmental
protection.
C. Stakeholders and Public Involvement
Prior to proposal, in accordance with section 117 of the Clean Air
Act, the EPA consulated with advisory committees, independent experts,
Federal departments and agencies, and owners, operators, and
manufacturers of MWC's. Numerous discussions were held with
governmental entities, industry representatives, and environmental
groups including, but not limited to, the following groups: the U.S.
Conference of Majors, the National League of Cities, the National
Association of Counties, the Municipal Waste Management Association,
the Solid Waste Association of North America, the Integrated Waste
Services Association, the Sierra Club, and the Natural Resources
Defense Council.
The standards and guidelines being adopted today were proposed in
the Federal Register on September 20, 1994 (59 FR 48198 and 59 FR
48228, respectively). The preambles for the proposed standards and
guidelines describe the rationale for the proposed standards and
guidelines. After proposal, the EPA provided interested persons the
opportunity to comment through a written comment period. The public
comment period was from September 20, 1994 to November 21, 1994.
Comments were received from private citizens, industry representatives,
environmental groups, and governmental entities. The comments have been
carefully considered, and changes have been made in the standards and
guidelines where appropriate. Sections IV and V of this preamble
discuss the major revisions to the standards and guidelines to address
the commenters' concerns.
IV. Standards of Performance for New Sources (1995)--Summary of the
Standards, Impacts of the Standards, and Significant Issues and Changes
to the Proposed Standards
This section presents a summary of the final standards, including
identification of the source category and pollutants being regulated,
and presentation of the final emission limits and their associated
performance testing, monitoring, recordkeeping and reporting
requirements. This section also discusses the most significant changes
to the proposed standards. Also discussed are the impacts of the final
standards.
A. Summary of the Standards
The final standards (subpart Eb) apply to each new MWC unit located
at an MWC facility that has an aggregate plant capacity to combust over
35 Mg/day of MSW, for which construction commenced after September 20,
1994 or modification or reconstruction commenced after June 19, 1996.
Municipal waste combustors that commenced construction on or before
September 20, 1994 are not covered under the subpart Eb standards.
Municipal waste combustors constructed on or before September 20, 1994
are considered existing sources and are subject to the guidelines that
are addressed in section V of this notice.
An MWC is defined as any setting or equipment that combusts MSW
including air curtain incinerators. Municipal solid waste combustion
includes the direct combustion of MSW or the combustion of MSW gases
from pyrolysis or gasification. The MWC unit includes any type of
setting or equipment including combustion equipment with or without
heat recovery.
[[Page 65392]]
Municipal solid waste is defined as a mixture or a single-item
waste stream of household, commercial, and/or institutional discards.
This would include materials such as paper, yard waste, plastics,
leather, rubber, glass, metals, and other combustible and
noncombustible materials. The final MSW definition is revised slightly
from proposal to make it clear that MSW does not include used motor
oil; sewage sludge; wood pallets; construction, renovation, and
demolition wastes (including but not limited to railroad ties and
telephone poles); clean wood; industrial process or manufacturing
wastes; medical waste; or motor vehicles. Although these wastes are not
MSW, they can be intermixed with MSW and can be combusted in MWC
plants. The regulations do not prohibit their combustion. The
definition of MSW includes RDF, which is municipal solid waste that is
shredded (or pelletized) before combustion. Any medical, industrial, or
other type of waste combustor plant with capability to combust greater
than 35 Mg/day of MSW and is in compliance with a federally enforceable
permit to combust less than 10 Mg/day of MSW is not covered by this
standard. Furthermore, cofired MWC plants that combust less than 30
percent MSW (on a calendar quarter basis) are exempt. A summary of the
final standards is presented in table 1. In table 1, significant
revisions made since proposal are marked with an asterisk (*) and are
discussed in section IV.B.
Table 1.--Summary of Standards for new MWC's (Subpart Eb)<SUP>a
[* indicates a significant change since proposal and the change is
discussed in this preamble]
Applicability
The final standards apply to new MWC
units located at plants with
capacities to combust greater than 35
Mg/day of residential, commercial, and/
or institutional discards. Industrial
manufacturing discards are not covered
by the standards. Any medical,
industrial manufacturing, municipal,
or other type of waste combustor plant
with capacity to combust greater than
35 Mg/day of MSW and with a federally
enforceable permit to combust less
than 10 Mg/day of MSW is not covered.*
Plant Size (MSW combustion capacity) Requirement.
<ls-thn-eq>35 Mg/day*.................. Not covered by standards.
>Mg/day but <ls-thn-eq>225 Mg/day Subject to provisions listed
(referred to as small MWC plants). below.
>225 Mg/day (referred to as large MWC Subject to provisions listed
plants). below.
Good Combustion Practices
<bullet> Applies to large and small MWC plants.
<bullet> A site-specific operator training manual is required to be
developed and made available for MWC personnel.
<bullet> The EPA or State MWC operator training course must be completed
by the MWC chief facility operator, shift supervisors, and control room
operators.
<bullet> The ASME (or State-equivalent) operator certification must be
obtained by the MWC chief facility operator (mandatory), shift
supervisors (mandatory), and control room operators (optional).*
<bullet> The MWC load level is required to be measured and not to exceed
110 percent of the maximum load level measured during the most recent
dioxin/furan performance test.
<bullet> The PM control device inlet flue gas temperature is required to
be measured and not to exceed the temperature 17 deg.C above the
maximum temperature measured during the most recent dioxin/furan
performance test.
<bullet> The CO level is required to be measured using CEMS, and the
concentration in the flue gas is required not to exceed the following:
Averaging
MWC type CO level time
(hours)
Modular starved-air and excess-air. 50 ppmv............... 4
Mass burn waterwall and refractory. 100 ppmv.............. 4
Mass burn rotary refractory........ 100 ppmv.............. 4
Fluidized-bed combustion........... 100 ppmv.............. 4
Pulverized coal/RDF mixed fuel- 150 ppmv*............. 4
fired.
Spreader stoker coal/RDF mixed fuel- 150 ppmv*............. 24
fired.
RDF stoker......................... 150 ppmv.............. 24
Mass burn rotary waterwall......... 100 ppmv.............. 24
MWC Organic Emissions (measured as
total mass dioxins/furans):
<bullet> Dioxins/furans
(performance test by EPA Reference
Method 23)
Large and small MWC plants......... 13 ng/dscm total mass
(mandatory) or 7 ng/
dscm total mass
(optional to qualify
for less frequent
testing).<SUP>*b.
[[Page 65393]]
<bullet> Basis for dioxin/furan GCP and SD/FF/carbon
limit injection.
MWC Metal Emissions:
<bullet> PM (performance test by
EPA Reference Method 5)
Large and small MWC plants....... 24 mg/dscm (0.010 gr/
dscf).*
<bullet> Opacity (performance test
by EPA Reference Method 9)
Large and small MWC plants....... 10 percent (6-minute
average)
<bullet> Cd (performance test by
EPA Reference Method 29)
Large and small MWC plants....... 0.020 mg/dscm (8.7 gr/
million dscf).*
<bullet> Pb (performance test by
EPA Reference Method 29)
Large and small MWC plants....... 0.20 mg/dscm (87 gr/
million dscf).*
<bullet> Hg (performance test by
EPA Reference Method 29)
Large and small MWC plants....... 0.080 mg/dscm (35 gr/
million dscf) or 85-
percent reduction in
Hg emissions
<bullet> Basis for PM, opacity, Cd,
Pb, and Hg limits
Large and small MWC plants....... See basis for dioxin/
furan limit
MWC Acid Gas Emissions:
<bullet> SO2 (performance test by
CEMS)
Large and small MWC plants....... 30 ppmv or 80-percent
reduction in SO2
emissions
<bullet> HCl (performance test by
EPA Reference Method 26)
Large and small MWC plants....... 25 ppmv or 95-percent
reduction in HCl
emissions
<bullet> Basis for SO2 and HCl See basis for dioxin/
limits furan limit..
Nitrogen Oxides Emissions:
<bullet> NOx (performance test by
CEMS)
Large MWC plants................. 150 ppmv, except 180
ppmv is allowed for
the first year of
operation.*
Small MWC plants................. No NOXcontrol
requirement
<bullet> Basis for NOXlimit
Large MWC plants................. SNCR
Small MWC plants................. No NOXcontrol
requirement.
[[Page 65394]]
Fugitive Ash Emissions:
<bullet> Fugitive emissions
(performance test by EPA Reference
Method 22)
Large and small MWC plants....... Visible emissions less
than 5 percent of the
time from the ash
transfer system
except during
maintenance and
repair activities.*.
<bullet> Basis for fugitive Wet ash handling or
emissions limit. enclosed ash handling.
Siting Requirements:
<bullet> Large and small MWC (1) Siting analysis*,
plants. (2) materials
separation plan, and
(3) public meetings
(including response
to comments)
Performance Testing and Monitoring
Requirements:
<bullet> Reporting frequency..... Annual (semiannual if
violation).*
<bullet> Load, flue gas Continuous monitoring,
temperature. 4-hour block
arithmetic average.
<bullet> CO...................... CEMS, 4-hour block or
24-hour daily
arithmetic average,
as applicable.
<bullet> Dioxins/furans, PM, Cd,
Pb, HC1, and Hg
Large MWC plants................. Annual stack test (see
reduced testing
option for low
emitters of dioxins/
furans).*
Small MWC plants................. Annual or third year
stack test.*
<bullet> Opacity................. COMS (6-minute
average) and annual
stack test.
<bullet> SO2..................... CEMS, 24-hour daily
geometric mean.
[[Page 65395]]
<bullet> NOX(large MWC plants CEMS, 24-hour daily
only). arithmetic average.
<bullet> Fugitive ash emissions.. Annual test.
*=a significant change since proposal, and the change is discussed in
this preamble.
<SUP>a All concentration levels in the table are corrected to 7 percent O<INF>2,
dry basis.
<SUP>b Although not part of the dioxin/furan limit, the limit of 13 ng/dscm
total mass is equal to about 0.1 to 0.3 ng/dscm TEQ. The optional
reduced testing limit of 7 ng/dscm total mass is equal to about 0.1 to
0.2 ng/dscm TEQ.
B. Significant Issues and Changes to the Proposed Standards (Issues
were marked with the ``*'' symbol in table 1)
The most significant changes to the standards since proposal are
discussed below. Additional rationales for these changes, as well as
other changes being made are provided in the promulgation BID (EPA-453/
R-95-0136). Some of the changes made that are not discussed below
include GCP requirements, monitoring requirements, and reporting and
recordkeeping requirements.
Applicability
At proposal, an MWC plant of 35 Mg/day capacity that cofired 30
percent (10 Mg/day) or less MSW would have been exempt from the
standards. This 30 percent cofiring provision was retained in the final
rule. Additionally, a 10 Mg/day exemption has been added to the final
rule to exempt all combustion units independent of size that fire only
a small amount of MSW. In the final standards, any medical, industrial
manufacturing, or other type of waste combustor capable of combusting
more than 35 Mg/day MSW but actually combusting less than 10 Mg/day of
MSW is not subject to this rule, provided it submits an initial report
containing a copy of the plant's federally enforceable permit limiting
the amount of MSW that may be combusted by the plant to less than 10
Mg/day and keeps records on the daily weight of MSW fired.
At proposal, a cofired combustor was defined as a unit combusting a
fuel feed stream where 30 percent or less was comprised of MSW, as
measured on a 24-hour daily basis. Several commenters expressed concern
about a cofired status determination being made on a daily basis. For
example, some facilities that burn biomass material including yard
waste would have difficulty making a determination of cofired status on
a daily basis. Biomass material including yard waste (which is MSW) and
clean wood (which is not MSW) are often collected together and stored
on- or off-site for a period of time and intermixed before being
combusted. In such cases, it is difficult or impossible to determine
what percentage of the waste combusted daily was yard waste. After
considering the public comments, the EPA determined that the definition
of cofired combustor should be revised to allow for measuring the
percent MSW burned on a calendar quarterly basis. This change is
consistent with current waste refuse storage and recordkeeping
procedures.
Also under the proposal, MWC plants of 25 to 35 Mg/day capacity
were required to submit an initial notification of construction, but
they were not subject to the proposed standards or guidelines. Only MWC
plants greater than 35 Mg/day capacity were covered by the proposal. As
part of the Administrator's ``reinventing government'' initiative, the
initial notification requirement for MWC plants between 25 and 35 Mg/
day capacity was removed from the final rule to minimize the reporting
requirement for smaller plants. This change reduced reporting and
recordkeeping requirements for both the MWC and the EPA, but did not
reduce the level of environmental protection provided by the standards
and guidelines being adopted today.
Under the proposed standards, clean wood was included in the
definition of MSW. Several commenters disagreed with this decision to
cover clean wood under the MWC standards. Under the final rule, clean
wood is not considered to be MSW. Clean wood includes untreated wood or
untreated wood products including clean untreated lumber, tree stumps
(whole or chipped), and tree limbs (whole or chipped). Clean wood is
exempt from the definition of MSW because available data indicate that
combustion of clean wood results in low emission of dioxins/furans, Hg,
and other pollutants. Clean wood is predominantly an agricultural,
industrial, or other nonmunicipal solid waste; regulation of the
combustion of these types of wastes is currently being addressed under
a separate rulemaking. Clean wood does not include yard waste, which is
covered by the final MWC standards; yard waste includes grass, grass
clippings, bushes, shrubs, and clippings from bushes and shrubs that
are generated by residential, commercial/retail, institutional, or
nonmanufacturing industrial sources as part of maintenance activities
associated with yards or other private or public lands.
Emission Limits for MWC Metals, Acid Gases, Organics, Nitrogen
Oxides, and Ash Fugitive Emissions
Many commenters expressed concern as to whether the proposed
emission limits for all regulated pollutants are actually achievable by
an MWC. These commenters noted that no single MWC existed with all the
controls proposed as MACT (SD/FF/SNCR and carbon injection) and the
standards may not be achievable. Since proposal, the EPA has obtained
data from 12 new MWC units at 5 MWC plants that have recently begun
operation and all are equipped with the full set of controls proposed
as MACT (SD/FF/SNCR and carbon injection). Data from these plants show
that all proposed emission limits for all pollutants are simultaneously
being achieved. Therefore, the EPA remains convinced that properly
designed, constructed, maintained, and operated MWC plants can comply
with all pollutant emission limits included in the final standards.
For new sources, the MACT floor for each regulated pollutant was
established as the emission level achievable by the best controlled
source. To determine new source MACT for proposal, the EPA evaluated
the performance of SD/FF/SNCR/carbon injection. Since proposal, the EPA
obtained additional information regarding the performance of the
control technologies determined to be MACT (SD/FF/SNCR/carbon
injection). Based on the new information and a reevaluation of the data
used for proposal, the EPA revised the achievable performance levels
for PM, Cd, Pb, Hg, dioxins/furans, and NO<INF>X. Changes to the MACT
floor levels and the selected MACT standards resulting from these
reevaluations are discussed below.
[[Page 65396]]
a. MWC Acid Gases. The MACT floor levels and selected MACT emission
limits for MWC acid gases are the same as proposed.
b. MWC Metals. Based on comments and data received since proposal,
the EPA reassessed the achievable performance levels for PM, Cd, and Pb
by SD/FF systems. Based on this reassessment of available data, the
selected PM, Cd, and Pb MACT emission limits were revised. For both
large and small plants, the PM MACT floor and selected MACT limit were
revised to 24 mg/dscm (proposal was 15 mg/dscm). The Cd MACT floor and
selected MACT limit were revised to 0.020 mg/dscm (proposal was 0.010
mg/dscm). The Pb MACT floor and selected MACT limit were revised to
0.20 mg/dscm (proposal was 0.10 mg/dscm). The selected MACT limits for
all three pollutants were revised because, based on available data,
emission levels more stringent than these levels are not considered to
be continuously achievable.
The final MACT limits for Hg emissions for large and small plants
remain at the same levels as proposed (0.080 mg/dscm or an 85 percent
reduction in Hg emissions); however, the MACT floor level was revised.
At proposal, the MACT floor for Hg was based on use of an SD/FF system
combined with GCP. Carbon injection was not commercially operational at
any MWC. At proposal, MACT for Hg was based on use of an SD/FF system
in combination with carbon injection. This MACT selection was based on
evaluation of emission reductions, costs, and other factors, as
described in the proposal preamble (59 FR 48198, September 20, 1994).
Several commenters questioned the selection of an Hg MACT limit based
on carbon injection when carbon injection was not commercially
operated. Since proposal, data have become available for 12 new MWC
units initiating operation using carbon injection commercially, and all
were meeting the proposed Hg limits. Since carbon injection is now in
commercial operation, the EPA revised the final MACT floor for Hg to be
based on SD/FF in combination with carbon injection and GCP.
c. MWC Organics. The final emission limits for dioxins/furans for
new MWC's remain at the same level as proposed; however, the technology
basis for the floor level of control has been changed. As discussed in
section IV.B.2.b regarding MWC metals (Hg), the EPA reviewed new data
received since proposal and concluded that SD/FF combined with GCP and
carbon injection is the best emission control technology being used by
MWC's for Hg and dioxin/furan control, and is, therefore, the basis of
the final MACT floor. The data gathered prior to proposal as well as
data for new units operating with these controls show that a dioxin/
furan level of 13 ng/dscm is achievable. The final MACT emission limit
for dioxins/furans for new units at both large and small plants is
equal to the MACT floor and remains at 13 ng/dscm (total mass basis).
The format of the final dioxin/furan emission limit changed from
the proposed format. The EPA proposed a dual format for the dioxin/
furan emission limit (total or TEQ) and requested comments on the use
of this dual format. No commenters agreed with the dual format as
proposed. The EPA has selected total mass dioxin/furan emissions in the
final standards. The TEQ format is not used. There is no indication
that TEQ's would be a better measure of emissions control performance
than total dioxins/furans. Furthermore, most test data on which the
standards are based were expressed as total dioxins/furans.
Additionally, because there have been different methods for calculating
TEQ over time and the ratio of total dioxins/furans to TEQ dioxins/
furans varies among MWC's, there would be additional uncertainty in
using a TEQ data base. Refer to the promulgation preamble (56 FR 5504)
for the 1991 subpart Ea standards for additional discussion.
Although not part of the dioxin/furan limit, the limit of 13 ng/
dscm total mass is equal to about 0.1 to 0.3 ng/dscm TEQ.
In addition to the final dioxin/furan limit of 13 ng/dscm, a
provision has been added to the final standards allowing less frequent
dioxin/furan testing for new plants achieving dioxin/furan emission
levels lower than 7 ng/dscm. Data for new MWC's using SD/FF/SNCR/carbon
injection technology suggest this is a realistic goal for many new
MWC's and will encourage MWC's to optimize performance of pollution
control systems. Refer to section IV.B.7 for a description of the
alternative dioxin/furan testing schedule.
d. Nitrogen Oxides. As explained at proposal (59 FR 48198,
September 20, 1994), the combination of SD/FF, GCP, and SNCR was the
basis of the new source MACT floor for NO<INF>X. These technologies
remain the basis for the final NOXMACT floor. Since proposal, the
EPA has obtained additional NOXdata showing that large MWC plants
equipped with SNCR can continuously achieve an emission level of 150
ppmv over a 24-hour averaging period. The new data were obtained from
the same plant that was the basis of the proposed NOXemission
level of 180 ppmv. The new data are representative of what NOX
emission level can be achieved after a plant has had a period of time
to adjust to operation with the SNCR system. Applications of SNCR
typically require some site-specific fine-tuning to achieve optimum
performance levels. Based on the revised data, a two-phase standard is
being adopted. The final NOXstandard for MWC's at large plants
allows time to ``fine-tune'' the SNCR system. The final standard for
MWC's at large plants is 180 ppmv (24-hour averaging period) for the
first year of operation, and 150 ppmv (24-hour averaging period)
thereafter.
The final standards do not require NOXcontrol for MWC's at
small plants.
e. MWC Fugitive Ash Emissions. The proposed fugitive ash emission
limit allowed no visible emissions from ash handling and transfer
points. Several commenters objected to the proposed level of no visible
emissions. The commenters were concerned that even where the best ash
management practices such as wetting the ash or enclosing transfer
systems, there may be short periods of time when visible emissions are
observed, such as during maintenance. The proposal was based on about
16 hours of method 22 visible emissions data for ash handling practices
at two MWC plants and observations (not using method 22) at two
additional MWC plants. Since proposal, the EPA has reviewed visible
emission data from other industries that use similar transfer systems.
Based on comments received and the review of additional data, the final
fugitive ash emission limit was revised to limit visible emissions to
no more than 5 percent of the time.
As part of the final fugitive ash emission requirements, an
exemption has been provided during maintenance and repair activities,
because these necessary activities may require opening of an enclosure
that could generate short-term visible emissions.
3. Good Combustion Practices
The proposed standards included CO limits for nine categories of
combustor technologies, including, among others, RDF stoker combustors
and coal/RDF mixed fuel-fired combustors. Commenters requested
clarification on which CO limit applies to a stoker unit that is
designed to combust coal and RDF but only combusts RDF. Under the final
standards, a spreader stoker unit burning RDF only or cofiring RDF with
coal would be subject to the proposed RDF stoker CO limit. To clarify
this
[[Page 65397]]
requirement, the final CO requirements include an additional category
of combustor technology referred to as ``spreader stoker coal/RDF mixed
fuel-fired combustors,'' which are assigned the same CO limit and
averaging time as RDF stoker combustors (150 ppmv, 24-hour averaging
time). The final standards further clarify that the category of
combustors referred to in the proposed standards as coal/RDF mixed
fuel-fired combustors only includes pulverized coal/RDF mixed fuel
streams, and the CO limit and averaging time remains the same as
proposed (150 ppmv, 4-hour averaging time).
4. Operator Training and Certification
The proposed standards required full ASME certification of chief
facility operators and shift supervisors within 6 months of startup of
an affected MWC. Various commenters including ASME pointed out that the
proposed standards did not include sufficient time for ASME to conduct
full certification exams for all MWC operators. After considering these
comments, the EPA revised the operator training requirements to allow
additional time for ASME (or State) certification exams. In the final
standards, chief facility operators and shift supervisors at new MWC
plants must obtain ASME or State-approved provisional certification
within 1 year after promulgation or 6 months after startup, whichever
is later. In addition, by this same date (1 year after promulgation or
6 months after startup, whichever is later), the same personnel must be
either fully certified or scheduled with ASME or the State to take a
full certification exam (instead of actually obtaining full
certification within 1 year, as proposed).
5. Air Curtain Incinerators
No changes were made to the proposed standards for air curtain
incinerators. As discussed above in section IV.B.1, the final standards
do not cover combustion of clean wood; therefore, air curtain
incinerators combusting only clean wood are not covered by the
standards.
6. Siting Analysis/Materials Separation Plan
Various commenters said the proposed siting analysis was not
consistent with section 129 of the Clean Air Act. Commenters also
argued that the proposed siting requirements were either too stringent
or not stringent enough. The siting analysis in the final rule has been
reworded to allow for a consideration of alternatives, on a sitespecific
basis, to minimize to the maximum extent practicable potential
risks to the public health or the environment. These changes ensure
consistency with section 129(a)(3) of the Clean Air Act.
7. Compliance and Performance Testing
Both the proposed and final standards require all plants to perform
annual performance tests for dioxin/furan emissions. However, a
provision for less frequent dioxin/furan testing has been added to the
final rule to encourage MWC plants to achieve emission levels
significantly lower than 13 ng/dscm. By achieving low dioxin/furan
emissions, they would qualify for less frequent testing and thereby
reduce their testing costs. If all MWC units at an MWC plant achieve 7
ng/dscm dioxins/furans or less during performance testing for 2
consecutive years of operation, the plant can elect to conduct dioxin/
furan testing on one unit per year. The plant must test units in
sequence (e.g., a 3-unit plant would test unit 1 (year 1), unit 2 (year
2), unit 3 (year 3), unit 1 (year 4), etc.). If an annual performance
test conducted on any unit indicates total dioxin/furan emissions are
greater than 7 ng/dscm, the plant must revert to testing all units
annually beginning the following year until the 2-year compliance
record is reestablished.
For small plants, two options are provided. The one-unit incentive
schedule discussed above is provided for dioxin/furan testing. An
alternative 3-year testing option is also provided for small plants.
The alternative 3-year testing option allows small plants to conduct
performance tests for dioxins/furans, as well as PM, HCl, Cd, Pb, and
Hg only once every 3 years if the plant demonstrates compliance with
all pollutant emission limits for 3 consecutive years and continues to
demonstrate compliance every third year. The owner or operator of a
small plant may choose either option for performance testing.
8. Reporting and Recordkeeping Requirements
Reporting requirements have been changed from quarterly as proposed
to annual (semiannual if any emission limits or operating parameters
are violated) to reduce the burden on affected plants. In recognition
of the cost associated with reporting requirements, the EPA
reconsidered the effectiveness of quarterly versus annual reporting for
the purpose of determining compliance. After careful reconsideration,
the EPA has concluded that annual reporting will provide adequate
information for most plants. [The EPA notes, however, that once an MWC
is required to obtain a Title V Operating Permit, the Title V reporting
requirements given in Section 504(a) of the Act will supersede the
annual reporting requirements presented above. Section 504(a) requires
permittees to submit monitoring reports to the permitting authority no
less often than every six months. See 42 U.S.C. 7661c(a).]
C. Impacts of the Standards
The final standards can be achieved by utilizing any technology.
The basis for the MACT-based limits at both proposal and promulgation
remain the combination of GCP/SD/FF and carbon injection for new large
and small plants, and the additional use of SNCR at large plants.
Because the technology basis for the final standards is the same as at
proposal, the impacts analysis presented at proposal has not been
revised. Table 2 provides a brief summary of the air and cost impacts
of the standards. The summary in table 2 provides impacts estimates
relative to two baseline scenarios: a pre-1989 baseline (typical
control prior to the 1991 subpart Ea standards) and a 1991 baseline
(typical control under the 1991 subpart Ea standards). Refer to the
preamble to the proposed standards (59 FR 48198) for a detailed summary
of these air and control cost impacts, as well as a discussion of the
water, solid waste, energy, and economic impacts of the rule. The
national impacts estimates provided in table 2 and discussed in the
proposal preamble represent the EPA's estimate of the worst case of
impacts that would result from implementation of the standards. Recent
data suggest a reduction in the construction of new MWC's. This would
reduce the cost of the standards.
[[Page 65398]]
Table 2.--Impacts of the Current Subpart Ea and Promulgated Subpart Eb Standards
Increment of
promulgated
Parameter standards over 1991 Standards Total <SUP>b
the 1991 <SUP>a
standards
New MWC's subject to Standards in the Fifth Year After
Promulgation:
Combustion capacity (10<SUP>6 Mg/yr)............................. 0.8 16.8 17.6
Number of MWC plants........................................ 24 48 72
Cost (1990 Dollars):
Capital cost ($10<SUP>6)......................................... 156 613 769
Annualized cost ($10<SUP>6/yr)................................... 43 157 200
Average cost increase ($/Mg MSW combusted).................. 1.95 11.55 13.50
Annual Emissions Reduction (Mg/yr):
SO2......................................................... 3,000 35,000 38,000
Hcl......................................................... 4,000 46,000 50,000
PM.......................................................... 800 5,700 6,500
Cd.......................................................... 1 9 10
Pb.......................................................... 17 140 157
Hg.......................................................... 18 9 27
No<INF>x......................................................... 200 10,300 10,500
Total dioxins/furans (kg/yr)................................ 1 28 29
<SUP>a The impacts are based on a pre-1989 baseline (i.e., a baseline prior to the effective date of the subpart Ea
standards.
<SUP>b The total impacts are calculated by adding the incremental impacts of the promulgated standards (subpart Eb)
to the impacts of the 1991 standards (subpart Ea). These impacts would be equivalent to the total impacts of
the promulgated standards over a pre-1989 baseline.
A number of comments were received on the possible effects on EPA's
costing analysis following the recent Supreme Court decision that
``flow control'' is unconstitutional. The EPA considered the effect of
flow control on the financing of new MWC's. In summary, the EPA finds
that if tipping fees are raised to cover the increased costs of these
regulations, then the lack of ``flow control'' requirements will likely
result in fewer MWC's being constructed and a shift of wastes to other
disposal options. The impacts of the flow control decision is likely to
be very place-specific depending on the relative tipping fees of MWC's
and other disposal options, transportation costs, and institutional
factors.
V. Guidelines for Existing Sources (1995)--Summary of the Guidelines,
Impacts of the Guidelines, and Significant Issues and Changes to the
Proposed Guidelines
This section presents a summary of the final guidelines, including
identification of the source category and pollutants being regulated,
and presentation of the final emission limits and their associated
performance testing, monitoring, recordkeeping, and reporting
requirements and compliance schedules. This section also provides a
discussion of the most significant issues and changes to the proposed
guidelines. Also mentioned are the impacts of the final guidelines.
The EPA strongly believes (based on emissions data from MWC's which
incorporate the necessary control technology) that the air pollution
control technology to be retrofitted to existing MWC's to meet the
emission guidelines will reduce actual emissions to levels
significantly below the limits established by the emission guidelines.
There remains, however, some uncertainty as to the actual performance
level that will be achieved on a continuous basis by the control
technology when installed at large MWC plants where ESP-based scrubber
systems are used. Therefore, the dioxin/furan emission limits included
in the emission guidelines for some types of MWC's, while still
significantly below the MACT floor, are slightly less stringent than
those included in the proposal.
The EPA will track the implementation of the guidelines and annual
performance test results in order to monitor the level of emissions
including dioxin/furan control actually achieved by the guidelines.
Additionally, the EPA may conduct supplemental dioxin/furan tests. The
EPA will also meet with MWC owners and operators as needed to review
the performance of the air pollution control technology and the
effectiveness of maintenance and operational practices in order to
provide information that will lead to optimal performance of emission
control technology, and will work with MWC owners and operators to
assure a continued high level of public safety.
A. Summary of the Guidelines
The final guidelines require States to develop emission regulations
limiting air emissions from each existing MWC unit located at a MWC
plant that has an aggregate plant capacity to combust more than 35 Mg/
day of MSW, for which construction commenced on or before September 20,
1994.
The aggregate design capacity of all existing MWC's at an MWC plant
shall be considered in determining: (1) Whether a plant is subject to
the guidelines; and (2) what control levels are applicable. The
capacity of new MWC's (i.e., those that commenced construction after
September 20, 1994 or that commenced modification or reconstruction
after June 19, 1996 that are located at the MWC plant are not
considered in determining applicability of the guidelines but would be
considered in determining the applicability of subpart Eb (standards
for new sources). Only MWC units constructed before September 20, 1994
are considered for determining the applicability of the guidelines.
Modification of an existing MWC (or funds spent) to comply with the
emission guidelines would not be considered in determining if an
existing MWC unit was subject to the standards for new MWC's (subpart
Ea or Eb).
Municipal waste combustion plants with a federally enforceable
permit to combust less than 10 Mg/day of MSW are exempt from the
requirements of the guidelines as long as they submit a notification of
exemption and keep daily records of the weight of MSW combusted.
Cofired combustors (i.e., that combust less than 30 percent MSW)
located at a plant with an aggregate plant capacity greater than 35 Mg/
day are exempt from the requirements of the guidelines as
[[Page 65399]]
long as they submit a notification of exemption and keep records of the
weight of MSW combusted on a calendar quarter basis.
The definitions of MWC and MSW have been revised but are the same
for the guidelines as for the standards, and are discussed in the
summary of the standards in section IV.A of this notice.
A summary of the final guidelines is presented in table 3.
Table 3. Summary of Guidelines for Existing MWC's (Subpart Cb) <SUP>a
[* indicates a significant change since proposal and the change is
discussed in this preamble]
Applicability
The final guidelines apply to existing
MWC's located at plants with
capacities to combust greater than 35
Mg/day of residential, commercial, and/
or institutional discards. Industrial
manufacturing discards are not covered
by the guidelines. Any medical,
industrial manufacturing, municipal,
or other type of waste combustor plant
with capacity to combust greater than
35 Mg/day of MSW and with a federally
enforceable permit to combust less
than 10 Mg/day of MSW is not covered.*
Plant Size (MSW combustion capacity) Requirement
<35 Mg/day*............................ Not covered by guidelines.
> 35 Mg/day but <gr-thn-eq>225 Mg/day Subject to provisions listed
(referred to as small MWC plants). below.
> 225 Mg/day (referred to as large MWC Subject to provisions listed
plants). below.
Good Combustion Practices
<bullet> Applies to large and small MWC plants.
<bullet> A site-specific operator training manual is required to be
developed and made available for MWC personnel.
<bullet> The EPA or a State MWC operator training course would be
required to be completed by the MWC chief facility operator, shift
supervisors, and control room operators.
<bullet> The ASME (or State-equivalent) provisional and full operator
certification must be obtained by the MWC chief facility operator
(mandatory), shift supervisors (mandatory), and control room operators
(optional).*
<bullet> The MWC load level is required to be measured and not to exceed
110 percent of the maximum load level measured during the most recent
dioxin/furan performance test.
<bullet> The maximum PM control device inlet flue gas temperature is
required to be measured and not to exceed the temperature 17 deg.C
above the maximum temperature measured during the most recent dioxin/
furan performance test.
<bullet> The CO level is required to be measured using a CEMS, and the
concentration in the flue gas is required not to exceed the following:
Averaging
MWC type CO level time
(hours)
Modular starved-air and excess-air. 50 ppmv............... 4
Mass burn waterwall and refractory. 100 ppmv.............. 4
Mass burn rotary refractory........ 100 ppmv.............. 24
Fluidized-bed combustion........... 100 ppmv.............. 4
Pulverized coal/RDF mixed fuel- 150 ppmv*............. 4
fired.
Spreader stoker coal/RDF mixed fuel- 200 ppmv*............. 24
fired.
RDF stoker......................... 200 ppmv.............. 24
Mass burn rotary waterwall......... 250 ppmv.............. 24
MWC Organic Emissions (measured as total mass dioxins/furans):
<bullet> Dioxins/furans (performance test by EPA Reference Method 23)
Large MWC plants
MWC units utilizing an ESP-based 60 ng/dscm total mass
air pollution control system. (mandatory) or 15 ng/dscm
total mass (optional to
qualify for less frequent
testing).* <SUP>c
MWC units utilizing a nonESP-based 30 ng/dscm total mass
air pollution control system. (mandatory) or 15 ng/dscm
total mass (optional to
qualify for less frequent
testing).* <SUP>c
Small MWC plants..................... 125 ng/dscm total mass
(mandatory) or 30 ng/dscm
total mass (optional to
qualify for less frequent
testing).* <SUP>c
<bullet> Basis for dioxin/furan limits
Large MWC plants..................... GCP and SD/ESP or GCP and SD/
FF, as specified above.
Small MWC plants..................... GCP and DSI/ESP.
MWC Metal Emissions:
<bullet> PM (performance test by EPA Reference Method 5)
Large MWC plants..................... 27 mg/dscm (0.012 gr/dscf).
Small MWC plants..................... 70 mg/dscm (0.030 gr/dscf).*
<bullet> Opacity (performance test by EPA Reference Method 9)
Large and small MWC plants........... 10 percent (6-minute average)
<bullet> Cd (performance test by EPA Reference Method 29)
Large MWC plants..................... 0.040 mg/dscm (18 gr/million
dscf).
Small MWC plants..................... 0.10 mg/dscm (44 gr/million
dscf).
<bullet> Pb (performance test by EPA Reference Method 29)
Large MWC plants..................... 0.49 mg/dscm (200 gr/million
dscf).*
Small MWC plants..................... 1.6 mg/dscm (700 gr/million
dscf).
<bullet> Hg (performance test by EPA Reference Method 29)
Large and small MWC plants........... 0.080 mg/dscm (35 gr/million
dscf) or 85-percent reduction
in Hg emissions.
<bullet> Basis for PM, opacity, Cd, Pb, and Hg limits
Large MWC plants..................... GCP and SD/ESP/CI or GCP and SD/
FF/CI
[[Page 65400]]
Small MWC plants..................... GCP and DSI/ESP/CI.
MWC Acid Gas Emissions:
<bullet> SO2 (performance test by CEMS)
Large MWC plants..................... 31 ppmv or 75-percent reduction
in SO2 emissions.*
Small MWC plants..................... 80 ppmv or 50-percent reduction
in SO2 emissions.
<bullet> HCl (performance test by EPA Reference Method 26)
Large MWC plants..................... 31 ppmv or 95-percent reduction
in HCl emissions.*
Small MWC plants..................... 250 ppmv or 50-percent
reduction in HCl emissions.
<bullet> Basis for SO2 and HCl limits
Large and small MWC plants........... See basis for MWC metals.
Nitrogen Oxides Emissions
<bullet> NOX(performance test by CEMS)
Large MWC plants:
Mass burn waterwall................ 200 ppmv<SUP>b.
Mass burn rotary waterwall......... 250 ppmv<SUP>b.
Refuse-derived fuel combustor...... 250 ppmv<SUP>b.
Fluidized bed combustor.............. 240 ppmv<SUP>b.
Mass burn refractory................. No NOXcontrol<SUP>b requirement
Other................................ 200 ppmv<SUP>b.
Small MWC plants..................... No NOXcontrol requirement.
<bullet> Basis for NOXlimits
Large MWC plants..................... SNCR.
Refractory MWC plants................ No NOXcontrol requirement
Small MWC plants..................... No NOXcontrol requirement.
Fugitive Ash Emissions:
<bullet> Fugitive Emissions
(performance test by EPA Reference
Method 22)
Large and small plants............... Visible emissions 5 percent of
the time from ash transfer
systems except for maintenance
and repair activities.*
<bullet> Basis for fugitive emission Wet ash handling or enclosed
limit ash handling.
Performance Testing and Monitoring
Requirements:
<bullet> Reporting frequency Annual (semiannual if
violation)*.
<bullet> Load, flue gas temperature Continuous monitoring, 4-hour
block arithmetic average
<bullet> CO CEMS, 4-hour block or 24-hour
daily arithmetic average, as
applicable
<bullet> Dioxins/furans, PM, Cd, Pb,
HCl, and Hg
Large MWC plants..................... Annual stack test.*
Small MWC plants..................... Annual or third year stack
test.
<bullet> Opacity COMS (6-minute average) and
annual stack test.
<bullet> SO2 CEMS, 24-hour daily geometric
mean.
<bullet> NOX(large MWC plants only) CEMS, 24-hour daily arithmetic
average.
<bullet> Fugitive ash emissions Annual test.*
Compliance Schedule:
<bullet> Large MWC plants
State plans are required to include one of the following three
retrofit schedules for compliance with regulatory requirements: (1)
Full compliance or closure within 1 year following EPA approval of
the State plan; (2) full compliance in 1 to 3 years following
issuance of a revised construction or operation permit if a permit
modification is required or 1 to 3 years following EPA approval of
the State plan if a permit modification is not required, provided the
State plan includes measurable and enforceable incremental steps of
progress toward compliance; or (3) closure in 1 to 3 years following
approval of the State plan, provided the State plan includes a
closure agreement. If a State plan allows the second or third
scheduling options (i.e., more than 1 year), the State plan submitted
to EPA must contain post-1990 test data for dioxins/furans for all
MWC units at large plants under the extended schedule. (See Sec.
60.21(h) of subpart B of 40 CFR 60 for additional information
relating to measurable and enforceable incremental steps of progress
toward compliance).
<bullet> Small MWC plants
State plans must require full
compliance or closure with
regulatory requirements in 3 years
or less following issuance of a
revised construction or operation
permit if a permit modification is
required, or within 3 years
following EPA approval of the State
plan if a permit modification is not
required.
<bullet> State plans are required to specify that all MWC's at large MWC
plants for which construction was commenced after June 26, 1987 comply
with the guidelines for Hg and dioxins/furans within 1 year following
issuance of a revised construction or operation permit if a permit
modification is required, or within 1 year following EPA approval of
the State plan, whichever is later.
<bullet> State plans are required to
specify that owners or operators of
MWC's comply with the operator
training and certification
requirements by 6 months after startup
or 1 year after State plan approval by
the EPA, whichever is later, for large
plants and by 6 months after startup
or 18 months after State plan approval
by the EPA, whichever is later, for
small plants.
*=significant change since proposal, and the change is discussed in this
preamble.
<SUP>a All concentration levels in the table are converted to 7 percent O<INF>2,
dry basis.
<SUP>b State plans may allow NOXemissions averaging between existing MWC
units at a large MWC plant. The daily weighted average NOXemissions
concentration from the MWC units included in the emissions averaging
plan must comply with the following 24-hour limits: 180 ppmv for mass
burn waterwall combustors; 220 ppmv for mass burn rotary waterwall
combustors; 230 ppmv for refuse-derived fuel combustors; 220 ppmv for
fluidized bed combustors; and 180 ppmv for other combustor types
(excluding mass burn refractory combustors). Refer to the regulatory
text of the emission guidelines for additional requirements. State
plans may also establish a program to allow emissions trading between
non-contiguous MWC plants. Such a program shall meet the requirements
of the Open Market Trading Rule of Ozone Smog Precursors, proposed
August 3, 1995 (60 FR 39668) as finally promulgated.
<SUP>c Although not part of the dioxin/furan limit, the dioxin/furan total
mass limits of 30 ng/dscm, 60 ng/dscm, and 125 ng/dscm are equal to
about 0.3 to 0.8 ng/dscm TEQ, 0.7 to 1.4 ng/dscm TEQ, and 1.7 to 2.9
ng/dscm TEQ, respectively. The optional reduced testing limits of 15
ng/dscm and 30 ng/dscm total mass are equal to about 0.1 to 0.3 ng/
dscm TEQ and 0.3 to 0.8 ng/dscm TEQ, respectively.
[[Page 65401]]
B. Significant Issues and Changes to the Proposed Guidelines
The most significant changes to the proposed guidelines are
discussed below. Rationales for these changes as well as other changes
not discussed below are provided in the promulgation BID (EPA-453/R-95-
0136). Issues not discussed below include additional changes to GCP
requirements, monitoring requirements, recordkeeping and reporting
requirements, and compliance schedules.
Designated Facilities
Under the final guidelines, any medical, municipal, industrial
manufacturing, or other type of waste combustion plant capable of
combusting greater than 35 Mg/day MSW but actually combusting less than
10 Mg/day of MSW is not a designated facility, as long as the plant
submits an initial report and keeps certain records. This exemption was
not included in the proposed guidelines. This exemption is identical to
the exemption in the standards for new sources. Section IV.B.1 provides
further discussion of the exemption.
Under the final guidelines, a cofired combustor is defined as a
unit combusting a fuel feed stream 30 percent or less MSW, as measured
on a calendar quarterly basis. At proposal, determination of status as
a cofired combustor was measured on a daily basis. This change is
identical to the change made in the standards. Refer to section IV.B.1
for further discussion on the change.
The initial reporting requirement in the proposed guidelines for
MWC plants with combustion capacity greater than 25 Mg/day but less
than or equal to 35 Mg/day is not included in the final guidelines.
Both the proposed and final guidelines exempt plants with capacity less
than 35 Mg/day. Also, an exemption for combustion of clean wood or
clean wood products is included in the final guidelines. This exemption
is identical to the exemption in the standards. Refer to section IV.B.1
for discussion of EPA's rationale for this exemption.
Emission Limits for MWC Metals, Acid Gases, Organics, and Nitrogen
Oxides, and Ash Fugitive Emissions
For existing MWC's, the MACT floor levels and the emission limits
for several pollutants have been revised since proposal. See the
proposal preamble (59 FR 48228, September 20, 1994), the promulgation
BID (EPA-453/R-95-0136), and docket A-90-45 for additional details on
the MACT floor analysis methodology and the selection of MACT.
Since proposal, the EPA revised the MACT floors for existing plants
based on new permit information received and an updated inventory of
operating MWC plants. This revision resulted in revised MACT floor
levels for various pollutants for small and large MWC plants. The
revised MACT floor pollutant levels for large plants have resulted in
more stringent MACT emission limits for SO2, HCl, and Pb. In
addition, the revised MACT floors and emission limits for NOXfor
large plants include emission levels based on combustor type. Revisions
to the MACT floor that resulted in revisions to the selected MACT level
of control for specific pollutants are discussed below.
While the final emission limits are somewhat different from
proposal, the limits can be achieved using the same control
technologies that were the basis of the proposed emission limits. The
technology bases for large and small plants are summarized in table 3.
a. MWC Acid Gases. Based on the new information and test data
received after proposal and the revised MACT floor analysis, the EPA
revised the MACT limits for SO2 and HCl for the final guidelines
for large plants.
The revised SO2 MACT floor for large plants is 31 ppmv. The
final SO2 emission limit for large plants, which was set at the
MACT floor level of 35 ppmv at proposal, is 31 ppmv because of the
change in the MACT floor at promulgation.
The MACT-based SO2 limit of 80 ppmv for small plants has not
changed from proposal; however, the SO2 MACT floor for small
plants is revised to 98 ppmv. Because the revised floor is more
stringent than the proposal floor (the floor at proposal was 118 ppmv),
the EPA's conclusion that acid gas controls will be needed to achieve
the floor remains the same. In addition, the EPA's conclusion that a
lower emission rate of 80 ppmv is achievable at minimal cost also
remains the same. Therefore, the final SO2 emission limit for
small plants remains at 80 ppmv.
The revised HCl MACT floor for large plants is 31 ppmv. The final
HCl emission limit for large plants, which was set at the MACT floor
level of 35 ppmv at proposal, is 31 ppmv because of the change in the
MACT floor at promulgation.
b. MWC Metals. Based on the new information and test data received
after proposal and the revised MACT floor analysis, the Pb limit for
large plants was revised for the final guidelines. The proposed Pb MACT
emission level for large plants was 0.50 mg/dscm; however, the revised
Pb MACT floor emission level for large plants is 0.49 mg/dscm.
Therefore, the final Pb emission limit for large plants has been
revised to 0.49 mg/dscm.
c. MWC Organics. The dioxin/furan emission limits for large and
small plants were revised since proposal. The MACT floor for dioxins/
furans for MWC's at large plants is 126 ng/dscm total mass. As
documented in the preambles to these proposed guidelines (59 FR 48228,
September 20, 1994) and the promulgated subpart Ca guidelines (56 FR
5514, February 11, 1991), in combination with GCP, SD/ESP systems can
achieve dioxin/furan total mass emissions of 60 ng/dscm and SD/FF
systems can achieve dioxin/furan total mass emissions of 30 ng/dscm.
Therefore, the MACT floor of 126 ng/dscm can be achieved with either
SD/ESP or SD/FF systems.
When determining the final MACT standard (which may be more
stringent than the MACT floor), section 129(a)(2) requires the
Administrator to consider certain factors, including the cost of
achieving the emission reduction. In the Administrator's judgment, it
would be prohibitively expensive and unreasonable to require existing
MWC's with ESP's that can meet a dioxin/furan emission limit of 60 ng/
dscm to retrofit an SD/FF in order to achieve an additional 30 ng/dscm
reduction in emissions. For example, at a typical 1,400 Mg/day MWC
plant already equipped with an SD/ESP, the capital cost to remove the
ESP and retrofit a new FF would be about $14 million. This cost would
be in addition to paying the remaining debt for a relatively new ESP
(about $5 million including interest payments) and would result in a
relatively small increase in control device efficiency.
For the final rule, the Administrator considered several regulatory
options more stringent than the MACT floor; however, because of this
high pollution control device retrofit cost, the Administrator decided
to set separate MACT limits for MWC's with ESP-based control systems
and MWC's with nonESP-based control systems. For MWC's with ESP-based
control systems, the EPA selected a MACT level of 60 ng/dscm total
mass, based on the performance of SD/ESP systems. For MWC's using or
retrofitting nonESP-based control systems, the EPA selected a MACT
level of 30 ng/dscm total mass, based on the performance of SD/FF
systems. The number of MWC plants that will comply by using an SD/ESP
will be limited (only about 10 percent of the MWC plants). The vast
majority of MWC's are expected to use SD/FF systems to comply.
[[Page 65402]]
The MACT floor for dioxins/furans at small MWC plants is 1,500 ng/
dscm total mass. As with large MWC plants, the final emission
guidelines limit for dioxins/furans is more stringent than the MACT
floor. The final guideline limit for dioxins/furans at small MWC plants
is 125 ng/dscm total mass and is based on DSI/ESP technology.
The final MACT limit for Hg is based on use of activated carbon
injection. Activated carbon injection technology used in combination
with DSI/ESP, SD/ESP, or SD/FF technology is expected to result in
supplemental dioxin/furan control, reducing dioxin/furan emissions from
these control systems by more than 50 percent. The final MACT guideline
levels for dioxins/furans for existing units at small and large plants
do not consider supplemental dioxin/furan control from activated carbon
injection because an insufficient amount of emissions data exist to
adequately determine the performance level of activated carbon
injection retrofitted to existing MWC air pollution control systems.
Nonetheless, it is expected that the use of activated carbon injection
will result in additional reduction of dioxins/furans to levels below
the emission limits in the final guidelines.
As with the standards for new MWC's, the final guidelines include a
provision that allows less frequent dioxin/furan testing if a plant is
achieving a significantly lower level of dioxin/furan emissions (15 ng/
dscm for MWC's at large plants and 30 ng/dscm for MWC's at small
plants). This option will encourage optimal performance and minimal
emissions. Refer to section IV.B.7 for a description of the alternative
testing schedule.
Relative to the proposal, the optional TEQ format of the proposed
dioxin/furan emission limits was removed in the final standards, as
explained in section IV.B.2.c. Although not part of the dioxin/furan
limit, the dioxin/furan total mass limits of 30 ng/dscm, 60 ng/dscm,
and 125 ng/dscm are equal to about 0.3 to 0.8 ng/dscm TEQ, 0.7 to 1.4
ng/dscm TEQ, and 1.7 to 2.9 ng/dscm TEQ, respectively.
d. Nitrogen Oxides. After considering data submitted by commenters
regarding requiring SNCR for MWC units at large plants where some could
already achieve the MACT floor level without SNCR, the EPA changed the
proposed NOXemission limit of 180 ppmv for all large plants. The
NOXMACT floor was revised by calculating the MACT floor
separately for each subcategory of combustor type, and the MACT limits
are being promulgated at levels equivalent to the MACT floors for each
combustor type. The final guideline MACT limits are: 200 ppmv for mass
burn waterwall combustors; 250 ppmv for refuse-derived fuel combustors;
250 ppmv for mass burn rotary waterwall combustors; 240 ppmv for
fluidized bed combustors; no limit for mass burn refractory combustors;
and 200 ppmv for other combustors not listed above.
In addition, the EPA has revised the emission guidelines to allow
States to include in their State plans options for averaging of
emissions from units within a large MWC plant, and for trading
emissions between MWC plants. The plant average emission limits for
units being included in an emissions averaging plan within a plant are
approximately 10 percent less than the MACT limits for each combustor
type, as follows: 180 ppmv for mass burn waterwall combustors; 220 ppmv
for mass burn rotary waterwall combustors; 230 ppmv for refuse-derived
fuel combustors; 220 ppmv for fluidized bed combustors; and 180 ppmv
for other combustor types (excluding mass burn rotary refractory
combustors). Emissions trading between units at noncontiguous plants
must be consistent with the requirements of the Open Market Trading
Rule for Ozone Smog Precursors, proposed August 3, 1995 (60 FR 39668),
as finally promulgated. Until the Open Market trading rule is
finalized, it is not possible to reference the rule in the guidelines
text. In the interim, the guideline text indicates NOXemissions
trading must be approved by the Administrator prior to implementation.
After the Open Market Trading Rule is finalized, it is preapproved for
use under the guidelines.
e. Fugitive Ash Emissions. The emission limit for fugitive ash
emissions under the final guidelines is visible emissions no more than
5 percent of the time from ash conveying and transfer systems at MWC's.
An exemption for maintenance and repair activities has been added.
These same changes were made to the standards for new sources. See the
discussion of the standards in section IV.B.2.e for an explanation of
the reasons for these changes.
3. Good Combustion Practices
The final CO guidelines include an additional category of combustor
technology referred to as ``spreader stoker coal/RDF mixed fuel-fired
combustors,'' which is assigned the same CO limit and averaging time as
the RDF stoker combustor category (200 ppmv, 24-hour averaging time).
In the final guidelines, the category of combustors referred to in the
proposal as ``coal/RDF mixed fuel-fired combustors'' was revised to
``pulverized coal/RDF mixed fuel-fired combustors,'' and the CO limit
and averaging time remains the same as proposed (150 ppmv, 4-hour
averaging time). These same changes were made to the standards for new
sources. See the discussion of the standards in section IV.B.3 for an
explanation of the reasons for these changes.
4. Operator Training and Certification
As discussed in section IV.B.4 for the standards for new sources,
the EPA has clarified the provisional certification requirements and
revised the schedule for full certification of chief facility operators
and shift supervisors to allow sufficient time to schedule exams. As
stated in the proposal preamble, a State-approved ASME-equivalent
certification program may be substituted for ASME certification.
For large plants, the final guidelines specify that a State plan
must require chief facility operators and shift supervisors to obtain
ASME provisional certification by 1 year after State plan approval or 6
months after startup, whichever is later. In addition, a State plan
must require that, by the same date, these personnel obtain full
certification or be scheduled with ASME to take the ASME full
certification exam (instead of actually obtaining full certification
within 1 year as proposed).
For small plants, the final guidelines specify that a State plan
must require chief facility operators and shift supervisors to obtain
ASME provisional certification by 18 months after State plan approval
or 6 months after startup, whichever is later. In addition, a State
plan must require that, by the same date, these personnel obtain full
certification or be scheduled with ASME to take the ASME full
certification exam (instead of actually obtaining full certification
within 1 year as proposed).
5. Air Curtain Incinerators
No changes were made to the proposed guidelines for air curtain
incinerators. As discussed in section V.B.1, the final guidelines do
not cover combustion of clean wood; therefore, air curtain incinerators
combusting only clean wood are not covered by the guidelines.
6. Compliance and Performance Testing
Under the final guidelines, State plans must specify that all
plants are required to perform annual performance testing for dioxin/
furan emissions. However, a provision for less frequent testing has
been added to encourage plants to
[[Page 65403]]
optimize performance and achieve emission levels significantly lower
than the dioxin/furan emission limits in the final guidelines. State
plans may require that, to take advantage of this provision, existing
MWC's must meet a dioxin/furan level of 15 ng/dscm (large plants) or 30
ng/dscm (small plants), for 2 consecutive years. Refer to the
discussion on the standards for new MWC's under section IV.B.7 for a
description of this reduced testing schedule.
7. Reporting and Recordkeeping Requirements and Compliance Schedules
Reporting requirements have been changed from quarterly to annual
(semiannual if exceeding the emission limit for any pollutant) to
reduce the economic burden on MWC's. Refer to section IV.B.8 for an
explanation of the reasons for this change.
The EPA revised the proposed compliance schedule for large and
small plants to allow more time for small plants to comply with the
guidelines and to clarify the schedule for plants that select to close
down operation rather than retrofit to comply with the guidelines. The
final compliance schedule is as follows. For large MWC plants, State
plans may allow three alternative compliance schedules: (1) Full
compliance or closure within 1 year following approval of the State
plan; (2) full compliance in 1 to 3 years following issuance of a
revised construction or operation permit if a permit modification is
required or 1 to 3 years following approval of the State plan if a
permit modification is not required, provided the State plan includes
measurable and enforceable incremental steps of progress toward
compliance; or (3) closure in 1 to 3 years following approval of the
State plan, provided the State plan includes a closure agreement. If a
State plan allows the second or third scheduling options (i.e., more
than 1 year), the State plan submitted to EPA must include post-1990
test data for dioxins/furans for all MWC units at large plants under
the schedule. For small MWC plants, State plans must require full
compliance or closure in up to 3 years following issuance of a revised
construction or operation permit if a permit modification is required,
or 3 years following approval of the State plan if a permit
modification is not required.
C. Impacts of the Guidelines
The final guidelines can be achieved by designated facilities that
utilize the same control technologies that were the basis for the
proposed guidelines. The basis for the MACT guidelines selected at both
proposal and promulgation is GCP/SD/ESP(or FF)/SNCR and carbon
injection for large plants and GCP/DSI/ESP and carbon injection for
small plants. Because the technology basis for the final guidelines is
the same as at proposal, the impacts analysis presented at proposal has
not been revised for the promulgated rule. Table 4 provides a brief
summary of the air and cost impacts of the guidelines. The summary in
table 4 provides impacts estimates based on two baseline scenarios: A
pre-1989 baseline (control level prior to the 1991 subpart Ca
guidelines) and a 1991 baseline (control level after the 1991 subpart
Ca guidelines.) Refer to the preamble to the proposed guidelines (59 FR
48228) for a detailed summary of these air and control cost impacts, as
well as a discussion of the water, solid waste, energy, and economic
impacts of the guidelines.
Table 4.--Impacts of the 1991 Subpart Ca and Promulgated Subpart Cb Guidelines
Increment of
promulgated 1995
1991 subpart Ca Promulgated 1995 subpart Cb
Parameter guidelines <SUP>a subpart Cb guidelines over
guidelines <SUP>a the 1991 subpart
Ca guidelines <SUP>b
Characteristics of Existing MWC's:
Combustion capacity (10 \6\ Mg/yr)................... 35.9 39.0 3.1
Number of MWC plants................................. 158 179 21
Cost (1990 Dollars):
Capital cost ($10 \6\)............................... 888 2,100 1,212
Annualized cost ($10 \6\/yr)......................... 168 445 277
Average cost increase ($/Mg MSW combusted)........... 6.40 13.60 7.20
Annual Emissions Reduction (Mg/yr):
SO2.................................................. 25,000 43,000 18,000
HCl.................................................. 36,000 56,000 20,000
PM................................................... 1,100 3,100 2,000
Cd................................................... 2 5 3
Pb................................................... 30 83 53
Hg................................................... 11 47 36
NO<INF>X.................................................. 0 19,000 19,000
Total dioxins/furans (kg/yr)..................... 117 157 40
<SUP>a The impacts are based on a pre-1989 baseline (i.e., a baseline prior to the effective date of the subpart Ca
guidelines).
<SUP>b The impacts are calculated by subtracting the impacts of the 1991 subpart Ca guidelines from the impacts of
the promulgated 1995 subpart Cb guidelines (based on a pre-1989 baseline).
The national impacts estimates provided in table 4 and discussed in
the proposal preamble represent EPA's estimate of the upper limit of
impacts that would result from implementation of the guidelines. To the
extent that any existing MWC's close rather than comply with the
guidelines or switch to other disposal options that may cost less, the
national costs will be lower and air emissions will be less.
A number of comments were received on the possible effects on EPA's
costing analysis following the recent Supreme Court decision that
``flow control'' is unconstitutional. The EPA considered the effect of
flow control on the financing of existing MWC's. In summary, the EPA
finds that if MWC's raise tipping fees to cover the increased costs of
these regulations, then the lack of ``flow control'' will likely result
in a shift of some wastes to other disposal options. The combined
impacts of no flow control and increased tipping fees on individual
MWC's and municipalities are likely to be very
[[Page 65404]]
place-specific depending on the relative tipping fees of MWC's and
other disposal options, transportation costs, and institutional
factors. If tipping fees are not raised to offset emission control
costs, then operators of MWC's will have to finance the costs of the
regulations out of current revenues.
The EPA has identified several ways that State and local
governments can guarantee a continued source of MSW for the MWC's and
provide funds from the general revenue to support the operation of MWC
facilities, accomplishing some of the outcomes that flow control can
produce, including: (1) Government provision of collection services;
(2) contractor provision of collection services under government
contract; (3) franchising collection and hauling to designated
facilities; (4) subsidizing facilities from the general revenues; and
(5) supporting integrated solid waste management programs from the
general revenue.
VI. Administrative Requirements
This section addresses the following administrative requirements:
Docket, Paperwork Reduction Act, Executive Orders 12866 and 12875,
Unfunded Mandates Act, Regulatory Flexibility Act, and Clean Air Act
Procedural Requirements.
A. Docket
The docket is an organized and complete file of all the information
considered in the development of this rulemaking. The principal
purposes of the docket are: (1) To allow interested parties to identify
and locate documents so that they can effectively participate in the
rulemaking process; and (2) to serve as the record in case of judicial
review, except for interagency review material. 42 U.S.C.
Sec. 7607(d)(7)(A). The docket number for this rulemaking is A-90-45.
Docket No. A-89-08 also includes background information for this
rulemaking that supported the proposal and promulgation of the subpart
Ea standards and subpart Ca guidelines.
B. Paperwork Reduction Act
The information collection requirements in this rule have been
submitted for approval to the Office of Management and Budget (OMB)
under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. An
Information Collection Request (ICR) document has been prepared by EPA
(ICR No. 1506.5) and a copy may be obtained from Sandy Farmer, OPPE
Regulatory Information Division; U.S. Environmental Protection Agency
(2136); 401 M St., S.W.; Washington, DC 20460 or by calling (202) 260-
2740. This ICR document is also available on the EPA's TTN Clean Air
Act Amendments electronic bulletin board. See the SUPPLEMENTARY
INFORMATION section of this preamble for information on accessing EPA's
TTN electronic bulletin board.
The information required to be collected by this rule is necessary
to identify the regulated entities who are subject to the rule and to
ensure their compliance with the rule. The recordkeeping and reporting
requirements are mandatory and are being established under authority of
Section 114 of the Act. All information submitted as part of a report
to the Agency for which a claim of confidentiality is made will be
safeguarded according to the Agency policies set forth in Title 40,
Chapter 1, part 2, subpart B--Confidentiality of Business Information
(see 40 CFR 2; 41 FR 36902, September 1, 1976, amended by 43 FR 39999,
September 28, 1978; 43 FR 42251, September 28, 1978; 44 FR 17674, March
23, 1979).
The annual reporting and recordkeeping burden presented in this ICR
document reflects only part of the burden imposed by this rule. The
rest of the burden was presented to and approved by the OMB in an ICR
document in 1991 for the subpart Ea NSPS promulgated in February 1991.
The ICR document that accompanied the subpart Ea rulemaking summarized
the reporting and recordkeeping requirements that MWC owners and
operators of large MWC units are required to follow to demonstrate
compliance with the 1991 NSPS. As explained elsewhere in this document,
the Clean Air Act Amendments were passed by Congress in 1990, and they
included section 129 that directs the Administrator to extend the NSPS
to small MWC plants, as well as to include emission limits for
additional pollutants and siting requirements. This ICR document for
subpart Eb presents this additional burden imposed by section 129 of
the Act, by summarizing the total annual burden on small plants (i.e.,
for the reporting and recordkeeping requirements associated with all
pollutant emission limits and siting) and the additional annual burden
on large MWC plants (i.e., only for requirements associated with Cd,
Pb, Hg, and fugitive ash emission limits and siting).
The total annual reporting and recordkeeping burden summarized in
this ICR document for this collection averaged over the first 3 years
of NSPS application to new MWC's is estimated to be about 69,700 person
hours per year. This would be the estimated annual burden for 64
respondents (i.e., MWC units). This is a worst-case burden estimate, as
discussed under section IV.C. If fewer MWC units are constructed than
have been projected, then the burden will be less than reported here.
The average burden per respondent is about 1,100 person hours per year.
The rule requires an initial one-time notification from each new MWC
regarding all pollutant emission levels and siting and subsequent
annual compliance reports regarding all pollutant emission levels.
Additionally, if any of the pollutant emission limits are exceeded,
respondents would be required to submit semi-annual reports. The rule
includes continuous monitoring requirements for SO2, opacity, CO,
CO<INF>2, O<INF>2 and annual stack testing requirements for PM,
dioxins/furans, opacity, HCl, Cd, Pb, Hg, and fugitive ash. Efforts
were made to reduce the burden on small plants by allowing them to test
emissions once every 3 years instead of annually if they demonstrate
that they consistently meet the emissions requirements. This burden
estimate includes the time needed to review instructions; develop,
acquire, install, and utilize technology and systems for the purposes
of collecting, validating, and verifyi ![[logo] US EPA](http://www.epa.gov/epafiles/images/logo_epaseal.gif){kind=logo}