[Federal Register Volume 76, Number 33 (Thursday, February 17, 2011)]
[Proposed Rules]
[Pages 9410-9447]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-2866]
[[Page 9409]]
Vol. 76
Thursday,
No. 33
February 17, 2011
Part II
Environmental Protection Agency
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40 CFR Part 63
National Emission Standards for Hazardous Air Pollutants: Primary Lead
Smelting; Proposed Rule
Federal Register / Vol. 76, No. 33 / Thursday, February 17, 2011 /
Proposed Rules
[[Page 9410]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 63
[EPA-HQ-OAR-2004-0305; FRL-9263-2]
RIN 2060-AQ43
National Emission Standards for Hazardous Air Pollutants: Primary
Lead Smelting
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: EPA is proposing amendments to the national emission standards
for hazardous air pollutants (NESHAP) for Primary Lead Smelting to
address the results of the residual risk and technology reviews
conducted as required under sections 112(d)(6) and (f)(2) of the Clean
Air Act (CAA). These proposed amendments include revisions to the
emission limits for lead, the addition of a lead concentration in air
standard, and the modification and addition of testing and monitoring
and related notification, recordkeeping, and reporting requirements. We
are also proposing to revise provisions addressing periods of startup,
shutdown, and malfunction to ensure that they are consistent with a
recent court decision. Finally, we are proposing revisions to the
rule's applicability provision to make it consistent with the
definition of the source category and proposing other minor technical
changes to the standard. We are also responding to a petition for
rulemaking filed on the standard with regard to lead as a surrogate and
regulation of volatile organic compounds (VOC) and acid gases.
DATES: Comments must be received on or before April 4, 2011. Under the
Paperwork Reduction Act, comments on the information collection
provisions are best assured of having full effect if the Office of
Management and Budget (OMB) receives a copy of your comments on or
before March 21, 2011.
Public Hearing. If anyone contacts EPA requesting to speak at a
public hearing by February 28, 2011, a public hearing will be held on
March 4, 2011.
ADDRESSES: Submit your comments, identified by Docket ID Number EPA-HQ-
OAR-2004-0305, by one of the following methods:
http://www.regulations.gov: Follow the on-line
instructions for submitting comments.
E-mail: [email protected], Attention Docket ID Number
EPA-HQ-OAR-2004-0305.
Fax: (202) 566-9744, Attention Docket ID Number EPA-HQ-
OAR-2004-0305.
Mail: U.S. Postal Service, send comments to: EPA Docket
Center, EPA West (Air Docket), Attention Docket ID Number EPA-HQ-OAR-
2004-0305, U.S. Environmental Protection Agency, Mailcode: 2822T, 1200
Pennsylvania Ave., NW., Washington, DC 20460. Please include a total of
two copies. In addition, please mail a copy of your comments on the
information collection provisions to the Office of Information and
Regulatory Affairs, Office of Management and Budget (OMB), Attn: Desk
Officer for EPA, 725 17th Street, NW., Washington, DC 20503.
Hand Delivery: U.S. Environmental Protection Agency, EPA
West (Air Docket), Room 3334, 1301 Constitution Ave., NW., Washington,
DC 20004, Attention Docket ID Number EPA-HQ-OAR-2004-0305. Such
deliveries are only accepted during the Docket's normal hours of
operation, and special arrangements should be made for deliveries of
boxed information.
Instructions. Direct your comments to Docket ID Number EPA-HQ-OAR-
2004-0305. EPA's policy is that all comments received will be included
in the public docket without change and may be made available on-line
at http://www.regulations.gov, including any personal information
provided, unless the comment includes information claimed to be
confidential business information (CBI) or other information whose
disclosure is restricted by statute. Do not submit information that you
consider to be CBI or otherwise protected through http://www.regulations.gov or e-mail. The http://www.regulations.gov Web site
is an ``anonymous access'' system, which means EPA will not know your
identity or contact information unless you provide it in the body of
your comment. If you send an e-mail comment directly to EPA without
going through http://www.regulations.gov, your e-mail address will be
automatically captured and included as part of the comment that is
placed in the public docket and made available on the Internet. If you
submit an electronic comment, EPA recommends that you include your name
and other contact information in the body of your comment and with any
disk or CD-ROM you submit. If EPA cannot read your comment due to
technical difficulties and cannot contact you for clarification, EPA
may not be able to consider your comment. Electronic files should avoid
the use of special characters, any form of encryption, and be free of
any defects or viruses. For additional information about EPA's public
docket, visit the EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.
Docket. The EPA has established a docket for this rulemaking under
Docket ID Number EPA-HQ-OAR-2004-0305. All documents in the docket are
listed in the http://www.regulations.gov index. Although listed in the
index, some information is not publicly available, e.g., CBI or other
information whose disclosure is restricted by statute. Certain other
material, such as copyrighted material, is not placed on the Internet
and will be publicly available only in hard copy. Publicly available
docket materials are available either electronically in http://www.regulations.gov or in hard copy at the EPA Docket Center, EPA West,
Room 3334, 1301 Constitution Ave., NW., Washington, DC. The Public
Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through
Friday, excluding legal holidays. The telephone number for the Public
Reading Room is (202) 566-1744, and the telephone number for the EPA
Docket Center is (202) 566-1742.
Public Hearing. If a public hearing is held, it will begin at 10
a.m. on March 4, 2011 and will be held at EPA's campus in Research
Triangle Park, North Carolina, or at an alternate facility nearby.
Persons interested in presenting oral testimony or inquiring as to
whether a public hearing is to be held should contact Ms. Virginia
Hunt, Office of Air Quality Planning and Standards, Sector Policies and
Programs Division, Metals and Minerals Group (D243-02), U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina
27711; telephone number: (919) 541-0832.
FOR FURTHER INFORMATION CONTACT: For questions about this proposed
action, contact Ms. Sharon Nizich, Sector Policies and Programs
Division (D243-02), Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina
27711, telephone (919) 541-2825; fax number: (919) 541-5450; and e-mail
address: [email protected]. For specific information regarding the
risk modeling methodology, contact Ms. Elaine Manning, Health and
Environmental Impacts Division (C539-02), Office of Air Quality
Planning and Standards, U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina 27711; telephone number: (919) 541-5499;
fax number: (919) 541-0840; and e-mail address: [email protected].
For information about the applicability of
[[Page 9411]]
the NESHAP to a particular entity, contact the appropriate person
listed in Table 1 to this preamble.
SUPPLEMENTARY INFORMATION:
Table 1--List of EPA Contacts For the NESHAP Addressed in This Proposed Action
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NESHAP for: OECA contact \1\ OAQPS contact \2\
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Primary Lead Smelting..................... Maria Malave, (202) 564-7027, Sharon Nizich, (919) 541-2825,
[email protected]. [email protected].
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\1\ EPA's Office of Enforcement and Compliance Assurance.
\2\ EPA's Office of Air Quality Planning and Standards.
I. Preamble Acronyms and Abbreviations
Several acronyms and terms used to describe industrial processes,
data inventories, and risk modeling are included in this preamble.
While this may not be an exhaustive list, to ease the reading of this
preamble and for reference purposes, the following terms and acronyms
are defined here:
ADAF Age-dependent Adjustment Factors
AERMOD Air dispersion model used by the HEM-3 model
AEGL Acute Exposure Guideline Levels
ANPRM Advance Notice of Proposed Rulemaking
BACT Best Available Control Technology
CAA Clean Air Act
CBI Confidential Business Information
CEEL Community Emergency Exposure Levels
CEMS Continuous Emissions Monitoring System
CERMS Continuous Emission Rate Monitoring System
CFR Code of Federal Regulations
EJ Environmental Justice
EPA Environmental Protection Agency
ERPG Emergency Response Planning Guidelines
HAP Hazardous Air Pollutants
HI Hazard Index
HEM-3 Human Exposure Model version 3
HON Hazardous Organic National Emissions Standards for Hazardous Air
Pollutants
HQ Hazard Quotient
IRIS Integrated Risk Information System
Km Kilometer
LAER Lowest Achievable Emission Rate
LOAEL Lowest Observed Adverse Effect Level
MACT Maximum Achievable Control Technology
MACT Code Code within the NEI used to identify processes included in
a source category
MIR Maximum Individual Risk
NAAQS National Ambient Air Quality Standard
NAC/AEGL Committee National Advisory Committee for Acute Exposure
Guideline Levels for Hazardous Substances
NAICS North American Industry Classification System
NAS National Academy of Sciences
NATA National Air Toxics Assessment
NESHAP National Emissions Standards for Hazardous Air Pollutants
NEI National Emissions Inventory
NOAEL No Observed Adverse Effects Level
NRC National Research Council
NTTAA National Technology Transfer and Advancement Act
OAQPS EPA's Office of Air Quality Planning and Standards
OECA EPA's Office of Enforcement and Compliance Assurance
OMB Office of Management and Budget
PB-HAP Hazardous air pollutants known to be persistent and bio-
accumulative in the environment
POM Polycyclic Organic Matter
RACT Reasonably Available Control Technology
RBLC RACT/BACT/LAER Clearinghouse
RFA Regulatory Flexibility Act
RfC Reference Concentration
RfD Reference Dose
RTR Residual Risk and Technology Review
SAB Science Advisory Board
SBA Small Business Administration
SCC Source Classification Codes
SF3 2000 Census of Population and Housing Summary File 3
SIP State Implementation Plan
SOP Standard Operating Procedures
SSM Startup, Shutdown, and Malfunction
TOSHI Target Organ-Specific Hazard Index
TPY Tons Per Year
TRIM Total Risk Integrated Modeling System
TTN Technology Transfer Network
UF Uncertainty Factor
UMRA Unfunded Mandates Reform Act
URE Unit Risk Estimate
VOC Volatile Organic Compounds
VOHAP Volatile Organic Hazardous Air Pollutants
WWW Worldwide Web
Organization of this Document. The following outline is provided to
aid in the location of information in this preamble.
I. Preamble Acronyms and Abbreviations
II. General Information
A. Does this action apply to me?
B. Where can I get a copy of this document and other related
information?
C. What should I consider as I prepare my comments for EPA?
III. Background
A. What is the statutory authority for this action?
B. How did we consider the risk results in making decisions for
this proposal?
C. What other actions are we addressing in this proposal?
IV. Analyses Performed and Background for the Source Category and
MACT Standard
A. How did we estimate risks posed by the source category?
B. How did we perform the technology review?
C. Overview of the source category and MACT standards
V. Analyses Results and Proposed Decisions
A. What data were used in our risk analyses?
B. What are the results of the risk assessments and analyses?
C. What are our proposed decisions on risk acceptability and
ample margin of safety?
D. What are the results and proposed decisions from the
technology review?
E. Variability
F. What other actions are we proposing?
VI. Proposed Action
A. What actions are we proposing as a result of the residual
risk reviews?
B. What actions are we proposing as a result of the technology
reviews?
C. What other actions are we proposing?
D. Compliance Dates
VII. Request for Comments
VIII.Submitting Data Corrections
IX. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review
B. Paperwork Reduction Act
C. Regulatory Flexibility Act
D. Unfunded Mandates Reform Act
E. Executive Order 13132: Federalism
F. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
G. Executive Order 13045: Protection of Children From
Environmental Health Risks and Safety Risks
H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use
I. National Technology Transfer and Advancement Act
J. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations
II. General Information
A. Does this action apply to me?
The regulated industrial source category that is the subject of
this proposal is listed in Table 2 to this preamble. Table 2 is not
intended to be exhaustive, but rather provides a guide for readers
regarding entities likely to be affected by this proposed action for
the source categories listed. This standard, and any changes considered
in this rulemaking, would be directly
[[Page 9412]]
applicable to sources as a Federal program. Thus, Federal, State,
local, and tribal government entities are not affected by this proposed
action. As defined in the source category listing report published by
EPA in 1992, the Primary Lead Smelting source category is defined as
any facility engaged in producing lead metal from ore concentrates;
including, but not limited to, the following smelting processes:
sintering, reduction, preliminary treatment, and refining
operations.\1\ As discussed in section III. (C)(3), to be consistent
with the 1992 listing, EPA is proposing to change the applicability of
the Primary Lead Smelting NESHAP to apply to any facility that produces
lead metal from lead ore concentrates. Although the source category
name in the 1992 listing will remain Primary Lead Smelting (as in 1992
listing) we are proposing to change the title of the rule to refer to
Primary Lead Processing. For clarification purposes, all references to
lead emissions in this preamble means ``lead compounds'' (which is a
HAP) and all reference to lead production means elemental lead (which
is not a HAP) as provided under CAA 112(b)(7)).
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\1\ USEPA. Documentation for Developing the Initial Source
Category List--Final Report, USEPA/OAQPS, EPA-450/3-91-030, July,
1992.
Table 2--Neshap and Industrial Source Categories Affected by This Proposed Action
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Source category NESHAP NAICS code \1\ MACT code \2\
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Primary Lead Smelting...................... Primary Lead Processing............ 331419 0204
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\1\ North American Industry Classification System.
\2\ Maximum Achievable Control Technology.
B. Where can I get a copy of this document and other related
information?
In addition to being available in the docket, an electronic copy of
this proposal will also be available on the World Wide Web (WWW)
through the Technology Transfer Network (TTN). Following signature by
the EPA Administrator, a copy of this proposed action will be posted on
the TTN's policy and guidance page for newly proposed or promulgated
rules at the following address: http://www.epa.gov/ttn/atw/rrisk/rtrpg.html. The TTN provides information and technology exchange in
various areas of air pollution control.
Additional information is available on the residual risk and
technology review (RTR) Web page at http://www.epa.gov/ttn/atw/rrisk/rtrpg.html. This information includes source category descriptions and
detailed emissions and other data that were used as inputs to the risk
assessments.
C. What should I consider as I prepare my comments for EPA?
Submitting CBI. Do not submit information containing CBI to EPA
through http://www.regulations.gov or e-mail. Clearly mark the part or
all of the information that you claim to be CBI. For CBI information on
a disk or CD ROM that you mail to EPA, mark the outside of the disk or
CD ROM as CBI and then identify electronically within the disk or CD
ROM the specific information that is claimed as CBI. In addition to one
complete version of the comment that includes information claimed as
CBI, a copy of the comment that does not contain the information
claimed as CBI must be submitted for inclusion in the public docket. If
you submit a CD ROM or disk that does not contain CBI, mark the outside
of the disk or CD ROM clearly that it does not contain CBI. Information
not marked as CBI will be included in the public docket and EPA's
electronic public docket without prior notice. Information marked as
CBI will not be disclosed except in accordance with procedures set
forth in 40 CFR part 2. Send or deliver information identified as CBI
only to the following address: Roberto Morales, OAQPS Document Control
Officer (C404-02), Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina
27711, Attention Docket ID Number EPA-HQ-OAR-2004-0305.
III. Background
A. What is the statutory authority for this action?
Section 112 of the Clean Air Act (CAA) establishes a two-stage
regulatory process to address emissions of hazardous air pollutants
(HAP) from stationary sources. In the first stage, after EPA has
identified categories of sources emitting one or more of the HAP listed
in section 112(b) of the CAA, section 112(d) of the CAA calls for us to
promulgate NESHAP for those sources. ``Major sources'' are those that
emit or have the potential to emit 10 tons per year (TPY) or more of a
single HAP or 25 TPY or more of any combination of HAP. For major
sources, these technology-based standards must reflect the maximum
degree of emission reductions of HAP achievable (after considering
cost, energy requirements, and non-air quality health and environmental
impacts) and are commonly referred to as maximum achievable control
technology (MACT) standards.
MACT standards must require the maximum degree of emission
reduction through the application of measures, processes, methods,
systems, or techniques, including, but not limited to, measures which
(A) Reduce the volume of or eliminate pollutants through process
changes, substitution of materials or other modifications; (B) enclose
systems or processes to eliminate emissions; (C) capture or treat
pollutants when released from a process, stack, storage, or fugitive
emissions point; (D) are design, equipment, work practice, or
operational standards (including requirements for operator training or
certification); or (E) are a combination of the above. CAA section
112(d)(2)(A)-(E). The MACT standards may take the form of design,
equipment, work practice, or operational standards where EPA first
determines either that, (A) a pollutant cannot be emitted through a
conveyance designed and constructed to emit or capture the pollutants,
or that any requirement for, or use of, such a conveyance would be
inconsistent with law; or (B) the application of measurement
methodology to a particular class of sources is not practicable due to
technological and economic limitations. CAA sections 112(h)(1)-(2).
The MACT ``floor'' is the minimum control level allowed for MACT
standards promulgated under CAA section 112(d)(3) and may not be based
on cost considerations. For new sources, the MACT floor cannot be less
stringent than the emission control that is achieved in practice by the
best-
[[Page 9413]]
controlled similar source. The MACT floors for existing sources can be
less stringent than floors for new sources, but they cannot be less
stringent than the average emissions limitation achieved by the best-
performing 12 percent of existing sources in the category or
subcategory (or the best-performing 5 sources for categories or
subcategories with fewer than 30 sources). In developing MACT
standards, we must also consider control options that are more
stringent than the floor. We may establish standards more stringent
than the floor based on the consideration of the cost of achieving the
emissions reductions, any non-air quality health and environmental
impacts, and energy requirements.
The EPA is then required to review these technology-based standards
and to revise them ``as necessary (taking into account developments in
practices, processes, and control technologies)'' no less frequently
than every 8 years, under CAA section 112(d)(6). In conducting this
review, EPA is not obliged to completely recalculate the prior MACT
determination. NRDC v. EPA, 529 F.3d 1077, 1084 (D.C. Cir., 2008).
The second stage in standard-setting focuses on reducing any
remaining ``residual'' risk according to CAA section 112(f). This
provision requires, first, that EPA prepare a Report to Congress
discussing (among other things) methods of calculating the risks posed
(or potentially posed) by sources after implementation of the MACT
standards, the public health significance of those risks, and the
recommendations regarding legislation of such remaining risk. EPA
prepared and submitted this report (Residual Risk Report to Congress,
EPA-453/R-99-001) in March 1999. Congress did not act in response to
the report, thereby triggering EPA's obligation under CAA section
112(f)(2) to analyze and address residual risk.
Section 112(f)(2) of the CAA requires us to determine for source
categories subject to certain MACT standards, whether the emissions
standards provide an ample margin of safety to protect public health.
If the MACT standards that apply to a source category emitting a HAP
that is ``classified as a known, probable, or possible human carcinogen
do not reduce lifetime excess cancer risks to the individual most
exposed to emissions from a source in the category or subcategory to
less than one-in-one million,'' EPA must promulgate residual risk
standards for the source category (or subcategory) as necessary to
provide an ample margin of safety to protect public health. CAA section
112(f)(2)(A). In doing so, EPA may adopt standards equal to existing
MACT standards if EPA determines that the existing standards are
sufficiently protective. As stated in NRDC v. EPA, 529 F.3d 1077, 1083
(D.C. Dir. 2008), ``If EPA determines that the existing technology-
based standards provide an `ample margin of safety,' then the Agency is
free to readopt those standards during the residual risk rulemaking.''
Section 112(f)(2) of the Clean Air Act further states that EPA must
also adopt more stringent standards, if necessary, to ``prevent taking
into consideration costs, energy, safety, and other relevant factors,
an adverse environmental effect.'' \2\
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\2\ ``Adverse environmental effect'' is defined in CAA section
112(a)(7) as any significant and widespread adverse effect, which
may be reasonably anticipated to wildlife, aquatic life, or natural
resources, including adverse impacts on populations of endangered or
threatened species or significant degradation of environmental
qualities over broad areas.
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When Section 112(f)(2) of the CAA was enacted in 1990, it expressly
preserved our use of the two-step process for developing standards to
address any residual risk and our interpretation of ``ample margin of
safety'' developed in the National Emission Standards for Hazardous Air
Pollutants: Benzene Emissions from Maleic Anhydride Plants,
Ethylbenzene/Styrene Plants, Benzene Storage Vessels, Benzene Equipment
Leaks, and Coke By-Product Recovery Plants (Benzene NESHAP) (54 FR
38044, September 14, 1989). The first step in this process is the
determination of acceptable risk. The second step provides for an ample
margin of safety to protect public health, which is the level at which
the standards are set (unless a more stringent standard is required to
prevent, taking into consideration costs, energy, safety, and other
relevant factors, an adverse environmental effect).
The terms ``individual most exposed,'' ``acceptable level,'' and
``ample margin of safety'' are not specifically defined in the CAA.
However, CAA section 112(f)(2)(B) preserves the interpretation set out
in the Benzene NESHAP, and the Court in NRDC v. EPA, concluded that
EPA's interpretation of subsection 112(f)(2) is a reasonable one. See
NRDC v. EPA, 529 F.3d at 1083 (D.C. Cir. 2008), which says
``[S]ubsection 112(f)(2)(B) expressly incorporates EPA's interpretation
of the Clean Air Act from the Benzene standard, complete with a
citation to the Federal Register.'' See also, A Legislative History of
the Clean Air Act Amendments of 1990, volume 1, p. 877 (Senate debate
on Conference Report). We notified Congress in the Residual Risk Report
to Congress that we intended to use the Benzene NESHAP approach in
making CAA section 112(f) residual risk determinations (EPA-453/R-99-
001, p. ES-11).
In the Benzene NESHAP, we stated as an overall objective:
* * * in protecting public health with an ample margin of
safety, we strive to provide maximum feasible protection against
risks to health from hazardous air pollutants by (1) protecting the
greatest number of persons possible to an individual lifetime risk
level no higher than approximately 1-in-1 million; and (2) limiting
to no higher than approximately 1-in-10 thousand [i.e., 100-in-1
million] the estimated risk that a person living near a facility
would have if he or she were exposed to the maximum pollutant
concentrations for 70 years.
The Agency also stated that, ``The EPA also considers incidence
(the number of persons estimated to suffer cancer or other serious
health effects as a result of exposure to a pollutant) to be an
important measure of the health risk to the exposed population.
Incidence measures the extent of health risks to the exposed population
as a whole, by providing an estimate of the occurrence of cancer or
other serious health effects in the exposed population.'' The Agency
went on to conclude that ``estimated incidence would be weighed along
with other health risk information in judging acceptability.'' As
explained more fully in our Residual Risk Report to Congress, EPA does
not define ``rigid line[s] of acceptability,'' but considers rather
broad objectives to be weighed with a series of other health measures
and factors (EPA-453/R-99-001, p. ES-11). The determination of what
represents an ``acceptable'' risk is based on a judgment of ``what
risks are acceptable in the world in which we live'' (Residual Risk
Report to Congress, p. 178, quoting the Vinyl Chloride decision at 824
F.2d 1165) recognizing that our world is not risk-free.
In the Benzene NESHAP, we stated that ``EPA will generally presume
that if the risk to [the maximum exposed] individual is no higher than
approximately 1-in-10 thousand, that risk level is considered
acceptable.'' 54 FR 38045. We discussed the maximum individual lifetime
cancer risk as being ``the estimated risk that a person living near a
plant would have if he or she were exposed to the maximum pollutant
concentrations for 70 years.'' Id. We explained that this measure of
risk ``is an estimate of the upper bound of risk based on conservative
assumptions, such as continuous exposure for 24 hours per day for 70
years.'' Id. We
[[Page 9414]]
acknowledge that maximum individual lifetime cancer risk ``does not
necessarily reflect the true risk, but displays a conservative risk
level which is an upper-bound that is unlikely to be exceeded.'' Id.
Understanding that there are both benefits and limitations to using
maximum individual lifetime cancer risk as a metric for determining
acceptability, we acknowledged in the 1989 Benzene NESHAP that
``consideration of maximum individual risk * * * must take into account
the strengths and weaknesses of this measure of risk.'' Id.
Consequently, the presumptive risk level of 100-in-1 million (1-in-10
thousand) provides a benchmark for judging the acceptability of maximum
individual lifetime cancer risk, but does not constitute a rigid line
for making that determination.
The Agency also explained in the 1989 Benzene NESHAP the following:
``In establishing a presumption for MIR [maximum individual cancer
risk], rather than a rigid line for acceptability, the Agency intends
to weigh it with a series of other health measures and factors. These
include the overall incidence of cancer or other serious health effects
within the exposed population, the numbers of persons exposed within
each individual lifetime risk range and associated incidence within,
typically, a 50-kilometer (km) exposure radius around facilities, the
science policy assumptions and estimation uncertainties associated with
the risk measures, weight of the scientific evidence for human health
effects, other quantified or unquantified health effects, effects due
to co-location of facilities, and co-emission of pollutants.'' Id.
In some cases, these health measures and factors taken together may
provide a more realistic description of the magnitude of risk in the
exposed population than that provided by maximum individual lifetime
cancer risk alone. As explained in the Benzene NESHAP, ``[e]ven though
the risks judged ``acceptable'' by EPA in the first step of the Vinyl
Chloride inquiry are already low, the second step of the inquiry,
determining an ``ample margin of safety,'' again includes consideration
of all of the health factors, and whether to reduce the risks even
further.'' In the ample margin of safety decision process, the Agency
again considers all of the health risks and other health information
considered in the first step. Beyond that information, additional
factors relating to the appropriate level of control will also be
considered, including costs and economic impacts of controls,
technological feasibility, uncertainties, and any other relevant
factors. Considering all of these factors, the Agency will establish
the standard at a level that provides an ample margin of safety to
protect the public health, as required by CAA section 112(f). 54 FR
38046.
B. How did we consider the risk results in making decisions for this
proposal?
As discussed in section III.A of this preamble, we apply a two-step
process for developing standards to address residual risk. In the first
step, EPA determines if risks are acceptable. This determination
``considers all health information, including risk estimation
uncertainty, and includes a presumptive limit on maximum individual
lifetime [cancer] risk (MIR) \3\ of approximately 1-in-10 thousand
[i.e., 100-in-1 million].'' 54 FR 38045. In the second step of the
process, EPA sets the standard at a level that provides an ample margin
of safety ``in consideration of all health information, including the
number of persons at risk levels higher than approximately 1-in-1
million, as well as other relevant factors, including costs and
economic impacts, technological feasibility, and other factors relevant
to each particular decision.'' Id.
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\3\ Although defined as ``maximum individual risk,'' MIR refers
only to cancer risk. MIR, one metric for assessing cancer risk, is
the estimated risk were an individual exposed to the maximum level
of a pollutant for a lifetime.
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In past residual risk actions, EPA has presented and considered a
number of human health risk metrics associated with emissions from the
category under review, including: the MIR; the numbers of persons in
various risk ranges; cancer incidence; the maximum non-cancer hazard
index (HI); and the maximum acute non-cancer hazard (72 FR 25138, May
3, 2007; 71 FR 42724, July 27, 2006). In our most recent proposals (75
FR 65068, October 21, 2010 and 75 FR 80220, December 21, 2010), EPA
also presented and considered additional measures of health
information, including: estimates of ``facility-wide'' risks (risks
from all HAP emissions from the facility at which the source category
is located); \4\ demographic analyses (analyses of the distributions of
HAP-related risks across different social, demographic, and economic
groups living near the facilities); and estimates of the risks
associated with the maximum level of emissions which might be allowed
by the current MACT standards (see, e.g., 75 FR 65068, October 21, 2010
and 75 FR 80220, December 21, 2010). EPA also discussed and considered
risk estimation uncertainties. EPA is providing this same type of
information in support of the proposed actions described in this
Federal Register notice.
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\4\ EPA previously provided estimates of total facility risk in
a residual risk proposal for coke oven batteries (69 FR 48338,
August 9, 2004).
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The Agency is considering all available health information to
inform our determinations of risk acceptability and ample margin of
safety under CAA section 112(f). Specifically, as explained in the
Benzene NESHAP, ``the first step judgment on acceptability cannot be
reduced to any single factor'' and thus ``[t]he Administrator believes
that the acceptability of risk under section 112 is best judged on the
basis of a broad set of health risk measures and information.'' 54 FR
at 38046. Similarly, with regard to making the ample margin of safety
determination, as stated in the Benzene NESHAP ``[I]n the ample margin
decision, the Agency again considers all of the health risk and other
health information considered in the first step. Beyond that
information, additional factors relating to the appropriate level of
control will also be considered, including cost and economic impacts of
controls, technological feasibility, uncertainties, and any other
relevant factors.'' Id.
The Agency acknowledges that flexibility is provided by the Benzene
NESHAP regarding what factors EPA might consider in making
determinations and how they might be weighed for each source category.
In responding to comment on our policy under the Benzene NESHAP, EPA
explained that: ``The policy chosen by the Administrator permits
consideration of multiple measures of health risk. Not only can the MIR
figure be considered, but also incidence, the presence of non-cancer
health effects, and the uncertainties of the risk estimates. In this
way, the effect on the most exposed individuals can be reviewed as well
as the impact on the general public. These factors can then be weighed
in each individual case. This approach complies with the Vinyl Chloride
mandate that the Administrator ascertain an acceptable level of risk to
the public by employing [her] expertise to assess available data. It
also complies with the Congressional intent behind the CAA, which did
not exclude the use of any particular measure of public health risk
from the EPA's consideration with respect to CAA section 112
regulations, and, thereby, implicitly permits consideration of any and
all measures of health risk which the Administrator, in [her] judgment,
believes are appropriate to determining what will `protect the public
health.' '' 54 FR at 38057.
For example, the level of the MIR is only one factor to be weighed
in
[[Page 9415]]
determining acceptability of risks. It is explained in the Benzene
NESHAP that ``an MIR of approximately 1-in-10 thousand should
ordinarily be the upper end of the range of acceptability. As risks
increase above this benchmark, they become presumptively less
acceptable under CAA section 112, and would be weighed with the other
health risk measures and information in making an overall judgment on
acceptability. Or, the Agency may find, in a particular case, that a
risk that includes MIR less than the presumptively acceptable level is
unacceptable in the light of other health risk factors.'' Id. at 38045.
Similarly, with regard to the ample margin of safety analysis, EPA
stated in the Benzene NESHAP that: ``* * * EPA believes the relative
weight of the many factors that can be considered in selecting an ample
margin of safety can only be determined for each specific source
category. This occurs mainly because technological and economic factors
(along with the health-related factors) vary from source category to
source category.'' Id. at 38061.
EPA wishes to point out that certain health information has not
been considered to date in making residual risk determinations. In
assessing risks to populations in the vicinity of the facilities in
each category, we present estimates of risk associated with HAP
emissions from the source category alone (source category risk
estimates) and HAP emissions from the entire facility at which the
covered source category is located (facility-wide risk estimates). We
do not attempt to characterize the risks associated with all HAP
emissions impacting the populations living near the sources in these
categories. That is, at this time, we do not attempt to quantify those
HAP risks that may be associated with mobile source emissions, natural
source emissions, persistent environmental pollution, or atmospheric
transformation in the vicinity of the sources in these categories.
The Agency understands the potential importance of considering an
individual's total exposure to HAP in addition to considering exposure
to HAP emissions from the source category and facility. This is
particularly important when assessing non-cancer risks, where
pollutant-specific exposure levels (e.g., Reference Concentration
(RfC)) are based on the assumption that thresholds exist for adverse
health effects. For example, the Agency recognizes that, although
exposures attributable to emissions from a source category or facility
alone may not indicate the potential for increased risk of adverse non-
cancer health effects in a population, the exposures resulting from
emissions from the facility in combination with emissions from all of
the other sources (e.g., other facilities) to which an individual is
exposed may be sufficient to result in increased risk of adverse non-
cancer health effects. In May 2010, the Science Advisory Board (SAB)
advised us ``* * * that RTR assessments will be most useful to decision
makers and communities if results are presented in the broader context
of aggregate and cumulative risks, including background concentrations
and contributions from other sources in the area.'' \5\
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\5\ EPA's responses to this and all other key recommendations of
the SAB's advisory on RTR risk assessment methodologies (which is
available at: http://yosemite.epa.gov/sab/sabproduct.nsf/
4AB3966E263D943A8525771F00668381/$File/EPA-SAB-10-007-unsigned.pdf)
are outlined in a memo to this rulemaking docket from David Guinnup
entitled, EPA's Actions in Response to the Key Recommendations of
the SAB Review of RTR Risk Assessment Methodologies.
---------------------------------------------------------------------------
While we are interested in placing source category and facility-
wide HAP risks in the context of total HAP risks from all sources
combined in the vicinity of each source, we are concerned about the
uncertainties of doing so. At this point, we believe that such
estimates of total HAP risks will have significantly greater associated
uncertainties than for the source category or facility-wide estimates,
and hence compounding the uncertainty in any such comparison. This is
because we have not conducted a detailed technical review of HAP
emissions data for source categories and facilities that have not
previously undergone an RTR review or are not currently undergoing such
review. We are requesting comment on whether and how best to estimate
and evaluate total HAP exposure in our assessments, and, in particular,
on whether and how it might be appropriate to use information from
EPA's National Air Toxics Assessment (NATA) to support such estimates.
We are also seeking comment on how best to consider various types and
scales of risk estimates when making our acceptability and ample margin
of safety determinations under CAA section 112(f). Additionally, we are
seeking comments and recommendations for any other comparative measures
that may be useful in the assessment of the distribution of HAP risks
across potentially affected demographic groups.
C. What other actions are we addressing in this proposal?
1. Startup, Shutdown and Malfunction
This proposed action would amend the provisions of the existing
NESHAP that apply to periods of startup, shutdown, and malfunction
(SSM). The proposed revisions of these provisions result from a Court
decision that vacated portions of two provisions in EPA's ``General
Provisions'' regulation under CAA section 112, governing the emissions
of HAP during periods of SSM. The current Primary Lead Smelting MACT
includes references to the vacated provisions in the General Provisions
rule.
We are proposing to revise the Primary Lead Smelting MACT standard
to require affected sources to comply with the emission limitations at
all times and during periods of SSM. Specifically, we are proposing
several revisions to subpart TTT including revising Table 1 to indicate
that the requirements of the General Provisions pertaining to SSM do
not apply and to revise language in Sec. 63.1547 (g)(1) and (2) to
remove the exemption for bag leak detection alarm time attributable to
SSM from total allowed alarm time. For reasons discussed below, we are
also proposing to promulgate an affirmative defense to civil penalties
for exceedances of emission standards caused by malfunctions, as well
as criteria for establishing the affirmative defense. These changes
would go into effect upon the effective date of promulgation of the
final rule.
The United States Court of Appeals for the District of Columbia
Circuit vacated portions of two provisions in EPA's CAA Section 112
regulations governing the emissions of HAP during periods of SSM.
Sierra Club v. EPA, 551 F.3d 1019 (D.C. Cir. 2008), cert. denied, 130
S. Ct. 1735 (U.S. 2010). Specifically, the Court vacated the SSM
exemptions contained in 40 CFR 63.6(f)(1) and 40 CFR 63.6(h)(1), that
are part of a regulation commonly known as the ``General Provisions
Rule,'' that EPA had promulgated under section 112 of the CAA. When
incorporated into CAA section 112(d) regulations for specific source
categories, these two provisions exempt sources from the requirement to
comply with the otherwise applicable CAA section 112(d) emission
standard during periods of SSM.
We are proposing the elimination of the SSM exemption in this rule.
Consistent with Sierra Club v. EPA, EPA is proposing standards in this
rule that apply at all times. We are also proposing several revisions
to Table 1 (the General Provisions Applicability table). For
[[Page 9416]]
example, we are proposing to eliminate the incorporation of the General
Provisions' requirement that the source develop an SSM plan. We also
are proposing to eliminate or revise certain recordkeeping and
reporting that relate to the SSM exemption. EPA has attempted to ensure
that we have not included in the proposed regulatory language any
provisions that are inappropriate, unnecessary, or redundant in the
absence of the SSM exemption. We are specifically seeking comment on
whether there are any such provisions that we have inadvertently
incorporated or overlooked.
In proposing standards in this rule, EPA has taken into account
startup and shutdown periods and, for the reasons explained below, has
not proposed different standards for those periods. Information on
periods of startup and shutdown in the industry indicate that emissions
during these periods do not increase. Furthermore, all processes are
controlled by either control devices or work practices and these
controls would not typically be affected by an SSM event. Also,
compliance with the standard already requires averaging of emissions
over a three month period, which accounts for the variability of
emissions that may result during periods of startup and shutdown.
Therefore, separate standards for periods of startup and shutdown are
not being proposed.
Periods of startup, normal operations, and shutdown are all
predictable and routine aspects of a source's operations. However, by
contrast, malfunction is defined as a ``sudden, infrequent, and not
reasonably preventable failure of air pollution control and monitoring
equipment, process equipment, or a process to operate in a normal or
useful manner * * *'' (40 CFR 63.2). EPA has determined that
malfunctions should not be viewed as a distinct operating mode and,
therefore, any emissions that occur at such times do not need to be
factored into development of CAA section 112(d) standards, which, once
promulgated, apply at all times. In Mossville Environmental Action Now
v. EPA, 370 F.3d 1232, 1242 (D.C. Cir. 2004), the court upheld as
reasonable standards that had factored in variability of emissions
under all operating conditions. However, nothing in section 112(d) or
in case law requires that EPA anticipate and account for the
innumerable types of potential malfunction events in setting emission
standards. See, Weyerhaeuser v. Costle, 590 F.2d 1011, 1058 (D.C. Cir.
1978)(``In the nature of things, no general limit, individual permit,
or even any upset provision can anticipate all upset situations. After
a certain point, the transgression of regulatory limits caused by
`uncontrollable acts of third parties,' such as strikes, sabotage,
operator intoxication or insanity, and a variety of other
eventualities, must be a matter for the administrative exercise of
case-by-case enforcement discretion, not for specification in advance
by regulation.'').
Further, it is reasonable to interpret section 112(d) as not
requiring EPA to account for malfunctions in setting emission
standards. For example, we note that CAA section 112 uses the concept
of ``best performing'' sources in defining MACT, the level of
stringency that major source standards must meet. Applying the concept
of ``best performing'' to a source that is malfunctioning presents
significant difficulties. The goal of best performing sources is to
operate in such a way as to avoid malfunctions of their units.
Moreover, even if malfunctions were considered a distinct operating
mode, we believe it would be impracticable to take malfunctions into
account in setting CAA section 112(d) standards for Primary Lead
Smelting. As noted above, by definition, malfunctions are sudden and
unexpected events and it would be difficult to set a standard that
takes into account the myriad different types of malfunctions that can
occur across all sources in the category. Moreover, malfunctions can
vary in frequency, degree, and duration, further complicating standard
setting.
In the unlikely event that a source fails to comply with the
applicable CAA section 112(d) standards as a result of a malfunction
event, EPA would determine an appropriate response based on, among
other things, the good faith efforts of the source to minimize
emissions during malfunction periods, including preventative and
corrective actions, as well as root cause analyses to ascertain and
rectify excess emissions. EPA would also consider whether the source's
failure to comply with the CAA section 112(d) standard was, in fact,
``sudden, infrequent, not reasonably preventable'' and was not instead
``caused in part by poor maintenance or careless operation.'' 40 CFR
63.2 (definition of malfunction).
Finally, EPA recognizes that even equipment that is properly
designed and maintained can sometimes fail and that such failure can
sometimes cause or contribute to an exceedance of the relevant emission
standard. (See, e.g., State Implementation Plans: Policy Regarding
Excessive Emissions During Malfunctions, Startup, and Shutdown (Sept.
20, 1999); Policy on Excess Emissions During Startup, Shutdown,
Maintenance, and Malfunctions (Feb. 15, 1983).) EPA is therefore
proposing to add to the final rule an affirmative defense to civil
penalties for exceedances of emission limits that are caused by
malfunctions. See 40 CFR 63.1542 (defining ``affirmative defense'' to
mean, in the context of an enforcement proceeding, a response or
defense put forward by a defendant, regarding which the defendant has
the burden of proof, and the merits of which are independently and
objectively evaluated in a judicial or administrative proceeding). We
also are proposing other regulatory provisions to specify the elements
that are necessary to establish this affirmative defense; the source
must prove by a preponderance of the evidence that it has met all of
the elements set forth in Sec. 63.1551. (See 40 CFR 22.24.) The
criteria ensure that the affirmative defense is available only where
the event that causes an exceedance of the emission limit meets the
narrow definition of malfunction in 40 CFR 63.2 (sudden, infrequent,
not reasonably preventable and not caused by poor maintenance and/or
careless operation). For example, to successfully assert the
affirmative defense, the source must prove by a preponderance of the
evidence that excess emissions ``[w]ere caused by a sudden, short,
infrequent, and unavoidable failure of air pollution control and
monitoring equipment, process equipment, or a process to operate in a
normal or usual manner * * *'' The criteria also are designed to ensure
that steps are taken to correct the malfunction, to minimize emissions
in accordance with Sec. Sec. 63.1543(i) and 63.1544(e) and to prevent
future malfunctions. For example, the source must prove by a
preponderance of the evidence that ``[r]epairs were made as
expeditiously as possible when the applicable emission limitations were
being exceeded * * *'' and that ``[a]ll possible steps were taken to
minimize the impact of the excess emissions on ambient air quality, the
environment and human health * * *.'' In any judicial or administrative
proceeding, the Administrator may challenge the assertion of the
affirmative defense and, if the respondent has not met its burden of
proving all of the requirements in the affirmative defense, appropriate
penalties may be assessed in accordance with section 113 of the Clean
Air Act (see also 40 CFR part 22.77).
Specifically, we are proposing the following changes to the rule.
Added general duty requirements in Sec. Sec. 63.1543 and
63.1544 to replace General Provision requirements that reference
vacated SSM provisions.
[[Page 9417]]
Added replacement language that eliminates the reference
to SSM exemptions applicable to performance tests in Sec. 63.1546.
Added paragraphs in Sec. 63.1549(e) requiring the
reporting of malfunctions as part of the affirmative defense
provisions.
Added paragraphs in Sec. 63.1549(b) requiring the keeping
of certain records during malfunctions as part of the affirmative
defense provisions.
Revised Table 1 to reflect changes in the applicability of
the General Provisions to this subpart resulting from a court vacatur
of certain SSM requirements in the General Provisions.
2. Lead as a Surrogate and Regulation of Volatile Organic Compounds
(VOC) and Acid Gas Emissions
In a January 14, 2009, petition for rulemaking filed by the Natural
Resources Defense Council and Sierra Club, the petitioners claim that
for the Primary Lead Smelting MACT, EPA relied on lead as a surrogate
for all HAP and they claim that it was inappropriate for EPA to do so
in absence of a showing that lead is an appropriate surrogate for all
other HAP (such as mercury, acid gases, and volatile organic compounds
(VOC)). The petitioners asserted that EPA should set standards for
other HAP absent a showing that lead is an appropriate surrogate for
these HAP. They also assert that EPA's PM standard does not reflect the
emission level achieved by the best performing sources and that EPA
must re-open the rule to set floors for PM in accordance with CAA
section 112(d)(3). A copy of the petition is included in the docket.
As part of this rulemaking, EPA is responding to the claims made by
the petitioners regarding the Primary Lead Smelting MACT.
As an initial matter, the petitioners are incorrect in their claim
that EPA considers lead as a surrogate for all HAP. Rather, EPA used
lead as a surrogate only for other metal HAP compounds in establishing
the emissions limit in the current MACT standard for this source
category (63 FR 19206 and 64 FR 30195). EPA determined in the 1999 rule
that lead, a nonvolatile metal HAP, is an appropriate surrogate for
other nonvolatile metal HAP including antimony, arsenic, chromium,
nickel, manganese, and cadmium. In the proposed rule for the Primary
Lead Smelting MACT (63 FR 19206), EPA discussed the use of lead as a
surrogate for metal HAP emissions and explained that strong
correlations exist between emissions of lead and other metal HAP and
that the technologies identified for the control of metal HAP are the
same as those used to control lead emissions. Therefore, EPA expected
that the standards requiring control of lead would achieve similar
control of the other metal HAP emitted from primary lead smelters. No
adverse comments were received regarding EPA's proposed rationale for
relying on lead as a surrogate for other metal HAP emitted by these
sources and EPA adopted that rationale in the final rule promulgating
the Primary Lead Smelting MACT. The petitioners do not have any
substantive basis as to why EPA's rationale is not supported. Nor do
they claim that there is any new information that would support re-
opening this issue. Thus they fail to present a basis for re-opening
this issue.
The petitioners also insist that EPA should have set standards for
VOC and acid gases that are HAP because lead would not be a surrogate
for these pollutants. EPA noted in the original proposal that due to
small amounts of coke fed to the blast furnace, organic HAP (VOC) was
emitted at a rate so low as to be infeasible to reduce. Again, no
adverse comments were received on EPA's proposed conclusions, which
were adopted in the final rule, and the petitioners do not now provide
substantive support for their claim. Nor do they explain why any such
claim could not have been raised during the initial rulemaking. Thus,
they fail to present a basis for re-opening the rule on this issue.
Finally, petitioners claim that the ``PM standard does not reflect
the emission level achieved by the best performing sources.'' This
claim is unclear as there is no PM standard in the Primary Lead
Smelting MACT. The monitoring provisions provide that PM should be
measured in relation to a predetermined PM level as one test for
indicating baghouse performance. However, the PM levels are not
enforceable emission limits, but merely an indication that the baghouse
may not be operating properly. Again, these provisions were clearly
explained in the proposed and final Primary Lead Smelting MACT
rulemakings. Any claims concerning the appropriateness of these
monitoring requirements should have been raised during the initial
rulemaking process. Petitioners do not claim any new grounds for
raising this issue now. Thus, the petition fails to provide a basis for
re-opening the MACT.
3. Modification of the Applicability Provision
EPA is proposing to amend the applicability section to apply to any
facility processing lead ore concentrate to produce lead metal. Under
the current applicability provisions, the affected sources include any
sinter machine, blast furnace, dross furnace, process fugitive source,
and fugitive dust source located at a primary lead smelter and excludes
secondary lead smelters, lead refiners, or lead remelters. Combined
with the current definition for ``primary lead smelter,'' the current
rule effectively only applies to facilities that produce lead metal
from lead sulfide ore concentrates using pyrometallurgical techniques.
While the only processes available for the production of lead from lead
ore concentrate at the time the MACT rule was developed were
pyrometallurgical techniques, that applicability language is narrower
than the primary lead smelting source category description EPA
identified in its source category listing issued pursuant to CAA
section 112(c)(1), Documentation for Developing the Initial Source
Category List (EPA-450/3-91-030, July 1992). In the source category
listing, EPA defined the primary lead smelting source category as
follows: ``The Primary Lead Smelting source category includes any
facility engaged in producing lead metal from ore concentrates. The
category includes, but is not limited to, the following smelting
processes: sintering reduction, preliminary treatment, and refining
operations. The sintering process includes an updraft or downdraft
sintering machine. The reduction process includes the blast furnace,
electric smelting furnace with a converter or reverberatory furnace,
and slag fuming furnace process units. The preliminary treatment
process includes the drossing kettles and dross reverberatory furnace
process units. The refining process includes the refinery process
unit.'' The definition is clear that the primary intent was to cover
sources that produce lead metal from ore concentrates, which would
``include'' the use of a pyrometallurgical process, but would not be
limited to such. As noted previously, at the time we promulgated the
MACT standard, the only method of producing lead metal from ore
concentrates was through use of pyrometallurgical techniques and we
adopted an applicability provision that focused on that process.
However, information provided by the sole operating primary lead
smelting facility indicates that lead production is likely to continue
at the current Doe Run facility, although using a process other than a
pyrometallurgical technique. The new lead facility would continue to
process lead ore concentrate
[[Page 9418]]
in order to produce lead metal. Based on the current applicability
section and definitions, it could be interpreted that the future lead
producing process, using techniques other than pyrometallurgical, would
not be subject to the NESHAP for primary lead smelters. Such a limited
interpretation is not consistent with EPA's intent as evidenced by the
broader definition in the source category list. Therefore, EPA is
proposing to amend the applicability section to specify that the MACT
applies to any lead processing facility that produces lead metal from
lead ore concentrate. Consistent with the proposed revision to the
applicability section, we are proposing to remove the definition of
``primary lead smelter'' and add a definition of ``primary lead
processor'' which means any facility engaged in the production of lead
metal from lead sulfide ore concentrates through the use of
pyrometallurgical or other techniques. In addition, we are proposing to
replace ``primary lead smelter'' with ``primary lead processor''
throughout 40 CFR subpart TTT. (Sec. 63.1541 through Sec. 63.1545,
Sec. 63.1547 through Sec. 63.1549). We are specifically asking for
comment on this proposed change in the definition.
Because there is only one primary lead processing facility in the
U.S., there will be no impact of this change on the number of existing
facilities covered by the MACT.
We note, however, that although we are changing the applicability
section to clarify that the MACT applies to all processes for producing
lead metal from ore concentrates, we are not today proposing a specific
MACT standard that would apply to the as-yet undemonstrated
hydrometallurgical process which Doe Run has indicated that it plans to
build at the current Doe Run facility. If and when that process begins
operation, we will consider whether to revise the MACT standard to
specifically address that process or any other new processes. However,
the limits applicable to specific emission sources currently in
operation as specified in the MACT and as revised under CAA sections
112(d)(6) and (f)(2) in this rulemaking would continue to apply to any
emission source at the facility that continues in operation, such as
the refinery. In addition, to the extent that we establish a final air
lead concentration limit as proposed in Sec. 63.1544, those limits
would also continue to apply to the facility. We also are proposing
that the plant-wide emission limit we are proposing today should
continue to apply to any facility that meets the revised applicability
definition, but we are specifically soliciting comment on whether it
should apply.
We are also taking this opportunity to clarify the reference to
``lead refiners'' in the second sentence of the applicability section,
which provides that the MACT standard does not apply to ``secondary
lead smelters, lead refiners, or lead remelters.'' The intent of this
provision was to make clear that secondary lead smelters would not be
subject to the rule because secondary lead smelters were listed as a
separate source category and addressed in a separate MACT standard.
With regard to lead refiners and lead remelters, the intent was to
provide that these activities, to the extent that they are not located
at facilities that produce lead from lead ore concentrate, would not be
subject to the Primary Lead Smelting MACT. However, it was not the
intention of the rule to exempt kettle refining operations included as
part of a primary lead processing facility. Therefore, EPA is proposing
to add definitions for secondary lead smelters, lead refiners, and lead
remelters in the definitions section of this NESHAP in order to further
clarify the exemption in the applicability provisions with regard to
these types of facilities. As this change only clarifies an existing
provision in the rule, there will be no impact to the number of
facilities covered by the rule.
4. Other Changes
The following lists additional minor changes we are proposing. This
list includes rule changes that address editorial errors and plain
language revisions.
As part of EPA's effort to incorporate plain language into
its regulations, replaced the word ``shall'' with ``must.'' (Sec.
63.1543 through Sec. 63.1550)
Correction to the original rule (``thru'' replaced with
``through'' in the definition of ``tapping location''). (Sec. 63.1542)
Minor wording change to definition of ``fugitive dust
source'' to clarify meaning. (Sec. 63.1542)
IV. Analyses Performed and Background of the Source Category and MACT
Standard
As discussed above, in this proposed rule we are proposing action
to address the RTR requirements of CAA sections 112(d)(6) and (f)(2)
for the Primary Lead Smelting MACT standard. In this section, we
describe the analyses performed to support the proposed decisions for
the RTR for this source category and we also include background
information on the source category and the MACT standard.
A. How did we estimate risks posed by the source category?
The EPA conducted a risk assessment that provided estimates of the
MIR posed by the HAP emissions from the one source in the source
category, the distribution of cancer risks within the exposed
populations, cancer incidence, HI for chronic exposures to HAP with the
potential to cause non-cancer health effects, hazard quotients (HQ) for
acute exposures to HAP with the potential to cause non-cancer health
effects, and an evaluation of the potential for adverse environmental
effects. The risk assessments consisted of seven primary steps, as
discussed below.
The docket for this rulemaking contains the following document
which provides more information on the risk assessment inputs and
models: Draft Residual Risk Assessment for the Primary Lead Smelting
Source Category.
1. Establishing the Nature and Magnitude of Actual Emissions and
Identifying the Emissions Release Characteristics
For the Primary Lead Smelting source category, we compiled a
preliminary dataset using readily available information, reviewed the
data, and made changes where necessary. The preliminary dataset was
based on data in the 2002 National Emissions Inventory (NEI) Final
Inventory, Version 1 (made publicly available on February 26, 2006).
The NEI is a database that contains information about sources that emit
criteria air pollutants, their precursors, and HAP. The NEI database
includes estimates of annual air pollutant emissions from point, non-
point, and mobile sources in the 50 States, the District of Columbia,
Puerto Rico, and the Virgin Islands. The EPA collects this information
and releases an updated version of the NEI database every 3 years.
On December 4, 2009, a CAA Section 114 Information Collection
Request (ICR) was issued requesting information from the one facility
in this source category. An updated dataset was created through
incorporation of changes to the dataset from the ICR data review
process and additional information gathered by EPA. The updated dataset
contains information for the one facility in the source category and
was used to conduct the risk assessment and other analyses that form
the basis for the proposed risk and technology reviews. A copy of the
dataset used and documentation of the risk assessment can be found in
the docket.
[[Page 9419]]
2. Establishing the Relationship Between Actual Emissions and MACT-
Allowable Emissions Levels
The available emissions data in the NEI and from other sources
typically represent the estimates of mass of emissions actually emitted
during the specified annual time period. These ``actual'' emission
levels are often lower than the emission levels that a facility might
be allowed to emit and still comply with the MACT standards. The
emissions level allowed to be emitted by the MACT standards is referred
to as the ``MACT-allowable'' emissions level. This represents the
highest emissions level that could be emitted by the facility without
violating the MACT standards.
We discussed the use of both MACT-allowable and actual emissions in
the final Coke Oven Batteries residual risk rule (70 FR 19998-19999,
April 15, 2005) and in the proposed and final Hazardous Organic NESHAP
(HON) residual risk rules (71 FR 34428, June 14, 2006, and 71 FR 76609,
December 21, 2006, respectively). In those previous actions, we noted
that assessing the risks at the MACT-allowable level is inherently
reasonable since these risks reflect the maximum level sources could
emit and still comply with national emission standards. But we also
explained that it is reasonable to consider actual emissions, where
such data are available, in both steps of the risk analysis, in
accordance with the Benzene NESHAP. (54 FR 38044, September 14, 1989.)
It is reasonable to consider actual emissions because sources typically
seek to perform better than required by emission standards to provide
an operational cushion to accommodate the variability in manufacturing
processes and control device performance.
As described above, the actual emissions data were compiled based
on the NEI, information gathered from the facility and State, and
information received in response to the ICR. To estimate emissions at
the MACT-allowable level, we developed a ratio of MACT-allowable to
actual emissions for each source type (i.e., the individual stacks and
the aggregate fugitive emissions) for the one facility in the source
category. This ratio is based on the level of control required by the
MACT standards compared to the level of reported actual emissions and
available information on the level of control achieved by the emissions
controls in use. For example, if there was information to suggest that
an emission point type was being controlled by 98 percent while the
MACT standards required only 92 percent control, we would estimate that
MACT-allowable emissions from that emission point type could be as much
as 4 times higher (8 percent allowable emissions compared with 2
percent actually emitted), and the ratio of MACT-allowable to actual
would be 4:1 for this emission point type. After developing these
ratios for each emission point type at the one facility in this source
category, we next applied these ratios to the maximum chronic risk
estimates from the inhalation risk assessment to obtain maximum risk
estimates based on MACT-allowable emissions. The estimate of MACT-
allowable emissions for the Primary Lead Smelting source category is
described in section V of this preamble.
3. Conducting Dispersion Modeling, Determining Inhalation Exposures,
and Estimating Individual and Population Inhalation Risks
Both long-term and short-term inhalation exposure concentrations
and health risks from the source category addressed in this proposal
were estimated using the Human Exposure Model (Community and Sector
HEM-3 version 1.1.0). The HEM-3 performs three of the primary risk
assessment activities listed above: (1) Conducting dispersion modeling
to estimate the concentrations of HAP in ambient air, (2) estimating
long-term and short-term inhalation exposures to individuals residing
within 50 km of the modeled sources, and (3) estimating individual and
population-level inhalation risks using the exposure estimates and
quantitative dose-response information.
The dispersion model used by HEM-3 is AERMOD, which is one of EPA's
preferred models for assessing pollutant concentrations from industrial
facilities.\6\ To perform the dispersion modeling and to develop the
preliminary risk estimates, HEM-3 draws on three data libraries. The
first is a library of meteorological data, which is used for dispersion
calculations. This library includes 1 year of hourly surface and upper
air observations for 130 meteorological stations, selected to provide
coverage of the United States and Puerto Rico. However, in this
instance, site-specific meteorological data for the one facility in
this source category were supplied by the state of Missouri and used
for the modeling. The data provided by the state of Missouri were for
eight quarters (i.e., eight three-month periods) from April 1997
through June 1999. To obtain one year of meteorological data, we used
the middle portion of these data, the year 1998, in our modeling. A
second library of United States Census Bureau census block \7\ internal
point locations and populations provides the basis of human exposure
calculations (Census, 2000). In addition, for each census block, the
census library includes the elevation and controlling hill height,
which are also used in dispersion calculations. A third library of
pollutant unit risk factors and other health benchmarks is used to
estimate health risks. These risk factors and health benchmarks are the
latest values recommended by EPA for HAP and other toxic air
pollutants. These values are available at http://www.epa.gov/ttn/atw/toxsource/summary.html and are discussed in more detail later in this
section.
---------------------------------------------------------------------------
\6\ U.S. EPA. Revision to the Guideline on Air Quality Models:
Adoption of a Preferred General Purpose (Flat and Complex Terrain)
Dispersion Model and Other Revisions (70 FR 68218, November 9,
2005).
\7\ A census block is generally the smallest geographic area for
which census statistics are tabulated.
---------------------------------------------------------------------------
In developing the risk assessment for chronic exposures, we used
the estimated annual average ambient air concentration of each of the
HAP emitted by each source for which we have emissions data in the
source category. The air concentrations at each nearby census block
centroid were used as a surrogate for the chronic inhalation exposure
concentration for all the people who reside in that census block. We
calculated the MIR for the one facility as the cancer risk associated
with a lifetime (70-year period) of exposure to the maximum
concentration at the centroid of an inhabited census block. Individual
cancer risks were calculated by multiplying the estimated lifetime
exposure to the ambient concentration of each of the HAP (in micrograms
per cubic meter) by its Unit Risk Estimate (URE), which is an upper
bound estimate of an individual's probability of contracting cancer
over a lifetime of exposure to a concentration of 1 microgram of the
pollutant per cubic meter of air. In general, for residual risk
assessments, we use URE values from EPA's Integrated Risk Information
System (IRIS). For carcinogenic pollutants without EPA IRIS values, we
look to other reputable sources of cancer dose-response values, often
using California Environmental Protection Agency (CalEPA) URE values,
where available. In cases where new, scientifically credible dose-
response values have been developed in a manner consistent with EPA
guidelines and have undergone a peer review process similar to that
used by
[[Page 9420]]
EPA, we may use such dose response values in place of, or in addition
to, other values, if appropriate. In this review, IRIS values were
available for both carcinogenic pollutants (cadmium and arsenic)
emitted by the facility in this source category, and therefore IRIS
values were used in the assessment.
Incremental individual lifetime cancer risks associated with
emissions from the one source in the source category were estimated as
the sum of the risks for each of the carcinogenic HAP (including those
classified as carcinogenic to humans, likely to be carcinogenic to
humans, and suggestive evidence of carcinogenic potential \8\) emitted
by the modeled source. Cancer incidence and the distribution of
individual cancer risks for the population within 50 km of the source
were also estimated for the source category as part of these
assessments by summing individual risks. A distance of 50 km is
consistent with both the analysis supporting the 1989 Benzene NESHAP
(54 FR 38044) and the limitations of Gaussian dispersion models,
including AERMOD.
---------------------------------------------------------------------------
\8\ These classifications also coincide with the terms ``known
carcinogen, probable carcinogen, and possible carcinogen,''
respectively, which are the terms advocated in the EPA's previous
Guidelines for Carcinogen Risk Assessment, published in 1986 (51 FR
33992, September 24, 1986). Summing the risks of these individual
compounds to obtain the cumulative cancer risks is an approach that
was recommended by the EPA's SAB in their 2002 peer review of EPA's
NATA entitled, NATA--Evaluating the National-scale Air Toxics
Assessment 1996 Data--an SAB Advisory, available at: http://
yosemite.epa.gov/sab/sabproduct.nsf/
214C6E915BB04E14852570CA007A682C/$File/ecadv02001.pdf.
---------------------------------------------------------------------------
To assess risk of non-cancer health effects from chronic exposures,
we summed the HQ for each of the HAP that affects a common target organ
system to obtain the HI for that target organ system (or target organ-
specific HI, TOSHI). The HQ is the estimated exposure divided by the
chronic reference value, which is either the EPA RfC, defined as ``an
estimate (with uncertainty spanning perhaps an order of magnitude) of a
continuous inhalation exposure to the human population (including
sensitive subgroups) that is likely to be without an appreciable risk
of deleterious effects during a lifetime,'' or, in cases where an RfC
is not available, the Agency for Toxic Substances and Disease Registry
(ATSDR) chronic Minimal Risk Level (MRL) or the CalEPA Chronic
Reference Exposure Level (REL). The REL is defined as ``the
concentration level at or below which no adverse health effects are
anticipated for a specified exposure duration.''
Screening estimates of acute exposures and risks were also
evaluated for each of the HAP at the point of highest off-site exposure
for each facility (i.e., not just the census block centroids) assuming
that a person was located at this spot at a time when both the peak
(hourly) emission rate and hourly dispersion conditions occurred. In
general, acute HQ values were calculated using best available, short-
term dose-response value. These acute dose-response values include REL,
Acute Exposure Guideline Levels (AEGL), and Emergency Response Planning
Guidelines (ERPG) for 1-hour exposure durations. Notably, for HAP
emitted from this source category, REL values were the only such dose-
response values available. As discussed below, we used conservative
assumptions for emission rates, meteorology, and exposure location for
our acute analysis.
As described in the CalEPA's Air Toxics Hot Spots Program Risk
Assessment Guidelines, Part I, The Determination of Acute Reference
Exposure Levels for Airborne Toxicants, an acute REL value (http://www.oehha.ca.gov/air/pdf/acuterel.pdf) is defined as ``the
concentration level at or below which no adverse health effects are
anticipated for a specified exposure duration is termed the REL. REL
values are based on the most sensitive, relevant, adverse health effect
reported in the medical and toxicological literature. REL values are
designed to protect the most sensitive individuals in the population by
the inclusion of margins of safety. Since margins of safety are
incorporated to address data gaps and uncertainties, exceeding the REL
does not automatically indicate an adverse health impact.
To develop screening estimates of acute exposures, we first
developed estimates of maximum hourly emission rates by multiplying the
average actual annual hourly emission rates by a factor to cover
routinely variable emissions. We chose the factor to use based on
process knowledge and engineering judgment and with awareness of a
Texas study of short-term emissions variability, which showed that most
peak emission events, in a heavily-industrialized 4-county area
(Harris, Galveston, Chambers, and Brazoria Counties, Texas) were less
than twice the annual average hourly emission rate. The highest peak
emission event was 74 times the annual average hourly emission rate,
and the 99th percentile ratio of peak hourly emission rate to the
annual average hourly emission rate was 9.\9\ This analysis is provided
in Appendix 4 of the Draft Residual Risk Assessment for Primary Lead
Smelting which is available in the docket for this action. Considering
this analysis, unless specific process knowledge or data are available
to provide an alternate value, to account for more than 99 percent of
the peak hourly emissions, we apply a conservative screening
multiplication factor of 10 to the average annual hourly emission rate
in these acute exposure screening assessments. For the Primary Lead
Smelting source category, this factor of 10 was applied.
---------------------------------------------------------------------------
\9\ See http://www.tceq.state.tx.us/compliance/field_ops/eer/index.html or docket to access the source of these data.
---------------------------------------------------------------------------
In cases where all acute HQ values from the screening step were
less than or equal to 1, acute impacts were deemed negligible and no
further analysis was performed. In the cases where an acute HQ from the
screening step was greater than 1, additional site-specific data were
considered to develop a more refined estimate of the potential for
acute impacts of concern. Ideally, we would prefer to have continuous
measurements over time to see how the emissions vary by each hour over
an entire year. Having a frequency distribution of hourly emission
rates over a year would allow us to perform a probabilistic analysis to
estimate potential threshold exceedances and their frequency of
occurrence. Such an evaluation could include a more complete
statistical treatment of the key parameters and elements adopted in
this screening analysis. However, we recognize that having this level
of data is rare, hence our use of the multiplier (i.e., factor of 10)
approach in our screening analysis.
4. Conducting Multipathway Exposure and Risk Modeling
The potential for significant human health risks due to exposures
via routes other than inhalation (i.e., multipathway exposures) and the
potential for adverse environmental impacts were evaluated in a three-
step process. In the first step, we determined whether any facilities
emitted any HAP known to be persistent and bio-accumulative in the
environment (PB-HAP). There are 14 PB-HAP compounds or compound classes
identified for this screening in EPA's Air Toxics Risk Assessment
Library (available at http://www.epa.gov/ttn/fera/risk_atra_vol1.html). They are cadmium compounds, chlordane, chlorinated
dibenzodioxins and furans, dichlorodiphenyldichloroethylene,
heptachlor, hexachlorobenzene,
[[Page 9421]]
hexachlorocyclohexane, lead compounds, mercury compounds, methoxychlor,
polychlorinated biphenyls, POM, toxaphene, and trifluralin. Emissions
of two PB HAP were identified in the emissions inventory for the
Primary Lead Smelting source category: Lead compounds and cadmium
compounds.
Cadmium emissions were evaluated for potential non-inhalation risks
and adverse environmental impacts using our recently developed
screening scenario that was developed for use with the TRIM.FaTE model.
This screening scenario uses environmental media outputs from the peer-
reviewed TRIM.FaTE to estimate the maximum potential ingestion risks
for any specified emission scenario by using a generic farming/fishing
exposure scenario that simulates a subsistence environment. The
screening scenario retains many of the ingestion and scenario inputs
developed for EPA's Human Health Risk Assessment Protocols (HHRAP) for
hazardous waste combustion facilities. In the development of the
screening scenario a sensitivity analysis was conducted to ensure that
its key design parameters were established such that environmental
media concentrations were not underestimated, and to also minimize the
occurrence of false positives for human health endpoints. See Appendix
3 of the risk assessment document for a complete discussion of the
development and testing of the screening scenario, as well as for the
values of facility-level de minimis emission rates developed for
screening potentially significant multi-pathway impacts. For the
purpose of developing de minimis emission rates for our cadmium multi-
pathway screening, we derived emission levels for cadmium at which the
maximum human health risk would be 1-in-1 million for lifetime cancer
risk.
In evaluating the potential air-related multi-pathway risks from
the emissions of lead compounds from the one facility in this source
category, rather than developing a de minimis emission rate, we
compared its maximum modeled 3-month average atmospheric lead
concentration at any off-site location with the current primary
National Ambient Air Quality Standard (NAAQS) for lead (promulgated in
2008), which is set to a level of 0.15 micro-grams per cubic meter
([micro]g/m\3\) based on a rolling 3-month period with a not-to-be-
exceeded form, and which will require attainment by 2016. 73 FR 66964.
Notably, in making these comparisons, we estimated maximum rolling 3-
month ambient lead concentrations taking into account all of the
elements of the NAAQS for lead. That is, our estimated 3-month lead
concentrations are calculated in a manner that is consistent with the
indicator, averaging time, and form of the NAAQS for lead, and those
estimates are compared to the actual level of the lead NAAQS (0.15
[mu]g/m\3\).
The NAAQS value, a public health policy judgment, incorporated the
Agency's most recent health evaluation of air effects of lead exposure
for the purposes of setting a national standard. In setting this value,
the Administrator promulgated a standard that was requisite to protect
public health with an adequate margin of safety. We consider values
below the level of the primary NAAQS to protect against multi-pathway
risks because, as mentioned above, the primary NAAQS is set as to
protect public health with an adequate margin of safety. However,
ambient air lead concentrations above the NAAQS are considered to pose
the potential for increased risk to public health. We consider this
NAAQS assessment to be a refined analysis given the numerous health
studies, detailed risk and exposure analyses, and level of external
peer and public review that went into the development of the primary
NAAQS for lead, combined with the site-specific dispersion modeling
analysis performed to develop the ambient concentration estimates due
to emissions from the one Primary Lead Processing facility being
addressed in this RTR. It should be noted, however, that this
comparison does not account for possible population exposures to lead
from sources other than the one being modeled; for example, via
consumption of water from untreated local sources or ingestion of
locally grown food. Nevertheless, the Administrator judged that such a
standard, would protect, with an adequate margin of safety, the health
of children and other at-risk populations against an array of adverse
health effects, most notably including neurological effects,
particularly neurobehavioral and neurocognitive effects, in children.
73 FR 67007. The Administrator, in setting the standard, also
recognized that no evidence-or risk based bright line indicated a
single appropriate level. Instead a collection of scientific evidence
and other information was used to select the standard from a range of
reasonable values. 73 FR 67006.
We further note that comparing ambient lead concentrations to the
NAAQS for lead, considering the level, averaging time, form and
indicator, also informs whether there is the potential for adverse
environmental effects. This is because the secondary lead NAAQS, which
has the same averaging time, form, and level as the primary standard,
was set to protect the public welfare which includes among other things
soils, water, crops, vegetation and wildlife. CAA section 302(h). Thus,
ambient lead concentrations above the NAAQS for lead also indicate the
potential for adverse environmental effects.
For additional information on the multi-pathway analysis approach,
see the residual risk documentation as referenced in section IV.A of
this preamble. The EPA solicits comment generally on the modeling
approach used herein to assess air-related lead risks, and specifically
on the use of the lead NAAQS in this analytical construct.
5. Assessing Risks Considering Emissions Control Options
In addition to assessing baseline inhalation risks and screening
for potential multi-pathway risks, we also estimated risks considering
the potential emission reductions that would be achieved by the
particular control options under consideration. The expected emissions
reductions were applied to the specific HAP and emissions points in the
source category dataset to develop corresponding estimates of risk
reductions.
6. Conducting Other Risk-Related Analyses, Including Facility-Wide
Assessments and Demographic Analyses
a. Facility-Wide Risk
To put the source category risks in context, for our residual risk
review, we also examine the risks from the entire ``facility,'' where
the facility includes all HAP-emitting operations within a contiguous
area and under common control. In other words, we examine the HAP
emissions not only from the source category of interest, but also
emissions of HAP from all other emission sources at the facility. In
this rulemaking, for the sole facility in the Primary Lead Smelting
source category, there are no other significant HAP emission sources
present. With the exception of organic HAP sources determined to
present insignificant risk, all HAP sources have been included in the
risk analysis. Therefore, the facility-wide risks are the same as the
source category risk and no separate facility-wide analysis was
necessary.
b. Demographic Analysis
To examine the potential for any environmental justice issues that
might be associated with HAP emissions with this source category, we
evaluated the
[[Page 9422]]
distributions of HAP-related cancer and non-cancer risks across
different social, demographic, and economic groups within the
populations living near the one facility in this source category. The
development of demographic analyses to inform the consideration of
environmental justice issues in EPA rulemakings is evolving. EPA offers
the demographic analyses in this rulemaking to inform the consideration
of potential environmental justice issues, and invites public comment
on the approaches used and the interpretations made from the results,
with the hope that this will support the refinement and improve the
utility of such analyses for future rulemakings.
For the demographic analyses, we focus on the populations within 50
km of any facility with emission sources subject to the MACT standard
(identical to the risk assessment). Based on the emissions for the
source category or the facility, we then identified the populations
that are estimated to have exposures to HAP which result in: (1) Cancer
risks of 1-in-1 million or greater, (2) non-cancer HI of 1 or greater,
and/or (3) ambient lead concentrations above the level of the NAAQS for
lead. We compare the percentages of particular demographic groups
within the focused populations to the total percentages of those
demographic groups nationwide. The results, including other risk
metrics, such as average risks for the exposed populations, are
documented in a technical report in the docket for the source category
covered in this proposal.\10\
---------------------------------------------------------------------------
\10\ Risk and Technology Review--Analysis of Socio-Economic
Factors for Populations Living Near Primary Lead Smelting
Operations.
---------------------------------------------------------------------------
The basis for the risk values used in the demographic analyses for
the one facility subject to the Primary Lead Smelting MACT was the
modeling results based on actual emissions levels obtained from the
HEM-3 model described above. The risk values for each census block were
linked to a database of information from the 2000 decennial census that
includes data on race and ethnicity, age distributions, poverty status,
household incomes, and education level. The Census Department
Landview[supreg] database was the source of the data on race and
ethnicity, and the data on age distributions, poverty status, household
incomes, and education level were obtained from the 2000 Census of
Population and Housing Summary File 3 (SF3) Long Form. While race and
ethnicity census data are available at the census block level, the age
and income census data are only available at the census block group
level (which includes an average of 26 blocks or an average of 1,350
people). Where census data are available at the block group level but
not the block level, we assumed that all census blocks within the block
group have the same distribution of ages and incomes as the block
group.
We focused the analysis on those census blocks where source
category risk results show either estimated lifetime inhalation cancer
risks above 1-in-1 million or chronic non-cancer indices above 1. In
addition, in this case we also focused on those census blocks where
estimated ambient lead concentrations were above the level of the lead
NAAQS. For each of these cases, we determined the relative percentage
of different racial and ethnic groups, different age groups, adults
with and without a high school diploma, people living in households
below the national median income, and for people living below the
poverty line within those census blocks. The specific census population
categories included:
Total population;
White;
African American (or Black);
Native Americans;
Other races and multiracial;
Hispanic or Latino;
People living below the poverty line;
Children 18 years of age and under;
Adults 19 to 64 years of age;
Adults 65 years of age and over;
Adults without a high school diploma.
It should be noted that these categories overlap in some instances,
resulting in some populations being counted in more than one category
(e.g., other races and multiracial and Hispanic). In addition, while
not a specific census population category, we also examined risks to
``Minorities,'' a classification which is defined for these purposes as
all race population categories except white.
The methodology and the results of the demographic analyses for
this source category are included in the technical report available in
the docket for this action. (Risk and Technology Review--Analysis of
Socio-Economic Factors for Populations Living Near Primary Lead
Smelting Operations).
7. Considering Uncertainties in Risk Assessment
Uncertainty and the potential for bias are inherent in all risk
assessments, including that performed for the source category addressed
in this proposal. Although uncertainty exists, we believe the approach
that we took, which used conservative tools and assumptions, ensures
that our decisions are health-protective. A brief discussion of the
uncertainties in the emissions dataset, dispersion modeling, inhalation
exposure estimates, and dose-response relationships follows below. A
more thorough discussion of these uncertainties is included in the risk
assessment documentation (Draft Residual Risk Assessment for Primary
Lead Smelting) available in the docket for this action.
a. Uncertainties in the Emissions Dataset
Although the development of the RTR dataset involved quality
assurance/quality control processes, the accuracy of emissions values
will vary depending on the source of the data, the degree to which data
are incomplete or missing, the degree to which assumptions made to
complete the datasets are accurate, whether and to what extent errors
were made in estimating emissions values, and other factors. The
emission estimates considered in this analysis are annual totals
provided by the facility that do not reflect short-term fluctuations
during the course of a year or variations from year to year. In
contrast, the estimates of peak hourly emission rates for the acute
effects screening assessment were based on multiplication factors
applied to the average annual hourly emission rates (the default factor
of 10 was used for Primary Lead Smelting), which is intended to account
for emission fluctuations due to normal facility operations.
b. Uncertainties in Dispersion Modeling
While the analysis employed EPA's recommended regulatory dispersion
model, AERMOD, we recognize that there is uncertainty in ambient
concentration estimates associated with any model, including AERMOD. In
circumstances where we had to choose between various model options,
where possible, we selected model options (e.g., rural/urban, plume
depletion, chemistry) that provided an overestimate of ambient
concentrations of the HAP rather than an underestimate. However,
because of practicality and data limitation reasons, some factors
(e.g., building downwash) have the potential in some situations to
overestimate or underestimate ambient impacts. Despite these
uncertainties, we believe that at off-site locations and census block
centroids, the approach considered in the dispersion modeling analysis
should generally yield overestimates of ambient HAP concentrations.
[[Page 9423]]
c. Uncertainties in Inhalation Exposure
The effects of human mobility on exposures were not included in the
assessment. Specifically, short-term mobility and long-term mobility
between census blocks in the modeling domain were not considered.\11\
As a result, this simplification will likely bias the assessment toward
overestimating the highest exposures. In addition, the assessment
predicted the chronic exposures at the centroid of each populated
census block as surrogates for the exposure concentrations for all
people living in that block. Using the census block centroid to predict
chronic exposures tends to over-predict exposures for people in the
census block who live farther from the facility, and under-predict
exposures for people in the census block who live closer to the
facility. Thus, using the census block centroid to predict chronic
exposures may lead to a potential understatement or overstatement of
the true maximum impact for any one individual, but is an unbiased
estimate of average risk and incidence.
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\11\ Short-term mobility is movement from one microenvironment
to another over the course of hours or days. Long-term mobility is
movement from one residence to another over the course of a
lifetime.
---------------------------------------------------------------------------
The assessments evaluate the projected cancer inhalation risks
associated with pollutant exposures over a 70-year period, which is the
assumed lifetime of an individual. In reality, both the length of time
that modeled emissions sources at facilities actually operate (i.e.,
more or less than 70 years), and the domestic growth or decline of the
modeled industry (i.e., the increase or decrease in the number or size
of United States facilities), will influence the future risks posed by
a given source or source category. Depending on the characteristics of
the industry, these factors will, in most cases, result in an
overestimate both in individual risk levels and in the total estimated
number of cancer cases. However, in rare cases, where a facility
maintains or increases its emission levels beyond 70 years, residents
live beyond 70 years at the same location, and the residents spend most
of their days at that location, then the risks could potentially be
underestimated. Annual cancer incidence estimates from exposures to
emissions from these sources would not be affected by uncertainty in
the length of time emissions sources operate. For the specific source
in this source category we anticipate significant reduction in
activities and emissions in the relatively near future. If this
happens, chronic risks based on the continuation of current emission
levels will be over estimated.
The exposure estimates used in these analyses assume chronic
exposures to ambient levels of pollutants. Because most people spend
the majority of their time indoors, actual exposures may not be as
high, depending on the characteristics of the pollutants modeled. For
many of the HAP, indoor levels are roughly equivalent to ambient
levels, but for very reactive pollutants or larger particles, these
levels are typically lower. This factor has the potential to result in
an overstatement of 25 to 30 percent of exposures.\12\
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\12\ U.S. EPA. National-Scale Air Toxics Assessment for 1996.
(EPA 453/R-01-003; January 2001; page 85.)
---------------------------------------------------------------------------
In addition to the uncertainties highlighted above, there are
several factors specific to the acute exposure assessment that should
be highlighted. The accuracy of an acute inhalation exposure assessment
depends on the simultaneous occurrence of independent factors that may
vary greatly, such as hourly emissions rates, meteorology, and human
activity patterns. In this assessment, we assume that individuals
remain for 1 hour at the point of maximum ambient concentration as
determined by the co-occurrence of peak emissions and worst-case
meteorological conditions. These assumptions would tend to overestimate
actual exposures since it is unlikely that a person would be located at
the point of maximum exposure during the time of worst-case impact.
d. Uncertainties in Dose-Response Relationships
There are uncertainties inherent in the development of the dose-
response values used in our risk assessments for cancer effects from
chronic exposures and non-cancer effects from both chronic and acute
exposures. Some uncertainties may be considered quantitatively, and
others generally are expressed in qualitative terms. We note as a
preface to this discussion a point on dose-response uncertainty that is
brought out in EPA's 2005 Cancer Guidelines; namely, that ``the primary
goal of EPA actions is protection of human health; accordingly, as an
Agency policy, risk assessment procedures, including default options
that are used in the absence of scientific data to the contrary, should
be health protective.'' (EPA 2005 Cancer Guidelines, pages 1-7.) This
is the approach followed here as summarized in the next several
paragraphs. A complete detailed discussion of uncertainties and
variabilities in dose-response relationships is given in the residual
risk documentation which is available in the docket for this action.
Cancer URE values used in our risk assessments are those that have
been developed to generally provide an upper bound estimate of risk.
That is, they represent a ``plausible upper limit to the true value of
a quantity'' (although this is usually not a true statistical
confidence limit).\13\ In some circumstances, the true risk could be as
low as zero; however, in other circumstances the risk could be
greater.\14\ When developing an upper bound estimate of risk and to
provide risk values that do not underestimate risk, health-protective
default approaches are generally used. To err on the side of ensuring
adequate health-protection, EPA typically uses the upper bound
estimates rather than lower bound or central tendency estimates in our
risk assessments, an approach that may have limitations for other uses
(e.g., priority-setting or expected benefits analysis).
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\13\ IRIS glossary (http://www.epa.gov/NCEA/iris/help_gloss.htm).
\14\ An exception to this is the URE for benzene, which is
considered to cover a range of values, each end of which is
considered to be equally plausible, and which is based on maximum
likelihood estimates.
---------------------------------------------------------------------------
Chronic non-cancer reference (RfC and RfD) values represent chronic
exposure levels that are intended to be health-protective levels.
Specifically, these values provide an estimate (with uncertainty
spanning perhaps an order of magnitude) of a continuous inhalation
exposure (RfC) or a daily oral exposure (RfD) to the human population
(including sensitive subgroups) that is likely to be without an
appreciable risk of deleterious effects during a lifetime. To derive
values that are intended to be ``without appreciable risk,'' the
methodology relies upon an uncertainty factor (UF) approach (U.S. EPA,
1993, 1994) which includes consideration of both uncertainty and
variability. When there are gaps in the available information, UF are
applied to derive reference values that are intended to protect against
appreciable risk of deleterious effects. The UF are commonly default
values,\15\ e.g., factors
[[Page 9424]]
of 10 or 3, used in the absence of compound-specific data; where data
are available, UF may also be developed using compound-specific
information. When data are limited, more assumptions are needed and
more UF are used. Thus, there may be a greater tendency to overestimate
risk in the sense that further study might support development of
reference values that are higher (i.e., less potent) because fewer
default assumptions are needed. However, for some pollutants, it is
possible that risks may be underestimated.
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\15\ According to the NRC report, Science and Judgment in Risk
Assessment (NRC, 1994) ``[Default] options are generic approaches,
based on general scientific knowledge and policy judgment, that are
applied to various elements of the risk assessment process when the
correct scientific model is unknown or uncertain.'' The 1983 NRC
report, Risk Assessment in the Federal Government: Managing the
Process, defined default option as ``the option chosen on the basis
of risk assessment policy that appears to be the best choice in the
absence of data to the contrary'' (NRC, 1983a, p. 63). Therefore,
default options are not rules that bind the Agency; rather, the
Agency may depart from them in evaluating the risks posed by a
specific substance when it believes this to be appropriate. In
keeping with EPA's goal of protecting public health and the
environment, default assumptions are used to ensure that risk to
chemicals is not underestimated (although defaults are not intended
to overtly overestimate risk). See EPA, 2004, An Examination of EPA
Risk Assessment Principles and Practices, EPA/100/B-04/001 available
at: http://www.epa.gov/osa/pdfs/ratf-final.pdf.
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While collectively termed ``UF,'' these factors account for a
number of different quantitative considerations when using observed
animal (usually rodent) or human toxicity data in the development of
the RfC. The UF are intended to account for: (1) Variation in
susceptibility among the members of the human population (i.e., inter-
individual variability); (2) uncertainty in extrapolating from
experimental animal data to humans (i.e., interspecies differences);
(3) uncertainty in extrapolating from data obtained in a study with
less-than-lifetime exposure (i.e., extrapolating from sub-chronic to
chronic exposure); (4) uncertainty in extrapolating the observed data
to obtain an estimate of the exposure associated with no adverse
effects; and (5) uncertainty when the database is incomplete or there
are problems with the applicability of available studies. Many of the
UF used to account for variability and uncertainty in the development
of acute reference values are quite similar to those developed for
chronic durations, but they more often use individual UF values that
may be less than 10. UF are applied based on chemical-specific or
health effect-specific information (e.g., simple irritation effects do
not vary appreciably between human individuals, hence a value of 3 is
typically used), or based on the purpose for the reference value (see
the following paragraph). The UF applied in acute reference value
derivation include: (1) Heterogeneity among humans; (2) uncertainty in
extrapolating from animals to humans; (3) uncertainty in lowest
observed adverse effect (exposure) level to no observed adverse effect
(exposure) level adjustments; and (4) uncertainty in accounting for an
incomplete database on toxic effects of potential concern. Additional
adjustments are often applied to account for uncertainty in
extrapolation from observations at one exposure duration (e.g., 4
hours) to derive an acute reference value at another exposure duration
(e.g., 1 hour).
As further discussed below, there is no RfD or other comparable
chronic health benchmark value for lead compounds. Thus, to address
multipathway human health and environmental risks associated with
emissions of lead from this facility, ambient lead concentrations were
compared to the NAAQS for lead. In developing the NAAQS for lead, EPA
considered human health evidence reporting adverse health effects
associated with lead exposure, as well as an EPA conducted multipathway
risk assessment that applied models to estimate human exposures to air-
related lead and the associated risk (73 FR 66979). EPA also explicitly
considered the uncertainties associated with both the human health
evidence and the exposure and risk analyses when developing the NAAQS
for lead. For example, EPA considered uncertainties in the relationship
between ambient air lead and blood lead levels (73 FR 66974), as well
as uncertainties between blood lead levels and loss of IQ points in
children (73 FR 66981).
In considering the evidence and risk analyses and their associated
uncertainties, the EPA Administrator noted his view that there is no
evidence- or risk-based bright line that indicates a single appropriate
level. Instead, he noted, there is a collection of scientific evidence
and judgments and other information, including information about the
uncertainties inherent in many relevant factors, which needs to be
considered together in making this public health policy judgment and in
selecting a standard level from a range of reasonable values (73 FR
66998). In so doing, the Administrator decided that, a level for the
primary lead standard of 0.15 [mu]g/m\3\, in combination with the
specified choice of indicator, averaging time, and form, is requisite
to protect public health, including the health of sensitive groups,
with an adequate margin of safety (73 FR 67006). A thorough discussion
of the health evidence, risk and exposure analyses, and their
associated uncertainties can be found in EPA's final rule revising the
lead NAAQS (73 FR 66970-66981, November 12, 2008).
We also note the uncertainties associated with the health-based
(i.e., primary) NAAQS are likely less than the uncertainties associated
with dose-response values developed for many of the other HAP,
particularly those HAP for which no human health data exist. In 1988,
EPA's IRIS program reviewed the health effects data regarding lead and
its inorganic compounds and determined that it would be inappropriate
to develop an RfD for these compounds, saying, ``A great deal of
information on the health effects of lead has been obtained through
decades of medical observation and scientific research. This
information has been assessed in the development of air and water
quality criteria by the Agency's Office of Health and Environmental
Assessment (OHEA) in support of regulatory decision-making by the
Office of Air Quality Planning and Standards (OAQPS) and by the Office
of Drinking Water (ODW). By comparison to most other environmental
toxicants, the degree of uncertainty about the health effects of lead
is quite low. It appears that some of these effects, particularly
changes in the levels of certain blood enzymes and in aspects of
children's neurobehavioral development, may occur at blood lead levels
so low as to be essentially without a threshold. The Agency's RfD Work
Group discussed inorganic lead (and lead compounds) at two meetings
(07/08/1985 and 07/22/1985) and considered it inappropriate to develop
an RfD for inorganic lead.'' EPA's IRIS assessment for Lead and
compounds (inorganic) (CASRN 7439-92-1), http://www.epa.gov/iris/subst/0277.htm.
We also note that because of the multi-pathway, multi-media impacts
of lead, the risk assessment supporting the NAAQS considered direct
inhalation exposures and indirect air-related multi-pathway exposures
from industrial sources like primary and secondary lead smelting
operations. It also considered background lead exposures from other
sources (like contaminated drinking water and exposure to lead-based
paints). In revising the NAAQS for lead, we note that the Administrator
placed more weight on the evidence-based framework and less weight on
the results from the risk assessment, although he did find the risk
estimates to be roughly consistent with and generally supportive of the
evidence-based framework applied in the NAAQS determination. 73 FR
67004. Thus, when revising the NAAQS for lead to protect public health
with an adequate margin of safety, EPA considered both
[[Page 9425]]
the health evidence and the risk assessment, albeit to different
extents.
In addition to the uncertainties discussed above with respect to
chronic, cancer, and the lead NAAQS reference values, there are also
uncertainties associated with acute reference values. Not all acute
reference values are developed for the same purpose, and care must be
taken when interpreting the results of an acute assessment of human
health effects relative to the reference value or values being
exceeded. Where relevant to the estimated exposures, the lack of short-
term dose-response values at different levels of severity should be
factored into the risk characterization as potential uncertainties.
Although every effort is made to identify peer-reviewed reference
values for cancer and non-cancer effects for all pollutants emitted by
the sources included in this assessment, some hazardous air pollutants
continue to have no peer-reviewed reference values for cancer or
chronic non-cancer or acute effects. Since exposures to these
pollutants cannot be included in a quantitative risk estimate, an
understatement of risk for these pollutants at environmental exposure
levels is possible.
Additionally, chronic reference values for several of the compounds
included in this assessment are currently under EPA IRIS review (e.g.,
cadmium and nickel), and revised assessments may determine that these
pollutants are more or less potent than the current value. We may re-
evaluate residual risks for the final rulemaking if, as a result of
these reviews, a dose-response metric changes enough to indicate that
the risk assessment supporting this notice may significantly understate
human health risk.
e. Uncertainties in the Multipathway and Environmental Effects
Assessment
We generally assume that when exposure levels are not anticipated
to adversely affect human health, they also are not anticipated to
adversely affect the environment. For each source category, we
generally rely on the site-specific levels of PB-HAP emissions to
determine whether a full assessment of the multi-pathway and
environmental effects is necessary. For PB-HAPS other than lead (i.e.,
cadmium), site-specific PB-HAP emission levels were far below levels
which would trigger a refined assessment of multi-pathway impacts, thus
we are confident that these types of impacts are insignificant for the
one facility in this source category.
f. Uncertainties in the Facility-Wide Risk Assessment
We did not conduct a separate facility-wide risk assessment for
this proposal because all of the HAP emission sources at the one
facility subject to the MACT are covered by the MACT standard under
review. Thus, the level of the facility-wide HAP emissions is the same
as the level of emissions from the emissions sources subject to the
MACT standard under review.
g. Uncertainties in the Demographic Analysis
Our analysis of the distribution of risks across various
demographic groups is subject to the typical uncertainties associated
with census data (e.g., errors in filling out and transcribing census
forms), as well as the additional uncertainties associated with the
extrapolation of census-block group data (e.g., income level and
education level) down to the census block level.
B. How did we perform the technology review?
Our technology review is focused on the identification and
evaluation of developments in practices, processes, and control
technologies. If a review of available information identifies such
developments, then we conduct an analysis of the technical feasibility
of these developments, along with the impacts (costs, emission
reductions, risk reductions, etc.). We then make a decision on whether
it is necessary to amend the regulation to require any identified
developments.
Based on specific knowledge of the primary lead smelting source
category, we began by identifying known developments in practices,
processes, and control technologies. For the purpose of this exercise,
we considered any of the following to be a ``development'':
Any add-on control technology or other equipment that was
not identified and considered during MACT development;
Any improvements in add-on control technology or other
equipment (that was identified and considered during MACT development)
that could result in significant additional emission reduction;
Any work practice or operational procedure that was not
identified and considered during MACT development; and
Any process change or pollution prevention alternative
that could be broadly applied that was not identified and considered
during MACT development.
In addition to looking back at practices, processes, or control
technologies reviewed at the time we developed the MACT standards, we
reviewed a variety of sources of data to aid in our evaluation of
whether there were additional practices, processes, or controls to
consider. One of these sources of data was subsequent air toxics rules.
Since the promulgation of the MACT standard for the primary lead
smelting source category addressed in this proposal, EPA has developed
air toxics regulations for a number of additional source categories. We
reviewed the regulatory requirements and/or technical analyses
associated with these subsequent regulatory actions to identify any
practices, processes, and control technologies considered in these
efforts that could possibly be applied to emission sources in the
primary lead smelting source category.
We also consulted EPA's RACT/BACT/LAER Clearinghouse (RBLC). The
terms ``RACT,'' ``BACT,'' and ``LAER'' are acronyms for different
program requirements under the CAA provisions addressing the national
ambient air quality standards. Control technologies, classified as RACT
(Reasonably Available Control Technology), BACT (Best Available Control
Technology), or LAER (Lowest Achievable Emission Rate) apply to
stationary sources depending on whether the sources are existing or
new, and on the size, age, and location of the facility. BACT and LAER
(and sometimes RACT) are determined on a case-by-case basis, usually by
state or local permitting agencies. EPA established the RBLC to provide
a central database of air pollution technology information (including
technologies required in source-specific permits) to promote the
sharing of information among permitting agencies and to aid in
identifying future possible control technology options that might apply
broadly to numerous sources within a category or apply only on a
source-by-source basis. The RBLC contains over 5,000 air pollution
control permit determinations that can help identify appropriate
technologies to mitigate many air pollutant emission streams. We
searched this database to determine whether any practices, processes,
or control technologies are included for the types of processes covered
by the primary lead smelting MACT.
We also requested information from the facility regarding
developments in practices, processes, or control technology. Finally,
we reviewed other information sources, such as state or
[[Page 9426]]
local permitting agency databases and industry-supported databases.
C. Overview of the Source Category and MACT Standards
1. Source Category and MACT Standard
The National Emission Standard for Primary Lead Smelting (or MACT
rule) was promulgated on June 4, 1999 (64 FR 30194) and codified at 40
CFR part 63, subpart TTT. As promulgated in 1999, the MACT standard
applies to affected sources of HAP at primary lead smelters.\16\ The
MACT defines ``Primary lead smelters'' as ``any facility engaged in the
production of lead metal from lead sulfide ore concentrates through the
use of pyrometallurgical techniques.'' 40 CFR 63.1542. The MACT
standard for the Primary Lead Smelting source category does not apply
to secondary lead smelters, lead remelters, or lead refiners (Sec.
63.1541). Today there is one facility (The Doe Run Company in
Herculaneum, Missouri) operating that is subject to the MACT standards
(See Section V.A. below).
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\16\ As provided above in section III(C)(3), we are proposing to
change the standard to apply to Primary Lead Processors.
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At the time of promulgation of the Primary Lead Smelting MACT rule,
there were three operating lead smelters. Due to economic pressures
(decreased market demand for lead) and regulatory pressures, two of the
lead smelting facilities subject to the MACT standard have since been
permanently closed, leaving one primary lead smelter currently
operating in the United States. No new primary lead smelters have been
built in the last 20 years, and no new primary lead processing
facilities using pyrometallurgical techniques are anticipated in the
foreseeable future. The one operating lead smelter is not collocated
with other sources of HAP emissions.
Lead is used to make various construction and consumer products
such as batteries, paint, glass, piping, and filler. Lead sulfide (PbS)
ore concentrates are the main feed material to primary lead smelters.
The primary lead smelting process consists of lead sulfide concentrate
storage and handling, sintering of ore concentrates, sinter crushing
and handling, smelting of sinter to lead metal, drossing (i.e.,
removing the solid oxide deposits), refining and alloying of lead
metal, and smelting of the drosses.
HAP are emitted from primary lead smelting as process emissions
(stack), process fugitive emissions, and fugitive dust emissions.
Process emissions are associated with the exhaust gases from sinter
machines and blast and dross furnaces. HAP expected in process
emissions are metals (mostly lead compounds, but also some arsenic,
cadmium, and other metals) and also may include small amounts of
organic compounds that result from incomplete combustion of coke, which
is charged along with sinter to the blast furnace. Process fugitive
emissions occur at various points during the smelting process (such as
during charging and tapping of furnaces) and the only HAP emitted are
metal HAP. Fugitive dust emissions result from the entrainment of dust
due to material handling, vehicle traffic, and wind erosion from
storage piles and the only HAP emitted are metal HAP.
The MACT standard (40 CFR part 63, subpart TTT) applies to process
emissions (stack) from sinter machines, blast furnaces, and dross
furnaces; process fugitive emissions from sinter, blast furnace,
drossing and refining processes, concentrate handling, and locations
around such processes; and fugitive dust emission sources, such as
roadways, storage piles and the plant yard. Process emissions of lead
compounds from sinter machines, blast furnaces, and dross furnaces, and
process fugitive emissions from the blast furnace and dross furnace
charging, blast furnace and dross furnace tapping, and the sinter
machine (charging, discharging, crushing, and sizing) are limited to
500 grams (g) of lead emissions per mega gram (Mg) of lead produced
(500 g/Mg), which is equal to 1.0 pound (lb) of lead emissions per ton
of lead produced (1 lb/ton). 40 CFR 63.1542(a). A plant-wide limit
format was used for MACT because it was consistent with SIPs, the
commingling of exhaust gases from processes to a single stack made it
impossible to set limits for individual sources, it gave the facilities
more flexibility in complying with the standard, and it promoted
pollution prevention by giving each facility the ability to meet the
emission limit through any combination of source reduction and control
technology options. (63 FR 19208).
In addition to being subject to the plant-wide emission limit of
the standard, process fugitive emissions must be captured by a hood and
ventilated to a baghouse or equivalent control device and the hood
design and ventilation rate must be consistent with American Conference
of Governmental Industrial Hygienists recommended practices. 40 CFR
63.1543(b). In addition, the sinter machine area fugitives must be
enclosed in a building that is ventilated to a baghouse at a rate that
maintains a positive in-draft through any doorway opening. 40 CFR
63.1543(c). The MACT standard also requires the use of bag leak
detection systems for continuous monitoring of baghouses. 40 CFR
63.1547(c)(9). For fugitive dust sources, as defined in 40 CFR 63.1544,
the MACT standard requires that the owner or operator prepare and
operate at all times according to a standard operating procedures (SOP)
manual. The SOP manual must describe in detail the measures used to
control fugitive dust emissions from plant roadways, material storage
and handling areas, sinter machine areas, blast and dross furnace
areas, and refining and casting operations areas. Existing work
practice manual(s) that describe the measures in place to control
fugitive dust sources required as part of a state implementation plan
for lead satisfy this requirement.
2. MACT as it Applies to Doe Run Company Primary Lead Smelter,
Herculaneum, Missouri
As stated above, the Doe Run Smelter in Herculaneum, Missouri, is
the sole remaining lead processing facility in the United States
subject to the MACT. The 1999 MACT rule established a plant-wide lead
emission limit of 1 lb of lead per ton of lead produced that applies to
the aggregation of emissions from specific sources that discharge from
air pollution control devices. Compliance with the plant-wide emission
limit is demonstrated by annual stack testing. The rule lists nine
sources as subject to the plant-wide limit including: (1) Sinter
machine, (2) blast furnace, (3) dross furnace, (4) dross furnace
charging location, (5) blast furnace and dross furnace tapping
location, (6) sinter machine charging location, (7) sinter machine
discharge end, (8) sinter crushing and sizing equipment, and (9) sinter
machine area. At the Doe Run plant, lead emissions from these sources
are controlled by baghouses that exhaust through two stacks. The
sources in the sinter operation, the blast furnace, and the dross
furnace are controlled by three baghouses all of which discharge
through one emission point, which is designated as the main stack. The
building that houses the blast furnace and dross kettles is vented to a
separate baghouse (7) which discharges through a separate
stack, designated as the furnace area stack.
Under the 1999 MACT rule, all other sources of process fugitive and
fugitive dust emissions are required to follow work practice standards
detailed in the plant's standard operating procedures (SOP) manual.
The HAP emitted in the largest quantities from the Doe Run facility
are
[[Page 9427]]
lead compounds, which account for over 99 percent of the total HAP
emissions by mass. The remaining HAP emissions are arsenic, antimony,
cadmium, cobalt, nickel and trace organic HAP. Negligible levels of
organic HAP are also emitted from natural gas-fired space heating at
the facility and the incomplete combustion of coke in the blast
furnace. Further discussions of the emission profile for this facility
is included in the Technical Support Document in the docket.
3. Missouri SIP and the Lead NAAQS as They Apply to Doe Run Company,
Herculaneum, Missouri
In addition to the MACT standard, the Doe Run Company's primary
lead smelter in Herculaneum, Missouri is subject to a SIP for the
purpose of attaining and maintaining the lead NAAQS.\17\ The current
SIP, which was approved in 2002, addresses the former lead ambient air
concentration limit of 1.5 [mu]g/m\3\ NAAQS. In addition, the 2007 SIP
submittal from the State includes requirements addressing lead
emissions from the Doe Run facility and can be found at http://www.dnr.mo.gov/env/apcp/docs/2009drh-leadsip.pdf.
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\17\ EPA most recently approved the Missouri SIP for Herculaneum
in 2002 (67 FR 18497, April 16, 2002). Missouri Department of
Natural Resources (MDNR) substantially revised the requirements for
the smelter in 2007. EPA has proposed approval of this revision, but
has not yet taken final action.
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In 2008, EPA revised the lead NAAQS from 1.5 [mu]g/m\3\ to 0.15
[mu]g/m\3\. In November 2010, EPA identified or ``designated'' several
areas as not meeting the lead NAAQS. These ``nonattainment''
designations include portions of Jefferson County, Missouri surrounding
the Doe Run facility. Missouri is required by the Act to take steps to
further control pollution in this area, and to detail these steps in a
revision to the SIP. The revised SIP is due to EPA within eighteen
months after the effective date of the designation, or by June 2012,
and attainment of the NAAQS should be achieved by 2016.
The SIP and the pending 2007 SIP submittal contain specific
measures to be implemented by the Doe Run plant to reduce lead
emissions. The State of Missouri revised the control requirements for
the Doe Run facility in 2001 and 2007, requiring numerous emissions-
reducing measures and improvements to add-on control devices,
processes, and work practices.\18\ These included improvements to
existing emission control technology, adding or upgrading enclosures,
process changes and limitations, and work practices. These requirements
are summarized below.
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\18\ EPA most recently approved the Missouri SIP for Herculaneum
in 2002 (67 FR 18497, April 16, 2002). MDNR substantially revised
the requirements for the smelter in 2007. EPA has proposed approval
of this revision, but has not yet taken final action.
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Point Source Requirements--As required under the SIP, lead
emissions from the refining kettles and refining building emissions
must be captured and vented to baghouses. Doe Run implemented these
controls and vents the emissions to baghouses 8 and 9
and the exhaust from the baghouse 9 is combined with baghouse
7 exhaust and vented to a common stack. Although the MACT
standard does not require Doe Run to do so, it has included emissions
from refining Baghouses 8 and 9 in their
demonstrations of compliance with the MACT plant-wide lead emission
limit.
Under the 2007 SIP submittal, Doe Run was required to make
improvements to existing baghouse controls including the installation
of pleated filters and lowering the air-to-cloth ratio for baghouses,
increased ventilation and improved ventilation hoods at the blast
furnace, and using reverse flow technology for baghouse cleaning. The
2007 SIP submittal also required the installation of enclosures and/or
partial enclosures for unloading ore concentrate, sinter storage, and
the sides of the sinter machine (which will be evacuated to a
baghouse).
Process Requirements--Process changes to reduce emissions required
by the SIP included a process control system for the injection of air
through the blast furnace tuyeres located at the bottom of the blast
furnace, limitations on individual process and overall plant
throughputs, and limiting specific operations to only certain times of
the day when the impact on ambient air concentrations is less. The SIP
also stipulates that emissions from malfunctions will be reduced by
alarms that sound when the baghouse fan malfunctions, an interlock
system to restrict air flow into the blast furnace when the baghouse is
not operating properly, and cameras for the dross and refinery kettles
to detect kettle failure (i.e., when a plume of smoke is detected from
the stack, the kettle burner can be immediately shut off and the
problem corrected).
Fugitive Dust Requirements--Under both the current SIP and the 2007
SIP submittal, work practices are required to reduce fugitive dust
emissions. Requirements include road watering and automatic sprinklers,
using new regenerative sweepers to remove dust from paved surfaces to
reduce emissions from traffic, maintaining a minimum water content
percentage for ore concentrate and for baghouse dust that is loaded
into railcars, and inspecting the siding that encloses buildings
(followed by prompt repairs if needed).
Missouri requires Doe Run to report all metal HAP emissions
annually based on a speciation analysis that was performed.\19\ The
state also requires an annual emissions inventory based on the stack
tests for the point discharges and AP-42 or facility-specific emission
factors for fugitive emissions.
---------------------------------------------------------------------------
\19\ Doe Run Company submits annual emissions inventories to
MDNR that report speciated metals using speciation factors for each
metal/source derived in the late 1990s through emissions testing.
---------------------------------------------------------------------------
As a result of the implementation of the emission control
requirements in the currently approved 2002 SIP, and the additional
requirements adopted by the state, as discussed above, the Doe Run
facility has achieved a significant reduction of lead and metal HAP
emissions since 2000 through a combination of reduced production levels
and improved emissions controls. Based on emissions inventory data
submitted to the Missouri Department of Natural Resources (DNR), total
HAP emissions have been reduced from an estimated 140 tons in 2000 to
20 tons in 2008, and the majority of the 20 tons are lead compound
emissions. The 2008 reported emissions reflect implementation of all
emission controls stipulated in the 2002 SIP and the 2007 SIP revision.
4. Other Federal and State Actions Affecting Doe Run Company
More recently, the 2008 revision to the lead NAAQS has resulted in
Doe Run Company deciding that it is not feasible for the facility to
reduce emissions further to the level necessary to meet the newly
revised NAAQS without closure of the current smelting operations. As a
result of past and ongoing regulatory compliance issues at the
facility, the facility has entered into a consent decree with U.S. EPA
Region VII and the State of Missouri. Under the consent decree, the
facility will, among other things, close the existing smelter operation
and remediate the site to an agreed-upon level. The consent decree
requires that all support operations for the smelter cease by December
31, 2013 and that the blast furnace cease operations by April 1, 2014.
Remediation of the site is required to commence following approval of a
plan to be submitted to EPA in January 2013. Under the consent decree,
the existing refining, casting and alloying operations
[[Page 9428]]
will be allowed to continue operation. Notice of the consent decree was
published for public comment on October 15, 2010, (75 FR 63506). Once
finalized, the consent decree is federally enforceable among the
parties.
Prior to closure of the current smelter, the Doe Run Company may
build and bring to full operation a new hydrometallurgical process that
will produce lead from lead sulfide ore, potentially adjacent to the
current smelter. The hydrometallurgical process uses chemical reactions
involving fluboric acid which allows recovery of lead metal through
leaching, electrowinning, and co-product treatment processes. Some of
the lead from the new process is likely to undergo further processing
at the existing refinery, primarily for remelting/casting purposes.
Based on limited data from a demonstration project, Doe Run expects
that lead emissions from the hydrometallurgical process will be
minimal.
V. Analyses Results and Proposed Decisions
This section of the preamble provides a description of the dataset
used in the RTR analysis, the results of our RTR for the source
category, and our proposed decisions concerning changes to the Primary
Lead Smelting MACT standard. As noted previously, all references to
lead emissions in this proposal means ``lead compounds,'' which is the
regulated HAP under CAA section 112. All reference to lead production
means the production of element lead.
A. What data were used in our risk analyses?
For the Primary Lead Smelting source category, we compiled a
preliminary dataset using readily available information, reviewed the
data, and made changes where necessary. The preliminary dataset was
based on data in the 2002 National Emissions Inventory (NEI) Final
Inventory, Version 1 (made publicly available on February 26, 2006),
and the 2005 National Emissions Inventory (NEI), version 2.0 (made
publicly available in October 2008). The 2005 NEI was updated to
develop the 2005 National Air Toxics Assessment (NATA) Inventory. NATA
inventory updates for the primary lead smelting category included SIP
data provided by the state of MO to EPA. The 2005 NATA inventory was
used with updated 2008 data received in an Information Collection
Request (ICR) response from the Doe Run facility. The NEI is a database
that contains information about sources that emit criteria air
pollutants, their precursors, and HAP. The NEI database includes
estimates of annual air pollutant emissions from point and volume
sources, emission release characteristic data such as emission release
height, temperature, velocity, and location latitude/longitude
coordinates. We reviewed the NEI datasets, checked geographic
coordinates, and made changes based on available information. We also
reviewed the emissions and other data to identify data anomalies that
could affect risk estimates.
The risk assessment was based on estimates of the actual emissions
and allowable emissions. The estimates of actual emissions were for the
year 2008 and were based on data from the ICR along with data from our
NEI dataset. These estimates included both stack and fugitive emission
sources. Fugitive dust sources include material handling (concentrate,
sinter, fume and dross), plantwide resuspension (roadways, storage
piles and plant yard) and other miscellaneous sources (vents and heat
stacks). The material handling sources contribute approximately 84
percent of the total fugitive dust emissions, while plantwide
resuspension and miscellaneous sources contribute approximately 11 and
5 percent, respectively. The estimates of allowable emissions were
calculated using production data from the ICR response combined with
the current emissions limits in the MACT standard.
Lead compounds account for about 99 percent of the HAP emissions
from the source category, or about 20 tons in 2008. The facility also
reported small emissions of five other metal HAP, and trace levels of
25 organic HAP.
The emissions data, calculations and risk assessment inputs for the
Primary Lead Smelting source category are described further in the
Technical Support Document for this action which is available in the
docket for this proposed rulemaking.
We used the 2008 production information as the basis for
calculating the MACT allowable ratio (allowable to actual) because the
2008 emissions are the most recent reported emissions that also reflect
implementation of the requirements of the 2007 SIP revision. For more
information on the ratio of actual to MACT-allowable emissions, see the
Technical Support Document in the docket for this action describing the
emission data information and estimation of MACT-allowable emission
levels and associated risks and impacts.
B. What are the results of the risk assessments and analyses?
For the Primary Lead Smelting source category, we conducted an
inhalation risk assessment for all HAP emitted. We also conducted a
multi-pathway analysis for cadmium and lead. With respect to lead, we
used the recently-promulgated lead NAAQS to evaluate the potential for
multi-pathway and environmental effects. Furthermore, we conducted a
demographic analysis of population risks. Details of the risk
assessments and additional analyses can be found in the residual risk
documentation referenced in section IV.A of this preamble, which is
available in the docket for this action.
1. Inhalation Risk Assessment Results
Table 3 provides an overall summary of the results of the
inhalation risk assessment.
Table 3--Primary Lead Smelting Inhalation Risk Assessment Results
--------------------------------------------------------------------------------------------------------------------------------------------------------
Maximum individual cancer risk (in 1 Maximum chronic non-cancer TOSHI \2\
million) \1\ Estimated Estimated annual -------------------------------------------- Maximum off-site
------------------------------------------- population at risk cancer incidence refined acute non-
Actual emissions Allowable emissions >= 1-in-1 million (cases per year) Actual emissions Allowable emissions cancer HQ \3\
level level level level
--------------------------------------------------------------------------------------------------------------------------------------------------------
30 30 4,900 0.0008 1 1 0.6
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Estimated maximum individual excess lifetime cancer risk.
\2\ Maximum TOSHI. The target organ with the highest TOSHI for the Primary Lead Smelting source category is the kidney.
\3\ The maximum acute HQ value shown uses the only available acute dose-response value for arsenic, which is the REL. See section IV.A of this preamble
for explanation of acute dose-response values.
[[Page 9429]]
The results of the chronic inhalation cancer risk assessment
indicate that, based on estimates of actual emissions from the base
year 2008, the maximum individual lifetime cancer risk could be as high
as 30-in-1 million with fugitive dust emissions of cadmium dominating
the risk. The total estimated cancer incidence from this source
category based on actual emission levels is 0.0008 excess cancer cases
per year or one case in every 1,250 years. Approximately 200 people
were estimated to have cancer risks above 10-in-1 million and
approximately 4,900 people were estimated to have cancer risks above 1-
in-1 million. When considering the maximum levels of emissions allowed
under the current MACT standard, the MIR remains 30-in-1 million. The
MIR remains the same since the fugitive dust emissions are governed by
work practices, which under Sec. 63.1544 are defined as the measures
that will be ``put into place to control fugitive dust emissions.''
Thus, the actual emissions, which reflect the measures that have been
put in place, should be equivalent to the allowable emissions.
The maximum chronic noncancer TOSHI value is 1, with fugitive
emissions of cadmium dominating those impacts. When considering MACT
allowable emissions, the maximum chronic noncancer TOSHI value remains
1 since, for the reasons provided above, MACT-allowable fugitive
emissions are equal to actual fugitive emissions.
Based on the acute REL value for arsenic, an off-site screening-
level acute HQ value from this facility could be as high as 6. However,
the emissions factor of 10 times the average hourly emissions rate is
not appropriate in this instance, given that fugitive emissions are
minimized during the meteorological conditions associated with the
worst-case short-term impacts (i.e., during low-wind, stable
atmospheric conditions). Thus, we refined the assessment and estimated
a maximum off-site HQ value of 0.6.
The results of a multipathway screening analysis for cadmium
emissions from this facility were well below the de minimis emission
rate that would indicate a non-negligible risk of adverse health
effects from multipathway exposures. We estimate the specific
multipathway de minimis emission rate for cadmium to be 0.65 TPY and
only 0.1 TPY is emitted from the one facility in this source category.
Thus, there appears to be little, if any, multipathway risk associated
with cadmium emissions from this facility.
In evaluating the potential multi-pathway risks from emissions of
lead compounds, we compared modeled maximum 3-month rolling average
atmospheric concentrations with the NAAQS for lead. Table 4 presents
the results of our lead impact analysis broken down by emission point
considering actual 2008 emissions as well as the maximum emissions of
lead that the MACT standard would have allowed based on production
rates for calendar year 2008. For purposes of our analysis, we
determined separately the risk from each of the types or processes/
emissions sources regulated by the current MACT, with one exception.
Under the MACT, emissions from the refining and casting area were
considered fugitive emissions subject to work practice standards under
Sec. 63.1544. Since then, pursuant to requirements that the 2002 State
SIP adopted for purposes of meeting the 1.50 [mu]g/m\3\ lead NAAQS, Doe
Run enclosed the refining and casting area and vents those emissions to
the refinery stacks. We considered these stack emissions separate from
the fugitive dust emissions. Thus, the four emission process/sources we
evaluated for risk were: (1) The main stack, (2) the furnace area
stack, (3) the refinery stack, and (4) fugitive emissions.
The analysis indicates that under both actual 2008 or MACT
allowable emission scenarios, emissions from the main stack do not
result in lead levels above the NAAQS within the 50 km radius that was
modeled. This is likely due to the height of the stack (500 feet),
which would result in broader and further dispersal of lead emissions.
However, results of the analysis did indicate that modeled ambient air
lead concentrations resulting from this facility's fugitive dust
emissions could exceed the NAAQS for lead by as much as 50-fold at the
property boundary based on both actual and allowable emissions.
Moreover, results indicate that modeled emissions from the furnace area
stack could result in NAAQS exceedances under both actual 2008 and
MACT-allowable emissions scenarios. In addition, the actual estimated
emissions from the refining stacks, which were put into place based on
requirements adopted by the State for purposes of the SIP, could result
in NAAQS exceedances. We were unable to calculate a ``MACT allowable''
emission level for the refinery emissions, which under the MACT are
included as fugitive emissions. This analysis also indicates that
within 50 km of this facility, approximately 1,900 people could be
exposed to ambient air lead concentrations exceeding the level of the
NAAQS for lead.
As mentioned above, to evaluate the potential for adverse
environmental effects, we also compared maximum 3-month rolling average
atmospheric concentrations with the current secondary NAAQS for lead,
which is the same as the primary standard. Thus, the analyses presented
in Table 4 also indicate the potential for adverse environmental
effects from emissions of lead. Note that modeling performed for this
analysis is based on different inputs than SIP modeling done for the
one remaining primary lead facility, and thus results differ.
Table 4--Summary of Modeled Lead Concentrations Relative to the NAAQS Based on Estimated Actual 2008 and MACT
Allowable Emissions
----------------------------------------------------------------------------------------------------------------
Actual
2008 Maximum impact-- Allowable Maximum impact-- allowable
Emission point emissions actual emissions emissions emissions
(TPY) \1\ (TPY)
----------------------------------------------------------------------------------------------------------------
Main stack \2\.................. 13.31 0.05 times the 65.8 0.25 times the NAAQS.
NAAQS.
Refining stacks................. 2.74 3 times the NAAQS.. NA NA.
Furnace area stack: (controlled 1.81 2 times the NAAQS.. 8.94 10 times the NAAQS.
blast and drossing fugitives).
Fugitive dust \3\............... 2.85 50 times the NAAQS. 2.85 50 times the NAAQS.
----------------------------------------------------------------------------------------------------------------
\1\ Allowable emissions for the main stack and furnace area emission points are based on 1 lb of Pb/ton
production (MACT limit); Refinery emissions are included as fugitive emissions under MACT but are now vented
to a stack because of SIP requirements; therefore, we were unable to calculate a ``MACT allowable'' emission
level.
\2\ Main stack is the emission point for sinter machine, blast furnace and drossing operations.
[[Page 9430]]
\3\ Fugitive dust emissions are covered by work practices under current MACT and were calculated via emission
factors assuming compliance with the MACT. The site of maximum ambient air lead concentration resulting from
fugitive dust emissions occurs in close proximity to the southeast boundary of the facility (see Figure 3.1-1
of the risk assessment document). Note that this maximum result and its location are based on modeling 2008
emissions using 1998 site-specific meteorology, and that these may differ from inputs used for other types of
modeling (e.g., SIP modeling.)
2. Facility-wide Risk Assessment Results
Our screening analysis determined that the organic HAP emissions
from facility represented negligible risk and were determined to be
insignificant with regard to this risk analysis. As a result, all
significant HAP emissions from the one facility in this category are
reflected in the risk analyses presented above; therefore, facility-
wide risks are equivalent to those of the source category.
3. Model to Monitor Comparison
In addition to the results presented above, we also compared
maximum AERMOD estimates of ambient air lead concentrations with those
measured at 4 monitors in close proximity to the Herculaneum Primary
Lead Smelting Facility for calendar year 2008. More specifically, we
compared maximum 3-month rolling average lead concentrations (for
calendar year 2008) calculated from data reported at the Main Street,
Circle Street, South Cross, and Church Street monitors to the maximum
3-month rolling average lead concentrations at model receptor locations
in close proximity to these monitoring sites. These monitor locations
were chosen because they represented the closest offsite monitors to
the Herculaneum primary lead smelter. Thus, lead measurements at these
monitoring sites would likely be dominated by emissions from this
facility which is important given that AERMOD estimates of ambient air
lead concentrations only considered lead emissions from this facility
(i.e., only lead emissions from the Herculaneum primary lead smelter
were used as inputs into AERMOD).
Results of this analysis are presented in Table 5 and indicate that
with respect to the Main Street and Circle Street monitors, AERMOD
underestimates 3-month maximum lead concentrations by approximately
2.8- and 4.2-fold, respectively. While these monitor to model
comparisons are not in complete agreement on a point-by-point basis, we
note that this would not be expected given the general uncertainties
associated with using dispersion modeling to estimate ambient pollutant
concentrations and considering that the meteorological data used to
develop the model estimates were from a different year than the actual
monitoring and emissions data (i.e., meteorological data used in the
AERMOD simulation was from 1998 while the emissions estimates and the
monitoring data were from 2008). However, results do indicate that the
maximum 3-month average lead concentration across the group of monitors
nearest the facility is approximately equal to the maximum 3-month
average lead concentration estimated by AERMOD across the group of
these monitoring sites (i.e., both the Main Street monitor and the
South Cross AERMOD estimate indicate the maximum 3-month average lead
concentration to be approximately 2.1 [micro]g/m3). Taken together,
these results indicate that AERMOD estimates of ambient air lead
concentration provide a reasonable representation of the measured 3-
month maximum lead concentrations present in the ambient air near this
facility.
---------------------------------------------------------------------------
\20\ Maximum 3-month monitored concentrations were calculated
for the year 2008 based on data submitted to EPA's Air Quality
System (AQS).
\21\ Negative sign denotes an underestimation of AERMOD modeled
ambient lead concentrations, relative to monitored concentrations.
AERMOD estimated concentrations were based on the 2008 emissions
estimates described in section V.A.
Table 5--Comparison of AERMOD Modeled to Ambient Air Lead Concentrations Reported by Four Monitors Surrounding
the Herculaneum Primary Lead Smelting Facility
----------------------------------------------------------------------------------------------------------------
Maximum AEMOD Maximum monitored 3-
modeled 3-month month lead Model to
Location lead concentration concentration \20\ monitor ratio
([mu]g/m\3\) ([mu]g/m\3\) \21\
----------------------------------------------------------------------------------------------------------------
Main Street.......................................... 0.47 3.14 -4.6
Circle Street........................................ 0.38 1.14 -3.0
South Cross.......................................... 2.13 0.75 2.8
Church Street........................................ 1.99 0.47 4.2
----------------------------------------------------------------------------------------------------------------
4. Demographic Risk Analysis Results
Demographic analyses were performed to investigate the population
distribution of: (1) Cancer risks at or above 1-in-1 million and (2)
risks from ambient air lead concentrations above the NAAQS for lead.
Results are summarized in Table 5 and are based on modeling using
estimated actual emissions levels for the population living within 50
km of this facility.
Table 6--Primary Lead Smelting Demographic Risk Analysis Results
----------------------------------------------------------------------------------------------------------------
Population with
Population with ambient air lead
Nationwide cancer risk concentrations
greater than 1 in exceeding the
a million NAAQS
----------------------------------------------------------------------------------------------------------------
Total population....................................... 285,000,000 4,900 1,900
----------------------------------------------------------------------------------------------------------------
Race by percent
----------------------------------------------------------------------------------------------------------------
White.................................................. 75 96 96
[[Page 9431]]
All Other Races........................................ 25 4 4
----------------------------------------------------------------------------------------------------------------
Race by percent
----------------------------------------------------------------------------------------------------------------
White.................................................. 75 96 96
African American....................................... 12 4 3
Native American........................................ 0.9 0.2 0
Other and Multiracial.................................. 12 1 0.8
----------------------------------------------------------------------------------------------------------------
Ethnicity by percent
----------------------------------------------------------------------------------------------------------------
Hispanic............................................... 14 1 0.3
Non-Hispanic........................................... 86 99 99.7
----------------------------------------------------------------------------------------------------------------
Income by percent
----------------------------------------------------------------------------------------------------------------
Below poverty level.................................... 13 15 15
Above poverty level.................................... 87 85 85
----------------------------------------------------------------------------------------------------------------
Results of the risk assessment indicate that there are
approximately 4,900 people exposed to a cancer risk greater than 1-in-1
million, and 1,900 people in areas with ambient air lead concentrations
above the NAAQS for lead. In both instances, the demographics analysis
estimates that about 4 percent of these populations can be classified
as a minority (listed as ``all Other Races'' in the table), which is
well below the national percentage of 25. Similarly, in the cancer and
lead demographic analyses, the percentage of ``African American,''
``Hispanic,'' ``Native American,'' and ``Other and Multiracial''
population groups are well below the corresponding national
percentages. With respect to the percentage of those ``Below the
Poverty Level,'' in both demographic analyses there is a small (2
percent) increment above the corresponding national percentage.
However, given that the total population affected is small (i.e., 4,900
individuals for cancer risk greater than 1-in-1 million and 1,900
individuals in areas with lead concentrations above the NAAQS), we do
not think this indicates any significant potential for disparate
impacts to the specific demographic groups analyzed.
Moreover, given the extent to which lead may impact children's
health, we further note that our demographic analysis doesn't indicate
the presence of a higher percentage of children than one would normally
expect around this facility. That is, while the national percentage of
children 18 years and younger is 27%, the percentage of children living
near this facility who are estimated to be exposed to lead
concentrations above the NAAQS is only slightly higher at 28% (see Risk
and Technology Review--Analysis of Socio-Economic Factors for
Populations Living Near Primary Lead Smelting Facilities in the docket
for this proposed rulemaking), a difference which is likely not
significant.
C. What are our proposed decisions on risk acceptability and ample
margin of safety?
1. Risk Acceptability
As noted in section III.B of this preamble, we weigh all health
risk factors in our risk acceptability determination, including cancer
risks to the individual most exposed, risk estimation uncertainty, and
other health information. For the Primary Lead Smelting source
category, the risk analysis indicates that the cancer risks to the
individual most exposed could be as high as 30-in-1 million due to
actual or MACT-allowable emissions. These risks are considerably less
than 100-in-1 million, which is the upper bound of the presumptive
range of acceptability. The incidence of cancer is very low--0.0008
excess cancer cases per year; or one case every 1,250 years. Similarly,
the risks of chronic non-cancer health effects from HAP emissions other
than lead were low, with a maximum HQ of 1. Moreover, while an initial
screening analysis suggested that fugitive emissions of arsenic had the
potential to create a risk of acute health effects, a refined analysis
based on our knowledge of this emission source indicated that the risk
was low (HQ = 0.6). In addition to these health analyses, a
demographics analysis did not indicate the potential for significantly
disproportionate heath impacts (see above, section V(3)(c)). Thus,
risks associated with the non-lead emissions from the Primary Lead
Smelting source category for cancer, acute and chronic non-cancer
health effects and environmental effects are considered acceptable.
However, since ambient air lead concentrations resulting from
emissions from this facility were modeled to be in excess of the NAAQS
for lead, the risks associated with lead emissions from this facility
were judged to be significant. Our analysis estimated that modeled off-
site ambient air lead concentrations (based on actual 2008 emissions)
resulting from this facility could be as high as 50 times the NAAQS for
lead based on fugitive dust emissions, and that approximately 1,900
individuals could be exposed to lead concentrations in excess of the
NAAQS. Given that the NAAQS for lead was set to ``provide increased
protection for children and other at-risk populations against an array
of adverse health effects, most notably including neurological effects
in children, including neurocognitive and neurobehavioral effects (73
FR 67007)'', we are proposing that risks associated with lead emissions
from this source category are unacceptable.
As noted above, our risk analysis for lead was based on modeled 3-
month rolling average lead concentrations in ambient air in comparison
to the primary lead NAAQS. We believe that in order to provide an
acceptable level of risk, lead concentrations in the ambient air must
be reduced to the level of the lead NAAQS. Thus, we
[[Page 9432]]
considered specific emission limits for the three emission sources/
points that were modeled to result in lead concentrations in excess of
the NAAQS (see Table 4); refinery stack, furnace area stack, and
fugitive dust emissions, with the majority of fugitive dust impacts
from material handling sources. Based on our analysis, we conclude that
in order to meet the NAAQS for lead at all model receptors, fugitive
dust emissions would have to be reduced by approximately 98 percent to
0.064 TPY, refinery stack emissions and furnace area stack emissions
would have to be reduced by approximately 80 percent to a total of 0.91
TPY (the maximum impacts of refinery and furnace emission points occur
at the same location.) Further, because the maximum ambient air impacts
of the refinery/furnace emissions, the fugitive dust emissions, and the
main stack do not significantly overlap each other, we estimate that
lead emissions from all emission points other than the main stack would
have to be limited to a total of approximately 0.97 TPY in order to
ensure 3-month rolling average ambient air lead concentrations do not
exceed the lead NAAQS level of 0.15 [mu]g/m\3\. As noted above,
emissions from the main stack (i.e., emission point for sinter machine,
blast furnace and drossing operations) did not result in ambient air
lead concentrations in excess of the lead NAAQS at modeled locations
within 50 km of the property boundary and thus we are not proposing any
reductions at the main stack in order to ensure an acceptable level or
risk.
Once we determined the emissions reductions necessary to achieve an
acceptable level of risk, we investigated available emissions control
options and their ability to reduce emissions and health risks for
fugitive dust and for stack emissions from both the refining and
furnace area stacks. Control options considered for reducing fugitive
dust emissions and associated risks include improved or additional work
practices, site remediation, application of additional capture/control
measures, and lead production limitations. With the exception of site
remediation, all of these control measures have been implemented to
varying degrees at the Doe Run facility in response to the Missouri
SIP, as revised in 2002 and the 2007 revisions submitted for approval
to the SIP. As such, because the actual emissions for 2008 reflect the
implementation of those control measures, requiring those controls
under the MACT would be unlikely to yield the additional 98 percent
reduction in fugitive emissions necessary to meet the primary lead
NAAQS level of 0.15 [micro]g/m \3\. Thus, our evaluation of risks based
on actual emissions already considered emissions with these controls
largely in place. In order to ensure that site remediation efforts, or
any other efforts the source may choose to undertake, will result in
sufficient emission reductions to address the unacceptable level of
risk, we are proposing to establish a lead concentration in air limit
of 0.15 [micro]g/m \3\ to be measured at locations approved by the
Administrator. This lead concentration in air limit would be
established as the enforceable requirement to address fugitive
emissions under the MACT standard.\22\ Because we are proposing a
concentration limit to address fugitive dust emissions, we no longer
believe it is necessary for the affected facility to provide a plan to
the Administrator describing work practices that will be used to reduce
fugitive emissions. Therefore, we are proposing to remove the
requirement to develop and submit a work practice standard operating
procedure (SOP) manual as required in Sec. 63.1544(a).
---------------------------------------------------------------------------
\22\ Under the consent decree, of which we sought public comment
last fall, fugitive dust sources will be addressed by site
remediation; however, some fugitive dust emissions will remain
during the remediation of the site, which will likely extend beyond
April 2014.
---------------------------------------------------------------------------
As an alternative to proposing compliance monitoring requirements
for demonstration of compliance with the lead concentration in air
limit, we considered retaining the current fugitive dust emissions
requirement to develop and submit to the Administrator or delegated
authority a work practices SOP. Using this alternative approach, we
believe it would be necessary to modify the current general
requirements for an SOP by specifying the minimum work practice
requirements that the plan must include. For example, under this
alternative approach, we would require that the SOP must include, at a
minimum, detailed descriptions of all measures that would be used to
control fugitive dust emissions from plant roadways; material storage,
transfer and handling areas; sinter machine areas; furnace areas;
refining and casting areas; and other areas the Administrator may
identify. Further, EPA would require that the SOP contain detailed
descriptions of work practices including road watering and automatic
sprinklers, methods to remove dust from paved surfaces to reduce
emissions from traffic, maintenance of minimum water content for ore
concentrate and for baghouse dust that will be handled or transferred,
and procedures for the inspection of building siding or damages and
openings. The SOP would be required to include procedures, including
recordkeeping, to ensure that the work practices are being implemented
at a frequency and in a manner that would ensure that fugitive dust
emissions are being minimized. To determine whether the work practices
described in the SOP are reducing emissions sufficient to comply with
the lead concentration in air limit, the owner or operator would be
required once a year to model the fugitive dust emissions using
measurement data or emission factors according to an approved fugitive
dust emissions modeling plan. At a minimum, EPA would require that this
modeling plan include a detailed description of each fugitive dust
emission source; a detailed description of the control practices or
techniques used to limit fugitive dust emissions from each source; the
emission factors, test data or other methods used to characterize and
quantify lead emissions from each source; a description of the
emissions modeling that will be used to estimate the concentrations of
lead in air at or near the property boundary as contributed by each
source as well as cumulatively contributed by all sources; a
description of process or other conditions that would indicate the need
to demonstrate compliance more often than annually; the calculations to
be used to show compliance with the air lead concentration limit that
consider the highest modeled air lead concentrations from the modeled
fugitive dust sources and any contributions from background lead
concentrations in air; and a description of the records that will be
kept. We are seeking comments on the proposed requirements to monitor
air lead concentrations versus the alternative approach described
above, of requiring extensive work practices and a work practice SOP in
conjunction with emissions modeling, to demonstrate compliance with the
air lead concentration limit.
Measures available for reducing lead emissions from the refining
and furnace area stacks include upgrading existing baghouses by
replacing the existing fabric bags with high efficiency membrane bag
filters. Another option would be to add extra in-line baghouses after
existing baghouses. Such measures would reduce lead emissions and
associated risk to within acceptable levels.
In summary, our analysis indicates that in order to ensure that
lead emissions from this source do not pose an unacceptable risk,
emissions from
[[Page 9433]]
this facility would need to be reduced to a level that would ensure
that these emissions would not result in air lead levels greater than
the 0.15 [micro]g/m \3\ for any 3-month period at all of the modeled
locations. Further, we conclude that in order to achieve the 0.15
[micro]g/m \3\ level (for any 3-month rolling average) at all modeled
locations, fugitive dust emissions would need to be reduced by 98
percent and the emissions from the furnace area and refining operation
stacks would need to be reduced by 80 percent. We have identified
emission reduction and control options for achieving the required
reductions, which include implementation of site remediation, work
practices, and upgrade of existing baghouses with membrane bags and/or
addition of an additional in-series baghouse.
We are proposing the following requirements to ensure that risk is
reduced to an acceptable level.
A stack lead emission cap of 0.91 TPY that would apply to
the furnace area stack and the refining operation stacks.
An air lead concentration limit of 0.15 [micro]g/m\3\
based on 3-month rolling average (to be measured at locations approved
by the Administrator) to ensure that fugitive dust emission levels will
not exceed the NAAQS.
The proposed limits apply to both new and existing facilities. Any
facility subject to the MACT would be required to meet these
requirements for each emission unit it is operating that is subject to
the limit. In order to address any fugitive dust emissions, the
facility, regardless of whether it is operating all or just some of the
emission sources covered by this action, would be required to meet the
air lead concentration emission limit.
For both new and existing facilities, compliance with the air lead
concentration limit would be demonstrated using lead compliance
monitoring devices and would be based on a rolling 3-month average
concentration. The proposed rule requires development of a monitoring
plan for approval by the Administrator that includes the minimum
sampling and analysis methods and compliance demonstration criteria
provided in the rule. A provision is included in this proposed rule
that allows for reduced monitoring if the facility demonstrates an air
lead concentration for three consecutive years at less than 50 percent
of the air lead concentration limit. The monitoring can be reduced to
once every six months unless one of the 6-month monitoring events
exceeds 50 percent of the air lead concentration limit, at which time
monitoring will be required to resume based on the initial plan
approved by the Administrator until another three years of consecutive
monitoring below 50 percent of the air lead concentration limit is
achieved. The compliance requirements discussed above were designed to
allow for flexibility, prevention of redundant requirements, and also
to provide consistency with current monitoring required at the site. We
are soliciting comment on this approach. For existing facilities,
compliance with the emission limit for the furnace area and refinery
stacks would be demonstrated through stack testing conducted on a
quarterly basis. All performance testing will be consistent with the
existing MACT testing requirements, with the exception of frequency. As
provided in Sec. 63.153(e) of the current rule, the facility can
reduce compliance testing frequency if the most recent three compliance
tests demonstrated compliance. We are maintaining this provision,
however, because this proposed rule increases the testing frequency to
quarterly, the number of most recent tests necessary to comply with
this provision will be increased from three to 12. New primary lead
processing facilities would be required to demonstrate compliance using
a lead continuous emission monitoring systems (CEMS). However, since
the Agency has not finalized the performance specification for the use
of these instruments, we are deferring the effective date of the
requirement to install, correlate, maintain and operate lead CEMS until
these actions can be completed. The lead CEMS installation deadline
will be established through future rulemaking, along with other
pertinent requirements. In the event operations commence at a new
facility prior to promulgation of the performance specification,
compliance would be demonstrated through quarterly stack testing until
promulgation of the lead CEMS performance specification.
2. Ample Margin of Safety
Reducing lead emissions to meet the NAAQS would ensure that
emissions of all HAP do not pose an unacceptable risk. Once we ensure
that the risk is acceptable, we then look to determine whether further
reductions are appropriate to ensure an ample margin of safety. In this
part of our analysis, we again consider the health factors we
considered to determine whether the risks are acceptable but we also
consider the cost of controls.
With regard to lead emissions, we are proposing to require most of
the emission sources at the facility to implement all technically
feasible controls in order to ensure that the ambient air meets the
level of the lead NAAQS, which is the level that we have determined
will ensure an acceptable level of risk. Because all feasible controls
will need to be adopted in order to meet that proposed standard, there
are no additional controls to consider for the three emission sources:
Fugitive dust emissions, the furnace area stack, and the refinery
stacks. We further note that the same controls we have proposed for the
three emission points to reduce lead emissions are the same controls
that would reduce risks from cadmium and all other metal HAP known to
be emitted from this source category. Thus, we are proposing that the
controls required to ensure that risk from lead emissions from those
three emission points is acceptable also protect public health with an
ample margin of safety with regard to emissions from all metal HAP from
these three emission points. Notably, after these standards are in
place, we estimate that the MIR cancer risk due to the non-lead HAP
will be less than 1-in-1 million.
Our risk analysis indicates that the main stack emissions do not
result in ambient air lead levels exceeding the NAAQS based on either
actual or allowable emission levels. We determined, as discussed
section V.D. below, that it is technologically feasible to reduce
emissions from the main stack to a level well below the allowable level
of the MACT, since those levels are currently being achieved, and thus
we are proposing to require such controls under CAA section 112(d)(6).
We evaluated whether there were additional controls to further reduce
emissions from the main stack and determined that lead emissions from
the main stack could be further reduced by replacing the standard cloth
bags with membrane bags at a capital cost of approximately $2 million
and an annual cost of $0.3 million. Assuming a 50 percent reduction
from 2008 main stack emissions, the cost of reducing lead emissions
would be about $40,000 to $229,000 per ton of lead. (See the Technical
Support Document included in the docket for a complete discussion of
this analysis.) Because the highest ambient air lead concentration
resulting from the emissions from the main stack already is more than
20 times below the level that is considered acceptable, it was
determined that although additional controls such as membrane bags
could result in additional emission reductions, the additional controls
are not warranted since they would not
[[Page 9434]]
appreciably reduce risk. We are proposing that the MACT standard, with
the changes we are proposing under the section 112(d)(6) technology
review as described in section V.D. below will provide an ample margin
of safety with regard to emissions of lead and other HAP from the main
stack.
D. What are the results and proposed decisions from the technology
review?
We evaluated developments in practices, processes, and control
technologies applicable to emission sources subject to the Primary Lead
Smelting MACT. This included a search of the RBLC Clearinghouse, the
California BACT Clearinghouse, the internet, and correspondence with
state agencies and industry. We have determined that there have been
advances in emission control measures since the Primary Lead Smelting
MACT standard was originally promulgated in 1999.
The 1999 MACT limit was set using the lead emission limits from the
lead SIPs for the three states in which primary lead smelting sources
were operational at the time of the rulemaking. EPA took each of the
three lead SIP limits, in lb/day, divided them by the corresponding
lead production capacity, in tons/day, and calculated a lead emission
rate in lb/ton. The results were as follows:
ASARCO--Missouri 1.0 lb/ton
ASARCO--Montana 1.0 lb/ton
Doe Run--Missouri 0.84 lb/ton
The values were ranked and the median value (1.0 lb/ton) was
selected as representative of the MACT floor.
Since the MACT standard was promulgated, the industry has undergone
significant changes. Two of the three facilities have shut down. The
only remaining primary lead smelting facility is the Doe Run smelter at
Herculaneum, Missouri, which is subject to control requirements under
the Missouri SIP for lead. The existing SIP, as well as a 2007 SIP
revision submitted by the State and proposed for approval by EPA
require numerous emissions-reducing measures and improvements to add-on
control devices, processes, and work practices. We considered these
developments in practices, processes, and control technologies in our
technology review.
Recent emissions tests (2000 through 2008) at the Doe Run facility
support that these improvements have resulted in significantly lower
emissions and demonstrate that actual lead emissions from the facility
are much lower than are allowed under the current MACT rule. To assess
the impacts of developments in practices, processes and control
technologies on lead emissions, emissions data from 2008 were compared
with emissions data from 2000. Data from 2008 were selected because
they reflect the many improvements that have been implemented at the
facility since promulgation of the MACT rule. Emissions data from
earlier years would not reflect all of the emission-reducing changes
that have been implemented at the Doe Run facility given that some of
the improvements were not implemented until 2007 and 2008. As described
above, technological improvements to baghouses and processes that have
been implemented at the facility since the MACT rule was promulgated
have resulted in substantially lower emissions from these sources at
this facility. These improvements include upgrade of cloth bags and
ventilation improvements. In 2008, lead emissions from the main stack,
which vents emissions from the sintering operation and the blast and
dross furnace, were 13.31 TPY. In addition, emissions from the furnace
area stack (i.e., the blast furnace and dross plant building which vent
to baghouse 7) were 1.81 TPY, for a total of approximately 15.1 TPY. At
the 2008 lead production rate of 149,500 tons, the lead emission rate
for these sources at Doe Run was about 0.2 lb/ton, or 80 percent less
than the current MACT limit of 1 lb/ton. Based on this demonstrated
performance, EPA believes that under Section 112(d)(6), the MACT
standard should be revised to reflect the reduction achieved in
practice.
Because we believe that the 2008 emissions of 13.31 TPY from the
main stack (or combined sintering/blast furnace/drossing operations)
reflect the annual rate of emissions achievable as a result of the
technological improvements that have been made since 1999, we are
proposing an emission limit based on the actual 2008 annual emissions
that vent to the main stack (i.e., sintering, blast furnace and
drossing operations). In order to account for variability in the
operation and emissions, recent stack tests were used to calculate the
95 percent upper predictive limit (UPL). The 95 percent UPL for the
main stack is 15 TPY. Variability in the operations and emission for
this source are discussed in more detail in Section E below.
Although we believe that there have been developments in processes,
practices and control technologies with regard to the furnace area
stack and with regard to refining and casting operations, as reflected
by the more stringent requirements that have been implemented in
accordance with the approved SIP and the 2007 SIP revisions; we are not
proposing additional requirements for these stacks as part of our
technology review because we have already proposed that these stacks
implement all feasible controls, regardless of cost, in order to ensure
that the risks due to these emission points are acceptable. Thus, there
are no additional developments in practices, processes and control
technologies beyond those which are reflected in the emission limits we
have proposed to meet CAA section 112(f)(2), above.
To be consistent with the existing MACT standard, EPA is proposing
to retain the plant-wide pound per ton of production format that
currently applies to the aggregate emissions from the main stack and
the furnace area stack. Because there are also stacks for the refining
and casting operations, we are proposing to include those emissions as
part of the plant-wide emission limit. Thus we are proposing a plant-
wide lead emission limit of 0.22 pounds of lead per ton of lead
produced based on the proposed reductions due to the section 112 (f)(2)
risk review for the furnace area and refining operations stacks
(discussed above in Section C) and the reduction in emissions from the
main stack (sinter/blast furnace/drossing operations) based on this
Section 112(d)(6) technology review This proposed plant-wide lead
emission limit was determined by summing the 15 TPY for the main stack
and the 0.91 TPY for the furnace area and the refining operation, and
dividing by the annual production from 2008 of 149,564 tons. We note
that variability was only applied in establishing technology-based
emissions from the main stack in order to establish a plant-wide
emission limit. Because the emission levels required from the refining
operation and furnace area stacks are based on acceptable risk, we
conclude it is not appropriate to consider variability in establishing
limits for these emission points.
We are proposing that the plant-wide lead emission limit apply to
new and existing facilities that are subject to the MACT. By default
this would include any new, controlled lead processing source not
currently covered, including lead processing by other than the current
techniques. We are requesting comment on the appropriateness of
applying the plant-wide lead emission limit to any future new lead
processing technique.
For the existing facility, compliance with the plant-wide stack
emission limit would be demonstrated in the same
[[Page 9435]]
manner as discussed above in section V.C.1 for the furnace area and
refining stack limit (i.e., stack testing on a quarterly basis). We are
proposing stack testing on a quarterly basis as opposed to testing on
an annual basis since this allows the facility the opportunity to
adjust their emissions throughout the year to be in compliance, rather
than to find they are out of compliance at the end of the year, thereby
risking violations. This schedule also coincides with other quarterly
monitoring and reporting required of the facility. Also as discussed in
section V.C.1, new primary lead processing facilities would be required
to demonstrate compliance using lead continuous emission monitoring
systems (CEMS).
E. Variability
In assessing sources' performance, EPA may consider variability
both in identifying which performers are ``best'' and in assessing
their level of performance. Brick MACT, 479 F. 3d at 881-82; see also
Mossville Envt'l Action Now v. EPA, 370 F.3d 1232, 1241-42 (D.C. Cir
2004) (EPA must exercise its judgment, based on an evaluation of the
relevant factors and available data, to determine the level of
emissions control that has been achieved by the best performing sources
considering these sources' operating variability).
Variability in lead producers' performance has a number of causes.
For emissions of lead compounds that are controlled by baghouses, the
variability is chiefly due to variations in performance of the control
device for which both run-to-run and test-to-test variability must be
accounted.\23\
---------------------------------------------------------------------------
\23\ Run-to-run variability is essentially within-test
variability, and encompasses variability in individual runs
comprising the compliance test, and includes uncertainties in
correlation of monitoring parameters and emissions, and imprecision
of stack test methods and laboratory analysis. 72 FR 54877 (Sept.
27, 2007). Test-to-test variability results from variability in
pollution device control efficiencies over time (depending on many
factors, including for fabric filters the point in the maintenance
cycle in which a fabric filter is tested). Test-to-test variability
can be termed long-term variability. 72 FR 54878.
---------------------------------------------------------------------------
In determining the contribution to a plant-wide emission limit of
the main stack, we considered annual emissions discharged from the air
pollution control devices that control lead emissions. For this rule,
we used the 2008 emissions reported by Doe Run to the State of
Missouri.
We assessed variability using a statistical formula designed to
estimate an emissions level that is equivalent to the source's
performance based on future compliance tests. Specifically, the
calculated limit is an upper prediction limit (UPL) calculated with the
Student's t-test using the TINV function in Microsoft Excel[supreg].
The Student's t-test has also been used in other EPA rulemakings (e.g.,
NESHAP for Portland Cement Manufacturing [75 FR 54970, September 9,
2010]; NSPS for Hospital/Medical/Infectious Waste Incinerators [74 FR
51368, October 6, 2009]; NESHAP for Industrial, Commercial, and
Institutional Boilers and Process Heaters-Proposed [75 FR 32006, June
4, 2010]) in accounting for variability. A prediction interval for a
future observation is an interval that will, with a specified degree of
confidence, contain the next (or some other pre-specified) randomly
selected observation from a population. In other words, the prediction
interval estimates what the upper bound of future values will be, based
upon present or past samples taken. The UPL consequently represents the
value which we can expect the mean of future observations (3-run
average for lead) to fall below within a specified level of confidence,
based upon the results of an independent sample from the same
population. In other words, if we were to randomly select a future test
condition from any of these sources (i.e., average of 3 runs or 30-day
average) we can be 95 percent confident that the reported level will
fall at or below the UPL value. Use of the UPL is appropriate in this
rulemaking because it sets a limit any single or future source can meet
based on the sources past performance.
This formula uses a pooled variance (in the s\2\ term) that
encompasses all the data-point to data-point variability. Where
variability was calculated using the UPL statistical approach, we used
the sample standard deviation calculated from the emissions data
distributions for lead. The standard deviation is the common measure of
the dispersion of the data set around an average. We note here that the
methodology accounts for both short-term and long-term variability and
encompasses run-to-run and test-to-test variability.
We adopted a form of the UPL equation that has been used in more
recent rulemakings. See 75 FR 54970 (September 9, 2010), 75 FR 32020
(June 4, 2010) and 75 FR 31905 (June 4, 2010). The UPL used in this
proposed rule is calculated by:
[GRAPHIC] [TIFF OMITTED] TP17FE11.000
Where:
x = 2008 annual emissions
n = the number of test runs
m = the number of test runs in the compliance average
s\2\ = observed variance
t = student t distribution statistic
This calculation was performed using the following Excel functions: 95
percent UPL = 2008 annual emissions + [STDEV (Test Runs) x TINV (2 x
probability, n-1 degrees of freedom) x SQRT ((1/n) + (1/m))], for a
one-tailed t-value, probability of 0.05, and sample size of n.
F. What other actions are we proposing?
As discussed in Section III.C. above, EPA is proposing to remove
provisions in the existing standard that would have exempted sources
from complying with the standard during periods of startup, shutdown
and malfunction. Specifically we are proposing revisions to subpart TTT
Table 1 and rule provisions to remove applicability of the General
Provisions with regard to SSM and remove the exemption for bag leak
detection alarm time attributable to SSM events from determining
compliance with the total alarm time limit. In addition, we are
proposing to promulgate an affirmative defense to civil penalties for
exceedances of emission limits caused by malfunctions, as well as
criteria for establishing the affirmative defense.
EPA has attempted to ensure that we have not included in the
proposed regulatory language any provisions that are inappropriate,
unnecessary, or redundant in the absence of the SSM exemption. We are
specifically seeking comment on whether there are any such provisions
that we have inadvertently incorporated or overlooked.
[[Page 9436]]
VI. Proposed Action
A. What actions are we proposing as a result of the residual risk
reviews?
Consistent with CAA section 112 (f)(2), we are proposing to amend
the MACT standard for primary lead processing to include a lead
concentration in air limit of 0.15 [micro]g/m3 (based on 3-month
rolling averages)to be measured at locations approved by the
Administrator to address the risks from all fugitive dust emissions
addressed in 40 CFR 63.1544. We are also proposing to remove refining
and casting operations from Sec. 63.1544 and to require that emissions
from these operations be vented to one or more stacks. Finally, we are
proposing to establish an emission cap of 0.91 TPY for the furnace area
stack and the refining operation stacks. These limits were established
based on the level of reductions in lead emissions from the three
sources that are necessary to show that the lead NAAQS will not be
exceeded within the 50 km modeled domain. We believe the NAAQS level
represents an acceptable level of risk and that the proposed limits are
necessary to ensure that risks from these sources are acceptable. We
are proposing that the risk posed by lead emissions from the main stack
and by emissions of all other HAP is acceptable.
We are proposing that compliance with the emission limits
applicable to the furnace area and refinery stacks would be
demonstrated based on stack testing for existing facilities and, for
new facilities, using CEMS after promulgation of performance
specifications for a CEMS capable of measuring lead emissions.
We are proposing that compliance with the lead concentration in air
limit would be demonstrated using a compliance monitoring system
approved by the Administrator.
We are also proposing that the Primary Lead Smelting standard, as
we have proposed to revise it to ensure an acceptable level of risk,
will also protect public health with an ample margin of safety. With
regard to lead emissions from fugitive dust sources and from the
furnace and refining area stacks, we have not identified any feasible
controls beyond those needed to meet the proposed emission limits that
will provide an acceptable level of risk . The standards we are
proposing to ensure an acceptable level of risk for lead emissions will
also reduce the risk from cadmium and will also reduce emissions of all
other metal HAP known to be emitted from this source category because
the controls that will reduce lead emissions are the same controls that
will reduce emissions of these other metal HAP. The cancer risk from
cadmium emissions will be reduced from 30-in-1 million to less than 1-
in-1 million. Therefore, we are proposing that the existing MACT, as it
would be modified based on our proposed requirements for lead
emissions, would provide an ample margin of safety with respect to
emissions from all metal HAP.
With regard to lead emissions from the main stack, we have
identified developments in practices, processes and control
technologies since promulgation of the MACT standard in 1999, and are
proposing a reduced emission limit for the main stack based on these
improvements. Since the main stack does not pose an unacceptable risk
at its current emissions level, we are not proposing reductions for
this emission point under 112(f)(2). However, we are proposing a
reduced emission limit under 112(d)(6) due to the improvements we
identified.
B. What actions are we proposing as a result of the technology reviews?
For the Primary Lead Smelting source category, we have determined
that there have been developments in practices, processes, or control
technologies since the promulgation of the MACT standards that are
feasible for the one facility in this source category to implement at
the main stack. The proposed limit is consistent with the current
demonstrated performance of the facility based on obligations adopted
by the State and reflected in the 2002 SIP and 2007 SIP revision for
Doe Run.
We are proposing that a performance of 15.11 TPY has been
demonstrated for emissions from the main stack, taking into
consideration variability of emissions from that stack. The existing
MACT lead emissions standard that is applicable to emissions from the
main stack is a plant-wide emission limit that also applies to
emissions from the furnace-area stack. We are proposing to revise the
plant-wide limit to reflect the 15.11 TPY limit for the main stack as
well as the emissions limits we are proposing for the furnace-area and
refinery stacks under CAA section 112(f)(2). Thus, we are proposing to
revise the plant-wide emissions limit from 1 pound of lead per ton of
lead produced, to 0.22 pound of lead per ton of lead produced and the
new limit would include emissions from the refinery stack as well as
emissions from the main stack and the furnace area stack. Compliance
with this limit would be demonstrated quarterly with stack testing. For
new facilities, compliance would be demonstrated using lead CEMS.
C. What other actions are we proposing?
As described above, we are proposing to amend the applicability
section for the MACT rule to tailor it to the definition of the source
category we established under CAA section 112(c)(1). See
``Documentation for Development of Initial Source Category List--Final
Report'', USEPA/OAQPS, EPA-450/3-91-030, July, 1992. In support of this
applicability provision clarification, we are also proposing to replace
the definition of ``primary lead smelter'' with a definition of
``primary lead processor''. The ``primary lead processor'' definition
would include any facility that produces lead from processing of lead
sulfide ore by pyrometallurgical (smelting) or any other technique. We
are also proposing to add definitions of ``secondary lead smelters'',
``lead refiners'', and ``lead remelters'' to clarify the meaning of
those terms in the second sentence of the applicability provision.
We propose to amend the Primary Lead Smelting MACT standards to
remove the language that exempts bag leak detection system alarm time
incurred during periods of SSM from inclusion in the allowable alarm
time. This change is being made to ensure the rule is consistent with
the court's ruling in Sierra Club v. EPA, 551 F.3d 1019 (D.C. Cir.
2008). We are also proposing minor modifications throughout the rule to
incorporate plain language and to make editorial and clarifying
revisions. In addition, we are proposing changes to Table 1 of the rule
to reflect revisions to SSM requirements.
D. Compliance Dates
We are proposing that the requirements under CAA section 112(f)(2)
for the one existing source, if finalized, must be implemented no later
than two years after the effective date of this rule. Consistent with
CAA section 112(f)(4)(B), we are proposing that a two-year compliance
period is necessary so the facility has adequate time to install
additional controls and demonstrate compliance, including the time
necessary to purchase, install and test replacement bags, or if the
facility decides to add a new baghouse in series with an existing
baghouse, seek bids, select a vendor, install and test the new
equipment; prepare and submit the required monitoring plan to monitor
lead concentrations in air; purchase, install and conduct quality
assurance and quality control measures on compliance monitoring
equipment and; conduct site remediation necessary to
[[Page 9437]]
reduce fugitive emissions. A two-year compliance period is also
consistent with the schedule of required actions contained in the
Consent Decree.
In addition, we are proposing that the plant-wide limit that would
reflect reductions required for the main stack pursuant to CAA section
112(d)(6) and for the furnace area and refinery stacks pursuant to CAA
section 112(f)(2) must be met no later than two years after the
effective date of this rule. Because these limits reflect the
reductions from the furnace area and refinery stacks required under
section 112(f)(2), we believe a two-year compliance timeframe is needed
for the same reasons provided above.
VII. Request for Comments
We are soliciting comments on all aspects of this proposed action.
All comments received during the comment period will be considered. In
addition to general comments on this proposed actions, we are also
interested in any additional data that may help to reduce the
uncertainties inherent in the risk assessments. We are specifically
interested in receiving corrections to the dataset used for risk
modeling. Such data should include supporting documentation in
sufficient detail to allow characterization of the quality and
representativeness of the data or information. Please see the following
section for more information on submitting data.
VIII. Submitting Data Corrections
The facility-specific data used in the source category risk
analyses and demographic analyses are available for download on the RTR
Web Page at http://www.epa.gov/ttn/atw/rrisk/rtrpg.html. The data files
include detailed information for each HAP emissions release point for
the facility included in the source category.
If you believe the data are not representative or are inaccurate,
please identify the data in question, provide your reason for concern,
and provide any ``improved'' data that you have, if available. When you
submit data, we request that you provide documentation of the basis for
the revised values to support your suggested changes. To submit
comments on the data downloaded from the RTR Web page, complete the
following steps:
(1) Within this downloaded file, enter suggested revisions to the
data fields appropriate for that information. The data fields that may
be revised include the following:
------------------------------------------------------------------------
Data element Definition
------------------------------------------------------------------------
Control Measure................. Are control measures in place? (yes or
no).
Control Measure Comment......... Select control measure from list
provided, and briefly describe the
control measure.
Delete.......................... Indicate here if the facility or
record should be deleted.
Delete Comment.................. Describes the reason for deletion.
Emission Calculation Method Code Code description of the method used to
For Revised Emissions. derive emissions. For example, CEM,
material balance, stack test, etc.
Emission Process Group.......... Enter the general type of emission
process associated with the specified
emission point.
Fugitive Angle.................. Enter release angle (clockwise from
true North); orientation of the y-
dimension relative to true North,
measured positive for clockwise
starting at 0 degrees (maximum 89
degrees).
Fugitive Length................. Enter dimension of the source in the
east-west (x-) direction, commonly
referred to as length (ft).
Fugitive Width.................. Enter dimension of the source in the
north-south (y-) direction, commonly
referred to as width (ft).
Malfunction Emissions........... Enter total annual emissions due to
malfunctions (TPY).
Malfunction Emissions Max Hourly Enter maximum hourly malfunction
emissions here (lb/hr).
North American Datum............ Enter datum for latitude/longitude
coordinates (NAD27 or NAD83); if left
blank, NAD83 is assumed.
Process Comment................. Enter general comments about process
sources of emissions.
REVISED Address................. Enter revised physical street address
for MACT facility here.
REVISED City.................... Enter revised city name here.
REVISED County Name............. Enter revised county name here.
REVISED Emission Release Point Enter revised Emission Release Point
Type. Type here.
REVISED End Date................ Enter revised End Date here.
REVISED Exit Gas Flow Rate...... Enter revised Exit Gas Flowrate here
(ft\3\/sec).
REVISED Exit Gas Temperature.... Enter revised Exit Gas Temperature
here (F).
REVISED Exit Gas Velocity....... Enter revised Exit Gas Velocity here
(ft/sec).
REVISED Facility Category Code.. Enter revised Facility Category Code
here, which indicates whether
facility is a major or area source.
REVISED Facility Name........... Enter revised Facility Name here.
REVISED Facility Registry Enter revised Facility Registry
Identifier. Identifier here, which is an ID
assigned by the EPA Facility Registry
System.
REVISED HAP Emissions Enter revised HAP Emissions
Performance Level Code. Performance Level here.
REVISED Latitude................ Enter revised Latitude here (decimal
degrees).
REVISED Longitude............... Enter revised Longitude here (decimal
degrees).
REVISED MACT Code............... Enter revised MACT Code here.
REVISED Pollutant Code.......... Enter revised Pollutant Code here.
REVISED Routine Emissions....... Enter revised routine emissions value
here (TPY).
REVISED SCC Code................ Enter revised SCC Code here.
REVISED Stack Diameter.......... Enter revised Stack Diameter here
(ft).
REVISED Stack Height............ Enter revised Stack Height here (Ft).
REVISED Start Date.............. Enter revised Start Date here.
REVISED State................... Enter revised State here.
REVISED Tribal Code............. Enter revised Tribal Code here.
REVISED Zip Code................ Enter revised Zip Code here.
Shutdown Emissions.............. Enter total annual emissions due to
shutdown events (TPY).
Shutdown Emissions Max Hourly... Enter maximum hourly shutdown
emissions here (lb/hr).
[[Page 9438]]
Stack Comment................... Enter general comments about emission
release points.
Startup Emissions............... Enter total annual emissions due to
startup events (TPY).
Startup Emissions Max Hourly.... Enter maximum hourly startup emissions
here (lb/hr).
Year Closed..................... Enter date facility stopped
operations.
------------------------------------------------------------------------
2. Fill in the commenter information fields for each suggested
revision (i.e., commenter name, commenter organization, commenter e-
mail address, commenter phone number, and revision comments).
3. Gather documentation for any suggested emissions revisions
(e.g., performance test reports, material balance calculations, etc.).
4. Send the entire downloaded file with suggested revisions in
Microsoft[supreg] Access format and all accompanying documentation to
Docket ID Number EPA-HQ-OAR-2004-0305 (through one of the methods
described in the ADDRESSES section of this preamble). To expedite
review of the revisions, it would also be helpful if you submitted a
copy of your revisions to the EPA directly at [email protected] in addition
to submitting them to the docket.
5. If you are providing comments on a facility, you need only
submit one file for that facility, which should contain all suggested
changes for all sources at that facility. We request that all data
revision comments be submitted in the form of updated Microsoft[supreg]
Access files, which are provided on the http://www.epa.gov/ttn/atw/rrisk/rtrpg.html Web page.
IX. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review
Under Executive Order 12866 (58 FR 51735, October 4, 1993), this
action is a significant regulatory action because it raises novel legal
and policy issues. Accordingly, EPA submitted this action to the Office
of Management and Budget (OMB) for review under Executive Order 12866
and any changes made in response to OMB recommendations have been
documented in the docket for this action.
B. Paperwork Reduction Act
The information collection requirements 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. The
Information Collection Request (ICR) document prepared by EPA has been
assigned EPA ICR number 1856.07.
We are proposing new paperwork requirements to the Primary Lead
Smelting source category in the form of monitoring for lead
concentrations in air and increased frequency for stack testing as
described in 40 CFR 63.1547(k) (compliance monitoring) and 40 CFR
63.1546 (stack testing). These requirements are described in section
VI.A and B. Although these are additional requirements under today's
proposed rule, they are consistent with existing monitoring and testing
currently conducted by the facility to meet MACT and SIP requirements.
Therefore, we do not believe that the additional paperwork required by
these proposed changes would constitute an undue burden to the
facility.
We estimate one regulated entity is currently subject to subpart
TTT and will be subject to all proposed standards. This facility will
have no capital costs associated with the information collection
requirements in the proposed rule.
The estimated recordkeeping and reporting burden after the
effective date of the proposed rule is estimated to be 1,323 labor
hours at a cost of $465,503. This estimate includes the cost of
reporting, including reading instructions, and information gathering.
Recordkeeping cost estimates include reading instructions, planning
activities, monitoring plan development, conducting compliance
monitoring, sampling and analysis and maintenance of rolling 3-month
average data. The average hours and cost per regulated entity would be
1,323 hours and $465,503 based on one facility response per year.
Burden is defined at 5 CFR 1320.3(b).
An agency may not conduct or sponsor, and a person is not required
to respond to, a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for EPA's
regulations in 40 CFR are listed in 40 CFR part 9.
To comment on the Agency's need for this information, the accuracy
of the provided burden estimates, and any suggested methods for
minimizing respondent burden, EPA has established a public docket for
this rule, which includes this ICR, under Docket ID number EPA-HQ-OAR-
2004-0305. Submit any comments related to the ICR to EPA and OMB. See
ADDRESSES section at the beginning of this notice for where to submit
comments to EPA. Send comments to OMB at the Office of Information and
Regulatory Affairs, Office of Management and Budget, 725 17th Street,
NW., Washington, DC 20503, Attention: Desk Office for EPA. Since OMB is
required to make a decision concerning the ICR between 30 and 60 days
after February 17, 2011, a comment to OMB is best assured of having its
full effect if OMB receives it by March 21, 2011. The final rule will
respond to any OMB or public comments on the information collection
requirements contained in this proposal.
C. Regulatory Flexibility Act
The Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedure Act or any other statute unless the agency certifies that the
rule will not have a significant economic impact on a substantial
number of small entities. Small entities include small businesses,
small organizations, and small governmental jurisdictions. For purposes
of assessing the impacts of today's proposed rule on small entities,
small entity is defined as: (1) A small business that is a small
industrial entity as defined by the Small Business Administration's
(SBA) regulations at 13 CFR 121.201; (2) a small governmental
jurisdiction that is a government of a city, county, town, school
district or special district with a population of less than 50,000; and
(3) a small organization that is any not-for-profit enterprise which is
independently owned and operated and is not dominant in its field.
After considering the economic impacts of today's proposed rule on
small entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities. This
proposed rule will not impose any requirements on small entities. This
proposed rule is currently applicable to one operating facility that
does not meet the definition of a small entity.
We continue to be interested in the potential impacts of the
proposed rule on small entities and welcome comments on issues related
to such impacts.
[[Page 9439]]
D. Unfunded Mandates Reform Act
This proposed rule does not contain a federal mandate under the
provisions of Title II of the Unfunded Mandates Reform Act of 1995
(UMRA), 2 U.S.C. 1531-1538 for State, local, or tribal governments or
the private sector. The proposed rule would not result in expenditures
of $100 million or more for State, local, and tribal governments, in
aggregate, or the private sector in any 1 year. The proposed rule
imposes no enforceable duties on any State, local or tribal governments
or the private sector. Thus, this proposed rule is not subject to the
requirements of sections 202 or 205 of the UMRA.
This proposed rule is also not subject to the requirements of
section 203 of UMRA because it contains no regulatory requirements that
might significantly or uniquely affect small governments because it
contains no requirements that apply to such governments nor does it
impose obligations upon them.
E. Executive Order 13132: Federalism
This proposed rule does not have federalism implications. It will
not have substantial direct effects on the States, on the relationship
between the national government and the States, or on the distribution
of power and responsibilities among the various levels of government,
as specified in Executive Order 13132. None of the facilities subject
to this action are owned or operated by State governments, and, because
no new requirements are being promulgated, nothing in this proposal
will supersede State regulations. Thus, Executive Order 13132 does not
apply to this proposed rule.
In the spirit of Executive Order 13132, and consistent with EPA
policy to promote communications between EPA and State and local
governments, EPA specifically solicits comment on this proposed rule
from State and local officials.
F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments
Subject to the Executive Order 13175 (65 FR 67249, November 9,
2000) EPA may not issue a regulation that has tribal implications, that
imposes substantial direct compliance costs, and that is not required
by statute, unless the Federal government provides the funds necessary
to pay the direct compliance costs incurred by tribal governments, or
EPA consults with tribal officials early in the process of developing
the proposed regulation and develops a tribal summary impact statement.
EPA has concluded that this proposed rule will not have tribal
implications, as specified in Executive Order 13175. It will not have
substantial direct effect on tribal governments, on the relationship
between the federal government and Indian tribes, or on the
distribution of power and responsibilities between the Federal
government and Indian tribes, as specified in Executive Order 13175.
Thus, Executive Order 13175 does not apply to this action.
EPA specifically solicits additional comment on this proposed
action from tribal officials.
G. Executive Order 13045: Protection of Children From Environmental
Health Risks and Safety Risks
This proposed rule is not subject to Executive Order 13045 (62 FR
19885, April 23, 1997) because it is not economically significant as
defined in Executive Order 12866. However, the Agency does believe
there is a disproportionate risk to children. Modeled ambient air lead
concentrations from the one facility in this source category are in
excess of the NAAQS for lead, which was set to ``provide increased
protection for children and other at-risk populations against an array
of adverse health effects, most notably including neurological effects
in children, including neurocognitive and neurobehavioral effects.'' 73
FR 67007. However, the control measures proposed in this notice will
result in lead concentration levels that are in compliance with the
lead NAAQS, thereby mitigating the risk of adverse health effects to
children.
H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use
This action is not a ``significant energy action'' as defined under
Executive Order 13211, ``Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use'' (66 FR
28355, May 22, 2001), because it is not likely to have significant
adverse effect on the supply, distribution, or use of energy. This
action will not create any new requirements for sources in the energy
supply, distribution, or use sectors.
I. National Technology Transfer and Advancement Act
Section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (``NTTAA''), Public Law 104-113, 12(d) (15 U.S.C. 272 note)
directs EPA to use voluntary consensus standards in its regulatory
activities unless to do so would be inconsistent with applicable law or
otherwise impractical. Voluntary consensus standards are technical
standards (e.g., materials specifications, test methods, sampling
procedures, and business practices) that are developed or adopted by
voluntary consensus standards bodies. The NTTAA directs EPA to provide
Congress, through OMB, explanations when the Agency decides not to use
available and applicable voluntary consensus standards.
This proposed rulemaking does not involve technical standards.
Therefore, EPA is not considering the use of any voluntary consensus
standards.
J. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations
Executive Order 12898 (59 FR 7629, February 16, 1994) establishes
federal executive policy on environmental justice. Its main provision
directs federal agencies, to the greatest extent practicable and
permitted by law, to make environmental justice part of their mission
by identifying and addressing, as appropriate, disproportionately high
and adverse human health or environmental effects of their programs,
policies, and activities on minority populations and low-income
populations in the United States.
To examine the potential for any environmental justice issues that
might be associated with each source category, we evaluated the
distributions of HAP-related cancer and non-cancer risks across
different social, demographic, and economic groups within the
populations living near the facilities where these source categories
are located. The methods used to conduct demographic analyses for this
rule are described in section IV.A of the preamble for this rule. The
development of demographic analyses to inform the consideration of
environmental justice issues in EPA rulemakings is an evolving science.
The EPA offers the demographic analyses in today's rulemaking as
examples of how such analyses might be developed to inform such
consideration, and invites public comment on the approaches used and
the interpretations made from the results, with the hope that this will
support the refinement and improve utility of such analyses for future
rulemakings.
In the case of Primary Lead Processing, we focused on populations
within 50 km of the one facility in this source category with emission
sources subject to the MACT standard. More specifically, for these
populations we
[[Page 9440]]
evaluated exposures to HAP which could result in cancer risks of 1-in-1
million or greater, or population exposures to ambient air lead
concentrations above the level of the NAAQS for lead. We compared the
percentages of particular demographic groups within the focused
populations to the total percentages of those demographic groups
nationwide. The results of this analysis are documented in section
V.B.1 (see Table 6), as well as in a technical report located in the
docket for this rulemaking. In brief, although our analyses show that
there is the potential for adverse environmental and human health
effects from emissions of lead, it does not indicate any significant
potential for disparate impacts to the specific demographic groups
analyzed (see section V.B.1). Notably however, the proposed rule would
require additional control measures to address the identified
environmental and health risks and would therefore, decrease risks to
any populations exposed to these sources.
List of Subjects in 40 CFR Part 63
Environmental protection, Air pollution control, Reporting and
recordkeeping requirements, Lead.
Dated: January 31, 2011.
Lisa P. Jackson,
Administrator.
For reasons set out in the preamble, title 40, chapter I, of the
Code of Federal Regulations is proposed to be amended:
PART 63--[AMENDED]
1. The authority citation for part 63 continues to read as follows:
Authority: 42 U.S.C. 7401 et seq.
2. Section 63.1541 is revised to read as follows:
Sec. 63.1541 Applicability.
(a) The provisions of this subpart apply to any facility engaged in
producing lead metal from ore concentrates. The category includes, but
is not limited to, the following smelting processes: Sintering,
reduction, preliminary treatment, refining and casting operations,
process fugitive sources, and fugitive dust sources. The sinter process
includes an updraft or downdraft sintering machine. The reduction
process includes the blast furnace, electric smelting furnace with a
converter or reverberatory furnace, and slag fuming furnace process
units. The preliminary treatment process includes the drossing kettles
and dross reverberatory furnace process units. The refining process
includes the refinery process unit. The provisions of this subpart do
not apply to secondary lead smelters, lead refiners, or lead remelters.
(b) Table 1 of this subpart specifies the provisions of subpart A
of this part that apply and those that do not apply to owners and
operators of primary lead processors.
3. Section 63.1542 is amended by:
a. Adding in alphabetical order definitions for ``Affirmative
defense,'' ``Lead refiner,'' ``Lead remelter,'' ``Primary lead
processor,'' and ``Secondary lead smelter''.
b. Removing the definition for ``Primary lead smelter''.
c. Revising the definitions for ``Fugitive dust source,'' ``Furnace
area,'' ``Malfunction,'' ``Materials storage and handling area,''
``Plant roadway,'' ``Process fugitive source,'' ``Refining and casting
area,'' Sinter machine area,'' and ``Tapping location''.
Sec. 63.1542 Definitions.
* * * * *
Affirmative defense means, in the context of an enforcement
proceeding, a response or defense put forward by a defendant, regarding
which the defendant has the burden of proof, and the merits of which
are independently and objectively evaluated in a judicial or
administrative proceeding.
* * * * *
Fugitive dust source means a stationary source of hazardous air
pollutant emissions at a primary lead processor resulting from the
handling, storage, transfer, or other management of lead-bearing
materials where the source is not part of a specific process, process
vent, or stack. Fugitive dust sources include roadways, storage piles,
materials handling transfer points, and materials transport areas.
Furnace area means any area of a primary lead processor in which a
blast furnace or dross furnace is located.
Lead refiner means any facility that refines lead metal that is not
located at a primary lead processor.
Lead remelter means any facility that remelts lead metal that is
not located at a primary lead processor.
Malfunction means any sudden, infrequent, and not reasonably
preventable failure of air pollution control and monitoring equipment,
process equipment, or a process to operate in a normal or usual manner
which causes, or has the potential to cause, the emission limitations
in an applicable standard to be exceeded. Failures that are caused in
part by poor maintenance or careless operation are not malfunctions.
Materials storage and handling area means any area of a primary
lead processor in which lead-bearing materials (including ore
concentrate, sinter, granulated lead, dross, slag, and flue dust) are
stored or handled between process steps, including areas in which
materials are stored in piles, bins, or tubs, and areas in which
material is prepared for charging to a sinter machine or smelting
furnace or other lead processing operation.
* * * * *
Plant roadway means any area of a primary lead processor that is
subject to vehicle traffic, including traffic by forklifts, front-end
loaders, or vehicles carrying ore concentrates or cast lead ingots.
Excluded from this definition are employee and visitor parking areas,
provided they are not subject to traffic by vehicles carrying lead-
bearing materials.
Primary lead processor means any facility engaged in the production
of lead metal from lead sulfide ore concentrates through the use of
pyrometallurgical or other techniques.
Process fugitive source means a source of hazardous air pollutant
emissions at a primary lead processor that is associated with lead
smelting, processing or refining but is not the primary exhaust stream
and is not a fugitive dust source. Process fugitive sources include
sinter machine charging locations, sinter machine discharge locations,
sinter crushing and sizing equipment, furnace charging locations,
furnace taps, and drossing kettle and refining kettle charging or
tapping locations.
Refining and casting area means any area of a primary lead
processor in which drossing or refining operations occur, or casting
operations occur.
Secondary lead smelter means any facility at which lead-bearing
scrap material, primarily, but not limited to, lead-acid batteries, is
recycled into elemental lead or lead alloys by smelting.
* * * * *
Sinter machine area means any area of a primary lead processor
where a sinter machine, or sinter crushing and sizing equipment is
located.
* * * * *
Tapping location means the opening through which lead and slag are
removed from the furnace.
4. Section 63.1543 is revised to read as follows:
Sec. 63.1543 Standards for process and process fugitive sources.
(a) No owner or operator of any existing, new, or reconstructed
primary lead processor shall discharge or cause to be discharged into
the atmosphere lead compounds in excess of 0.22
[[Page 9441]]
pounds per ton of lead metal produced from the aggregation of emissions
discharged from air pollution control devices used to control emissions
at primary lead processing facilities, including the sources listed in
paragraphs (a)(1) through (a)(10) of this section.
(1) Sinter machine;
(2) Blast furnace;
(3) Dross furnace;
(4) Dross furnace charging location;
(5) Blast furnace and dross furnace tapping location;
(6) Sinter machine charging location;
(7) Sinter machine discharge end;
(8) Sinter crushing and sizing equipment;
(9) Sinter machine area; and
(10) Refining and casting, and furnace area.
(b) No owner or operator of any existing, new, or reconstructed
primary lead processor shall discharge or cause to be discharged into
the atmosphere lead compounds in excess of 0.91 tons per year from the
air pollution control devices used to control emissions from furnace
area and refining and casting operations.
(c) The process fugitive sources listed in paragraphs (a)(4)
through (a)(8) of this section must be equipped with a hood and must be
ventilated to a baghouse or equivalent control device. The hood design
and ventilation rate must be consistent with American Conference of
Governmental Industrial Hygienists recommended practices.
(d) The sinter machine area must be enclosed in a building that is
ventilated to a baghouse or equivalent control device at a rate that
maintains a positive in-draft through any doorway opening.
(e) Except as provided in paragraph (f) of this section, following
the initial tests to demonstrate compliance with paragraphs (a)and (b)
of this section, the owner or operator of a primary lead processor must
conduct compliance tests for lead compounds on an quarterly basis (no
later than 100 days following any previous compliance test).
(f) If the 12 most recent compliance tests demonstrate compliance
with the emission limit specified in paragraphs (a) and (b) of this
section, the owner or operator of a primary lead processor shall be
allowed up to 12 calendar months from the last compliance test to
conduct the next compliance test for lead compounds.
(g) The owner or operator of a primary lead processor must maintain
and operate each baghouse used to control emissions from the sources
listed in paragraphs (a)(1) through (a)(10) of this section such that
the alarm on a bag leak detection system required under Sec.
63.1547(c)(8) does not sound for more than five percent of the total
operating time in a 6-month reporting period.
(h) The owner or operator of a primary lead processor must record
the date and time of a bag leak detection system alarm and initiate
procedures to determine the cause of the alarm according to the
corrective action plan required under Sec. 63.1547(f) within 1 hour of
the alarm. The cause of the alarm must be corrected as soon as
practicable.
(i) At all times, the owner or operator must operate and maintain
any affected source, including associated air pollution control
equipment and monitoring equipment, in a manner consistent with safety
and good air pollution control practices for minimizing emissions.
Determination of whether such operation and maintenance procedures are
being used will be based on information available to the Administrator
which may include, but is not limited to, monitoring results, review of
operation and maintenance procedures, review of operation and
maintenance records, and inspection of the source.
5. Section 63.1544 is revised to read as follows:
Sec. 63.1544 Standards for fugitive dust sources.
(a) No owner or operator of any existing, new or reconstructed
primary lead processor shall discharge or cause to be discharged into
the atmosphere lead compounds that cause the concentration of lead in
air to exceed 0.15 [micro]g/m\3\ on a 3-month rolling average measured
at locations approved by the Administrator.
(b) At all times, the owner or operator must operate and maintain
any affected source, including associated air pollution control
equipment and monitoring equipment, in a manner consistent with safety
and good air pollution control practices for minimizing emissions.
Determination of whether such operation and maintenance procedures are
being used will be based on information available to the Administrator
which may include, but is not limited to, monitoring results, review of
operation and maintenance procedures, review of operation and
maintenance records, and inspection of the source.
6. Section 63.1545 is revised to read as follows:
Sec. 63.1545 Compliance dates.
(a) Each owner or operator of an existing primary lead processor
must achieve compliance with the requirements of this subpart no later
than [DATE TWO YEARS FROM PUBLICATION OF THE FINAL RULE IN THE FEDERAL
REGISTER].
(b) Each owner or operator of a new primary lead processor must
achieve compliance with the requirements of this subpart no later than
[DATE 60 DAYS AFTER PUBLICATION OF THE FINAL RULE IN THE FEDERAL
REGISTER] or startup, whichever is later.
7. Section 63.1546 is revised to read as follows:
Sec. 63.1546 Performance testing.
(a) The following procedures must be used to determine quarterly
compliance with the emissions standard for lead compounds under Sec.
63.1543(a) and (b) for existing sources:
(1) Each owner or operator of existing sources listed in Sec.
63.1543(a)(1) through (10) must determine the lead compound emissions
rate, in units of pounds of lead per hour according to the following
test methods in appendices of part 60 of this chapter:
(i) Method 1 to appendix A-1 of 40 CFR part 60 must be used to
select the sampling port location and the number of traverse points.
(ii) Methods 2 and 2F of appendix A-1 and Method 2G of appendix A-2
of 40 CFR part 60 must be used to measure volumetric flow rate.
(iii) Methods 3, 3A, 3B of appendix A-2 of 40 CFR part 60 must be
used for gas analysis.
(iv) Method 4 of appendix A-3 of 40 CFR part 60 must be used to
determine moisture content of the stack gas.
(v) Method 12 of appendix A-5 or Method 29 of appendix A-8 of 40
CFR part 60 must be used to determine lead emissions rate of the stack
gas.
(2) A performance test shall consist of at least three runs. For
each test run with Method 12 of appendix A-5 or Method 29 of appendix
A-8 of 40 CFR part 60, the minimum sample time must be 60 minutes and
the minimum volume must be 1 dry standard cubic meter (35 dry standard
cubic feet).
(3) Performance tests shall be completed quarterly, once every 3
months, to determine compliance.
(4) The lead emission rate in pounds per quarter is calculated by
multiplying the quarterly lead emission rate in pounds per hour by the
quarterly plant operating time, in hours as shown in Equation 1:
[GRAPHIC] [TIFF OMITTED] TP17FE11.001
Where:
EPb = quarterly lead emissions, pounds per quarter;
[[Page 9442]]
ERPb = quarterly lead emissions rate, pounds per hour;
and
QPOT = quarterly plant operating time, hours per quarter.
(5) The lead production rate, in units of tons per quarter, must be
determined based on production data for the previous quarter according
to the procedures detailed in paragraphs (a)(5)(i) through (iv) of this
section:
(i) Total lead products production multiplied by the fractional
lead content must be determined in units of tons.
(ii) Total copper matte production multiplied by the fractional
lead content must be determined in units of tons.
(iii) Total copper speiss production multiplied by the fractional
lead content must be determined in units of tons.
(iv) Total quarterly lead production must be determined by summing
the values obtained in paragraphs (a)(5)(i) through (a)(5)(iii) of this
section.
(6) To determine compliance with the production-based lead compound
emission rate in Sec. 63.1543(a), the quarterly production-based lead
compound emission rate, in units of pounds of lead emissions per ton of
lead produced, is calculated as shown in Equation 2 by dividing lead
emissions by lead production.
[GRAPHIC] [TIFF OMITTED] TP17FE11.002
Where:
CEPb = quarterly production-based lead compound emission
rate, in units of pounds of lead emissions per ton of lead produced;
EPb = quarterly lead emissions, pounds per quarter; and
PPb = quarterly lead production, tons per quarter.
(7) To determine quarterly compliance with the emissions standard
for lead compounds under Sec. 63.1543(b), sum the lead compound
emission rates for the current and previous three quarters for the
sources in Sec. 63.1543 (a)(10) to determine compliance with Sec.
63.1543(b), as determined in accordance with paragraphs (a)(1) through
(a)(4) of this section.
(b) Owner and operators must perform an initial compliance test to
demonstrate compliance with the sinter building in-draft requirements
of Sec. 63.1543(d) at each doorway opening in accordance with
paragraphs (b)(1) through (b)(4) of this section.
(1) Use a propeller anemometer or equivalent device.
(2) Determine doorway in-draft by placing the anemometer in the
plane of the doorway opening near its center.
(3) Determine doorway in-draft for each doorway that is open during
normal operation with all remaining doorways in their customary
position during normal operation.
(4) Do not determine doorway in-draft when ambient wind speed
exceeds 2 meters per second.
(c) Performance tests shall be conducted under such conditions as
the Administrator specifies to the owner or operator based on
representative performance of the affected source for the period being
tested. Upon request, the owner or operator shall make available to the
Administrator such records as may be necessary to determine the
conditions of performance tests.
8. Section 63.1547 is revised to read as follows:
Sec. 63.1547 Monitoring requirements.
(a) Owners and operators of primary lead processors must prepare,
and at all times operate according to, a standard operating procedures
manual that describes in detail the procedures for inspection,
maintenance, and bag leak detection and corrective action for all
baghouses that are used to control process, process fugitive, or
fugitive dust emissions from any source subject to the lead emission
standards in Sec. Sec. 63.1543 and 63.1544, including those used to
control emissions from general ventilation systems.
(b) The standard operating procedures manual for baghouses required
by paragraph (a) of this section must be submitted to the Administrator
or delegated authority for review and approval.
(c) The procedures specified in the standard operating procedures
manual for inspections and routine maintenance must, at a minimum,
include the requirements of paragraphs (c)(1) through (c)(8) of this
section.
(1) Weekly confirmation that dust is being removed from hoppers
through visual inspection or equivalent means of ensuring the proper
functioning of removal mechanisms.
(2) Daily check of compressed air supply for pulse-jet baghouses.
(3) An appropriate methodology for monitoring cleaning cycles to
ensure proper operation.
(4) Monthly check of bag cleaning mechanisms for proper functioning
through visual inspection or equivalent means.
(5) Quarterly visual check of bag tension on reverse air and
shaker-type baghouses to ensure that bags are not kinked (kneed or
bent) or laying on their sides. Such checks are not required for
shaker-type baghouses using self-tensioning (spring loaded) devices.
(6) Quarterly confirmation of the physical integrity of the
baghouse through visual inspection of the baghouse interior for air
leaks.
(7) Quarterly inspection of fans for wear, material buildup, and
corrosion through visual inspection, vibration detectors, or equivalent
means.
(8) Except as provided in paragraph (h) of this section, continuous
operation of a bag leak detection system.
(d) The procedures specified in the standard operating procedures
manual for maintenance must, at a minimum, include a preventative
maintenance schedule that is consistent with the baghouse
manufacturer's instructions for routine and long-term maintenance.
(e) The bag leak detection system required by paragraph (c)(8) of
this section must meet the specifications and requirements of (e)(1)
through (e)(8) of this section.
(1) The bag leak detection system must be certified by the
manufacturer to be capable of detecting particulate matter emissions at
concentrations of 10 milligram per actual cubic meter (0.0044 grains
per actual cubic foot) or less.
(2) The bag leak detection system sensor must provide output of
relative particulate matter loadings, and the owner or operator must
continuously record the output from the bag leak detection system.
(3) The bag leak detection system must be equipped with an alarm
system that will sound when an increase in relative particulate loading
is detected over a preset level, and the alarm must be located such
that it can be heard or otherwise determined by the appropriate plant
personnel.
(4) Each bag leak detection system that works based on the
triboelectric effect must be installed, calibrated, and maintained in a
manner consistent with guidance provided in the U.S. Environmental
Protection Agency guidance document ''Fabric Filter Bag Leak Detection
Guidance'' (EPA-454/R-98-015). Other bag leak detection systems must be
installed, calibrated, and maintained in a manner consistent with the
manufacturer's written specifications and recommendations.
(5) The initial adjustment of the system must, at a minimum,
consist of establishing the baseline output by adjusting the
sensitivity (range) and the averaging period of the device, and
establishing the alarm set points and the alarm delay time.
(6) Following initial adjustment, the owner or operator must not
adjust the sensitivity or range, averaging period, alarm set points, or
alarm delay time, except as detailed in the approved SOP required under
paragraph (a) of this
[[Page 9443]]
section. In no event shall the sensitivity be increased by more than
100 percent or decreased more than 50 percent over a 365-day period
unless a responsible official certifies that the baghouse has been
inspected and found to be in good operating condition.
(7) For negative pressure, induced air baghouses, and positive
pressure baghouses that are discharged to the atmosphere through a
stack, the bag leak detector must be installed downstream of the
baghouse and upstream of any wet acid gas scrubber.
(8) Where multiple detectors are required, the system's
instrumentation and alarm may be shared among detectors.
(f) The standard operating procedures manual required by paragraph
(a) of this section must include a corrective action plan that
specifies the procedures to be followed in the event of a bag leak
detection system alarm. The corrective action plan must include at a
minimum, procedures to be used to determine the cause of an alarm, as
well as actions to be taken to minimize emissions, which may include,
but are not limited to, the following.
(1) Inspecting the baghouse for air leaks, torn or broken bags or
filter media, or any other condition that may cause an increase in
emissions.
(2) Sealing off defective bags or filter media.
(3) Replacing defective bags or filter media, or otherwise
repairing the control device.
(4) Sealing off a defective baghouse compartment.
(5) Cleaning the bag leak detection system probe, or otherwise
repairing or maintaining the bag leak detection system.
(6) Shutting down the process producing the particulate emissions.
(g) The percentage of total operating time the alarm on the bag
leak detection system sounds in a 6-month reporting period must be
calculated in order to determine compliance with the five percent
operating limit in Sec. 63.1543(h). The percentage of time the alarm
on the bag leak detection system sounds must be determined according to
paragraphs (g)(1) through (g)(3) of this section.
(1) For each alarm where the owner or operator initiates procedures
to determine the cause of an alarm within 1 hour of the alarm, 1 hour
of alarm time must be counted.
(2) For each alarm where the owner or operator does not initiate
procedures to determine the cause of the alarm within 1 hour of the
alarm, alarm time will be counted as the actual amount of time taken by
the owner or operator to initiate procedures to determine the cause of
the alarm.
(3) The percentage of time the alarm on the bag leak detection
system sounds must be calculated as the ratio of the sum of alarm times
to the total operating time multiplied by 100.
(h) Baghouses equipped with HEPA filters as a secondary filter used
to control process or process fugitive sources subject to the lead
emission standards in Sec. 63.1543 are exempt from the requirement in
paragraph (c)(8) of this section to be equipped with a bag leak
detector. The owner or operator of an affected source that uses a HEPA
filter must monitor and record the pressure drop across the HEPA filter
system daily. If the pressure drop is outside the limit(s) specified by
the filter manufacturer, the owner or operator must take appropriate
corrective measures, which may include, but not be limited to, the
following:
(1) Inspecting the filter and filter housing for air leaks and torn
or broken filters.
(2) Replacing defective filter media, or otherwise repairing the
control device.
(3) Sealing off a defective control device by routing air to other
comparable control devices.
(4) Shutting down the process producing the particulate emissions.
(i) Owners and operators must monitor sinter machine building in-
draft to demonstrate continued compliance with the operating standard
specified in Sec. 63.1543(d) in accordance with either paragraph
(i)(1), (i)(2), or (i)(3) of this section.
(1) Owners and operators must check and record on a daily basis
doorway in-draft at each doorway in accordance with the methodology
specified in Sec. 63.1546(b).
(2) Owners and operators must establish and maintain baseline
ventilation parameters which result in a positive in-draft according to
paragraphs (i)(2)(i) through (i)(2)(iv) of this section.
(i) Owners and operators must install, calibrate, maintain, and
operate a monitoring device that continuously records the volumetric
flow rate through each separately ducted hood; or install, calibrate,
maintain, and operate a monitoring device that continuously records the
volumetric flow rate at the control device inlet of each exhaust system
ventilating the building. The flow rate monitoring device(s) can be
installed in any location in the exhaust duct such that reproducible
flow rate measurements will result. The flow rate monitoring device(s)
must have an accuracy of plus or minus 10 percent over the normal
process operating range and must be calibrated according to
manufacturer's instructions.
(ii) During the initial demonstration of sinter building in-draft,
and at any time the owner or operator wishes to re-establish the
baseline ventilation parameters, the owner or operator must
continuously record the volumetric flow rate through each separately
ducted hood, or continuously record the volumetric flow rate at the
control device inlet of each exhaust system ventilating the building
and record exhaust system damper positions. The owner or operator must
determine the average volumetric flow rate(s) corresponding to the
period of time the in-draft compliance determinations are being
conducted.
(iii) The owner or operator must maintain the volumetric flow
rate(s) at or above the value(s) established during the most recent in-
draft determination at all times the sinter machine is in operation.
Volumetric flow rate(s) must be calculated as a 15-minute average.
(iv) If the volumetric flow rate is monitored at the control device
inlet, the owner or operator must check and record damper positions
daily to ensure they are in the positions they were in during the most
recent in-draft determination.
(3) An owner or operator may request an alternative monitoring
method by following the procedures and requirements in Sec. 63.8(f) of
the General Provisions.
(j) Each owner or operator of new or modified sources listed under
Sec. 63.1543 (a)(1) through (a)(10) must install, calibrate, maintain,
and operate a continuous emission monitoring system (CEMS) for
measuring lead emissions and a continuous emission rate monitoring
system (CERMS) subject to Performance Specification 6 of Appendix B to
part 60.
(1) Each owner or operator of a source subject to the emissions
limits for lead compounds under Sec. 63.1543(a) and (b) must install a
CEMS for measuring lead emissions within 180 days of promulgation of
performance specifications for lead CEMS.
(i) Prior to promulgation of performance specifications for CEMS
used to measure lead concentrations, an owner or operator must use the
procedure described in Sec. 63.1546(a)(1) through (a)(7) of this
section to determine compliance.
(ii) [Reserved]
(2) If a CEMS used to measure lead emissions is applicable, the
owner or operator must install a CERMS with a sensor in a location that
provides representative measurement of the exhaust gas flow rate at the
sampling
[[Page 9444]]
location of the CEMS used to measure lead emissions, taking into
account the manufacturer's recommendations. The flow rate sensor is
that portion of the system that senses the volumetric flow rate and
generates an output proportional to that flow rate.
(i) The CERMS must be designed to measure the exhaust gas flow rate
over a range that extends from a value of at least 20 percent less than
the lowest expected exhaust flow rate to a value of at least 20 percent
greater than the highest expected exhaust gas flow rate.
(ii) The CERMS must be equipped with a data acquisition and
recording system that is capable of recording values over the entire
range specified in paragraph (b)(2)(i) of this section.
(iii) Each owner or operator must perform an initial relative
accuracy test of the CERMS in accordance with the applicable
Performance Specification in Appendix B to part 60 of the chapter.
(iv) Each owner or operator must operate the CERMS and record data
during all periods of operation of the affected facility including
periods of startup, shutdown, and malfunction, except for periods of
monitoring system malfunctions, repairs associated with monitoring
system malfunctions, and required monitoring system quality assurance
or quality control activities (including, as applicable, calibration
checks and required zero and span adjustments.
(3) Each owner or operator must calculate the lead emissions rate
in tons per year by summing all hours of CEMS data for a year to
determine compliance with 63.1543(b).
(i) When the CERMS are unable to provide quality assured data the
following applies:
(A) When data are not available for periods of up to 48 hours, the
highest recorded hourly emission rate from the previous 24 hours must
be used.
(B) When data are not available for 48 or more hours, the maximum
daily emission rate based on the previous 30 days must be used.
(ii) [Reserved]
(k) The owner or operator of each source subject to Sec.
63.1544(a) must operate a continuous monitoring system for the
measurement of lead compound concentrations in air.
(1) The owner or operator must operate compliance monitors
sufficient in number, location, and frequency of sample collection to
detect expected maximum concentrations of lead compounds in air due to
emissions from the affected source(s) in accordance with a written plan
as described in (k)(2) of this paragraph and approved by the
Administrator. The plan must include descriptions of the sampling and
analytical methods used. The plan may take into consideration existing
monitoring being conducted under a state monitoring plan in accordance
with part 58 of this chapter.
(2) The owner or operator must submit a written plan describing and
explaining the basis for the design and adequacy of the compliance
monitoring network, the sampling, analytical, and quality assurance
procedures, and any other related procedures, and the justification for
any seasonal, background, or other data adjustments within 45 days
after the effective date of this subpart.
(3) The Administrator at any time may require changes in, or
expansion of, the monitoring program, including additional sampling and
analytical protocols and network design.
(l) If all rolling three-month average concentrations of lead in
air measured by the compliance monitoring system are less than 50
percent of the lead concentration in air limit in Sec. 63.1544(a) for
three consecutive years, the owner or operator may submit a revised
plan to reduce the monitoring sampling and analysis frequency (e.g.,
from daily to weekly). For any subsequent period, if any rolling three-
month average lead concentration in air measured at any monitor in the
monitoring system exceeds 50 percent of the concentration limit in
Sec. 63.1544(a), the owner or operator must resume monitoring pursuant
to paragraph (k)(1) of this section at all monitors until another three
consecutive years of lead concentration in air measurements less than
50 percent of the lead concentration in air limit is demonstrated.
9. Section 63.1548 is revised to read as follows:
Sec. 63.1548 Notification requirements.
(a) The owner or operator of a primary lead processor must comply
with the notification requirements of Sec. 63.9 of subpart A, General
Provisions as specified in Table 1 of this subpart.
(b) The owner or operator of a primary lead processor must submit
the standard operating procedures manual for baghouses required under
Sec. 63.1547(a) to the Administrator or delegated authority along with
a notification that the primary lead processor is seeking review and
approval of the manual and procedures. Owners or operators of existing
primary lead processors must submit this notification no later than
November 6, 2000. The owner or operator of a primary lead processor
that commences construction or reconstruction after April 17, 1998,
must submit this notification no later than 180 days before startup of
the constructed or reconstructed primary lead processor, but no sooner
than September 2, 1999.
(c) The owner or operator of a primary lead processor must submit
the compliance monitoring network plan required under Sec.
63.1547(k)(2) to the Administrator or delegated authority along with a
notification that the primary lead processor is seeking review and
approval of the plan. Owners or operators of existing primary lead
processors must submit this notification no later than 45 days after
promulgation of this subpart. The owner or operator of a new,
reconstructed, or modified primary lead processor must submit this
notification no later than 180 days before startup of the constructed
or reconstructed primary lead processor.
10. Section 63.1549 is revised to read as follows:
Sec. 63.1549 Recordkeeping and reporting requirements.
(a) The owner or operator of a primary lead processor must comply
with the recordkeeping requirements of Sec. 63.10 of subpart A,
General Provisions as specified in Table 1 of this subpart.
(b) In addition to the general records required by paragraph (a) of
this section, each owner or operator of a primary lead processor must
maintain for a period of 5 years, records of the information listed in
paragraphs (b)(1) through (b)(10) of this section.
(1) Production records of the weight and lead content of lead
products, copper matte, and copper speiss.
(2) Records of the bag leak detection system output.
(3) An identification of the date and time of all bag leak
detection system alarms, the time that procedures to determine the
cause of the alarm were initiated, the cause of the alarm, an
explanation of the actions taken, and the date and time the cause of
the alarm was corrected.
(4) Any recordkeeping required as part of the requirements
described in the compliance monitoring system plan required under Sec.
63.1547(k)(2).
(5) Any recordkeeping required as part of the practices described
in the standard operating procedures manual for baghouses required
under Sec. 63.1547(a).
(6) If an owner or operator chooses to demonstrate continuous
compliance with the sinter building in-draft requirement under Sec.
63.1543(d) by employing the method allowed in Sec. 63.1547(i)(1), the
records of the daily doorway in-draft checks, an
[[Page 9445]]
identification of the periods when there was not a positive in-draft,
and an explanation of the corrective actions taken.
(7) If an owner or operator chooses to demonstrate continuous
compliance with the sinter building in-draft requirement under Sec.
63.1543(d) by employing the method allowed in Sec. 63.1547(i)(2), the
records of the output from the continuous volumetric flow monitor(s),
an identification of the periods when the 15-minute volumetric flow
rate dropped below the minimum established during the most recent in-
draft determination, and an explanation of the corrective actions
taken.
(8) If an owner or operator chooses to demonstrate continuous
compliance with the sinter building in-draft requirement under Sec.
63.1543(d) by employing the method allowed in Sec. 63.1547(i)(2), and
volumetric flow rate is monitored at the baghouse inlet, records of the
daily checks of damper positions, an identification of the days that
the damper positions were not in the positions established during the
most recent in-draft determination, and an explanation of the
corrective actions taken.
(9) Records of the occurrence and duration of each malfunction of
operation (i.e., process equipment) or the air pollution control
equipment and monitoring equipment.
(10) Records of actions taken during periods of malfunction to
minimize emissions in accordance with Sec. Sec. 63.1543(i) and
63.1544(e), including corrective actions to restore malfunctioning
process and air pollution control and monitoring equipment to its
normal or usual manner of operation.
(c) Records for the most recent 2 years of operation must be
maintained on site. Records for the previous 3 years may be maintained
off site.
(d) The owner or operator of a primary lead processor must comply
with the reporting requirements of Sec. 63.10 of subpart A, General
Provisions as specified in Table 1 of this subpart.
(e) In addition to the information required under Sec. 63.10 of
the General Provisions, the owner or operator must provide semi-annual
reports containing the information specified in paragraphs (e)(1)
through (e)(9) of this section to the Administrator or designated
authority.
(1) The reports must include records of all alarms from the bag
leak detection system specified in Sec. 63.1547(e).
(2) The reports must include a description of the actions taken
following each bag leak detection system alarm pursuant to Sec.
63.1547(f).
(3) The reports must include a calculation of the percentage of
time the alarm on the bag leak detection system sounded during the
reporting period pursuant to Sec. 63.1547(g).
(4) If an owner or operator chooses to demonstrate continuous
compliance with the sinter building in-draft requirement under Sec.
63.1543(d) by employing the method allowed in Sec. 63.1547(i)(1), the
reports must contain an identification of the periods when there was
not a positive in-draft, and an explanation of the corrective actions
taken.
(5) If an owner or operator chooses to demonstrate continuous
compliance with the sinter building in-draft requirement under Sec.
63.1543(d) by employing the method allowed in Sec. 63.1547(i)(2), the
reports must contain an identification of the periods when the 15-
minute volumetric flow rate(s) dropped below the minimum established
during the most recent in-draft determination, and an explanation of
the corrective actions taken.
(6) If an owner or operator chooses to demonstrate continuous
compliance with the sinter building in-draft requirement under Sec.
63.1543(d) by employing the method allowed in Sec. 63.1547(i)(2), and
volumetric flow rate is monitored at the baghouse inlet, the reports
must contain an identification of the days that the damper positions
were not in the positions established during the most recent in-draft
determination, and an explanation of the corrective actions taken.
(7) The reports must contain a summary of the records maintained as
part of the practices described in the standard operating procedures
manual for baghouses required under Sec. 63.1547(a), including an
explanation of the periods when the procedures were not followed and
the corrective actions taken.
(8) The reports must contain a summary of the compliance monitoring
results for the required reporting period, including an explanation of
any periods when the procedures outlined in the compliance monitoring
system plan required by Sec. 63.1547(k)(2) were not followed and the
corrective actions taken.
(9) If there was a malfunction during the reporting period, the
report shall also include the number, duration, and a brief description
for each type of malfunction which occurred during the reporting period
and which caused or may have caused any applicable emission limitation
to be exceeded. The report must also include a description of actions
taken by an owner or operator during a malfunction of an affected
source to minimize emissions in accordance with Sec. Sec. 63.1543(i)
and 63.1544(b), including actions taken to correct a malfunction.
11. Section 63.1550 is revised to read as follows:
Sec. 63.1550 Delegation of authority.
(a) In delegating implementation and enforcement authority to a
State under section 112(1) of the Act, the authorities contained in
paragraph (b) of this section must be retained by the Administrator and
not transferred to a State.
(b) Authorities which will not be delegated to States: No
restrictions.
12. Section 63.1551 is added to read as follows:
Sec. 63.1551 Affirmative defense for exceedance of emission limit
during malfunction.
In response to an action to enforce the standards set forth in this
subpart you may assert an affirmative defense to a claim for civil
penalties for exceedances of such standards that are caused by
malfunction, as defined in 40 CFR 63.2. Appropriate penalties may be
assessed, however, if you fail to meet your burden of proving all the
requirements in the affirmative defense. The affirmative defense shall
not be available for claims for injunctive relief.
(a) To establish the affirmative defense in any action to enforce
such a limit, you must timely meet the notification requirements in
paragraph (b) of this section, and must prove by a preponderance of
evidence that:
(1) The excess emissions:
(i) Were caused by a sudden, short, infrequent, and unavoidable
failure of air pollution control and monitoring equipment, process
equipment, or a process to operate in a normal or usual manner; and
(ii) Could not have been prevented through careful planning, proper
design or better operation and maintenance practices; and
(iii) Did not stem from any activity or event that could have been
foreseen and avoided, or planned for; and
(iv) Were not part of a recurring pattern indicative of inadequate
design, operation, or maintenance; and
(2) Repairs were made as expeditiously as possible when the
applicable emission limitations were being exceeded. Off-shift and
overtime labor were used, to the extent practicable to make these
repairs; and
(3) The frequency, amount and duration of the excess emissions
(including any bypass) were minimized to the maximum extent practicable
during periods of such emissions; and
[[Page 9446]]
(4) If the excess emissions resulted from a bypass of control
equipment or a process, then the bypass was unavoidable to prevent loss
of life, severe personal injury, or severe property damage; and
(5) All possible steps were taken to minimize the impact of the
excess emissions on ambient air quality, the environment and human
health; and
(6) All emissions monitoring and control systems were kept in
operation if at all possible; and
(7) All of the actions in response to the excess emissions were
documented by properly signed, contemporaneous operating logs; and
(8) At all times, the facility was operated in a manner consistent
with good practices for minimizing emissions; and
(9) A written root cause analysis has been prepared to determine,
correct and eliminate the primary causes of the malfunction and the
excess emissions resulting from the malfunction event at issue. The
analysis shall also specify, using best monitoring methods and
engineering judgment, the amount of excess emissions that were the
result of the malfunction.
(b) Notification. The owner or operator of the facility
experiencing an exceedance of its emission limit(s) during a
malfunction shall notify the Administrator by telephone or facsimile
(FAX) transmission as soon as possible, but no later than two business
days after the initial occurrence of the malfunction, if it wishes to
avail itself of an affirmative defense to civil penalties for that
malfunction. The owner or operator seeking to assert an affirmative
defense shall also submit a written report to the Administrator within
30 days of the initial occurrence of the exceedance of the standard in
this subpart to demonstrate, with all necessary supporting
documentation, that it has met the requirements set forth in paragraph
(a) of this section.
12. Table 1 to Subpart TTT of Part 63 is revised to read as
follows:
Table 1 to Subpart TTT of Part 63--General Provisions Applicability to Subpart TTT
----------------------------------------------------------------------------------------------------------------
Reference Applies to subpart TTT Explanation
----------------------------------------------------------------------------------------------------------------
Sec. 63.1....................... Yes. .............................................
Sec. 63.2....................... Yes. .............................................
Sec. 63.3....................... Yes. .............................................
Sec. 63.4....................... Yes. .............................................
Sec. 63.5....................... Yes. .............................................
Sec. 63.6(a), (b), (c).......... Yes. .............................................
Sec. 63.6 (d)................... No........................... Section reserved.
Sec. 63.6(e)(1)(i).............. No........................... See Sec. 63.1543(i) and Sec. 63.1544(b)
for general duty requirement.
Sec. 63.6(e)(1)(ii)............. No. .............................................
Sec. 63.6(e)(1)(iii)............ Yes. .............................................
Sec. 63.6(e)(2)................. No........................... Section reserved.
Sec. 63.6(e)(3)................. No. .............................................
Sec. 63.6(f)(1)................. No. .............................................
Sec. 63.6(g).................... Yes. .............................................
Sec. 63.6(h).................... No........................... No opacity limits in rule.
Sec. 63.6(i).................... Yes. .............................................
Sec. 63.6(j).................... Yes. .............................................
Sec. 63.7(a)-(d)................ Yes. .............................................
Sec. 63.7(e)(1)................. No........................... See Sec. 63.1546(c).
Sec. 63.7(e)(2)-(e)(4).......... Yes. .............................................
Sec. 63.7(f), (g), (h).......... Yes. .............................................
Sec. 63.8(a)-(b)................ Yes. .............................................
Sec. 63.8(c)(1)(i).............. No. .............................................
Sec. 63.8(c)(1)(ii)............. Yes. .............................................
Sec. 63.8(c)(1)(iii)............ No. .............................................
Sec. 63.8(c)(2)-(d)(2).......... Yes. .............................................
Sec. 63.8(d)(3)................. Yes, except for last .............................................
sentence.
Sec. 63.8(e)-(g)................ Yes. .............................................
Sec. 63.9(a), (b), (c), (e), Yes. .............................................
(g), (h)(1) through (3), (h)(5)
and (6), (i) and (j).
Sec. 63.9(f).................... No. .............................................
Sec. 63.9(h)(4)................. No........................... Reserved.
Sec. 63.10(b)(2)(i)............. No. .............................................
Sec. 63.10(b)(2)(ii)............ No........................... See Sec. 63.1549(b)(9) and (10) for
recordkeeping of occurrence and duration of
malfunctions and recordkeeping of actions
taken during malfunction.
Sec. 63.10(b)(2)(iii)........... Yes. .............................................
Sec. 63.10(b)(2)(iv)-(b)(2)(v).. No. .............................................
Sec. 63.10(b)(2)(vi)-(b)(2)(xiv) Yes. .............................................
Sec. 63.(10)(b)(3).............. Yes. .............................................
Sec. 63.10(c)(1)-(9)............ Yes. .............................................
Sec. 63.10(c)(10)-(11).......... No........................... See Sec. 63.1549(b)(9) and (10) for
recordkeeping of malfunctions.
Sec. 63.10(c)(12)-(c)(14)....... Yes. .............................................
Sec. 63.10(c)(15)............... No. .............................................
Sec. 63.10(d)(1)-(4)............ Yes. .............................................
[[Page 9447]]
Sec. 63.10(d)(5)................ No........................... See Sec. 63.1549(e)(9) for reporting of
malfunctions.
Sec. 63.10(e)-((f).............. Yes. .............................................
Sec. 63.11...................... No........................... Flares will not be used to comply with the
emission limits.
Sec. 63.12 through 63.15........ Yes. .............................................
----------------------------------------------------------------------------------------------------------------
[FR Doc. 2011-2866 Filed 2-16-11; 8:45 am]
BILLING CODE 6560-50-P