[Federal Register Volume 76, Number 226 (Wednesday, November 23, 2011)]
[Proposed Rules]
[Pages 72507-72558]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-29455]
[[Page 72507]]
Vol. 76
Wednesday,
No. 226
November 23, 2011
Part II
Environmental Protection Agency
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40 CFR Part 63
National Emissions Standards for Hazardous Air Pollutants: Ferroalloys
Production; Proposed Rule
Federal Register / Vol. 76 , No. 226 / Wednesday, November 23, 2011 /
Proposed Rules
[[Page 72508]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 63
[EPA-HQ-OAR-2010-0895; FRL-9491-8]
RIN 2060-AQ-11
National Emissions Standards for Hazardous Air Pollutants:
Ferroalloys Production
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: The EPA is proposing amendments to the national emissions
standards for hazardous air pollutants for Ferroalloys Production to
address the results of the residual risk and technology review that the
EPA is required to conduct under the Clean Air Act. These proposed
amendments include revisions to particulate matter standards for
electric arc furnaces, metal oxygen refining processes, and crushing
and screening operations. The amendments also add emission limits for
hydrochloric acid, mercury, polycyclic aromatic hydrocarbons, and
formaldehyde from electric arc furnaces. Furthermore, the amendments
expand and revise the requirements to control fugitive emissions from
furnace operations and casting. Other proposed requirements related to
testing, monitoring, notification, recordkeeping, and reporting are
included. We are also proposing to revise provisions addressing periods
of startup, shutdown, and malfunction to ensure that the rules are
consistent with a recent court decision.
DATES: Comments must be received on or before January 9, 2012. 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 December 23, 2011.
Public Hearing. If anyone contacts the EPA requesting to speak at a
public hearing by December 5, 2011, a public hearing will be held on
December 8, 2011.
ADDRESSES: Submit your comments, identified by Docket ID Number EPA-HQ-
OAR-2010-0895, by one of the following methods:
http://www.regulations.gov: Follow the on-line
instructions for submitting comments.
Email: a-and-r-docket@epa.gov, Attention Docket ID Number
EPA-HQ-OAR-2010-0895.
Fax: (202) 566-9744, Attention Docket ID Number EPA-HQ-
OAR-2010-0895.
Mail: U.S. Postal Service, send comments to: EPA Docket
Center, EPA West (Air Docket), Attention Docket ID Number EPA-HQ-OAR-
2010-0895, 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-2010-0895. 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-
2010-0895. The 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 email. The http://www.regulations.gov Web site
is an ``anonymous access'' system, which means the EPA will not know
your identity or contact information unless you provide it in the body
of your comment. If you send an email comment directly to the EPA
without going through http://www.regulations.gov, your email 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, the 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 the EPA cannot read your comment
due to technical difficulties and cannot contact you for clarification,
the 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 the
EPA's public docket, visit the EPA Docket Center homepage at epa.gov/epahome/dockets.htm.
Docket. The EPA has established a docket for this rulemaking under
Docket ID Number EPA-HQ-OAR-2010-0895. All documents in the docket are
listed in the 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 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 December 8, 2011 and will be held at the 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 (OAQPS), Sector
Policies and Programs Division, (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 Mr. Conrad Chin, 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) 541-1512; fax number: (919) 541-3207; and email
address: chin.conrad@epa.gov. For specific information regarding the
risk modeling methodology, contact Ms. Darcie Smith, 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) 541-2076;
fax number: (919) 541-0840; and email address: smith.darcie@epa.gov.
For information about the applicability of the National Emissions
Standards for
[[Page 72509]]
Hazardous Air Pollutants (NESHAP) to a particular entity, contact the
appropriate person listed in Table 1 of this preamble.
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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Ferroalloys Production...... Cary Secrest, (202) Conrad Chin, (919)
564-8661 541-1512,
secrest.cary@epa.go chin.conrad@epa.gov
v. .
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\1\ EPA Office of Enforcement and Compliance Assurance.
\2\ EPA Office of Air Quality Planning and Standards.
SUPPLEMENTARY INFORMATION:
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:
ACI Activated Carbon Injection
ADAF age-dependent adjustment factors
AEGL acute exposure guideline levels
AERMOD air dispersion model used by the HEM-3 model
ATSDR Agency for Toxic Substances and Disease Registry
BLDS bag leak detection system
BPT benefit-per-ton
CAA Clean Air Act
CalEPA California EPA
CBI Confidential Business Information
CFR Code of Federal Regulations
CIIT Chemical Industry Institute of Toxicology
CO2 carbon dioxide
EJ environmental justice
EPA Environmental Protection Agency
ERPG Emergency Response Planning Guidelines
ERT Electronic Reporting Tool
FR Federal Register
gr/dscf grains per dry standard cubic foot
HAP hazardous air pollutants
HCl hydrochloric acid
HEM-3 Human Exposure Model, Version 1.1.0
HI Hazard Index
HON hazardous organic national emissions standards for hazardous air
pollutants
HQ Hazard Quotient
ICR information collection request
IRIS Integrated Risk Information System
kg/hr kilograms per hour
kg/hr/MW kilograms per hour per megawatt
km kilometer
lb/hr pounds per hour
lb/hr/MW pounds per hour per megawatt
lb/yr pounds per year
LML lowest measured level
MACT maximum achievable control technology
MACT Code Code within the National Emissions Inventory used to
identify processes included in a source category
MDL method detection limit
mg/dscm milligrams per dry standard cubic meter
MIR maximum individual risk
MM millions
MW megawatt
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
NRC National Research Council
NTTAA National Technology Transfer and Advancement Act
OAQPS Office of Air Quality Planning and Standards
OECA Office of Enforcement and Compliance Assurance
OMB Office of Management and Budget
PAH polycyclic aromatic hydrocarbons
PB-HAP hazardous air pollutants known to be persistent and bio-
accumulative in the environment
PM particulate matter
POM polycyclic organic matter
QA quality assurance
RCRA Resource Conservation and Recovery Act
RDL representative detection level
REL reference exposure level
RFA Regulatory Flexibility Act
RfC reference concentration
RfD reference dose
RIA Regulatory Impact Analysis
RTR residual risk and technology review
SAB Science Advisory Board
SBA Small Business Administration
SOP standard operating procedures
SSM startup, shutdown, and malfunction
TOSHI target organ-specific hazard index
TPY tons per year
TRIM.FaTE Total Risk Integrated Methodology.Fate, Transport, and
Ecological Exposure model
TTN Technology Transfer Network
UF uncertainty factor
[mu]g/m\3\ microgram per cubic meter
UMRA Unfunded Mandates Reform Act
UPL upper predictive limit
URE unit risk estimate
VCS voluntary consensus standards
WWW world wide web
Organization of this Document. The information in this preamble is
organized as follows:
I. General Information
A. Summary of Costs and Benefits
B. What are NESHAP?
C. Does this action apply to me?
D. Where can I get a copy of this document and other related
information?
E. What should I consider as I prepare my comments for the EPA?
II. Background
A. What is this source category and how did the 1999 MACT
standards regulate its HAP emissions?
B. What data collection activities were conducted to support
this action?
C. What other relevant background information from previous
studies on ferroalloys emissions is available?
III. Analyses Performed
A. How did we address unregulated emissions sources?
B. How did we estimate risks posed by the source category?
C. How did we consider the risk results in making decisions for
this proposal?
D. How did we perform the technology review?
E. What other issues are we addressing in this proposal?
IV. Analytical Results and Proposed Decisions
A. What are the results of our analyses and proposed decisions
regarding unregulated pollutants?
B. What are the results of the risk assessment and analyses?
C. What are our proposed decisions based on risk acceptability
and ample margin of safety?
D. What are the results and proposed decisions based on our
technology review?
E. What other actions are we proposing?
F. What compliance dates are we proposing?
V. Summary of Cost, Environmental, and Economic Impacts
A. What are the affected sources?
B. What are the air quality impacts?
C. What are the cost impacts?
D. What are the economic impacts?
E. What are the benefits?
F. What demographic groups might benefit from this regulation?
VI. Request for Comments
VII. Submitting Data Corrections
VIII. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulation and Regulatory 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
[[Page 72510]]
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
I. General Information
A. Summary of Costs and Benefits
Consistent with the recently issued Executive Order 13563,
``Improving Regulation and Regulatory Review,'' we have estimated the
costs and benefits of the proposed rule. The estimated net benefits of
the proposed rule at a 3 percent discount rate are $67 to $170 million
or $59 to $150 million at a 7 percent discount rate. The monetized
benefits in this analysis are due to PM2.5 co-benefits, as
HAP benefits are not monetized. Table 2 presents a summary of the
results of the analysis.
Table 2--Summary of the Estimated Annual Monetized Benefits, Social
Costs, and Net Benefits for the Proposed Rule in 2015
[Millions of 2010$] a
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3% Discount rate 7% Discount rate
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Total Monetized Benefits b.. $71 to $170......... $63 to $160.
Total Social Costs c........ $4.0................ $4.0.
Net Benefits................ $67 to $170......... $59 to $150.
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Non-monetized Benefits...... Reduced exposure to Hazardous Air
Pollutants (HAP), including Manganese,
polycyclic aromatic hydrocarbons (PAH),
Chromium, Arsenic, Nickel, and Mercury.
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a All estimates are for implementation year 2015 (the benefit estimates
use 2016 values as an approximation); and are rounded to two
significant figures so numbers may not sum across columns. All fine
particles are assumed to have equivalent health effects, but the
benefit-per-ton (BPT) estimates vary because each ton of precursor
reduced has a different propensity to become particulate matter
(PM)2.5. These benefits incorporate the conversion from precursor
emissions to ambient fine particles. The BPT estimates are based on
recent air quality modeling specific to the ferroalloys sector.
b All estimates are for 2016, which we use as an approximation for
impacts in 2015.
c The compliance costs of the proposal serve as a proxy for the social
costs. The compliance costs are estimated using a 7% interest rate.
Under the proposed amendments, ferroalloys production facilities
are expected to incur $11.4 million in capital costs to install new air
pollution controls and new or improved monitoring systems. We have
estimated the annualized costs to be $4.0 million, which includes
estimated monitoring and testing costs. Section V.C of this preamble
contains more detail on these estimated cost impacts.
B. What are NESHAP?
1. 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 HAP from stationary sources.
In the first stage, after the EPA has identified categories of sources
emitting one or more of the HAP listed in CAA section 112(b), CAA
section 112(d) calls for us to promulgate national technology-based
emission standards for hazardous air pollutants (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 emissions reductions of
HAP achievable (after considering cost, energy requirements, and nonair
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 emissions
reduction achievable through the application of measures, processes,
methods, systems, or techniques, including, but not limited to,
measures that (1) Reduce the volume of or eliminate pollutants through
process changes, substitution of materials or other modifications; (2)
enclose systems or processes to eliminate emissions; (3) capture or
treat pollutants when released from a process, stack, storage, or
fugitive emissions point; (4) are design, equipment, work practice, or
operational standards (including requirements for operator training or
certification); or (5) 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 the EPA first
determines either that, (1) 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 (2) 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 emissions control that is achieved in practice by
the best-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 five 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 considerations 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 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, the EPA is not obliged to completely recalculate the prior MACT
determination. NRDC v. EPA, 529 F.3d 1077, 1084 (DC Cir., 2008).
The second stage in standard-setting focuses on reducing any
remaining (i.e., ``residual'') risk according to CAA section 112(f).
This provision requires, first, that the EPA prepare a Report to
Congress discussing (among other things) methods of calculating the
risks
[[Page 72511]]
posed (or potentially posed) by sources after implementation of the
MACT standards, the public health significance of those risks, and the
EPA's recommendations as to legislation regarding such remaining risk.
The 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 the EPA's obligation under
CAA section 112(f)(2) to analyze and address residual risk.
CAA section 112(f)(2) requires us to determine for source
categories subject to certain MACT standards, whether those emissions
standards provide an ample margin of safety to protect public health.
If the MACT standards for HAP ``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,'' the 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. In doing so, the EPA may adopt standards equal
to existing MACT standards if the EPA determines that the existing
standards are sufficiently protective. NRDC v. EPA, 529 F.3d 1077, 1083
(DC Cir. 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.'')
The EPA must also adopt more stringent standards, if necessary, to
prevent an adverse environmental effect,\1\ but must consider cost,
energy, safety and other relevant factors in doing so.
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\1\ ``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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Section 112(f)(2) of the CAA expressly preserves 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 Emissions 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 Federal Register (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 to be set (unless an even more stringent standard is
necessary 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 EPA's interpretation
set out in the Benzene NESHAP, and the United States Court of Appeals
for the District of Columbia Circuit in NRDC v. EPA, 529 F.3d 1077,
concluded that the EPA's interpretation of subsection 112(f)(2) is a
reasonable one. See NRDC v. EPA, 529 F.3d at 1083 (DC Cir. 2008), which
says ``[S]ubsection 112(f)(2)(B) expressly incorporates the 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 also 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, the EPA
does not define ``rigid line[s] of acceptability,'' but rather
considers 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 one in 10 thousand, that risk level is considered
acceptable.'' 54 FR 38045. We discussed the maximum individual lifetime
cancer risk (or maximum individual risk (MIR)) 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 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 one million (one 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. Further, in the Benzene
NESHAP, we noted that, ``Particular attention will also be accorded to
the weight of evidence presented in the risk assessment of potential
carcinogenicity or other health effects of a pollutant. While the same
numerical risk may be estimated for an exposure to a pollutant judged
to be a known human carcinogen, and to a pollutant considered a
possible human carcinogen based on limited animal test data, the same
weight cannot be accorded to both estimates. In considering the
potential public health effects of the two pollutants, the Agency's
judgment on acceptability,
[[Page 72512]]
including the MIR, will be influenced by the greater weight of evidence
for the known human carcinogen.'' Id. at 38046.
The Agency also explained in the 1989 Benzene NESHAP the following:
``In establishing a presumption for MIR, 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-emissions 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 * * *. 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 section 112.''
In NRDC v. EPA, 529 F.3d 1077, 1082 (DC Cir. 2008), the Court of
Appeals held that section 112(f)(2) ``incorporates EPA's
`interpretation' of the Clean Air Act from the Benzene Standard, and
the text of this provision draws no distinction between carcinogens and
non-carcinogens.'' Additionally, the Court held there is nothing on the
face of the statute that limits the Agency's section 112(f) assessment
of risk to carcinogens. Id. at 1081-82. In the NRDC case, the
petitioners argued, among other things, that section 112(f)(2)(B)
applied only to non-carcinogens. The DC Circuit rejected this position,
holding that the text of that provision ``draws no distinction between
carcinogens and non-carcinogens,'' id., and that Congress'
incorporation of the Benzene standard applies equally to carcinogens
and non-carcinogens.
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.
2. How do we consider the risk results in making decisions?
As discussed in the previous section of this preamble, we apply a
two-step process for developing standards to address residual risk. In
the first step, the 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) \2\ of approximately one in 10
thousand [i.e., 100 in one million].'' 54 FR 38045. In the second step
of the process, the 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 one in one 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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\2\ 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 determinations, the EPA presented 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 noncancer hazard index (HI);
and the maximum acute noncancer hazard. In estimating risks, the EPA
considered sources under review that are located near each other and
that affect the same population. The EPA developed risk estimates based
on the actual emissions from the source category under review as well
as based on the maximum emissions allowed pursuant to the source
category MACT standard. The EPA also discussed and considered risk
estimation uncertainties. The EPA is providing this same type of
information in support of these actions.
The Agency acknowledges that the Benzene NESHAP provides
flexibility regarding what factors the EPA might consider in making our
determinations and how they might be weighed for each source category.
In responding to comment on our policy under the Benzene NESHAP, the
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 noncancer
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.' ''
For example, the level of the MIR is only one factor to be weighed
in determining acceptability of risks. The Benzene NESHAP explains ``an
MIR of approximately one 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.'' Similarly, with regard to the
ample margin of safety analysis, the Benzene NESHAP states 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
[[Page 72513]]
and economic factors (along with the health-related factors) vary from
source category to source category.''
C. Does this action apply to me?
The regulated industrial source category that is the subject of
this proposal is listed in Table 3. Table 3 of this preamble is not
intended to be exhaustive, but rather provides a guide for readers
regarding the entities likely to be affected by this proposed action.
The proposed standards, once finalized, will be directly applicable to
affected sources. Federal, state, local, and tribal government entities
are not affected by this proposed action. As defined in the MACT (major
source) source category listing report published by the EPA in 1992,
the ``Ferroalloys Production'' source category is any facility engaged
in producing ferroalloys such as ferrosilicon, ferromanganese, and
ferrochrome.\3\ Subsequently, the EPA redefined the MACT source
category when it promulgated the Ferroalloy MACT standard so that it
now includes only major sources that produce products containing
manganese. (64 FR 27450, May 20, 1999) The MACT standard applies
specifically to two ferroalloy product types: ferromanganese and
silicomanganese.
---------------------------------------------------------------------------
\3\ EPA. Documentation for Developing the Initial Source
Category List--Final Report, EPA/OAQPS, EPA-450/3-91-030, July,
1992.
Table 3--NESHAP and Industrial Source Categories Affected by This Proposed Action
----------------------------------------------------------------------------------------------------------------
Source category NESHAP NAICS code \1\ MACT code \2\
----------------------------------------------------------------------------------------------------------------
Ferroalloys Production........................ Ferroalloys Production.......... 331112 0304
----------------------------------------------------------------------------------------------------------------
\1\ North American Industry Classification System.
\2\ Maximum Achievable Control Technology.
D. 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 EPA's 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. Supporting documents and
other relevant information including a version of the regulatory text
showing specific proposed changes is located in the docket (EPA-HQ-OAR-
2010-0895).
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 estimates and other data that were used as inputs to
the risk assessment.
E. What should I consider as I prepare my comments for the EPA?
Submitting CBI. Do not submit information containing CBI to the EPA
through http://www.regulations.gov or email. 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 the 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 comments that includes information claimed
as CBI, a copy of the comments 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 the 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 Code of Federal Regulations (CFR) part 2. Send or deliver
information identified as CBI only to the following address: Roberto
Morales, OAQPS Document Control Officer (C404-02), OAQPS, U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina
27711, Attention Docket ID Number EPA-HQ-OAR-2010-0895.
II. Background
A. What is this source category and how did the 1999 MACT standards
regulate its HAP emissions?
The NESHAP (or MACT rule) for Ferroalloys Production:
Ferromanganese and Silicomanganese was promulgated on May 20, 1999 (64
FR 27450) and codified at 40 CFR part 63, subpart XXX.\4\ The 1999
NESHAP applies to all new and existing ferroalloys production
facilities that manufacture ferromanganese or silicomanganese and are
major sources or are co-located at major sources of HAP emissions. The
rule's product-specific applicability reflected the fact that there was
only one known major source within the Ferroalloys Production source
category at the time of promulgation. Since then, one other major
source of silicomanganese has started production, but it was permitted
as an existing source.
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\4\ The emission limits were revised on March 22, 2001 (66 FR
16024) in response to a petition for reconsideration submitted to
the EPA following promulgation of the final rule, and a petition for
review filed in the U.S. Court of Appeals for the District of
Columbia Circuit.
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Today, there are two ferroalloys production facilities subject to
the MACT rule. No greenfield manganese ferroalloys production
facilities have been built in over 20 years, and we anticipate no
greenfield manganese ferroalloys production facilities in the
foreseeable future, although one facility is currently exploring
expanding operations through the addition of a new furnace.
Ferroalloys are alloys of iron in which one or more chemical
elements (such as chromium, manganese, and silicon) are added into
molten metal. Ferroalloys are consumed primarily in iron and steel
making and are used to produce steel and cast iron products with
enhanced or special properties.
Ferroalloys within the scope of this source category are produced
using submerged electric arc furnaces, which are furnaces in which the
electrodes are submerged into the charge. The submerged arc process is
a reduction smelting operation. The reactants consist of metallic ores
(ferrous oxides, silicon oxides, manganese oxides, etc.) and a carbon-
source reducing agent, usually in the form of coke, charcoal, high- and
low-volatility coal, or wood chips. Raw materials are crushed and
sized, and then conveyed to a mix house for weighing and blending.
Conveyors, buckets, skip hoists, or cars transport the processed
material to hoppers above the furnace. The mix is gravity-fed
[[Page 72514]]
through a feed chute either continuously or intermittently, as needed.
At high temperatures in the reaction zone, the carbon source reacts
with metal oxides to form carbon monoxide and to reduce the ores to
base metal.\5\ The molten material (product and slag) is tapped from
the furnace, sometimes subject to post-furnace refining, and poured
into casting beds on the furnace room floor. Once the material hardens,
it is transported to product crushing and sizing systems and packaged
for transport to the customer.
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\5\ EPA. AP-42, 12.4. Ferroalloy Production. 10/86.
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HAP generating processes include electrometallurgical (furnace)
operations (smelting and tapping), other furnace room operations (ladle
treatment and casting), building fugitives, raw material handling and
product handling. HAP are emitted from ferroalloys production as
process emissions, process fugitive emissions, and outdoor fugitive
dust emissions.
Process emissions are the exhaust gases from the control devices,
primarily the furnace control device, metal oxygen refining control
device and crushing operations control device. The HAP in process
emissions are primarily composed of metals (mostly manganese, arsenic,
nickel, lead, mercury and chromium) and also may include organic
compounds that result from incomplete combustion of coal, coke or other
fuel that is charged to the furnaces as a reducing agent. There are
also process metal HAP emissions from the product crushing control
devices. Process fugitive emissions occur at various points during the
smelting process (such as during charging and tapping of furnaces and
casting) and are assumed to be similar in composition to the process
emissions. Outdoor fugitive dust emissions result from the entrainment
of HAP in ambient air due to material handling, vehicle traffic, wind
erosion from storage piles, and other various activities. Outdoor
fugitive dust emissions are composed of particulate metal HAP only.
The MACT rule applies to process emissions from the submerged arc
furnaces, the metal oxygen refining process, and the product crushing
equipment, process fugitive emissions from the furnace and outdoor
fugitive dust emissions sources such as roadways, yard areas, and
outdoor material storage and transfer operations. For process sources,
the NESHAP specifies numerical emissions limits for particulate matter
(as a surrogate for non-mercury (or particulate) metal HAP) from the
electric (submerged) arc furnaces (including smelting and tapping
emissions), with the specific limits depending on furnace type, size,
and product being made. Particulate matter emission limits (again as a
surrogate for particulate metal HAP) are also in place for process
emissions from the metal oxygen refining process and product crushing
and screening equipment. Table 4 is a summary of the applicable limits.
Table 4--Emission Limits in Subpart XXX
----------------------------------------------------------------------------------------------------------------
Applicable PM
New or reconstructed or Affected source emission Subpart XXX reference
existing source standards
----------------------------------------------------------------------------------------------------------------
New or reconstructed.......... Submerged arc furnace........... 0.23 kilograms 40 CFR 63.1652(a)(1) and
per hour per (a)(2)
megawatt (kg/hr/
MW) (0.51 pounds
per hour per
megawatt (lb/hr/
MW) or 35
milligrams per
dry standard
cubic meter (mg/
dscm) (0.015
grains per dry
standard cubic
foot (gr/dscf).
Existing...................... Open submerged arc furnace 9.8 kg/hr (21.7 40 CFR 63.1652(b)(1)
producing ferromanganese and lb/hr).
operating at a furnace power
input of 22 megawatts (MW) or
less.
Existing...................... Open submerged arc furnace 13.5 kg/hr (29.8 40 CFR 63.1652(b)(2)
producing ferromanganese and lb/hr).
operating at a furnace power
input greater than 22 MW.
Existing...................... Open submerged arc furnace 16.3 kg/hr (35.9 40 CFR 63.1652(b)(3)
producing silicomanganese and lb/hr).
operating at a furnace power
input greater than 25 MW.
Existing...................... Open submerged arc furnace 12.3 kg/hr (27.2 40 CFR 63.1652(b)(4)
producing silicomanganese and lb/hr).
operating at a furnace power
input of 25 MW or less.
Existing...................... Semi-sealed submerged arc 11.2 kg/hr (24.7 40 CFR 63.1652(c)
furnace (primary, tapping, and lb/hr).
vent stacks) producing
ferromanganese.
New, reconstructed, or Metal oxygen refining process... 69 mg/dscm (0.03 40 CFR 63.1652(d)
existing. gr/dscf).
New or reconstructed.......... Individual equipment associated 50 mg/dscm (0.022 40 CFR 63.1652(e)(1)
with the product crushing and gr/dscf).
screening operation.
Existing...................... Individual equipment associated 69 mg/dscm (0.03 40 CFR 63.1652(e)(2)
with the product crushing and gr/dscf).
screening operation.
----------------------------------------------------------------------------------------------------------------
The 1999 NESHAP established a building opacity limit of 20 percent
that is measured during the required furnace control device performance
test. The rule provides an excursion limit of 60 percent opacity for
one 6-minute period during the performance test. The opacity
observation is focused only on emissions exiting the shop due solely to
operations of any affected submerged arc furnace. In addition, blowing
taps, poling and oxygen lancing of the tap hole; burndowns associated
with electrode measurements; and maintenance activities associated with
submerged arc furnaces and casting operations are exempt from the
opacity standards specified in Sec. 63.1653.
[[Page 72515]]
For outdoor fugitive dust sources, as defined in Sec. 63.1652, the
1999 NESHAP requires that plants prepare and operate according to an
outdoor fugitive dust control plan that describes in detail the
measures that will be put in place to control outdoor fugitive dust
emissions from the individual outdoor fugitive dust sources at the
facility. The owner or operator must submit a copy of the outdoor
fugitive dust control plan to the designated permitting authority on or
before the applicable compliance date.
B. What data collection activities were conducted to support this
action?
In April 2010, we issued an information collection request (ICR),
pursuant to CAA section 114, to the two companies that own and operate
the two known ferroalloys production facilities producing
ferromanganese and silicomanganese. The ICR requested available
information regarding process equipment, control devices, point and
fugitive emissions, practices used to control fugitive emissions, and
other aspects of facility operations. The two companies completed the
surveys for their facilities and submitted the responses to us in the
fall of 2010. We also requested that the two facilities conduct
additional emissions tests in 2010 for certain HAP from specific
processes that were considered representative of the industry.
Additional emissions testing was performed for most HAP metals (e.g.,
manganese, arsenic, chromium, lead, nickel and mercury), hydrochloric
acid (HCl), formaldehyde, and PAH. The results of these tests were
submitted to the EPA in the fall of 2010 and are available in the
docket for this action.
During the development of this regulation we discovered other types
of ferroalloys production facilities (e.g., non-manganese ferroalloy
production) that are not subject to this NESHAP. We plan to gather
additional information on these other types of sources, and then
evaluate whether we need to establish MACT standards for these sources.
C. What other relevant background information from previous studies on
ferroalloys emissions is available?
In addition to the emissions information and risk assessment
described in this preamble, other sources of publicly available data
exist. Based on historical emissions data from the EPA's Toxics Release
Inventory, one of the manganese ferroalloys facilities in this source
category \6\ has been one of the highest-emitters of manganese in the
country for at least 15 years (http://www.epa.gov/enviro/facts/tri/index.html). Several agencies have conducted studies of the emissions
from this facility and potential health effects of those emissions.
---------------------------------------------------------------------------
\6\ Eramet Marrietta, located in Marietta, Ohio.
---------------------------------------------------------------------------
The Agency for Toxic Substances and Disease Registry (ATSDR), of
the U.S. Department of Health and Human Services, along with the Ohio
Department of Health and the Ohio Environmental Protection Agency
conducted two health consultations in the communities surrounding this
manganese ferroalloys facility between 2004 and 2007. The
investigations found average ambient concentrations of manganese at
levels higher than background concentrations and higher than health
benchmark concentrations. More information about these studies can be
found at http://www.atsdr.cdc.gov/sites/washington_marietta/index.html.
As a result of these findings, a health study of chronic adult
exposure to ambient manganese in the communities surrounding the
facility was funded by the EPA. Available results show no significant
differences in blood manganese concentrations or major health outcomes
between residents living near the facility and residents in a
comparison town; however some subtle, subclinical motor (movement)
differences were found in residents in the town with the facility.\7\
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\7\ In press: Kim Y et al. Motor function in adults of an Ohio
community with environmental manganese exposure. 2011
Neurotoxicology, doi: 10.1016/j. neuro.2011.07.011.
---------------------------------------------------------------------------
In addition, under the EPA's School Air Toxics Initiative, ambient
concentrations of manganese were monitored at three schools located
near the ferroalloys production facility in late 2009. At these
locations, mean manganese concentrations above the health benchmark
value were observed. We note that the daily monitored values were in
some cases above the RfC and in some cases below. The daily values were
highly variable as they were likely influenced by wind direction and
speed. More information about the health benchmark value is available
in section III.B. More information on the School Air Toxics Initiative
can be found at http://www.epa.gov/schoolair/index/html, while the
study including the area around this facility can be found at http://www.epa.gov/schoolair/pdfs/MariettaTechReport.pdf. The monitoring was
conducted for the School Air Toxics Initiative; however we do present a
comparison of modeled concentrations to monitored concentrations in the
Risk Assessment document, which is available in the docket.
III. Analyses Performed
In this section, we describe the analyses performed to support the
proposed decisions for the RTR for this source category.
A. How did we address unregulated emissions sources?
In the course of evaluating the Ferroalloys Production source
category, we identified certain HAP for which we failed to establish
emission standards in the original MACT. See National Lime v. EPA, 233
F. 3d 625, 634 (DC Cir. 2000) (EPA has ``clear statutory obligation to
set emissions standards for each listed HAP''). Specifically, we
identified and evaluated emissions standards for four HAP (or groups of
HAP), described below, that are not specifically regulated in the
existing 1999 MACT standard, or are only regulated for certain
emissions points. As described below, for these HAP (or groups of HAP),
we are proposing emissions limits pursuant to section 112(d)(2) and
112(d)(3). The results and proposed decisions based on the analyses
performed pursuant to CAA section 112(d)(2) and 112(d)(3) are presented
in section IV.A of this preamble.
1. Hydrochloric acid
We were unaware of the potential for hydrochloric acid (HCl)
emissions when we developed the 1999 NESHAP. As a result, we did not
establish standards for HCl for these sources in the 1999 NESHAP. We
recently received HCl emissions data in response to the ICR. Therefore,
we are proposing a standard pursuant to section 112(d)(2) and (d)(3)
(as described further in section IV.A of this preamble).
2. Mercury
The 1999 NESHAP specified emissions limits for particulate metal
HAP (e.g., manganese, arsenic, nickel, chromium) in terms of a
particulate matter emissions limit (i.e., particulate matter is used as
a surrogate for metal HAP that are mainly emitted in particulate form).
There is no explicit standard for mercury, and a significant fraction
of the mercury emissions are expected to be in gaseous mercury forms
(e.g., gaseous elemental mercury or gaseous oxidized mercury) with a
smaller fraction in particulate form. Therefore, we are proposing a
standard specifically for mercury pursuant to section 112(d)(2) and
(d)(3) (as described further in section IV.A of this preamble).
[[Page 72516]]
3. Polycyclic Aromatic Hydrocarbons
As described above, the 1999 NESHAP only regulated particulate
metal HAP emissions and did not establish standards for PAH. Since
then, we have determined that electric arc furnaces emit PAH, and we
are proposing a standard pursuant to section 112(d)(2) and (d)(3) (as
described further in section IV.A of this preamble).
4. Formaldehyde
As described above, the 1999 NESHAP only regulated particulate
metal HAP emissions and did not establish standards for formaldehyde.
Since then, we have determined that electric arc furnaces emit
formaldehyde, and we are proposing a standard pursuant to section
112(d)(2) and (d)(3) (as described further in section IV.A of this
preamble).
B. 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 each source in the source category,
the HI for chronic exposures to HAP with the potential to cause
noncancer health effects, and the hazard quotient (HQ) for acute
exposures to HAP with the potential to cause noncancer health effects.
The assessment also provided estimates of the distribution of cancer
risks within the exposed populations, cancer incidence and an
evaluation of the potential for adverse environmental effects for each
source category. The risk assessment 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
Ferroalloys Production Source Category. The methods used to assess
risks (as described in the seven primary steps below) are consistent
with those peer-reviewed by a panel of the EPA's Science Advisory Board
(SAB) in 2009 and described in their peer review report issued in 2010;
\8\ they are also consistent with the key recommendations contained in
that report.
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\8\ U.S. EPA SAB. Risk and Technology Review (RTR) Risk
Assessment Methodologies: For Review by the EPA's Science Advisory
Board with Case Studies--MACT I Petroleum Refining Sources and
Portland Cement Manufacturing, May 2010.
---------------------------------------------------------------------------
1. Establishing the Nature and Magnitude of Actual Emissions and
Identifying the Emissions Release Characteristics
The two existing ferromanganese and silicomanganese production
facilities constitute the dataset that is the basis for the risk
assessment. We estimated the magnitude of emissions using data
collected through the ICR. In addition to the quality assurance (QA) of
the source data for the facilities contained in the dataset, we also
checked the coordinates of every emission source in the dataset through
visual observations using tools such as GoogleEarth and ArcView. Where
coordinates were found to be incorrect, we identified and corrected
them to the extent possible. We also performed QA of the emissions data
and release characteristics to ensure the data were reliable and that
there were no outliers.
2. Establishing the Relationship Between Actual Emissions and MACT-
Allowable Emissions Levels
The emissions data in the MACT dataset include estimates of the
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 facilities 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
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 because 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.)
For the Ferroalloys Production source category, we evaluated
allowable stack emissions, 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. Further explanation is provided in the
technical document: Draft Development of the RTR Emissions Dataset for
the Ferroalloys Production Source Category, which is available in the
docket.
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 air dispersion model used by the HEM-3 model (AERMOD) is one of
the EPA's preferred models for assessing pollutant concentrations from
industrial facilities.\9\ 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 189 meteorological stations,
selected to provide coverage of the United States and Puerto Rico. A
second library, of United States Census Bureau census block \10\
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 the EPA for HAP and other toxic air
pollutants. These values are available at http://www.epa.gov/ttn/atw/toxsource/summary.html and are
[[Page 72517]]
discussed in more detail later in this section.
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\9\ 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).
\10\ A census block is the smallest geographic area for which
census statistics are tabulated.
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In developing the risk assessment for chronic exposures, we used
the estimated annual average ambient air concentrations 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 each facility as the cancer risk associated with
a continuous lifetime (24 hours per day, 7 days per week, and 52 weeks
per year for a 70-year period) exposure to the maximum concentration at
the centroid of inhabited census blocks. 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
([mu]g/m\3\)) 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. For residual risk assessments, we generally use
URE values from the EPA's Integrated Risk Information System (IRIS).
For carcinogenic pollutants without the EPA IRIS values, we look to
other reputable sources of cancer dose-response values, often using
California EPA (CalEPA) URE values, where available. In cases where
new, scientifically credible dose response values have been developed
in a manner consistent with the EPA guidelines and have undergone a
peer review process similar to that used by the EPA, we may use such
dose-response values in place of, or in addition to, other values, if
appropriate. In the case of nickel compounds, to provide a health
protective estimate of potential cancer risks, we used the URE value
for nickel subsulfide in this assessment. Based on past scientific and
technical considerations, the determination of the percent of nickel
subsulfide was considered a major factor for estimating the extent and
magnitude of the risks of cancer due to nickel-containing emissions.
Nickel speciation information for some of the largest nickel-emitting
sources (including oil combustion, coal combustion, and others)
suggested that at least 35 percent of the total nickel emissions may be
soluble compounds and that the URE for the mixture of inhaled nickel
compounds (based on nickel subsulfide, and representative of pure
insoluble crystalline nickel) could be derived to reflect the
assumption that 65 percent of the total mass of nickel may be
carcinogenic. Based on consistent views of major scientific bodies
(i.e., National Toxicology Program in their 12th Report on
Carcinogens,\11\ International Agency for Research on Cancer,\12\ and
other international agencies) \13\ that consider all nickel compounds
to be carcinogenic, we currently consider all nickel compounds to have
the potential of being carcinogenic to humans. The major scientific
bodies mentioned above have also recognized that there are differences
in toxicity and/or carcinogenic potential across the different nickel
compounds. More discussion of the nickel URE can be found in the risk
assessment report in the docket for this action. For this analysis, to
take a more health-protective approach, we considered all nickel
compounds to be as carcinogenic as nickel subsulfide in our inhalation
risk assessments and have applied the IRIS URE for nickel subsulfide
without a factor to reflect the assumption that 100 percent of the
total mass of nickel may be as carcinogenic as pure nickel subsulfide.
In addition, given that there are two URE values \14\ derived for
exposure to mixtures of nickel compounds, as a group, that are 2-3 fold
lower than the IRIS URE for nickel subsulfide, we also consider it
reasonable to use a value that is 50 percent of the IRIS URE for nickel
subsulfide for providing an estimate of the lower end of a plausible
range of cancer potency values for different mixtures of nickel
compounds.
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\11\ National Toxicology Program (NTP), 2011. Report on
carcinogens. 12th ed. Research Triangle Park, NC: U.S. Department of
Health and Human Services (DHHS), Public Health Service. Available
online at http://ntp.niehs.nih.gov/ntp/roc/twelfth/roc12.pdf.
\12\ International Agency for Research on Cancer (IARD), 1990.
IARC monographs on the evaluation of carcinogenic risks to humans.
Chromium, nickel, and welding. Vol. 49. Lyons, France: International
Agency for Research on Cancer, World Health Organization Vol.
49:256.
\13\ World Health Organization (WHO, 1991) and the European
Union's Scientific Committee on Health and Environmental Risks
(SCHER, 2006).
\14\ Two UREs (other than the current IRIS values) have been
derived for nickel compounds as a group: one developed by the
California Department of Health Services (http://www.arb.ca.gov/toxics/id/summary/nickel_tech_b.pdf) and the other by the Texas
Commission on Environmental Quality (http://www.epa.gov/ttn/atw/nata1999/99pdfs/healtheffectsinfo.pdf).
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We also note that polycyclic organic matter (POM) (of which PAH are
a subset), a carcinogenic HAP with a mutagenic mode of action, is
emitted by the facilities in this source category.\15\ For this
compound group,\16\ the age-dependent adjustment factors (ADAF)
described in the EPA's Supplemental Guidance for Assessing
Susceptibility from Early-Life Exposure to Carcinogens \17\ were
applied. This adjustment has the effect of increasing the estimated
lifetime risks for POM by a factor of 1.6. In addition, although only a
small fraction of the total POM emissions were not reported as
individual compounds, the EPA expresses carcinogenic potency for
compounds in this group in terms of benzo[a]pyrene equivalence, based
on evidence that carcinogenic POM has the same mutagenic mechanism of
action as benzo[a]pyrene. For this reason, the EPA's Science Policy
Council \18\ recommends applying the Supplemental Guidance to all
carcinogenic PAH for which risk estimates are based on relative
potency. Accordingly, we have applied the ADAF to the benzo[a]pyrene
equivalent portion of all POM mixtures.
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\15\ U.S. EPA. Performing risk assessments that include
carcinogens described in the Supplemental Guidance as having a
mutagenic mode of action. Science Policy Council Cancer Guidelines
Implementation Work Group Communication I: Memo from W.H. Farland,
dated October 4, 2005.
\16\ See the Risk Assessment for Source Categories document
available in the docket for a list of HAP with a mutagenic mode of
action.
\17\ U.S. EPA Supplemental Guidance for Assessing Early-Life
Exposure to Carcinogens. EPA/630/R-3/003F, 2005. http://www.epa.gov/ttn/atw/childrens_supplement_final.pdf.
\18\ U.S. EPA Science Policy Council Cancer Guidelines
Implementation Workgroup Communication II: Memo from W.H. Farland,
dated June 14, 2006.
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Incremental individual lifetime cancer risks associated with
emissions from the two facilities 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 \19\)
emitted by the modeled source. Cancer incidence and the distribution of
individual cancer risks for the population within 50 km of the sources
were also estimated for the source category as part of this assessment
by summing individual risks. A distance of 50 km is consistent with
both the
[[Page 72518]]
analysis supporting the 1989 Benzene NESHAP (54 FR 38044) and the
limitations of Gaussian dispersion models, including AERMOD.
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\19\ 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 Science Advisory Board (SAB) in their
2002 peer review of EPA's National Air Toxics Assessment (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.
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To assess the 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
reference concentration (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 from
the EPA's IRIS database is not available, the EPA will utilize the
following prioritized sources for our chronic dose-response values: (1)
The Agency for Toxic Substances and Disease Registry Minimum Risk
Level, which is defined as ``an estimate of daily human exposure to a
substance that is likely to be without an appreciable risk of adverse
effects (other than cancer) over a specified duration of exposure'';
(2) the CalEPA Chronic Reference Exposure Level (REL), which is defined
as ``the concentration level at or below which no adverse health
effects are anticipated for a specified exposure duration''; and (3),
as noted above, in cases where scientifically credible dose-response
values have been developed in a manner consistent with the EPA
guidelines and have undergone a peer review process similar to that
used by the EPA, we may use those dose-response values in place of or
in concert with other values.
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 is located at this spot at a time when both the peak
(hourly) emission rate and worst-case dispersion conditions (1991
calendar year data) occur. The acute HQ is the estimated acute exposure
divided by the acute dose-response value. In each case, acute HQ values
were calculated using best available, short-term dose-response values.
These acute dose-response values, which are described below, include
the acute REL, acute exposure guideline levels (AEGL) and emergency
response planning guidelines (ERPG) for 1-hour exposure durations. 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.'' Acute REL values are
based on the most sensitive, relevant, adverse health effect reported
in the medical and toxicological literature. Acute REL values are
designed to protect the most sensitive individuals in the population by
the inclusion of margins of safety. Because margins of safety are
incorporated to address data gaps and uncertainties, exceeding the REL
does not automatically indicate an adverse health impact.
AEGL values were derived in response to recommendations from the
National Research Council (NRC). As described in Standing Operating
Procedures (SOP) of the National Advisory Committee on Acute Exposure
Guideline Levels for Hazardous Substances (http://www.epa.gov/opptintr/aegl/pubs/sop.pdf),\20\ ``the NRC's previous name for acute exposure
levels--community emergency exposure levels--was replaced by the term
AEGL to reflect the broad application of these values to planning,
response, and prevention in the community, the workplace,
transportation, the military, and the remediation of Superfund sites.''
This document also states that AEGL values ``represent threshold
exposure limits for the general public and are applicable to emergency
exposures ranging from 10 minutes to eight hours.'' The document lays
out the purpose and objectives of AEGL by stating (page 21) that ``the
primary purpose of the AEGL program and the National Advisory Committee
for Acute Exposure Guideline Levels for Hazardous Substances is to
develop guideline levels for once-in-a-lifetime, short-term exposures
to airborne concentrations of acutely toxic, high-priority chemicals.''
In detailing the intended application of AEGL values, the document
states (page 31) that ``[i]t is anticipated that the AEGL values will
be used for regulatory and nonregulatory purposes by U.S. Federal and
state agencies and possibly the international community in conjunction
with chemical emergency response, planning, and prevention programs.
More specifically, the AEGL values will be used for conducting various
risk assessments to aid in the development of emergency preparedness
and prevention plans, as well as real-time emergency response actions,
for accidental chemical releases at fixed facilities and from transport
carriers.''
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\20\ NAS, 2001. Standing Operating Procedures for Developing
Acute Exposure Levels for Hazardous Chemicals, page 2.
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The AEGL-1 value is then specifically defined as ``the airborne
concentration of a substance above which it is predicted that the
general population, including susceptible individuals, could experience
notable discomfort, irritation, or certain asymptomatic nonsensory
effects. However, the effects are not disabling and are transient and
reversible upon cessation of exposure.'' The document also notes (page
3) that, ``Airborne concentrations below AEGL-1 represent exposure
levels that can produce mild and progressively increasing but transient
and nondisabling odor, taste, and sensory irritation or certain
asymptomatic, nonsensory effects.'' Similarly, the document defines
AEGL-2 values as ``the airborne concentration (expressed as parts per
million or milligrams per cubic meter of a substance above which it is
predicted that the general population, including susceptible
individuals, could experience irreversible or other serious, long-
lasting adverse health effects or an impaired ability to escape.''
ERPG values are derived for use in emergency response, as described
in the American Industrial Hygiene Association's document entitled,
Emergency Response Planning Guidelines (ERPG) Procedures and
Responsibilities (http://www.aiha.org/1documents/committees/ERPSOPs2006.pdf) which states that, ``Emergency Response Planning
Guidelines were developed for emergency planning and are intended as
health based guideline concentrations for single exposures to
chemicals.'' \21\ The ERPG-1 value is defined as ``the maximum airborne
concentration below which it is believed that nearly all individuals
could be exposed for up to 1 hour without experiencing other than mild
transient adverse health effects or without perceiving a clearly
defined, objectionable odor.'' Similarly, the ERPG-2 value is defined
as ``the maximum airborne concentration below which it is believed that
nearly all individuals could be exposed for up to 1 hour without
experiencing or
[[Page 72519]]
developing irreversible or other serious health effects or symptoms
which could impair an individual's ability to take protective action.''
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\21\ ERP Committee Procedures and Responsibilities. November 1,
2006. American Industrial Hygiene Association.
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As can be seen from the definitions above, the AEGL and ERPG values
include the similarly-defined severity levels 1 and 2. For many
chemicals, a severity level 1 value AEGL or ERPG has not been developed
because the types of effects for these chemicals are not consistent
with the AEGL-1/ERPG-1 definitions; in these instances, higher severity
level AEGL-2 or ERPG-2 values are compared to our modeled exposure
levels to screen for potential acute concerns. When AEGL-1/ERPG-1
values are available, they are used in our acute risk assessments.
Acute REL values for 1-hour exposure durations are typically lower
than their corresponding AEGL-1 and ERPG-1 values. Even though their
definitions are slightly different, AEGL-1 values are often the same as
the corresponding ERPG-1 values, and AEGL-2 values are often equal to
ERPG-2 values. Maximum HQ values from our acute screening risk
assessments typically result when basing them on the acute REL value
for a particular pollutant. In cases where our maximum acute HQ value
exceeds 1, we also report the HQ value based on the next highest acute
dose-response value (usually the AEGL-1 and/or the ERPG-1 value).
To develop screening estimates of acute exposures in the absence of
hourly emissions data, generally we first develop estimates of maximum
hourly emissions rates by multiplying the average actual annual hourly
emissions rates by a default factor to cover routinely variable
emissions. For the Ferroalloys Production source category hourly
emissions estimates were available for individual emissions points, so
we did not use the default factor of 10. Using emission test data,
hourly emission rates were developed for those processes considered to
operate continuously (i.e., steady-state operations for 8,760 hours per
year) and for those processes considered to operate intermittently
(i.e., non-steady-state operations for less than 8,760 hours per year).
A discussion of the hourly emissions estimates is provided in the
Methodology for Estimation of Maximum Hourly Emissions for Ferroalloy
Sources, which is available in the docket for this action.
As part of our acute risk assessment process, for cases where 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 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. For this source
category, the data refinements employed consisted of using the site-
specific facility layout to distinguish facility property from an area
where the public could be exposed. These refinements are discussed in
the draft risk assessment document, which is available in the docket
for this source category. 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 approach.
To better characterize the potential health risks associated with
estimated acute exposures to HAP, and in response to a key
recommendation from the SAB's peer review of the EPA's RTR risk
assessment methodologies,\22\ we generally examine a wider range of
available acute health metrics (e.g., RELs, AEGLs) than we do for our
chronic risk assessments. This is in response to the SAB's
acknowledgement that there are generally more data gaps and
inconsistencies in acute reference values than there are in chronic
reference values. In some cases, when Reference Value Arrays \23\ for
HAP have been developed, we consider additional acute values (i.e.,
occupational and international values) to provide a more complete risk
characterization.
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\22\ The SAB peer review of RTR Assessment Methodologies is
available at: http://yosemite.epa.gov/sab/sabproduct.nsf/
4AB3966E263D943A8525771F00668381/$File/EPA-SAB-10-007-unsigned.pdf
\23\ U.S. EPA. (2009) Chapter 2.9 Chemical Specific Reference
Values for Formaldehyde in Graphical Arrays of Chemical-Specific
Health Effect Referenhce Values for Inhalation Exposures (Final
Report). U.S. Environmental Protection Agency, Washington, DC, EPA/
600/r-09/061, and available on-line at http://cfpub.epa.gov/ncea/dfm/recordisplay.cfm?deid=211003.
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4. Conducting Multipathway Exposure and Risk Screening
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 two-
step process. In the first step, we determined whether any facilities
emitted any PB-HAP (HAP known to be persistent and bio-accumulative in
the environment). There are 14 PB-HAP compounds or compound classes
identified for this screening in the 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, hexachlorocyclohexane, lead compounds,
mercury compounds, methoxychlor, polychlorinated biphenyls, POM,
toxaphene and trifluralin.
Because one or more of these PB-HAP are emitted by at least one
facility in the source category, we proceeded to the second step of the
evaluation. In this step, we determined whether the facility-specific
emission rates of each of the emitted PB-HAP were large enough to
create the potential for significant non-inhalation human or
environmental risks under reasonable worst-case conditions. To
facilitate this step, we have developed emission rate thresholds for
each PB-HAP using a hypothetical worst-case screening exposure scenario
developed for use in conjunction with the EPA's Total Risk Integrated
Methodology.Fate, Transport, and Ecological Exposure (TRIM.FaTE) model.
The hypothetical screening scenario was subjected to a sensitivity
analysis to ensure that its key design parameters were established such
that environmental media concentrations were not underestimated (i.e.,
to minimize the occurrence of false negatives or results that suggest
that risks might be acceptable when, in fact, actual risks are high)
and to also minimize the occurrence of false positives for human health
endpoints. We call this application of the TRIM.FaTE model TRIM-Screen.
The facility-specific emission rates of each of the PB-HAP in the
source category were compared to the TRIM-Screen emission threshold
values for each of the PB-HAP identified in the source category
datasets to assess the potential for significant human health risks or
environmental risks via non-inhalation pathways.
5. Assessing Risks Considering Emissions Control Options
In addition to assessing baseline inhalation risks and screening
for potential multipathway risks, we also estimated risks considering
the potential emissions reductions that would be achieved by the main
control options
[[Page 72520]]
under consideration. In these cases, 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: Facilitywide Assessments
To put the source category risks in context, we typically 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
emissions sources at the facility for which we have data. However, for
the Ferroalloys Production source category, there are no other
significant HAP emissions sources operating at present. Thus, there was
no need to perform a separate facility wide risk assessment.
7. Considering Uncertainties in Risk Assessment
Uncertainty and the potential for bias are inherent in all risk
assessments, including those performed for the source category
addressed in this proposal. Although uncertainty exists, we believe
that our approach, 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
the Ferroalloys Production Source Category) 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, errors were made in estimating
emissions values and other factors. The emission estimates considered
in this analysis generally are annual totals for certain years that do
not reflect short-term fluctuations during the course of a year or
variations from year to year.
The estimates of peak hourly emissions rates from stacks for the
acute effects screening assessment were based on actual maximum hourly
emissions estimates for individual emission points, which is intended
to account for emissions fluctuations due to normal facility
operations.
b. Uncertainties in Dispersion Modeling
While the analysis employed the 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, model options (e.g., rural/urban, plume
depletion, chemistry) were selected to provide an overestimate of
ambient air concentrations of the HAP rather than underestimates.
However, because of practicality and data limitation reasons, some
factors (e.g., meteorology, building downwash) have the potential in
some situations to overestimate or underestimate ambient impacts. For
example, meteorological data were taken from a single year (1991) and
facility locations can be a significant distance from the site where
these data were taken. 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.
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.\24\
The assumption of not considering short or long-term population
mobility does not bias the estimate of the theoretical MIR, nor does it
affect the estimate of cancer incidence because the total population
number remains the same. It does, however, affect the shape of the
distribution of individual risks across the affected population,
shifting it toward higher estimated individual risks at the upper end
and reducing the number of people estimated to be at lower risks,
thereby increasing the estimated number of people at specific high risk
levels (e.g., one in 10,000 or one in one million).
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\24\ Short-term mobility is movement from one micro-environment
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.
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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, but is an unbiased estimate
of average risk and incidence.
The assessment evaluates the 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 emissions 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.
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.\25\
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\25\ U.S. EPA. National-Scale Air Toxics Assessment for 1996.
(EPA 453/R-01-003; January 2001; page 85.)
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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
[[Page 72521]]
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 be worst-case actual exposures as 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 the 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 variability 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).\26\ In some circumstances, the true risk could be as
low as zero; however, in other circumstances the risk could be
greater.\27\ 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, the 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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\26\ IRIS glossary (http://www.epa.gov/NCEA/iris/help_gloss.htm).
\27\ 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.
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Chronic non-cancer reference (RfC) and reference dose (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 considers uncertainty, variability and gaps in the
available data. The UF are applied to derive reference values that are
intended to protect against appreciable risk of deleterious effects.
The UF are commonly default values,\28\ e.g., factors 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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\28\ 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. The 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).
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 noncancer effects for all pollutants emitted by
the sources included in this assessment, some HAP continue to have no
reference values for cancer or chronic noncancer or acute
[[Page 72522]]
effects. Because 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. For a group of
compounds that are either unspeciated or do not have reference values
for every individual compound (e.g., glycol ethers), we conservatively
use the most protective reference value to estimate risk from
individual compounds in the group of compounds.
Additionally, chronic reference values for several of the compounds
included in this assessment are currently under the EPA IRIS review 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 these reviews are completed prior to our
taking final action for this source category and 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 multipathway and
environmental effects is necessary. Our screening methods use worst-
case scenarios to determine whether multipathway impacts might be
important. The results of such a process are biased high for the
purpose of screening out potential impacts. Thus, when individual
pollutants or facilities screen out, we are confident that the
potential for multipathway impacts is negligible. On the other hand,
when individual pollutants or facilities do not screen out, it does not
mean that multipollutant impacts are significant, only that we cannot
rule out that possibility.
C. How did we consider the risk results in making decisions for this
proposal?
In evaluating and developing standards under section 112(f)(2), as
discussed in section I.B of this preamble, we apply a two-step process
to address residual risk. In the first step, the EPA determines whether
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)
\29\ of approximately one in 10 thousand [i.e., 100 in one million]''
(54 FR 38045). In the second step of the process, the 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 one in one million, as
well as other relevant factors, including costs and economic impacts,
technological feasibility, and other factors relevant to each
particular decision.'' (Id.)
---------------------------------------------------------------------------
\29\ 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.
---------------------------------------------------------------------------
In past residual risk actions, the 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 HI;
and the maximum acute non-cancer hazard (72 FR 25138, May 3, 2007; 71
FR 42724, July 27, 2006). In most recent proposals (75 FR 65068,
October 21, 2010; 75 FR 80220, December 21, 2010; and 76 FR 29032, May
19, 2011), the EPA also presented and considered additional measures of
health information, such as 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). The EPA also discussed and considered risk
estimation uncertainties. The EPA is providing this same type of
information in support of the proposed actions described in this
Federal Register notice.
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 [previous] section 112 is best
judged on the basis of a broad set of health risk measures and
information'' (54 FR 38046). Similarly, with regard to making the ample
margin of safety determination, as stated in the Benzene NESHAP ``[in
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 the Benzene NESHAP provides
flexibility regarding what factors the EPA might consider in making
determinations and how these factors might be weighed for each source
category. In responding to comment on our policy under the Benzene
NESHAP, the 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).
Thus, the level of the MIR is only one factor to be weighed in
determining acceptability of risks. The Benzene NESHAP explained that
``an MIR of approximately one 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, the 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).
[[Page 72523]]
The 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 generally we have also assessed risks due to HAP
emissions from the entire facility at which the covered source category
is located (facilitywide risk estimates). We have not, however,
attempted 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 emissions from other facilities that do not
include the source categories in question, 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 health reference levels (e.g., RfCs) 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 EPA 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.'' \30\
---------------------------------------------------------------------------
\30\ 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.
---------------------------------------------------------------------------
Although we are interested in placing source category and
facilitywide 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 facilitywide estimates,
and hence would compound 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 the
EPA's 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).
D. How did we perform the technology review?
Our technology review focused on the identification and evaluation
of developments in practices, processes, and control technologies that
have occurred since the 1999 NESHAP was promulgated. In cases where the
technology review identified such developments, we conducted an
analysis of the technical feasibility of applying these developments,
along with the estimated impacts (costs, emissions reductions, risk
reductions, etc.) of applying these developments. We then made
decisions on whether it is necessary to propose amendments to the 1999
NESHAP to require any of the identified developments.
Based on our analyses of the data and information collected by the
ICR and our general understanding of the industry and other available
information on potential controls for this industry, we identified
several potential 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 development of the 1999 NESHAP.
Any improvements in add-on control technology or other
equipment (that were identified and considered during development of
the 1999 NESHAP) that could result in significant additional emissions
reduction.
Any work practice or operational procedure that was not
identified or considered during development of the 1999 NESHAP.
Any process change or pollution prevention alternative
that could be broadly applied to the industry and that was not
identified or considered during development of the 1999 NESHAP.
In addition to reviewing the practices, processes, or control
technologies that were not considered at the time we developed the 1999
NESHAP, we reviewed a variety of data sources in our evaluation of
whether there were additional practices, processes, or controls to
consider for the Ferroalloys Production industry. Among the data
sources we reviewed were the NESHAP for various industries that were
promulgated after the 1999 NESHAP. We reviewed the regulatory
requirements and/or technical analyses associated with these regulatory
actions to identify any practices, processes, and control technologies
considered in these efforts that could possibly be applied to emissions
sources in the Ferroalloys Production source category, as well as the
costs, non-air impacts, and energy implications associated with the use
of these technologies.
Additionally, we requested information from facilities regarding
developments in practices, processes, or control technology. Finally,
we reviewed other information sources, such as State or local
permitting agency databases and industry-supported databases.
E. What other issues are we addressing in this proposal?
In addition to the analyses described above, we also reviewed other
aspects of the MACT standards for possible revision as appropriate and
necessary. Based on this review we have identified aspects of the MACT
standards that we believe need revision. This includes proposing
revisions to the startup, shutdown, and malfunction (SSM) provisions of
the MACT rule in order to ensure that they are consistent with a recent
court decision in Sierra Club v. EPA, 551 F. 3d 1019 (DC Cir. 2008). In
addition, we are proposing various other changes to monitoring and
testing requirements to ensure that this rule includes the measures
needed to ensure continuous compliance at major sources subject to the
revised NESHAP for the Ferroalloys Production source category.
[[Page 72524]]
Our analyses and proposed decisions related to SSM and other testing
and reporting requirements for this source category are presented in
section IV.E of this preamble.
IV. Analytical Results and Proposed Decisions
This section of the preamble provides the results of our review of
the MACT rule including the RTR for the Ferroalloys Production source
category and our proposed decisions concerning changes to the 1999
NESHAP.
A. What are the results of our analyses and proposed decisions
regarding unregulated pollutants?
In this section, we describe how we addressed unregulated
emissions, including how we calculate MACT floors, how we account for
variability in those floor calculations, and how we consider beyond the
floor options. As described previously, the CAA section 112(d) requires
the EPA to promulgate national technology-based emission standards for
hazardous air pollutants (NESHAP) for listed source categories,
including this source category. For more information on this analysis,
see the Draft MACT Floor Analysis for the Ferroalloys Production Source
Category which is available in the docket for this proposed action.
Based on the ICR data that we collected, we conducted a MACT Floor
analysis.
Section 112(d)(3)(B) of the CAA requires that the MACT standards
for existing sources be at least as stringent as the average emissions
limitation achieved by the best performing five sources (for which the
Administrator has or could reasonably obtain emissions information) in
a category with fewer than 30 sources. The Ferroalloy Production source
category consists of fewer than 30 sources. Where, as here, there are
five or fewer sources, we base the MACT floor limit on the average
emissions limitation achieved by those sources for which we have data.
The 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
under variable conditions. It is recognized in the case law that the
EPA may consider variability in estimating the degree of emissions
reduction achieved by best-performing sources and in setting MACT
floors. See Mossville Envt'l Action Now v. EPA, 370 F.3d 1232, 1241-42
(DC Cir 2004) (holding the EPA may consider emissions variability in
estimating performance achieved by best-performing sources and may set
the floor at a level that a best-performing source can expect to meet
``every day and under all operating conditions'').
With regard to data used to determine the MACT limits, we received
detailed emissions data for multiple HAP from one furnace and one
crushing system baghouse at each plant (collected at the outlet of the
control device) based on an ICR sent to the two companies in 2010. We
are soliciting additional emissions data for the operating furnaces and
crushing system baghouses for which we do not have data and any other
emissions sources at ferroalloys production facilities including
available information on the quantity and composition of process
fugitive emissions.
1. Mercury Emissions
The raw materials used to produce ferroalloys contain various
amounts of mercury, which is emitted during the smelting process. These
mercury emissions are derived primarily from the manganese ore although
there may be trace amounts in the coke or coal used in the smelting
process. While some of the mercury that is in particulate or oxidized
forms is captured by the particulate control devices, the more volatile
elemental mercury is largely emitted to the atmosphere. We found that
mercury emissions are emitted from the furnaces as measured during the
ICR test program (estimated to be 540 pounds per year (lb/yr) at one
plant and 140 lb/yr at the other plant). Pursuant to CAA section
112(d)(2) and 112(d)(3), we are proposing to revise the 1999 NESHAP to
include emission limits for mercury.
As discussed above, the MACT floor limit is calculated based on the
average performance of the units in each category plus an amount to
account for these units' variability. To account for variability in the
operation and emissions, the stack test data were used to calculate the
average emissions and the 99 percent upper predictive limit (UPL) to
derive the MACT floor limit. For more information on how we calculated
the MACT floors and other emission limits, see the Ferroalloys
Production MACT Floor Analysis document, which is available in the
docket.
Using this method, the MACT floor (or 99 percent UPL) for exhaust
mercury concentrations from existing furnaces is 80 [micro]g/dscm at 2
percent carbon dioxide (CO2). This MACT floor limit is
higher than the actual emissions measured during the ICR performance
tests at each plant. Therefore, we anticipate that both of the existing
sources would be able to meet this limit without installing additional
controls.
With regard to new sources, as described above, the MACT floor for
new sources cannot be less stringent than the emissions performance
that is achieved in practice by the best-controlled similar source. A
variability analysis similar to that used for existing sources was then
performed to calculate a 99 percent UPL using the three run test data
from the top source. For this source category, we calculate that the
UPL MACT floor limit for new sources is 16 [micro]g/dscm at 2 percent
CO2. This limit is based on the performance of the best
performing source.
The next step in establishing MACT standards is the beyond the
floor analysis. In this step, we investigate other mechanisms for
further reducing HAP emissions that are more stringent than the MACT
floor level of control in order to ``require the maximum degree of
reduction in emissions'' of HAP. In setting such standards, section
112(d)(2) requires the Agency to consider the cost of achieving the
additional emission reductions, any non-air quality health and
environmental impacts, and energy requirements. Historically, these
factors have included factors such as solid waste impacts of a control,
effects of emissions on bodies of water, as well as the energy impacts.
As described below, we considered beyond-the-floor control options
to further reduce emissions of mercury. Because of our limited data
set, we considered setting a MACT limit for existing sources based on
the performance of the best performing source (i.e., based upon the
test data used to calculate the MACT floor for new sources) such that
the MACT limit for existing sources would be the same as the UPL MACT
limit for new sources (i.e., 16 [micro]g/dscm). Under this option, the
best performing source would need no additional controls to meet the
limit, since their current performance defines the new source limit.
With regard to the other facility in the source category, as described
below, we believe this limit could be achieved by the addition of an
activated carbon injection system, which is a proven technology for
mercury control. Compliance would be demonstrated by periodic
performance testing and continuous parameter monitoring.
In evaluating a beyond the floor option, we evaluate, among other
things, the costs of achieving additional emission reductions beyond
the floor level of control. No facilities in the source category use
add-on control devices or work practices to limit mercury emissions
beyond what is
[[Page 72525]]
achieved as co-control of the emissions with the particulate matter
control device. However, we identified both carbon bed technology and
activated carbon injection as commercially available mercury emission
reduction techniques. Carbon bed technology (which is one of the
primary control devices used at Industrial Gold Production facilities
in the U.S. to minimize mercury emissions, as described in the proposed
rule for that category \31\) does not appear to be a viable technology
to control the large volumes of airflow generated by the electric arc
furnaces in the Ferroalloys Production source category. The carbon bed
technology is applicable to gas streams with low volumes of airflow,
and is characterized with relatively high pressure drops. Accordingly
this technology is not used in industries with high volumes of airflow,
such as industrial boilers and power plants.
---------------------------------------------------------------------------
\31\ National Emission Standards for Hazardous Air Pollutants:
Gold Mine Ore Processing and Production Area Source Category.
Proposed Rule (75 FR 22470);
---------------------------------------------------------------------------
In contrast, activated carbon injection has been used to control
mercury emissions at various types of facilities that have large
volumes of airflow including some coal-fired power plants, waste
incinerators and cement kilns. Based on available information,
activated carbon injection appears to be a technologically feasible
control for mercury for these larger volume combustion sources. Mercury
reductions of up to 90 or 95 percent have been reported at these other
sources and should also be achievable at ferroalloys production
facilities. Based on data and information on these mercury controls for
other combustion sources (such as utility boilers, incinerators and
cement kilns), and based on our experience with these controls, we
conclude that activated carbon injection is a viable control technology
for the Ferroalloys Production source category.
Activated carbon injection can be installed upstream or downstream
of an existing particulate matter control device. In cases where a
source is concerned about potential impacts of waste carbon on the
source's waste stream and resulting disposal options or the ability to
sell or reuse baghouse dust, the source can install the activated
carbon injection downstream of the particulate matter control device
with a separate polishing baghouse to collect the carbon. In other
cases, the source can install the activated carbon injection upstream
of the particulate matter control device and use the existing
particulate control device to remove the carbon from the airstream.
We reviewed facility specific control options that included putting
the mercury controls downstream of the existing furnace baghouse to
avoid the potential issues with sale or reuse of baghouse dust
associated with upstream controls. Under this scenario, the activated
carbon injection system would be followed by a ``polishing'' baghouse
to capture the activated carbon for disposal. In the case of the
existing furnace scrubber, we assumed the source could put the
activated carbon injection system upstream of the scrubber, the carbon
would be captured by the scrubber and the resulting sludge treated
according to the existing treatment process at the plant. Based on
discussion \32\ with a vendor and other control technology experts, we
do not believe that the resulting carbon waste in either scenario would
trigger waste disposal concerns. We request comment on these
assumptions.
---------------------------------------------------------------------------
\32\ Conversation with D. Lipscomb, Albemarle. August 22, 2011.
---------------------------------------------------------------------------
We estimate that under this beyond the floor option described above
(i.e., a proposed limit of 16 [micro]g/dscm), that one facility would
need to install additional controls such as activated carbon injection
to meet this limit, and that this would achieve about 420 pounds of
reduction per year in mercury emissions. The capital costs are
estimated to be $1.7 million, annualized capital and operating costs to
be $1.4 million, with an overall cost-effectiveness of $3,300 per
pound. The general range of costs for mercury controls from other MACT
rules has been about $1,250 to $55,200 per pound of mercury removed (76
FR 25075, May 3, 2011). The EPA requests information on other control
technologies available to Ferroalloys Production manufacturers to
reduce mercury emissions. Other controls might include process changes,
substitution of materials, collection or enclosure systems, work
practices, or combinations of such methods; which reduce the volume of
mercury emissions from existing sources.
It is important to note that there is no bright line for
determining cost-effectiveness. Each rulemaking is different and
various factors must be considered. Nevertheless, the cost-
effectiveness of mercury controls in this proposed rule for Ferroalloys
Production is near the lower end of the range. Some of the factors we
consider in determining the costs of control technologies under section
112(d)(2) include, but are not limited to the following: total capital
costs; annual costs; and costs compared to total revenues (e.g., costs
to revenue ratios). Other factors besides cost are considered into our
decision. For example, whether the standards significantly impact one
or more small businesses, whether the controls would significantly
impact production, and whether, and to what extent, the controls result
in adverse impacts to other media (e.g., hazardous waste issues). We
propose that these mercury controls are feasible for the Ferroalloys
Production source category from a technical standpoint and are cost
effective. We are proposing a MACT standard for mercury emissions of 16
[micro]g/dscm for both existing and new sources under the authority of
sections 112(d)(2) and (d)(3). To meet this proposed limit, we have
preliminarily determined that activated carbon injection is feasible to
implement for the Ferroalloys Production source category from a
technical standpoint and that control costs fall within the range of
other mercury controls in other MACT rules. More information regarding
how the MACT standards were calculated and the costs is provided in
Ferroalloys Production MACT Floor and Cost Memos, which are available
in the docket for this rulemaking.
We are requesting comment on the proposed standard of 16 [micro]g/
dscm for mercury. We also seek comments and information on our
conclusion that activated carbon injection technology to meet the
mercury emissions limit for this source category is technically and
economically feasible. Moreover, we seek comments on the factors
related to costs and economics (such as those described in the
paragraph above) regarding the feasibility and costs of activated
carbon injection for this industry. We also seek comments on other
possible controls that could be effective to reduce mercury emissions
beyond the floor, including the amount and cost of the resulting
emissions reductions. Furthermore, we seek comment on whether work
practices to minimize mercury emissions, such as switching to manganese
ores with low mercury content, could be technically and economically
feasible.
Moreover, we request comment on whether there is a basis to
subcategorize manganese production operations for mercury. For example,
is there a basis on which to subcategorize ferromanganese production
and silicomanganese production processes? Although we are requesting
comment on subcategorization, we do not believe that subcategorization
would have any substantive effect on the resulting standards or the
costs of controls since
[[Page 72526]]
there would be no change in the costs and feasibility of mercury
controls evaluated for these sources.
We are proposing that any source installing activated carbon
injection would be required to continuously monitor the carbon
injection rate into the airstream being controlled. We request comment
on the level of variability in the carbon injection rate that should be
allowed, and what percent decrease in the rate should be considered
significant.
We also propose that sources monitor the mercury content in the
manganese ore. Specifically, we propose that the determination of a
significant increase in mercury content would be that the 12-month
rolling weighted average mercury concentration based on monthly
sampling in the manganese ore increases by 10 percent or more compared
to the baseline weighted average mercury concentration. If that limit
is exceeded, the source would be required to readjust the carbon
injection rate as specified in the source's monitoring plan or retest
within 30 days if there is not a dedicated mercury control device. If a
new ore is added, sampling would be required as well.
We request comment on this ore monitoring provision. We are
especially interested in any data that would show the variability in
mercury concentration between different ore samples from the same
location and the variability of the types of ores used in manganese
production. If ore type and mercury content are demonstrated to be
stable, we might consider reducing the frequency of sampling/
calculations to quarterly or less.
2. Polycyclic Aromatic Hydrocarbons (PAHs)
PAH emissions are products of incomplete combustion from the
smelting operation, and a subset of the listed HAP POM. Some of these
emissions are likely to be in particulate form, but a significant
portion is expected to be in a gaseous form. Therefore, the existing
particulate matter control devices only achieve partial control of
these compounds. No existing facilities in the source category control
PAH or use work practices to limit emissions of PAH emissions
specifically. However, under today's proposal, these pollutants would
be controlled with the same activated carbon injection technology as
mercury. Because of this, emission reductions could be achieved via co-
control at no additional costs. Pursuant to CAA section 112(d)(2) and
112(d)(3), we are proposing to revise the 1999 NESHAP to include an
emission limit for PAH.
We have stack test data from only one furnace for PAH emissions. As
such, the MACT floor would be based on the performance level achieved
at that furnace (i.e., the average emissions of that furnace plus an
amount to account for variability). Based on these data and applying
the 99 percent UPL, we calculate that the MACT floor limit for PAHs
would be 887 [micro]g/dscm. We also evaluated control performance that
could be achieved via co-control of mercury emissions with activated
carbon injection as a beyond-the-floor option. Based on information
from carbon vendors, an activated carbon system that is designed to
achieve a 90 percent reduction in mercury emissions (which we expect
would be applied to meet the proposed mercury standard discussed above)
should also achieve a high degree of reduction in PAH with no
additional costs. Assuming a 90 percent reduction from the calculated
99 percent UPL of 887 [micro]g/dscm, the resulting limit would be 89
[micro]g/dscm. Thus, a proposed limit for PAHs of 89 [micro]g/dscm
could be achieved with the same controls needed for mercury with no
additional costs.
Therefore, pursuant to CAA sections 112(d)(2) and (d)(3), we are
proposing to revise the 1999 NESHAP to include an emission limit for
PAH of 89 [micro]g/dscm for new and existing sources.
3. Hydrochloric acid
Hydrochloric acid (HCl) is a product of combustion, and the level
of emissions is dictated by the chlorine content of the coal or coke
used as a reducing agent in the smelting process. Based on test data
from the ICR, we estimate that the two facilities in this source
category emit 6 to 11 tpy of HCl. While these levels of emissions are
nontrivial, they are relatively low compared to some other types of
combustion sources. The primary reason for this is that manganese
producers use coke instead of coal as the primary reducing agent in the
smelting operation. Because coke is a refined product, much of the
original chlorine content in the coal is removed in the coking process,
which greatly reduces potential emissions. Second, one of the five
furnaces at these plants is equipped with a scrubber, which provides
co-control of particulate matter and HCl emissions. Notwithstanding the
relatively low HCl emissions from facilities in this source category,
section 112(d) requires us to set MACT for HAP emitted from the source
category. Pursuant to CAA section 112(d)(2) and 112(d)(3), we are
proposing to revise the 1999 NESHAP to include emission limits for HCl.
As discussed above, the MACT floor limit is calculated based on the
average performance of the units in each category plus an amount to
account for these units' variability. To account for variability in the
operation and emissions, the stack test data were used to calculate the
average emissions and the 99 percent UPL to derive the MACT floor
limit. However, a number (50 percent) of the individual data points
were reported as below the applicable test detection limits.\33\ The
following discussion describes how we handle such data in our MACT
calculations. Also, as described below, we request comment on how this
uncertainty might influence establishing an emission limit instead of a
work practice standard.
---------------------------------------------------------------------------
\33\ We conducted this analysis for all measured pollutant
according to the following method when non detects were reported.
However only the hydrochloric acid and formaldehyde data needed a
detection limit correction to adequately account for variability, as
described below.
---------------------------------------------------------------------------
Test method measurement imprecision is a contributor to the
variability of a set of emissions data. One element is associated with
method detection capabilities and a second is a function of the
measurement value. Measurement imprecision is proportionally highest
for values measured below or near a method's detection level and
proportionally lower for values measured above the method detection
level.
The probability procedures applied in calculating the MACT floor or
beyond the floor emissions limit inherently and reasonably account for
emissions data variability including measurement imprecision when the
database represents multiple tests from multiple emissions units for
which all of the data are measured significantly above the method
detection level. This is less true when the database includes some
emissions occurring below method detection capabilities that are
reported as the method detection level values.
The EPA's guidance to facilities for reporting pollutant emissions
in response to the ICR data collection specified the criteria for
determining test-specific method detection levels. Those criteria
ensure that there is only about a 1 percent probability of an error in
deciding that the pollutant measured at the method detection level is
present when in fact it was absent. Such a probability is also called a
false positive or an alpha, Type I, error. Because of sample and
emissions matrix effects, laboratory techniques, sample size, and other
factors, method detection levels normally vary from test to test for
any specific test method and pollutant measurement. The expected
[[Page 72527]]
measurement imprecision is 40 to 50 percent or greater at levels
measured at the method detection level or less. The expected
measurement imprecision decreases to 10 to 15 percent for values
measured at a level about three times the method detection level or
greater.\34\
---------------------------------------------------------------------------
\34\ American Society of Mechanical Engineers, Reference Method
Accuracy and Precision (ReMAP): Phase 1, Precision of Manual Stack
Emission Measurements, CRTD Vol. 60, February 2001.
---------------------------------------------------------------------------
Also in accordance with our guidance, source owners identified
emissions data which were measured below the method detection level and
reported those values as equal to the method detection level as
determined for that test. An effect of reporting data in this manner is
that the resulting database is somewhat truncated at the lower end of
the measurement range (i.e., no values reported below the test-specific
method detection level). A MACT floor or beyond the floor emissions
limit based on a truncated database or otherwise including values
measured near the method detection level may not adequately account for
measurement imprecision contribution to the data variability.
We applied the following procedures to account for the effect of
measurement imprecision associated with a database that includes method
detection level data. The following process also addresses the concerns
associated with use of a small data set, such as the Ferroalloys
Production data set for HCl. As a first step, we reviewed an HCl
emissions data set for the industrial boilers rule, which represents
several hundred emissions tests used in the floor calculations (i.e.,
best performers) for the boilers rule to determine typical method
detection levels. We have data from multiple industrial boilers tests
and used those data to confirm that method detection levels that
testers reported were as good as or better (i.e., lower) than the
values reported in the method. We presume that data for the best
performing units also reflect the capabilities of high quality testing
companies and laboratories. Further, the method detection levels
calculated from larger data sets are more representative of the
inherent measurement variability both within and between testing
companies than the limited Ferroalloys Production dataset. We believe
that emissions tests conducted with these methods for most combustion
operations (e.g., fossil fuel, biomass, and waste fired units; brick
and clay kilns; Portland cement kilns), including ferroalloys
production, should produce method detection levels very similar to the
level of 60 [micro]g/dscm that is the result of this review.
The second step in the process was to calculate three times the RDL
and compare that value to the calculated MACT floor or beyond the floor
emissions limit. We use the multiplication factor of three to
approximate a 99 percent upper confidence interval for a data set of
seven or more values. If three times the RDL was less than the
calculated MACT floor emissions limit calculated from the UPL, we would
conclude that measurement variability was adequately addressed. The
calculated MACT floor or beyond the floor emissions limit would need no
adjustment. If, on the other hand, the value equal to three times the
RDL was greater than the UPL, we would conclude that the calculated
MACT floor or beyond the floor emissions limit does not account
entirely for measurement variability. If indicated, we substituted the
value equal to three times the RDL to apply as the adjusted MACT floor
or beyond the floor emissions limit. This adjusted value would ensure
measurement variability is adequately addressed in the MACT floor or
the beyond the floor emissions limit.
For HCl, three times the RDL was less than the calculated 99
percent UPL for exhaust HCl concentration from existing furnaces. Thus,
for existing sources, the MACT floor for HCl is set at the UPL, or 809
[micro]g/dscm corrected to 2 percent CO2.
Consistent with CAA section 112(d)(3), the MACT floor for new
sources cannot be less stringent than the emissions control that is
achieved in practice by the best-controlled similar source. The 99
percent UPL calculated for HCl based on the best performing source is
less stringent than the MACT floor for HCl at existing furnaces. We
determined that the use of the best performing source UPL is not
appropriate in this situation because the high variability and small
data pool would result in a new source MACT floor limit that is less
stringent than the limit based on the UPL calculated from the larger
data pool for existing sources. Given that the 99 percent UPL for new
sources is higher than the 99 percent UPL for existing sources, we
determined that the MACT limit for new sources should be equal to the
MACT limit for existing sources.
We then considered a beyond-the-floor option to further reduce
emissions of HCl at existing sources based on application of additional
add-on control devices, such as lime injection, but their use is not
indicated given the high costs of installing and operating such
controls. There is also concern that use of this technology could
prevent the current practice of reusing or selling baghouse dust and
the resulting waste reduction benefits. See the Draft MACT Floor
Analysis for the Ferroalloys Production Source Category in the docket
for more discussion of this topic.
Therefore, pursuant to CAA sections 112(d)(2) and 112(d)(3), we are
proposing to revise the 1999 NESHAP to include emission limits for new
and existing sources for HCl of 809 [micro]g/dscm. At this level, we do
not anticipate that either source would be required to install controls
to meet the limits. For more information on how these limits were
derived, see the Draft MACT Floor Analysis for the Ferroalloys
Production Source Category. As described above, there are some
measurements (i.e., 50 percent) reported as below the method detection
level. Because of the potential uncertainty in basing a limit partially
on non-detect values, we considered the possibility of proposing work
practice standards such as a limit on the amount of coal (the primary
source of chlorine in the raw materials) in lieu of numerical emission
limits. We request comment on whether this or other work practices
might be appropriate.
4. Formaldehyde
Formaldehyde emissions are also products of incomplete combustion
from the smelting operation. Based on test data from the ICR, we
estimate that the two facilities in this source category emit
approximately 2 tpy of formaldehyde. Pursuant to CAA section 112(d)(2)
and 112(d)(3), we are proposing to revise the 1999 NESHAP to include
emission limits for formaldehyde.
The measured average formaldehyde emissions ranged from 57 to 78
[micro]g/dscm corrected to 2 percent CO2. Because the
formaldehyde emissions data included some data points (50 percent)
reported as below the detection limit, we employed a version of the
methodology used for HCl to determine the MACT floor. However, in this
case we lack the underlying large data set of formaldehyde method
detection limits that we had for HCl method detection limits. In this
case, the first step was to define a method detection level that is
representative of the data used in defining the best performers for the
inclusive source category (i.e., combined data for all subcategories).
We identified all of the available reported pollutant specific method
detection levels and calculated the arithmetic mean value. We deemed
the resulting mean of the method detection levels as the (RDL). Three
times the RDL was
[[Page 72528]]
greater than the calculated 99 percent UPL for exhaust formaldehyde
concentrations from existing furnaces, resulting in a MACT floor of
three times the RDL, or 201 [micro]g/dscm at 2 percent CO2.
Based on available data, all of the existing sources could meet this
limit without installing additional controls.
Due to the high variability in the data pool, the 99 percent UPL
for the best-performing source is less stringent than the existing
source MACT floor. Therefore, pursuant to CAA section 112(d)(2) and
112(d)(3), we are proposing to revise the 1999 NESHAP to include an
emission limit for formaldehyde for new and existing sources of 201
[micro]g/dscm based on the MACT floor calculation. We have not
identified any appropriate beyond-the-floor control technology options
specifically for formaldehyde. We recognize the potential for some co-
control of formaldehyde emissions that would be achieved by using
activated carbon injection to control mercury emissions, but we were
unable to quantify those reductions. More information regarding how the
MACT limits were calculated and the costs is provided in Ferroalloys
Production MACT Floor and Cost Memos, which are available in the docket
for this rulemaking. Finally, because of the potential uncertainty in
basing a limit partially on non-detect values, we considered the
possibility of proposing work practice standards. We request comment on
whether there are any work practices that might be appropriate.
B. What are the results of the risk assessment and analyses?
As described above, for the Ferroalloys Production source category,
we conducted an inhalation risk assessment for all HAP emitted. We also
conducted multipathway screening analyses for mercury and POM. Details
of the risk assessment and additional analyses can be found in the
residual risk documentation referenced in section III.B of this
preamble, which is available in the docket for this action. The Agency
considered the available health information--the MIR; the numbers of
persons in various risk ranges; cancer incidence; the maximum non-
cancer HI; the maximum worst-case acute non-cancer HQ; the extent of
non-cancer risks; the potential for adverse environmental effects; and
distribution of risks in the exposed population (54 FR 38044, September
14, 1989) in developing the proposed CAA section 112(f)(2) standards
for the Ferroalloys Production source category.
1. Inhalation Risk Assessment Results
Table 5 of this preamble provides an overall summary of the results
of the inhalation risk assessment.
Table 5--Ferroalloys Production Inhalation Risk Assessment Results
--------------------------------------------------------------------------------------------------------------------------------------------------------
Maximum individual cancer risk (in 1 Maximum chronic non-cancer TOSHI \3\
million) \1\ Estimated population Estimated annual -------------------------------------------- Maximum screening
------------------------------------------- at increased risk of cancer incidence acute non- cancer HQ
Based on actual Based on allowable cancer >= 1-in-1 (cases per year) Based on actual Based on allowable \4\
emissions level \2\ emissions level million emissions level emissions level
--------------------------------------------------------------------------------------------------------------------------------------------------------
80 100 26,000 0.002 90 200 10
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Estimated maximum individual excess lifetime cancer risk due to HAP emissions from the source category.
\2\ Based on the consistent views of major scientific bodies (i.e., NTP in their 12th Report on Carcinogens, IARC, and other international agencies)
that consider all nickel compounds to be carcinogenic, we currently consider all nickel compounds to have the potential of being as carcinogenic as
nickel subsulfide. To implement this approach we apply the nickel subsulfide IRIS URE without a factor to reflect the assumption that 100 percent of
the total mass of nickel may be carcinogenic. The EPA also considers it reasonable to use a value that is 50 percent of the IRIS URE for nickel
subsulfide for providing an estimate of the lower end of a plausible range of cancer potency values for different mixtures of nickel compounds. If the
lower end of the nickel URE range is used, the maximum individual lifetime cancer risk based on actual emissions would be 50 in 1 million. The
allowable cancer risk would remain 100 in a million because at one facility nickel is not the primary cancer driver. The estimated annual cancer
incidence would also be reduced, but due to our presentation of incidence to one significant figure, remains 0.002. Estimated population values are
not scalable with the nickel URE range, but would be lower using the lower value.
\3\ Maximum TOSHI. The target organ with the highest TOSHI for the Ferroalloys Production source category is the central nervous system.
\4\ The maximum off-site HQ acute value of 10 is driven by emissions of nickel. See section III.B of this preamble for explanation of acute dose-
response values.
The results of the chronic baseline inhalation cancer risk
assessment indicate that, based on estimates of current actual
emissions, the current maximum individual lifetime cancer risk posed by
these two facilities could be up to 80 in one million (50 in one
million with the lower nickel URE value), with process fugitive
emissions (from the furnace, crushing operation, and casting) of
nickel, chromium and arsenic as major contributors to the risk. The
total estimated cancer incidence from this source category based on
actual emission levels is 0.002 excess cancer cases per year or one
case in every 500 years, with emissions of nickel, chromium and arsenic
contributing 36 percent, 24 percent and 24 percent respectively, to
this cancer incidence. In addition, we note that approximately 1,100
people are estimated to have cancer risks greater than 10 in one
million, and approximately 26,000 people are estimated to have risks
greater than one in one million as a result of emissions from these two
facilities. When considering the risks associated with MACT-allowable
emissions, both facilities have allowable risks of 100 in one million,
driven by nickel, chromium VI, and arsenic at one facility (which would
have an allowable cancer risk of 70 in one million when using the lower
nickel URE value) and chromium VI and arsenic at the other facility
(which would have an allowable cancer risk of 100 in one million when
using the lower nickel URE value).
The maximum modeled chronic non-cancer TOSHI value for the source
category based on actual emissions could be up to 90 with emissions of
manganese from process fugitives contributing greater than 90 percent
of those impacts. A TOSHI of 90 means that the modeled long-term
average air concentration of manganese at that location is about 4.5
[micro]g/m\3\, or 90 times above the RfC (i.e., 0.05 [micro]g/m\3\).
Approximately 28,000 people are exposed to TOSHI levels above 1 and
approximately 30 people are exposed to a TOSHI greater than 10. When
considering MACT-allowable emissions, which did not adjust the fugitive
emissions, the maximum chronic non-cancer TOSHI value could be up to
200.
Our screening analysis for worst-case acute impacts indicates the
potential for two pollutants, nickel and arsenic, to exceed an HQ value
of 1, with a potential maximum HQ up to 10 for nickel and 9 for arsenic
based on acute REL values for each substance. There
[[Page 72529]]
are no AEGL, ERPG, or short-term occupational values for these
pollutants to use as comparison to acute REL values, as has been done
in other RTR actions. In addition, there are no reference values
available to assess any potential risks from acute exposure to
manganese. These acute result values were based on hourly emissions
estimates and a review of the facility boundaries to make sure the
estimated impacts were off facility property. Refer to Appendix 1 of
the Risk Assessment document in the docket for a detailed description
of how the hourly emissions were developed for this source category.
These results suggest there may be potential for acute impacts of
concern from the emissions of nickel and arsenic from the two
facilities in this category. In characterizing the potential for acute
noncancer impacts of concern, it is important to remember the upward
bias of these exposure estimates (e.g., worst-case meteorology
coinciding with a person located at the point of maximum concentration
during the hour) and to consider the results along with the
uncertainties related to the emissions estimates and the screening
methodology.
2. Multipathway Risk Screening and Results
The PB-HAP emitted by facilities in this category include mercury,
POM (as benzo(a)pyrene toxicity equivalents, or TEQ), and lead. To
identify potential multipathway health risks from PB-HAP other than
lead, we first performed a screening analysis that compared emissions
of other PB-HAP emitted from the Ferroalloys Production source category
to emission threshold values. The two facilities in the source category
reported emissions of mercury and POM, and both of them had baseline
emission rates greater than the screening emission threshold values for
the pollutants indicating that there may be potential multipathway
impacts of concern due to emissions of these pollutants from these two
facilities.
Since the two PB-HAP did not screen out during our initial
screening analysis, we refined our analysis somewhat with some
additional site-specific information to develop an ``intermediate
screen,'' which is a more realistic analysis but still considered a
screening analysis. (See Appendix 5 of the Risk Assessment document in
the docket for more information about this intermediate screen.) The
additional site-specific information included land use around the
facilities, the location of fishable lakes, and local wind direction
and speed. The result of this analysis was the development of site-
specific emission screening thresholds for POM and mercury. Based on
this intermediate screening analysis, neither facility screened out,
meaning that we cannot rule out the potential for multipathway impacts
of concern due to emissions of these pollutants from these two
facilities. We were unable to obtain the data necessary to conduct a
fully refined assessment of multipathway risks from these two
facilities.
In evaluating the potential for multipathway effects from emissions
of lead, modeled maximum annual lead concentrations were compared to
the National Ambient Air Quality Standards (NAAQS) for lead (0.15
[micro]g/m\3\). Results of this analysis estimate that the NAAQS for
lead could be exceeded at one of the two facilities, largely due to
process fugitive emissions. This analysis estimates that the annual
lead concentrations could be as high as two times the NAAQS for lead,
and if the maximum 3-month rolling average concentrations were used,
the result could be even greater concentrations above the NAAQS.
However, this additional analysis was not conducted because, as shown
below (in section IV.C.2), the maximum annual lead concentration after
the proposed controls are applied is significantly below the NAAQS,
with a value of 0.02 [micro]g/m\3\.
3. Facilitywide Risk Assessment Results
For both facilities in this source category, there are no other
significant HAP emissions sources present beyond those included in the
source category. All significant HAP sources have been included in the
source category risk analysis. Therefore, we conclude that the
facilitywide risk is essentially the same as the source category risk
and that no separate facilitywide analysis is necessary.
C. What are our proposed decisions based on risk acceptability and
ample margin of safety?
1. Risk Acceptability
As noted in section III.C of this preamble, we weigh all health
risk factors in our risk acceptability determination, including the
MIR; the number of persons in various cancer and noncancer risk ranges;
cancer incidence; the maximum noncancer HI; the maximum acute noncancer
HQ; the extent of noncancer risks; the potential for adverse
environmental effects; distribution of cancer and noncancer risks in
the exposed population; and risk estimation uncertainty (54 FR 38044,
September 14, 1989).
Based on the baseline inhalation risk assessment, we estimate that
the cancer risks to the individual most exposed could be up to 80 in
one million (50 in one million when using the lower nickel URE value)
due to actual emissions of arsenic, chromium and nickel from process
fugitives and up to 100 in one million due to MACT-allowable emissions,
mainly due to chromium, arsenic and nickel stack emissions. (There is
no change in the allowable cancer risk estimate when using the lower
nickel URE value.) We estimate that the incidence of cancer based on
actual emissions is 0.002 excess cancer cases per year, or 1 case every
500 years, and that about 26,000 people face a cancer risk greater than
one in one million due to HAP emissions from this source category. The
chronic noncancer TOSHI could be up to 90 due to actual emissions of
manganese from process fugitives and up to 200 due to MACT-allowable
emissions of manganese from process fugitives. We estimate that about
28,000 people face a TOSHI level greater than 1 and approximately 30
people face a TOSHI greater than 10 due to emissions from this source
category.
With respect to potential acute non-cancer health risks, we
estimate that, based on our refined analysis, the worst-case HQ value
could exceed an HQ value of 1 for two pollutants, nickel and arsenic,
with a potential maximum HQ up to 10 for nickel and 9 for arsenic. This
indicates a potential acute concern relative to the baseline emissions
of these two pollutants based on the REL. In characterizing the
potential for acute noncancer impacts of concern, it is important to
remember the upward bias of these exposure estimates and to consider
the results along with the uncertainties related to the emissions
estimates and screening methodology. In the case of ferroalloys, the
acute emissions estimates were based on actual data from the ICR (i.e.,
there was not an acute emissions adjustment factor). Our assessment
also indicates the potential for multipathway impacts of concern based
on the intermediate screening assessment due to baseline emissions of
mercury and POM. Data were unavailable to conduct a fully refined
assessment of multipathway risks from these two facilities.
The risk assessment for this source category was based on facility-
specific stack-test data and emissions estimates, giving us a generally
high degree of confidence in the results. We applied the two-step
analysis set out in the Benzene NESHAP to assess emissions from this
source category. Considering all of the above information, we are
proposing that the risks are
[[Page 72530]]
unacceptable, both for the actual emissions scenario and for the MACT-
allowable emissions scenario.
The proposed determination that risks are unacceptable for this
source category is primarily based on the fact that the maximum chronic
noncancer HI values (90 based on actual emissions, 200 based on
allowable, both dominated by manganese emissions) are higher than 1 (an
HI exposure level of 1 is generally considered to be without
appreciable risk of adverse health effects). The fact that 28,000
people are estimated to have exposures greater than an HI of 1 (based
on actual emissions) also weighs in this proposed determination. The
fact that maximum individual cancer risks are above 1 in a million also
contributes to our determination of unacceptability, but to a lesser
extent. While the estimated maximum individual cancer risks would, by
themselves, not generally lead us to a determination that risks are
unacceptable, the fact that they occur along with the chronic noncancer
TOSHI greater than 1 (approximately 28,000 people are exposed to TOSHI
levels above 1 and approximately 30 people are exposed to a TOSHI
greater than 10) adds to our concern about these exposures, and further
supports our proposed determination that risks are unacceptable. The
total estimated cancer incidence (0.002 cases per year) is not very
high, and this fact did not weigh significantly in our proposed
determination of unacceptable risk. However, in the past EPA has
weighed an estimated cancer incidence of 0.002 cases per year heavily
in a determination of acceptable risk. EPA notes that there were no
non-cancer concerns in these previous instances. We further note that,
while our screening for potential acute and multi-pathway impacts of
concern from the 2 sources in the category did identify some potential
concerns for a few HAPs, these screening results did not weigh heavily
in our proposed determination that risks are unacceptable.
Given that chronic noncancer risks associated with manganese
emissions are the primary determinant of unacceptable risks, we provide
here a brief discussion of the EPA's RfC associated with the inhalation
of manganese and our confidence in the principal studies supporting the
development of that RfC for context. The RfC is the level below which
there is not likely to be appreciable risk of deleterious effects;
however, the EPA cannot state at what exposure level there will be an
appreciable risk of deleterious effects. In the case of manganese, the
effect of concern was a decrease in visual reaction time in adults who
were occupationally exposed to manganese. The effects were seen at a
dose adjusted value of 0.05 mg/m\3\ and then to derive the RfC, the EPA
divided this value by 1000 to account for uncertainties related to
sensitive individuals (10x), use of the lowest exposure level at which
effects were observed in lieu of a level without effects (10x) and due
to database limitations (10x). We note that the concentration reflected
in the maximum TOSHI of 90 (0.0045 mg/m\3\) is approximately a factor
of 10 lower than the 0.05 mg/m\3\ dose adjusted effect level in an
adult male work force and used in the derivation of the RfC (0.00005
mg/m\3\). The EPA has ``medium confidence'' (as used and described in
the IRIS database) in the RfC value of 0.00005 mg/m\3\. The confidence
level reflects the overall level of uncertainty in the principle
studies, which were based on human occupational studies, and the
database.
Overall confidence in the principal studies (Roels et al., 1987,
1992) is ``medium''. Neither of the principal studies identified a no
observed adverse effect level (NOAEL) for neurobehavioral effects, nor
did either study directly measure particle size or provide information
on the particle size distribution. The 1992 study by Roels et al. did
provide respirable and total dust measurements, but the 1987 study
measured only total dust.\35\ These limitations of the studies are
mitigated by the fact that the principal studies found similar
indications of neurobehavioral dysfunction, which was consistent with
the results of other human studies. In addition, the 1992 Roels et al.
study provides sufficient information to establish individual
integrated exposures; the 1987 Roels et al. study did not.
---------------------------------------------------------------------------
\35\ ``Total and respirable dust concentrations were highly
correlated, with the Mn content of the respirable fraction
representing on average 25% of the manganese content in the total
dust. The RfC is based on the respirable fraction.
---------------------------------------------------------------------------
Confidence in the database on manganese health effects is
``medium''. The duration of exposure was relatively limited and the
workers were relatively young in all of the principal and supporting
studies. These temporal limitations raise concerns that longer
durations of exposure and/or interactions with aging might result in
the detection of effects at lower concentrations, as suggested by
results from other studies. In addition, the studies, with the
exception of the 1992 Roels et al. study in which manganese exposure
was limited to manganese oxide, did not specify the species of
manganese to which workers were exposed. It is not clear whether
certain compounds or oxidation states of manganese are more toxic than
others. Although the primary neurotoxicological effects of exposure to
airborne manganese have been qualitatively well characterized by the
general consistency of effects across studies, the exposure-effect
relationship remains to be well quantified, and a no-effect level for
neurotoxicity has not been identified in any of these studies thus far.
Finally, the effects of manganese on development and reproduction have
not been studied adequately. See the full IRIS summary for manganese
for more information (IRIS, Manganese, available at: www.epa.gov/iris/subst/0373.htm).
As noted in the 1989 Benzene NESHAP, the Agency weighs multiple
risk factors in making a determination of acceptable or unacceptable
risk, and notes that acceptability cannot be reduced to any single
factor. In applying the balancing factors to this action, EPA
considered a wide range of data including the MIR; the number of
persons in various cancer and noncancer risk ranges; cancer incidence;
the maximum noncancer HI; the maximum acute noncancer HQ; the extent of
noncancer risks; the potential for adverse environmental effects;
distribution of cancer and noncancer risks in the exposed population;
and risk estimation uncertainty (54 FR 38044, September 14, 1989).
In summary, the MIR was 80 in a million based on actual emissions
and 100 in one million based on allowable emissions; the total
estimated cancer incidence was 0.002 cases per year (or 1 case in every
500 years); and approximately 30 people could be exposed at a TOSHI
greater than 10 while approximately 28,000 could be exposed at a TOSHI
greater than 1. Since the RfC is 1000 fold below the lowest level at
which neurological effects were seen, the maximum TOSHI of 90 (or 200
for allowable risks) is still below the effect level used to derive the
RfC and there is uncertainty as to exactly what level of exposure above
the RfC will lead to appreciable risk of adverse effects. The
population from which the effect level was derived was an adult male
worker population, and that this population does not necessarily
represent the general population. We note that the concentration
reflected in the maximum TOSHI of 90 (0.0045 mg/m\3\) is approximately
a factor of 10 lower than the 0.05 mg/m\3\ dose adjusted effect level
in an adult male work force which was used in the derivation of the
RfC.
[[Page 72531]]
Based on our assessment of the information, we are proposing that
the risks are unacceptable. We solicit comment on all aspects of this
proposed determination. Specifically, we solicit any information (and
supporting data) that would further inform our proposed decision.
We also solicit comment on whether an alternative balancing of all
the same factors including the weights afforded to individual factors
discussed above and their associated uncertainties could lead to a
different decision regarding risks. EPA also solicits any information
(and supporting data) that would further inform this alternative
approach.
Under the two-step Benzene NESHAP approach, we are required under
CAA section 112(f)(2)(A) to make a determination as to what controls
are needed to achieve an ample margin of safety for the source category
after we make a determination on risk acceptability. The discussion of
the controls needed to achieve an ample margin of safety in section
IV.C.3 addresses both what would be needed if we find risks are
unacceptable as well as what would be needed if we find that risks are
acceptable.
2. Proposed Controls To Address Risks
We conducted an assessment to estimate the risks from the two
facilities in the source category based on a post-control scenario
reflecting the proposed requirements described above to address
unregulated HAP (section IV.A) and the proposed controls described
below. Details are provided in the Draft Risk Assessment report which
is available in the docket for this action.
a. Allowable Stack Emissions
In order to ensure that the risks associated with this source
category are acceptable, we evaluated the potential to reduce MACT-
allowable stack emissions, which had driven the cancer MIR based on
allowable emissions to 100 in a million, primarily due to allowable
stack emissions of arsenic, nickel and chromium, and contributed
significantly to the chronic noncancer TOSHI (based on allowable
emissions) of 200, primarily due to allowable stack emissions of
manganese. Our analysis determined that we could lower the existing
particulate matter emission limits by approximately 50 percent for
furnace stack emissions, by 80 percent for crushing and screening stack
emissions and by 98 percent for the metal oxygen refining process.
After the implementation of these tighter PM stack limits, the
estimated cancer MIR for the source category based on allowable
emissions would become 80 in one million and the TOSHI would be about
90.
For the reasons described above, under the authority of CAA section
112(f)(2), we propose to set particulate matter emission limits for the
stacks at the following levels: 9.3 mg/dscm corrected to 2 percent
CO2 for new or reconstructed electric arc furnaces, 24 mg/
dscm corrected to 2 percent CO2 for existing electric arc
furnaces, 1.5 mg/dscm corrected to 2 percent CO2 for any
new, reconstructed or existing MOR process, and 13 mg/dscm for any new,
reconstructed or existing crushing and screening equipment. We believe
sources can achieve these limits with existing controls. These new
emissions limits will reduce potential risks due to allowable emissions
from the stacks and prevent backsliding. We propose that compliance for
existing sources will be demonstrated by annual stack testing and
installation and operation of bag leak detection systems for both new
and existing sources.
b. Process Fugitive Emissions Sources
Process fugitive sources are partially controlled by the existing
MACT via a shop building opacity standard; however, that standard was
only intended to address tapping process fugitives generated under
``normal'' tapping process operating conditions. Casting and crushing
and screening process fugitives in the furnace building were not
included. Under the authority of section 112(d)(2) of the Act, which
allows the use of measures to enclose systems or processes to eliminate
emissions and measures to collect, capture or treat such pollutants
when released from a process, stack, storage, or fugitive emissions
point, we evaluated several options to achieve improved emissions
capture. We developed several control scenarios to assess options to
improve/add local ventilation and associated control (e.g., improve
tapping capture, install capture and control on casting operations),
but we concluded that these were all ineffective in significantly
reducing emissions and risks. As part of the technology review process,
we identified a furnace building ventilation system at a non-manganese
producer of ferroalloys. We evaluated an option based on this furnace
building ventilation system, which involves enclosing the furnace
building(s) and evacuating the emissions to a control device(s). Based
on our assessment we conclude that this option would reduce process
fugitive emissions by about 98 percent and reduce the maximum noncancer
TOSHI to about 2. A TOSHI of 2 means that the modeled long-term
concentration of manganese at that location would be about 0.1
[micro]g/m\3\ (i.e., about 2 times higher than the RfC). These controls
would also significantly reduce the emissions of arsenic, chromium and
nickel and therefore significantly reduce the cancer risks. These
reductions would result in acceptable risk levels. Therefore, under the
authority of CAA section 112(f), we are proposing such an approach,
whereby the furnace buildings must be enclosed and process fugitive
emissions would need to be collected under negative pressure at the
ridge vents of the shop building and ducted to a control device.
We are proposing that the PM emissions limit (as a surrogate for
particulate metal HAP) at the control device would be the same as it is
for the furnace stacks (24 mg/dscm). This would allow sources the
option to duct some or all process fugitive emissions to an existing
furnace control device if it has excess capacity. If the existing
control device at the facility does not have sufficient excess capacity
to handle the captured emissions, the facility would have to install
additional controls capable of complying with the proposed emission
limit.
The source would also have to monitor building opacity, prepare and
operate according to a process fugitives ventilation plan and conduct
annual performance testing of the building ventilation control device
to demonstrate compliance with the proposed standards. Baghouses would
be required to be equipped with BLDS. We also propose that facilities
would need to continue the practices to minimize outdoor fugitive dust
emissions that are required by the 1999 MACT rule which includes
implementing measures specified in their outdoor fugitive dust control
plans as approved by the Administrator.
However, recognizing that there may be other control measures that
could achieve equivalent emissions reductions that we have not yet
identified, and to provide some flexibility for facilities to determine
the best approach to reduce their emissions, we are also proposing an
equivalent alternative compliance approach. Under this alternative
approach, we propose that facilities would still need to continue the
work practices to minimize outdoor fugitive dust emissions that are
required by the 1999 MACT rule which includes implementing measures
specified in their outdoor fugitive dust control plans as approved by
the Administrator. However, in lieu of building the full enclosure and
capture and evacuation system described above to control
[[Page 72532]]
process fugitive emissions, we are proposing that facilities can design
and implement an equivalent alternative approach (e.g., local capture,
controls, and work practices) to address the risks associated with
those process fugitive emissions. Compliance would be demonstrated by
ensuring facilities apply the equivalent alternative approach to
control process fugitive emissions, continue the work practices to
minimize outdoor fugitive dust emissions, and also conduct fenceline
monitoring to demonstrate that the ambient concentration of manganese
at their facility boundary is no more than 0.1 [mu]g/m\3\ on a 60-day
rolling average, as described below.
Specifically, we propose to require that sources seeking to use
this alternative prepare and submit for the Administrator's approval a
written plan describing and explaining the equivalent alternative
approach that they propose to apply and a proposed compliance
monitoring network that must consist of at least two monitors located
at or near the facility boundary, and in locations expected to have the
highest concentrations of manganese, and the procedures for sampling,
sample handling and custody, sample analysis, quality assurance, and
recordkeeping procedures. The purpose of the ambient air monitoring
network would be to ensure that manganese concentrations in air near
the facility boundaries remain at or below 0.1 [mu]g/m\3\ based on 10-
sample rolling averages, with samples being collected every 6 days
(i.e., 60-day rolling averages). The monitoring plan must include a
minimum of two monitoring sites that are placed in locations that are
most likely to capture measurements of the maximum concentrations at or
near the facility boundaries. For example, at least one monitor must be
placed in the predominant downwind direction from main emissions
sources based on historical weather patterns in the area. This standard
for manganese emissions would be a surrogate for all particulate HAP
metals (including arsenic, nickel and chromium) since they are emitted
by the same processes and controlled with the same devices and
measures. We propose to set this alternative limit using manganese as a
surrogate for metal HAP because manganese is the primary HAP metal
emitted from this source category. We considered the feasibility of
using PM as a surrogate, but developing a reliable relationship between
fenceline manganese concentration and filterable PM concentration is
almost impossible. We request comment on the use of manganese as a
surrogate for HAP metals in the alternative approach.
This alternative regulatory requirement would provide flexibility
to facilities in determining the within-facility emission sources that
should be captured and vented to a control device that are most
effective for reducing process fugitive emissions at their facilities.
However, any facility considering this alternative approach would need
to demonstrate that they can be expected to achieve the fenceline
limitation with the proposed alternative approach and obtain approval
from the Administrator. This is especially important for facilities
with a history of elevated ambient manganese concentrations based on
monitoring by state regulatory agencies or the EPA, or any facility
that has been confirmed as the main contributor to elevated monitored
manganese concentrations in a particular area. Nevertheless, we are
seeking comments on this proposed alternative requirement, including
the controls and practices that can achieve the equivalent level of
reductions, the averaging time for monitoring, and whether two monitors
would be sufficient or if more monitors may be warranted.
We propose to set the fenceline concentration level at 0.1 [mu]g/
m\3\ to reflect the equivalent level of emissions control that we
estimate will be achieved with the requirement to enclose the furnace
building(s) and evacuate the emissions to a control device(s). As
described in section IV.D.2, the maximum modeled chronic noncancer
inhalation TOSHI value is 2 after full enclosure and evacuation of
emissions based on the post-control modeling analysis. This means that
the modeled concentration at the maximum impact location after these
controls are in place would be 0.1 [mu]g/m\3\, which is 2 times higher
than the value of the RfC for manganese. Therefore, achieving and
maintaining an air manganese level of 0.1 [mu]g/m\3\ at the facility
boundary is proposed as the equivalent alternative standard to minimize
emissions of HAP metals. Nevertheless, we request comment on other
concentration values that might be appropriate to serve as the
concentration level for fenceline monitoring under this alternative. We
also request comment on whether a different averaging period should be
required.
As part of this alternative, we are also proposing a provision that
would allow for reduced monitoring if the facility demonstrates ambient
manganese concentrations less than 50 percent of the ambient manganese
concentration limit for 3 consecutive years at each monitor. We propose
that a revised monitoring plan may be submitted (for review and
possible approval by the Administrator) to reduce the sampling and
analysis frequency if all of the 10-sample rolling average
concentrations at each monitor are less than 50 percent of the limit of
0.1 [mu]g/m\3\ over a 3-year period.
All of these proposed controls are described further under the
technology review (in section IV.D.2.) of this preamble.
c. Results of the Post-Control Risk Assessment
The results of the post-control chronic inhalation cancer risk
assessment indicate that, based on actual emissions, the maximum
individual lifetime cancer risk posed by these two facilities, after
the implementation of the proposed controls, could be up to 5 in one
million, reduced from 80 in one million (i.e., pre-controls), with an
estimated reduction in cancer incidence to 0.0004 excess cancer cases
per year, reduced from 0.002 excess cancer cases per year. In addition,
the number of people estimated to have a cancer risk greater than or
equal to one in one million would be reduced from 26,000 to 1,300.
The results of the post-control assessment also indicate that,
based on actual emissions, the maximum chronic noncancer inhalation
TOSHI value would be reduced to 2, from the baseline estimate of 90.
The number of people estimated to have a TOSHI greater than 1 would be
reduced from 28,000 to less than 10.
We also estimate that after the implementation of controls, the
maximum worst-case acute refined HQ value would be reduced from a
potential high of 10 to 0.3 (based on the REL value for nickel
compounds) eliminating any potential for acute impacts of concern.
Considering post-control emissions of multipathway HAP, mercury
emissions would be reduced approximately 88 percent, while POM
emissions would be reduced approximately 66 percent from the baseline
emission rates. Based on our intermediate screening approach for
multipathway risks, emissions of mercury ``screen out,'' or are reduced
below the screening threshold for both facilities, indicating no
potential for multipathway impacts of concern due to mercury. However,
emissions of POM (as benzo(a)pyrene TEQ) remain above the intermediate
screening thresholds for both facilities (one by a factor of 20 and one
by a factor of 2), indicating that we cannot rule out the potential for
multipathway impacts of concern due to emissions of POM from these
facilities.
[[Page 72533]]
As mentioned above, the highest lead concentration after controls, 0.02
[mu]g/m\3\, is well below the NAAQS, indicating a low potential for
multipathway impacts of concern due to lead.
3. Ample Margin of Safety Analysis and Proposed Controls
Under the ample margin of safety analysis, we evaluate the cost and
feasibility of available control technologies and other measures
(including the controls, measures and costs reviewed under the
technology review) that could be applied in this source category to
further reduce the risks due to emissions of HAP identified in our risk
assessment.
We estimate that the actions proposed under CAA section 112(f)(2),
as described above to address unacceptable risks, will reduce the MIR
associated with arsenic, nickel and chromium from 80 in one million (50
in one million using the lower end of the nickel URE range) to 5 in one
million for actual emissions. The cancer incidence will be reduced from
0.002 to 0.0004, and the number of people estimated to have cancer
risks greater than one in one million will be reduced, from 26,000
people to 1,300 people. The chronic noncancer inhalation TOSHI will be
reduced from 90 to 2, and the number of people exposed to a TOSHI level
greater than 1 will be reduced from 28,000 people to less than 10
people. In addition, the maximum acute HQ value will be reduced from
potentially up to 10 to less than 1, and the potential multipathway
impacts will be reduced.
Based on all of the above information, we conclude that the risks
after implementation of the proposed controls are acceptable. Based on
our research and analysis, we did not identify any cost-effective
controls beyond those proposed above that would achieve further
reduction in risk. Therefore we conclude that the controls to achieve
acceptable risks (described above) will also achieve an ample margin of
safety. Although we conclude that the implementation of the proposed
requirements described above will provide public health protection with
an ample margin of safety we acknowledge that there may be other
control technologies that may also achieve these goals.
We are soliciting comments and information regarding additional
dust and process fugitive control measures and work practices that may
be more feasible to implement and effective in further reducing process
and dust fugitive emissions of metal HAP, or additional monitoring that
may be warranted to ensure adequate control of fugitive emissions. We
also request comments on the cost effectiveness of achieving the
proposed process fugitive control measures and any additional options
that may be more cost effective.
We also note that we are soliciting comment on our proposed risk
finding. If we conclude, after evaluating data and information received
in comments on this proposed rule, that the risks posed by this source
category are acceptable, then based on the data and information we
currently have, we would likely adopt the same controls described in
section IV.C.2 as being necessary to provide an ample margin of safety.
As noted above in this section and in section IV.C.2.c., the proposed
controls provide significant risk reductions beyond the current rule.
Furthermore, as discussed more extensively in section IV.D.2 of this
notice, below, we conclude that these controls are cost effective and
technically feasible. We solicit comment on the appropriateness of
these controls in the event we find, based on data and information
received in comment, that the current rule provides an acceptable risk.
D. What are the results and proposed decisions based on our technology
review?
Based on our technology review, we determined that there have been
advances in emissions control measures since the Ferroalloys Production
NESHAP was originally promulgated in 1999. Since promulgation,
facilities have steadily improved the performance of their control
devices through upgrades or replacements. They have also developed
improved capture techniques for some process fugitives (e.g., casting
and tapping emissions). Additional details regarding these analyses can
be found in the following technical document for this action which is
available in the docket: Draft Technology Review for the Ferroalloys
Production Source Category.
1. Metal HAP Emissions From Stacks
We propose to continue to use particulate matter as a surrogate for
metal HAP other than mercury. For a discussion regarding the
appropriateness of particulate matter as a surrogate for non-mercury
metal HAP, please see the memo ``Surrogate for Metal HAP Emissions for
the Ferroalloys Source Category'' in the docket for this proposed rule.
Based on the results from the ICR test program, we determined that all
of the sources of stack emissions are emitting at significantly lower
levels than their maximum permitted levels. For this reason, under the
authority of CAA section 112(d)(6), we are proposing revised emission
limits for new and existing sources. We are also proposing that any
uncontrolled furnace vent stacks would be subject to the same
concentration limits.
We calculated the proposed emission limits based on a UPL analysis,
resulting in a proposed existing source furnace stack emissions limit
of 24 mg/dscm and proposed new source furnace stack emissions limit of
9.3 mg/dscm. We also calculated a proposed stack emission limit of 13
mg/dscm for crushing and screening equipment that would apply to both
new and existing sources.
The metal oxygen refining operation is a unique process, and so we
only have a single ICR test data point. Therefore, we calculated a
proposed emissions limit for this source using the 99 percent UPL from
the test data, resulting in a proposed limit of 3.9 mg/dscm that would
apply to new and existing metal oxygen refining operation sources. We
request comment on whether we should instead set the MOR limit to be
the same as the proposed furnace stack limit for existing sources. This
change would allow a facility to use any excess capacity in the MOR
control device to treat furnace emissions, if needed. Such a limit is
still more stringent than the current limit included in subpart XXX for
the MOR (approximately 69 mg/dscm).
Based on our analyses, we expect that no additional controls would
be required for the facilities to comply with these proposed limits. To
demonstrate compliance, we propose that sources would be required to
conduct periodic performance testing, and develop and operate according
to a baghouse operating plan or continuously monitor scrubber operating
parameters. Furnace baghouses would be required to be equipped with bag
leak detection systems (BLDS).
2. Metal HAP Emissions From Process Fugitives
As described above, we evaluated several options to improve and
increase the capture and control of process fugitive sources. The two
main options involve either local ventilation or building ventilation.
Local ventilation (e.g., hoods or ductwork located in close proximity
to an emissions source such as tapping or casting) is common in this
industry, but performance varies due to design of the capture system,
maintenance practices and control device capacity. Industry
representatives have expressed concern that extensive retrofitting of
local ventilation is complicated at existing facilities because of the
need for
[[Page 72534]]
material movement using large overhead cranes and ladles. We identified
a furnace building ventilation system at a ferrosilicon producer, using
a similar production process. This ``system'' is basically an enclosure
of the furnace building with evacuation of emission to a control
device.
We evaluated an option to enclose the furnace building(s) and
evacuate the emissions to a control device(s) similar to the system
used at the ferrosilicon producing facility described above. Based on
that evaluation, we believe that it is feasible to install enclosures
and have the fugitive emissions at the ridge vents of the shop building
collected under negative pressure and ducted to a control device, and
have a PM emissions limit at the control device the same as it is for
the furnace stacks (i.e., 24 mg/dscm). This would allow sources the
option to duct some or all process fugitive emissions to an existing
furnace control device if it has excess capacity. If it does not have
excess capacity, the facility would have to install additional
controls. Under this option, the source would also have to monitor
building opacity; prepare and operate according to a process fugitives
emissions ventilation plan, which would include requirements to
demonstrate that the building is being operated at a negative pressure
of at least 0.007 inches of water; and conduct periodic performance
testing of the building ventilation control device to demonstrate
compliance with the proposed standards. Baghouses would be required to
be equipped with BLDS.
We estimate the total capital costs of installing the required
ductwork, fans, and baghouses under this option to be $9.4 million and
the total annualized costs to be $2.3 million for the two plants. We
estimate that particulate metal HAP emissions would be reduced by 81
tons, resulting in a cost per ton of HAP removed at $28,000 per ton
($14 per pound). We also estimate that this option would achieve PM
emission reductions of 630 tons, resulting in a cost per ton of PM
removed at $3,600 per ton and achieve PM2.5 emission
reductions of 257 tons, resulting in a cost per ton of PM2.5
removed of $8800 per ton. In light of the technical feasibility and
cost effectiveness of this approach, we are proposing this option under
the authority of section 112(d)(6). These proposed requirements are
exactly the same as those proposed under Section 112(f) which are
described in section IV.C.2 of this preamble.
As described above in section IV.C.2.b, we are also proposing an
equivalent alternative compliance approach. Facilities can design and
implement an equivalent alternative approach (e.g., local capture,
controls, and work practices) to achieve equivalent reductions of their
process fugitive emissions. Compliance would be demonstrated by
ensuring facilities apply the equivalent alternative approach to
control process fugitive emissions, continue the work practices to
minimize outdoor fugitive dust emissions, and also conduct fenceline
monitoring to demonstrate that the ambient concentration of manganese
at their facility boundary is no more than 0.1 [mu]g/m\3\ on a 60-day
rolling average.
3. Hydrochloric Acid, Formaldehyde, Mercury and PAH Emissions From
Furnace Stacks
The controls for HCl, formaldehyde, mercury and PAHs were described
in Section IV.A., and no additional controls have been identified.
4. Outdoor Fugitive Dust Emissions
The existing rule has a requirement for an outdoor fugitive dust
control plan. We are unable to quantify HAP emissions from outdoor
fugitive dust sources and did not identify any additional procedures or
controls that could be expected to have a significant impact on these
emissions. Therefore, we are not proposing to change the existing
requirements.
E. What other actions are we proposing?
1. Startup, Shutdown, Malfunction
The United States Court of Appeals for the District of Columbia
Circuit vacated portions of two provisions in the EPA's CAA section 112
regulations governing the emissions of HAP during periods of SSM.
Sierra Club v. EPA, 551 F.3d 1019 (DC Cir. 2008), cert. denied, 130 S.
Ct. 1735 (U.S. 2010). Specifically, the Court vacated the SSM exemption
contained in 40 CFR 63.6(f)(1) and 40 CFR 63.6(h)(1), that are part of
a regulation, commonly referred to as the ``General Provisions Rule,''
that the EPA promulgated under CAA section 112. 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) emissions standard during
periods of SSM.
We are proposing the elimination of the SSM exemption in this rule.
Consistent with Sierra Club v. EPA, the EPA is proposing standards in
this rule that apply at all times. We are also proposing several
revisions to Table 1 to subpart XXX of part 63 (the General Provisions
Applicability table). For 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 related to the SSM exemption.
The 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 the standards in this rule, the 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 received from the
industry in the ICR indicate that emissions during these periods do not
increase. Control devices such as baghouses for metal HAP particulate
control and activated carbon controls for mercury are started up before
the process units, and are operational during the shutdown phase of a
process. Therefore, no increase in emissions is expected during these
periods. Building ventilation systems for process fugitive emissions
will be in place at all times. 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
usual manner * * *'' (40 CFR 63.2). The EPA has determined that CAA
section 112 does not require that emissions that occur during periods
of malfunction be factored into development of CAA section 112
standards. Under CAA section 112, emissions standards for new sources
must be no less stringent than the level ``achieved'' by the best
controlled similar source, and emission standards for existing sources
generally must be no less stringent than the average emissions
limitation ``achieved'' by the best performing 12 percent (or 5 sources
in cases where there are fewer than 30 sources in the source category)
of sources in the category. There is nothing in CAA section 112 that
directs the Agency to consider malfunctions in determining the level
``achieved'' by the best performing or best controlled sources when
setting emissions
[[Page 72535]]
standards. Moreover, while the EPA accounts for variability in setting
emissions standards consistent with the CAA section 112 case law,
nothing in that case law requires the Agency to consider malfunctions
as part of that analysis. Section 112 of the CAA uses the concept of
``best controlled'' and ``best performing'' unit in defining the level
of stringency that CAA section 112 performance standards must meet.
Applying the concept of ``best controlled'' or ``best performing'' to a
unit that is malfunctioning presents significant difficulties, as
malfunctions are sudden and unexpected events.
Further, accounting for malfunctions would be difficult, if not
impossible, given the myriad different types of malfunctions that can
occur across all sources in the category and given the difficulties
associated with predicting or accounting for the frequency, degree, and
duration of various malfunctions that might occur. As such, the
performance of units that are malfunctioning is not ``reasonably''
foreseeable. See, e.g., Sierra Club v. EPA, 167 F. 3d 658, 662 (DC Cir.
1999) (The EPA typically has wide latitude in determining the extent of
data-gathering necessary to solve a problem. We generally defer to an
agency's decision to proceed on the basis of imperfect scientific
information, rather than to ``invest the resources to conduct the
perfect study.'') See also, Weyerhaeuser v. Costle, 590 F.2d 1011, 1058
(DC 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''). In addition, the goal of a best controlled or
best performing source is to operate in such a way as to avoid
malfunctions of the source and accounting for malfunctions could lead
to standards that are significantly less stringent than levels that are
achieved by a well-performing non-malfunctioning source. The EPA's
approach to malfunctions is consistent with CAA section 112 and is a
reasonable interpretation of the statute.
In the event that a source fails to comply with the applicable CAA
section 112(d) standards as a result of a malfunction event, the 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.
The 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, the EPA recognizes that even equipment that is properly
designed and maintained can sometimes fail and that such failure can
sometimes cause an exceedance of the relevant emissions 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)). The EPA is therefore proposing to add to
the final rule an affirmative defense to civil penalties for
exceedances of emissions limits that are caused by malfunctions. See 40
CFR 63.1622 (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 40 CFR 63.1627 (40 CFR 22.24). The criteria ensure that the
affirmative defense is available only where the event that causes an
exceedance of the emissions limit meets the narrow definition of
malfunction in 40 CFR 63.2 (sudden, infrequent, not reasonable
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, 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 40
CFR 63.1623(g) 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 emissions
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 CAA
section 113 (see also 40 CFR 22.27).
The EPA included an affirmative defense in the proposed rule in an
attempt to balance a tension, inherent in many types of air regulation,
to ensure adequate compliance while simultaneously recognizing that
despite the most diligent of efforts, emission limits may be exceeded
under circumstances beyond the control of the source. The EPA must
establish emission standards that ``limit the quantity, rate, or
concentration of emissions of air pollutants on a continuous basis.''
42 U.S.C. 7602(k) (defining ``emission limitation and emission
standard''). See generally Sierra Club v. EPA, 551 F.3d 1019, 1021 (DC
Cir. 2008). Thus, the EPA is required to ensure that section 112
emissions limitations are continuous. The affirmative defense for
malfunction events meets this requirement by ensuring that even where
there is a malfunction, the emission limitation is still enforceable
through injunctive relief. While ``continuous'' limitations, on the one
hand, are required, there is also caselaw indicating that in many
situations it is appropriate for the EPA to account for the practical
realities of technology. For example, in Essex Chemical v. Ruckelshaus,
486 F.2d 427, 433 (DC Cir. 1973), the DC Circuit acknowledged that in
setting standards under CAA section 111 ``variant provisions'' such as
provisions allowing for upsets during startup, shutdown and equipment
malfunction ``appear necessary to preserve the reasonableness of the
standards as a whole and that the record does not support the `never to
be exceeded' standard currently in force.'' See also, Portland Cement
Association v. Ruckelshaus, 486 F.2d 375 (DC Cir. 1973). Though
intervening caselaw such as Sierra Club v. EPA and the CAA 1977
amendments undermine the relevance of these cases today, they support
the EPA's view that a system that incorporates some level of
flexibility is reasonable. The affirmative defense simply provides for
a defense to civil
[[Page 72536]]
penalties for excess emissions that are proven to be beyond the control
of the source. By incorporating an affirmative defense, the EPA has
formalized its approach to upset events. In a Clean Water Act setting,
the Ninth Circuit required this type of formalized approach when
regulating ``upsets beyond the control of the permit holder.'' Marathon
Oil Co. v. EPA, 564 F.2d 1253, 1272-73 (9th Cir. 1977). But see,
Weyerhaeuser Co. v. Costle, 590 F.2d 1011, 1057-58 (DC Cir. 1978)
(holding that an informal approach is adequate). The affirmative
defense provisions give the EPA the flexibility to both ensure that its
emission limitations are ``continuous'' as required by 42 U.S.C.
7602(k), and account for unplanned upsets and thus support the
reasonableness of the standard as a whole.
Specifically, we are proposing the following changes to the rule.
Added general duty requirements in 40 CFR 63.1623(g) to
replace General Provision requirements that reference vacated SSM
provisions.
Added replacement language that eliminates the reference
to SSM exemptions applicable to performance tests in 40 CFR
63.1625(a)(5).
Added paragraphs in 40 CFR 63.1629(d) requiring the
reporting of malfunctions as part of the affirmative defense
provisions.
Added paragraphs in 40 CFR 63.1629(b) requiring the
keeping of certain records during malfunctions as part of the
affirmative defense provisions.
Developed Table 1 to subpart XXX of part 63 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. Electronic Reporting
The EPA and other authorities such as state, local and tribal
agencies must have performance test data to conduct effective reviews
of CAA sections 112 and 129 standards, as well as for many other
purposes including compliance determinations, emission factor
development, and annual emission rate determinations. We believe that
improvements in the process of submitting, reviewing and storing test
data would result in increases in efficiency and cost savings to the
regulated community; state, local and tribal agencies; the public and
ourselves. These improvements are possible because stack testing firms
are increasingly collecting performance test data in electronic format,
making it possible to move to an electronic data submittal system that
would increase the ease and efficiency of data submittal and improve
data accessibility.
Through this proposal, the EPA is proposing a step to increase the
ease and efficiency of data submittal and improve data accessibility.
Specifically, the EPA is proposing that owners and operators of
Ferroalloys Production facilities submit electronic copies of required
performance test reports to the EPA's WebFIRE database. The WebFIRE
database was constructed to store performance test data for use in
developing emission factors. A description of the WebFIRE database is
available at http://cfpub.epa.gov/oarweb/index.cfm?action=fire.main.
As proposed above, data entry would be through an electronic
emissions test report structure called the Electronic Reporting Tool
(ERT). The ERT would be able to transmit the electronic report through
the EPA's Central Data Exchange network for storage in the WebFIRE
database, making submittal of data very straightforward and easy. A
description of the ERT can be found at http://www.epa.gov/ttn/chief/ert/index.html.
The proposal to submit performance test data electronically to the
EPA would apply only to those performance tests conducted using test
methods that will be supported by the ERT. The ERT contains a specific
electronic data entry form for most of the commonly used EPA reference
methods. A listing of the pollutants and test methods supported by the
ERT is available at http://www.epa.gov/ttn/chief/ert/index.html. We
believe that industry would benefit from this proposed approach to
electronic data submittal. Having these data, the EPA would be able to
develop improved emission factors, make fewer information requests, and
promulgate better regulations.
One major advantage of the proposed submittal of performance test
data through the ERT is a standardized method to compile and store much
of the documentation required to be reported by this rule. Another
advantage is that the ERT clearly states what testing information would
be required. Another important proposed benefit of submitting these
data to the EPA at the time the source test is conducted is that it
should substantially reduce the effort involved in data collection
activities in the future. When the EPA has performance test data in
hand, there will likely be fewer or less substantial data collection
requests in conjunction with prospective required residual risk
assessments or technology reviews. This would result in a reduced
burden on both affected facilities (in terms of reduced manpower to
respond to data collection requests) and the EPA (in terms of preparing
and distributing data collection requests and assessing the results).
State, local, and tribal agencies could also benefit from more
streamlined and accurate review of electronic data submitted to them.
The ERT would allow for an electronic review process rather than a
manual data assessment making review and evaluation of the source
provided data and calculations easier and more efficient. Finally,
another benefit of the proposed data submittal to WebFIRE
electronically is that these data would greatly improve the overall
quality of existing and new emissions factors by supplementing the pool
of emissions test data for establishing emissions factors and by
ensuring that the factors are more representative of current industry
operational procedures. A common complaint heard from industry and
regulators is that emission factors are outdated or not representative
of a particular source category. With timely receipt and incorporation
of data from most performance tests, the EPA would be able to ensure
that emission factors, when updated, represent the most current range
of operational practices. In summary, in addition to supporting
regulation development, control strategy development, and other air
pollution control activities, having an electronic database populated
with performance test data would save industry, state, local, tribal
agencies, and the EPA significant time, money, and effort while also
improving the quality of emission inventories and, as a result, air
quality regulations.
3. Emissions Averaging
We are proposing to add an emissions averaging option for electric
arc furnace stack emissions (PM, mercury, PAH, HCl or formaldehyde). If
you have more than one existing emission source (e.g., electric arc
furnace) located at one or more contiguous properties, which are under
common control of the same person (or persons under common control),
you may demonstrate compliance by emission averaging among the existing
emission sources, if your averaged emissions for such emission sources
are equal to or less than the applicable emission limit.
We are also proposing to allow averaging between existing process
fugitive control devices for PM stack emissions as a second averaging
group. However, we believe it may be appropriate to combine these
process fugitive stack emissions into the furnace stack averaging group
for PM emissions
[[Page 72537]]
for two reasons. First, both types of emissions are likely to be
controlled with similar, if not common control devices, e.g., large
fabric filters. Second, we are proposing to apply an identical PM
emission limit for both of these emission sources, which would simplify
averaging of PM emissions. We request comment on this option.
We are also proposing to allow averaging between existing crushing
and screening equipment for PM stack emissions. We believe this is a
distinct averaging group compared to the furnace and process fugitives
groups. The airflow and associated control devices are typically much
smaller and they are subject to a more stringent emission limit than
the other PM sources. However, we request comment on the potential for
more broadly defined averaging options for this group.
As part of the EPA's general policy of encouraging the use of
flexible compliance approaches where they can be properly monitored and
enforced, we are including emissions averaging for existing sources in
this proposed rule. Emissions averaging can provide sources the
flexibility to comply in the least costly manner while still
maintaining regulation that is workable and enforceable. Emissions
averaging would allow owners and operators of an existing affected
source to demonstrate that the source complies with the proposed
emission limits by averaging the emissions from an individual affected
emission unit that is emitting above the proposed emission limits with
other affected emission units at the same facility that are emitting
below the proposed emission limits and that are within the same
averaging group, as described below.
This proposed rule includes an emissions averaging compliance
alternative because emissions averaging represents an equivalent, more
flexible, and less costly alternative to controlling certain emission
points to MACT levels. We have concluded that a limited form of
averaging could be implemented that would not lessen the stringency of
the MACT limits and would provide flexibility in compliance, cost and
energy savings to owners and operators of existing sources. We also
recognize that we must ensure that any emissions averaging option can
be implemented and enforced, will be clear to sources, and most
importantly, will be no less stringent than unit by unit implementation
of the MACT limits.
The EPA is proposing to establish within a NESHAP a unified
compliance regimen that permits averaging within an existing affected
source across individual affected units subject to the standard under
certain conditions. Averaging across affected units is permitted only
if it can be demonstrated that the total quantity of any regulated
pollutant that may be emitted by that portion of a contiguous major
source that is subject to the NESHAP will not be greater under the
averaging mechanism than it could be if each individual affected unit
complied separately with the applicable standard. Under this test, the
practical outcome of averaging is equivalent to compliance with the
MACT limits by each discrete unit, and the statutory requirement that
the MACT standard reflect the maximum achievable emissions reductions
is, therefore, fully effectuated.
In past rulemakings, the EPA has generally imposed certain limits
on the scope and nature of emissions averaging programs. These limits
include: (1) No averaging between different types of pollutants; (2) no
averaging between sources that are not part of the same affected
source; (3) no averaging between individual sources within a single
major source if the individual sources are not subject to the same
NESHAP; and (4) no averaging between existing sources and new sources.
This proposed rule is consistent with these limitations. First,
emissions averaging would only be permitted between individual sources
at a single existing affected source, and would only be permitted
between individual sources subject to the proposed Ferroalloys
Production NESHAP. Further, emissions averaging would not be permitted
between two or more different affected sources. Finally, new affected
sources could not use emissions averaging. Accordingly, we have
concluded that the averaging of emissions across affected units is
consistent with the CAA.
In addition, this proposed rule would require each facility that
intends to utilize emission averaging to submit an emission averaging
plan, which provides additional assurance that the necessary criteria
will be met. In this emission averaging plan, the facility must include
the identification of: (1) All units in the averaging group; (2) the
control technology installed; (3) the process parameters that will be
monitored; (4) the specific control technology or pollution prevention
measure(s) to be used; (5) the test plan for the measurement of the HAP
being averaged; and (6) the operating parameters to be monitored for
each control device. Upon receipt, the regulatory authority would not
be able to approve an emission averaging plan containing averaging
between emissions of different types of pollutants or between different
affected sources (e.g., between furnaces and crushing and screening
equipment).
We seek comment on use of a discount factor when emissions
averaging is used and on the appropriate value of a discount factor, if
used. Such discount factors (e.g., 10 percent) have been used in
previous NESHAP, particularly where there was variation in the types of
units within a common source category to ensure that the environmental
benefit was being achieved. In this situation, however, the affected
sources are more homogeneous, making emissions averaging a more
straight forward analysis. Further, with the monitoring and compliance
provisions that are being proposed, there is additional assurance that
the environmental benefit will be realized. The emissions averaging
provisions in this proposed rule are based in part on the emissions
averaging provisions in the Hazardous Organic NESHAP (HON). The legal
basis and rationale for the HON emissions averaging provisions were
provided in the preamble to the final HON.\36\
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\36\ Hazardous Organic NESHAP (59 FR 19425; April 22, 1994).
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4. Other Changes
The following lists additional minor changes to the NESHAP we are
proposing. The main focus of these changes is to ensure that the rule
provides adequate monitoring, reporting, recordkeeping and testing
provisions to ensure that the affected sources are able to demonstrate
continuous compliance with the proposed standards. These changes
reflect changes we have made to many other existing NESHAP to improve
the quality of these compliance requirements. This list also includes
proposed rule changes that address editorial corrections and plain
language revisions:
Reduce frequency of emission testing for the primary
furnace control devices for PM and propose periodic testing for PM
and other regulated pollutants. This change is possible because of
requirement to conduct continuous monitoring. Also add a periodic
testing requirement for the building ventilation system control
devices and crushing and screening equipment control devices.
Add requirement for new and existing baghouses that
control furnace or building ventilation systems to be equipped with
BLDS to demonstrate continuous compliance. Retain provisions for
baghouses to have a baghouse SOP manual.
Add requirements to implement and enforce more detailed
requirements for
[[Page 72538]]
continuous parameter monitoring systems to ensure continuous
compliance.
Reduce the shop building opacity limit to 10 percent
opacity to reflect current industry performance. Eliminate 6-minute
excursion level because it does not provide any significant
flexibility (sources that tend to exceed the general opacity limit
in any 6-minute period tend to do so for several minutes so that the
excursions for one 6-minute period is meaningless). Eliminate events
excluded from the opacity observation as they are infrequent, can be
avoided in some cases, are emitted from operations we intend to
control better, and can be confusing to enforce.
Change the format of the PM standards to reflect an
outlet concentration format (mg/dscm). This format is the direct
output of the emissions test and reflects the constant output nature
of the predominant control device, i.e., a baghouse.
Add PM continuous emissions monitoring system as an
alternative to installing and operating a BLDS.
Editorial changes, including revising the titles of
sections in the subpart to better reflect the description of
proposed requirements and to make the regulation easier for the
reader to navigate.
Update the recordkeeping and reporting sections to
reflect the new monitoring requirements and monitoring options
described above.
Update the compliance dates to include the anticipated
dates the proposed requirements will become effective.
F. What compliance dates are we proposing?
We are proposing that facilities must comply with the new proposed
requirements in this action (which are being proposed under CAA
sections 112(d)(2), 112(d)(3), 112(d)(6) and 112(f)(2) for all affected
sources), no later than 2 years after the effective date of this rule.
In the period between the effective date of this rule and the
compliance date, existing sources would continue to comply with the
existing requirements specified in Sec. Sec. 63.1650 through 63.1661.
Under 40 CFR 63.6(i)(4)(ii), ``the owner or operator of an existing
source unable to comply with a relevant standard established * * *
pursuant to section 112(f) * * * may request that the Administrator
grant an extension allowing the source up to 2 years after the
standard's effective date to comply with the standard.'' The rule
further specifies a written application for such a request. Here, the
EPA is already fully aware of the steps needed for each source to
comply with the proposed standards and to reasonably estimate the
amount of time it will take each source to do so. We believe that the
2-year extension would be warranted in all cases for sources needing to
upgrade current practice. This includes the time needed to: Construct
required building ventilation systems and install associated control
devices for process fugitive sources; determine appropriate mercury and
PAH control devices, locations, amount and type of carbon needed and
assess potential waste disposal issues; select and install appropriate
monitoring technologies; seek bids, select a vendor, install and test
the new equipment; and, purchase, install and conduct QA and quality
control measures on compliance monitoring equipment (see Estimated Time
Needed to Achieve Compliance with The Proposed Revisions to the MACT
standard for Ferroalloys Production Facilities, which is available in
the docket for this proposed action). The EPA believes it reasonable to
interpret 40 CFR 63.6(i)(4)(ii) to allow this plenary finding, rather
than utilizing a facility-by-facility application process, when the
facts are already known and a category-wide adjudication is therefore
possible. In addition, utilizing this process allows for public comment
on the issue which would not be possible if a case-by-case application
process with a 90-day window for completion were used.
V. Summary of Cost, Environmental, and Economic Impacts
A. What are the affected sources?
We anticipate that the two manganese production ferroalloys
production facilities currently operating in the United States will be
affected by these proposed amendments. We do not know of any new
facilities that are expected to be constructed in the foreseeable
future. However, there is one facility that has a permit to produce
ferromanganese or silicomanganese in an electric arc furnace, but it
did so for only a brief period, several years ago. It is possible that
this facility could resume production or another non-manganese
ferroalloy producer could decide to commence production of
ferromanganese or silicomanganese. One of the existing facilities is
considering building a new manganese furnace, but their timeline and
actual intent to go forward is unclear. Given this uncertainty, our
impact analysis is focused on the two existing sources that are
currently operating.
B. What are the air quality impacts?
The EPA estimated the emissions reductions that are expected to
result from the proposed amendments to the 1999 NESHAP compared to the
2010 baseline emissions estimates. A detailed documentation of the
analysis can be found in: Draft Cost Impacts of the Revised NESHAP for
the Ferroalloys Production Source Category.
Emissions of metal HAP from ferroalloys production sources have
declined in recent years, primarily as the result of state actions and
also due to the industry's own initiative. The current proposal would
cut HAP emissions (primarily particulate metal HAP such as manganese,
arsenic and nickel) by 60 percent from their current levels. Under the
proposed emissions limit for process fugitives emissions from the
furnace building, we estimate that the HAP emissions reductions would
be 81 tpy, including significant reductions of manganese. We also
anticipate mercury reductions of 420 lb/yr and PAH reductions of 2.5
tpy from installation of activated carbon injection controls at one
facility. Total HAP reductions for the two facilities are estimated to
be 84 tpy.
Based on the emissions data available to the EPA, we believe that
both facilities will be able to comply with the proposed emissions
limits for HCl and formaldehyde without additional controls. There may
be some formaldehyde emission reductions at the facility that we
believe will be required to install an activated carbon injection
system, but we have not quantified these reductions because of the
uncertainty of the effectiveness of the activated carbon system
designed for mercury and PAH removal compared to formaldehyde removal.
We do not anticipate any reductions in HCl.
C. What are the cost impacts?
Under the proposed amendments, ferroalloys production facilities
are expected to incur capital costs for the installation of ductwork
and baghouses for building ventilation and activated carbon injection
systems. There would also be capital costs associated with installing
new or improved continuous monitoring systems, included installation of
BLDS on the furnace and building ventilation baghouses that are not
currently equipped with these systems.
The capital costs for each facility were estimated based on the
number and types of upgrades required. The memorandum Draft Cost
Impacts of the Revised NESHAP for the Ferroalloys Production Source
Category includes a complete description of the cost estimate methods
used for this analysis and is available in the docket.
The majority of the capital costs estimated for compliance with the
amendments proposed in this action are for purchasing new control
devices. For the shop building ventilation system, we assumed that each
facility would
[[Page 72539]]
need to install a building ventilation system in order to comply with
the proposed shop building emissions limits. For each facility, we
estimated the square footage of shop building air that would need to be
evacuated and the size of control device that would be required.
Although the proposed amendments would provide the alternative option
to install monitors at or near the property boundary to demonstrate
compliance with the building ventilation requirements, we assume that
sources would be unlikely to meet the alternative standard without
improving the level of control in the shop building.
To estimate the cost for the building ventilation fabric filter, we
contacted a vendor who had recently supplied a fabric filter to one of
the facilities to obtain assistance in developing a cost estimate for
the installation. The equipment-only cost supplied by the vendor was
used in conjunction with techniques described in the sixth edition of
the EPA Air Pollution Control Cost Manual \37\ to estimate total
installed capital cost and annual costs.
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\37\ http://epa.gov/ttn/catc/products.html#cccinfo.
---------------------------------------------------------------------------
Our cost model included installation of the baghouse and any
necessary fans, ductwork, and site work, including extra ductwork for
connection to the building roof monitors. The total installed capital
cost of three fabric filters (two at one facility, one at the second
facility) designed for a flow-rate of 150,000 actual cubic feet per
minute was estimated at $9.4 million. The annualized capital cost and
operational and maintenance costs are estimated at $2.3 million, via
techniques described in the sixth edition of the EPA Air Pollution
Control Cost Manual. The annualized cost assumes a 20-year life
expectancy for the unit and, to be consistent with OMB Guidance in
Circular A-4, a 7 percent cost of capital as an estimate of the
annualized capital cost.
We considered installation of both fixed carbon beds and activated
carbon injections for the control of mercury and PAH emissions. After
talking to carbon vendors, we learned that fixed carbon beds are not a
viable option given the size of the furnace airstream we would need to
control. We also considered whether to put the activated carbon
injection upstream or downstream of the existing PM control device. By
installing the system downstream of the PM control device, we would
avoid potential concerns with the activated carbon interfering with
potential sale or reuse of baghouse dust or potential increase in
mercury load in the scrubber sludge impoundment. This approach requires
installation of a separate ``polishing'' baghouse to capture the
injected carbon for disposal.
Unlike activated carbon systems used primarily for control of
volatile organic compounds, we have been told that mercury impregnated
compounds cannot be recycled. There is concern that such downstream
control could result in sufficient concentration of mercury in the
baghouse dust that the facility would be required to treat such dust as
a hazardous waste under the RCRA. However, based on conversations with
vendors and other mercury control experts, we believe that the
resulting waste will most likely be nonhazardous. We are seeking
comments on the cost methodology and assumptions used to develop these
cost estimates.
Costs for Activated Carbon Injection (ACI) were estimated using
cost equations developed for the Utility NESHAP.\38\ The calculated
equipment costs for ACI and fabric filters were used in conjunction
with techniques described in the sixth edition of the EPA Air Pollution
Control Cost Manual to estimate total installed capital cost and annual
costs. Our cost model included installation of the two ACI systems, one
polishing fabric filter, and associated fans, ductwork, and site work.
We estimate the total capital costs are $1.7 million and the annual
costs are $1.4 million.
---------------------------------------------------------------------------
\38\ Sargent & Lundy, IPM Model--Revisions to Cost and
Performance for APC Technologies, Mercury Control Cost Development
Methodology Final, March, 2011. http://www.epa.gov/airmarkt/progsregs/epa-ipm/docs/append5_3.pdf.
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The estimated costs for the proposed change to the monitoring
requirements for baghouses, including installation of seven new BLDS
for four existing furnace baghouses and three building ventilation
baghouses is $270,000 of capital cost. The capital cost for a
differential pressure monitor to ensure that shop buildings are under
negative pressure is $9,200. The capital cost estimated for a
continuous parameter monitoring system for the wet scrubber at one
facility is estimated to be $50,000. Finally, the estimated capital
cost for carbon injection monitoring is $20,000. The capital costs for
all additional monitoring and recordkeeping requirements, including the
baghouse monitoring proposed, is estimated at $340,200.
Annualized costs are estimated to be $94,000 for the BLDS, $18,000
for the scrubber parameter monitoring system, and $6,200 for the carbon
injection monitoring system. There is also an estimated annualized cost
to monitor the manganese ore content for mercury emissions of $1,200.
The estimated annual cost for reporting and recordkeeping is $37,000.
We estimate the costs of the periodic performance testing requirements
to be $800,000. The resulting total annualized costs are $347,000.
The total annualized costs for the proposed rule are estimated at
$4.0 million (2010 dollars). Table 6 provides a summary of the
estimated costs and emissions reductions associated with the proposed
amendments to the Ferroalloys Production NESHAP presented in today's
action.
Table 6--Estimated Costs and Reductions for the Proposed Standards in This Action
----------------------------------------------------------------------------------------------------------------
Estimated Estimated Total HAP Cost effectiveness in $ per
Proposed amendment capital cost annual cost emissions ton total HAP reduction
($MM) \1\ ($MM) reductions (tpy) (and in $ per pound)
----------------------------------------------------------------------------------------------------------------
Capture and Control Process 9.4 2.3 81 (of metal HAP) $0.03 MM per ton.
Fugitives. ($14 per pound).
MACT Limits for Mercury........ 1.7 1.4 0.2 (of mercury). $6.7 MM per ton.
($3,300 per pound).
MACT Limits for co-control of NA N/A 2.5 (of PAH)..... N/A.
PAH.
HCl and formaldehyde 0 0 0................ N/A.
concentration limits.
Compliance testing over 3-year N/A 0.26 N/A.............. N/A.
period.
Annual average monitoring over 0.11 0.08 N/A.............. N/A.
3-year period.
----------------------------------------------------------------------------------------------------------------
[[Page 72540]]
D. What are the economic impacts?
We estimate that there will be no more than a 0.2 percent price
change and a similar reduction in output associated with the proposal.
The impacts to affected firms will be low because the annual compliance
costs are quite small when compared to the annual revenues for the two
affected parent firms (much less than 1 percent for each). The impacts
to affected consumers should also be quite small. Thus, there will not
be any significant impacts on affected firms and their consumers as a
result of this proposal.
E. What are the benefits?
We estimate the monetized benefits of this regulatory action to be
$71 million to $170 million (2010$), at a 3 percent discount rate in
the implementation year (2015). The monetized benefits of the
regulatory action at a 7 percent discount rate are $63 million to $160
million (2010$) in the same implementation year. Using alternate
relationships between PM2.5 and premature mortality supplied
by experts, higher and lower benefits estimates are plausible, but most
of the expert-based estimates fall between these two estimates.\39\ A
summary of the monetized benefits estimates at discount rates of 3
percent and 7 percent is in Table 7 of this preamble.
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\39\ Roman, et al., 2008. Expert Judgment Assessment of the
Mortality Impact of Changes in Ambient Fine Particulate Matter in
the U.S. Environ. Sci. Technol., 42, 7, 2268-2274.
Table 7--Summary of the Monetized Benefits Estimates for the Ferroalloys Industry in 2015
[Millions of 2010$]
----------------------------------------------------------------------------------------------------------------
Estimated
emission Total monetized Total monetized benefits (7% discount
Pollutant reductions benefits (3% rate)
(tpy) discount rate)
----------------------------------------------------------------------------------------------------------------
PM2.5.............................. 257 $71 to $170.......... $63 to $160.
----------------------------------------------------------------------------------------------------------------
\1\All estimates are for the implementation year (``2015'', assuming the final rule is published in January
2012) and are rounded to two significant figures so numbers may not sum across rows. All fine particles are
assumed to have equivalent health effects. Benefits from reducing HAPs emissions are not included.
These benefits estimates represent the total monetized human health
benefits for populations exposed to less PM2.5 in 2015 from
controls installed to reduce air pollutants in order to meet these
proposed standards. These estimates are calculated as the sum of the
monetized value of avoided premature mortality from reducing
PM2.5. To estimate human health benefits derived from
reducing PM2.5, we used the general approach and methodology
laid out in Fann, Fulcher, and Hubbell (2009).\40\ However, in this
proposal we utilized source apportionment air quality modeling for the
ferroalloys industry.\41\ Therefore all benefits per ton estimates are
specific to the ferroalloys sector.
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\40\ Fann, N., C.M. Fulcher, B.J. Hubbell. 2009. ``The influence
of location, source, and emission type in estimates of the human
health benefits of reducing a ton of air pollution.'' Air Qual Atmos
Health (2009) 2:169-176.
\41\ U.S. Environmental Protection Agency. 2011. Technical
support document: Estimating the benefit per ton of reducing PM2.5
precursors from the ferroalloy sector (Draft); EPA: Research
Triangle Park, NC.
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To generate the BPT estimates, we used a model to convert emissions
of direct PM2.5 into changes in ambient PM2.5
levels and another model to estimate the changes in human health
associated with that change in air quality. Finally, the monetized
health benefits were divided by the emission reductions to create the
BPT estimates. These models assume that all fine particles, regardless
of their chemical composition, are equally potent in causing premature
mortality because there is no clear scientific evidence that would
support the development of differential effects estimates by particle
type. In this rule only directly emitted PM2.5 is
considered. Direct PM2.5 emissions convert directly into
ambient PM2.5; thus, to the extent that emissions occur in
population areas, exposures to direct PM2.5 will tend to be
higher than exposure to any other precursor, and monetized health
benefits will be higher as well.
For context, it is important to note that the magnitude of the PM
benefits is largely driven by the concentration response function for
premature mortality. Experts have advised the EPA to consider a variety
of assumptions, including estimates based on both empirical
(epidemiological) studies and judgments elicited from scientific
experts, to characterize the uncertainty in the relationship between
PM2.5 concentrations and premature mortality. For this rule,
we cite two key empirical studies, the American Cancer Society cohort
study \42\ and the extended Six Cities cohort study.\43\ In the
Regulatory Impact Analysis (RIA) \44\ for this rule, we also include
benefits estimates derived from expert judgments and other assumptions.
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\42\ Pope et al, 2002. ``Lung Cancer, Cardiopulmonary Mortality,
and Long-term Exposure to Fine Particulate Air Pollution.'' Journal
of the American Medical Association. 287:1132-1141.
\43\ Laden et al, 2006. ``Reduction in Fine Particulate Air
Pollution and Mortality.'' American Journal of Respiratory and
Critical Care Medicine. 173: 667-672.
\44\ U.S. Environmental Protection Agency, 2006. Final
Regulatory Impact Analysis: PM2.5 NAAQS. Prepared by
Office of Air and Radiation. October. Available on the Internet at
http://www.epa.gov/ttn/ecas/ria.html.
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The EPA strives to use the best available science to support our
benefits analyses. We recognize that interpretation of the science
regarding air pollution and health is dynamic and evolving. After
reviewing the scientific literature and recent scientific advice, we
have determined that the no-threshold model is the most appropriate
model for assessing the mortality benefits associated with reducing
PM2.5 exposure. Consistent with this recent advice, we are
replacing the previous threshold sensitivity analysis with a new
``Lowest Measured Level (LML)'' assessment. While an LML assessment
provides some insight into the level of uncertainty in the estimated PM
mortality benefits, the EPA does not view the LML as a threshold and
continues to quantify PM-related mortality impacts using a full range
of modeled air quality concentrations.
Most of the estimated PM-related benefits in this rule would accrue
to populations exposed to higher levels of PM2.5. Using the
Pope, et al., (2002) study, 89 percent of the population is exposed at
or above the LML of 7.5 [micro]g/m\3\. Using the Laden, et al., (2006)
study, 31 percent of the population is exposed above the LML of 10
[micro]g/m\3\. It is important to emphasize that we have high
confidence in PM2.5-related effects down to the lowest LML
of the major cohort studies. This fact is important,
[[Page 72541]]
because as we estimate PM-related mortality among populations exposed
to levels of PM2.5 that are successively lower, our
confidence in the results diminishes. However, our analysis shows that
the great majority of the impacts occur at higher exposures.
This analysis does not include the type of detailed uncertainty
assessment found in the 2006 p.m.2.5 NAAQS RIA because we lack the
necessary air quality input and monitoring data to run the benefits
model. In addition, we have not conducted any air quality modeling for
this rule. However, to estimate BPT specifically for this sector we did
have some updated air quality modeling. The 2006 PM2.5 NAAQS
benefits analysis provides an indication of the sensitivity of our
results to various assumptions.
It should be emphasized that the monetized benefits estimates
provided above do not include benefits from several important benefit
categories, including reducing other air pollutants, ecosystem effects,
and visibility impairment, as well as mercury and other HAPs. Although
we do not have sufficient information or modeling available to provide
monetized estimates for this rulemaking, we include a qualitative
assessment of the health effects of these other effects in the RIA \45\
for this proposed rule.
---------------------------------------------------------------------------
\45\ U.S. Environmental Protection Agency. Draft Regulatory
Impact Analysis (RIA) for the Proposed Manganese Ferroalloys RTR.
September 2011
---------------------------------------------------------------------------
F. What demographic groups might benefit the most from this regulation?
To examine the potential for any environmental justice (EJ) issues
that might be associated with the source category, we performed a
demographic analysis of the at-risk population. In this analysis, we
evaluated the distributions of HAP-related cancer and noncancer risks
from the Ferroalloys Production source category across different
social, demographic and economic groups within the populations living
near these two facilities. The methodology and the results of the
demographic analyses are included in a technical report, Risk and
Technology Review--Analysis of Socio-Economic Factors for Populations
Living Near Ferroalloys Facilities, available in the docket for this
action.
The results of the demographic analysis are summarized in Table 8
below. These results, for various demographic groups, are based on the
estimated risks from actual emissions levels for the population living
within 50 km of the facilities.
TABLE 8--Ferroalloy Production Demographic Risk Analysis Results
----------------------------------------------------------------------------------------------------------------
Population with
cancer risk at or Population with
Nationwide above 1-in-1 chronic hazard
million index above 1
----------------------------------------------------------------------------------------------------------------
Total Population.................................... 285,000,000 26,000 28,000
----------------------------------------------------------------------------------------------------------------
Race by Percent
----------------------------------------------------------------------------------------------------------------
White............................................... 75 97 97
All Other Races..................................... 25 3 3
----------------------------------------------------------------------------------------------------------------
Race by Percent
----------------------------------------------------------------------------------------------------------------
White............................................... 75 97 97
African American.................................... 12 1 0.8
Native American..................................... 0.9 0.3 0.3
Other and Multiracial............................... 12 2 1.8
----------------------------------------------------------------------------------------------------------------
Ethnicity by Percent
----------------------------------------------------------------------------------------------------------------
Hispanic............................................ 14 1 0.7
Non-Hispanic........................................ 86 99 99
----------------------------------------------------------------------------------------------------------------
Income by Percent
----------------------------------------------------------------------------------------------------------------
Below Poverty Level................................. 13 13 13
Above Poverty Level................................. 87 87 87
----------------------------------------------------------------------------------------------------------------
Education by Percent
----------------------------------------------------------------------------------------------------------------
Over 25 and without High School Diploma............. 13 11 9
Over 25 and with a High School Diploma.............. 87 89 91
----------------------------------------------------------------------------------------------------------------
The results of the Ferroalloy Production source category
demographic analysis indicate that there are approximately 26,000
people exposed to a cancer risk at or above one in one million and
approximately 28,000 people exposed to a chronic noncancer TOSHI
greater than 1 due to emissions from the source category (we note that
many of those in the first risk group are the same as those in the
second). The percentages of the at-risk population in each demographic
group (except for White and non-Hispanic) are similar to or lower than
their respective nationwide percentages. Implementation of the
provisions included in this proposal is expected to significantly
reduce the number of at-risk people due to HAP emissions from these
sources (from 26,000 people to about 1,000 for cancer risks and from
28,000 people to less than 10 for chronic noncancer TOSHI).
VI. Request for Comments
We are soliciting comments on all aspects of this proposed action.
In addition to general comments on this proposed action, we are also
interested
[[Page 72542]]
in any additional data that may help to reduce the uncertainties
inherent in the risk assessment and other analyses. We are specifically
interested in receiving corrections to the site-specific emissions
profiles 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. Section VII
of this preamble provides more information on submitting data.
VII. Submitting Data Corrections
The site-specific emissions profiles used in the source category
risk 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 facilities included in the source category.
If you believe that 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.
Emissions Calculation Method Code For Code description of the method
Revised Emissions. used to derive emissions. For
example, CEM, material
balance, stack test, etc.
Emissions Process Group................ Enter the general type of
emissions process associated
with the specified emissions
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 Emissions Release Point Type... Enter revised Emissions Release
Point 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 Identifier... Enter revised Facility Registry
Identifier here, which is an
ID assigned by the EPA
Facility Registry System.
REVISED HAP Emissions Performance Level Enter revised HAP Emissions
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).
Stack Comment.......................... Enter general comments about
emissions 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.
------------------------------------------------------------------------
[[Page 72543]]
2. Fill in the commenter information fields for each suggested
revision (i.e., commenter name, commenter organization, commenter email
address, commenter phone number, and revision comments).
3. Gather documentation for any suggested emissions revisions
(e.g., performance test reports, material balance calculations).
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-2010-0895 (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 RTR@epa.gov 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 RTR Web page at: http://www.epa.gov/ttn/atw/rrisk/rtrpg.html.
VIII. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review
Under Section 3(f)(1) of Executive Order 12866 (58 FR 51735,
October 4, 1993), this action is an ``economically significant
regulatory action'' because it is likely to have an annual effect on
the economy of $100 million or more. Accordingly, the EPA submitted
this action to OMB for review under Executive Orders 12866 and 13563
(76 FR 3821, January 21, 2011), and any changes made in response to OMB
recommendations have been documented in the docket for this action.
In addition, the EPA prepared an analysis of the potential costs
and benefits associated with this action. This analysis is contained in
the RIA for this proposed rule. A copy of the analysis is available in
the docket for this action, and the analysis is briefly summarized
above.
The cost and benefit analyses are subject to uncertainties. More
information on these uncertainties can be found in the RIA and in the
cost memo for the proposal.
A summary of the monetized benefits and net benefits for the
proposed rule at discount rates of 3 percent and 7 percent is in Table
2 of this preamble and a more detailed discussion of the benefits is
found in section V.E of this preamble.
For more information on the benefits analysis, please refer to the
RIA for this rulemaking, which is available in the docket.
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 the EPA has
been assigned EPA ICR number 2448.01. The information collection
requirements are not enforceable until OMB approves them. The
information requirements are based on notification, recordkeeping, and
reporting requirements in the NESHAP General Provisions (40 CFR part
63, subpart A), which are mandatory for all operators subject to
national emissions standards. These recordkeeping and reporting
requirements are specifically authorized by CAA section 114 (42 U.S.C.
7414). All information submitted to the EPA pursuant to the
recordkeeping and reporting requirements for which a claim of
confidentiality is made is safeguarded according to Agency policies set
forth in 40 CFR part 2, subpart B.
We are proposing new paperwork requirements to the Ferroalloys
Production source category in the form of increased frequency and
number of pollutants tested for stack testing as described in Sec.
63.1625(c) and tighter parameter monitoring requirements to demonstrate
continuous compliance as described in Sec. 63.1625(c)(6) and Sec.
63.1626. In conjunction shop building process fugitives monitoring, we
believe that sources are currently equipped with adequate monitoring
equipment and that the facilities will not incur a capital cost due to
this requirement.
For this proposed rule, the EPA is adding affirmative defense to
the estimate of burden in the ICR. To provide the public with an
estimate of the relative magnitude of the burden associated with an
assertion of the affirmative defense position adopted by a source, the
EPA has provided administrative adjustments to this ICR to show what
the notification, recordkeeping and reporting requirements associated
with the assertion of the affirmative defense might entail. The EPA's
estimate for the required notification, reports and records for any
individual incident, including the root cause analysis, totals $3,141
and is based on the time and effort required of a source to review
relevant data, interview plant employees, and document the events
surrounding a malfunction that has caused an exceedance of an emissions
limit. The estimate also includes time to produce and retain the record
and reports for submission to the EPA. The EPA provides this
illustrative estimate of this burden because these costs are only
incurred if there has been a violation and a source chooses to take
advantage of the affirmative defense.
Given the variety of circumstances under which malfunctions could
occur, as well as differences among sources' operation and maintenance
practices, we cannot reliably predict the severity and frequency of
malfunction-related excess emissions events for a particular source. It
is important to note that the EPA has no basis currently for estimating
the number of malfunctions that would qualify for an affirmative
defense. Current historical records would be an inappropriate basis, as
source owners or operators previously operated their facilities in
recognition that they were exempt from the requirement to comply with
emissions standards during malfunctions. Of the number of excess
emissions events reported by source operators, only a small number
would be expected to result from a malfunction (based on the definition
above), and only a subset of excess emissions caused by malfunctions
would result in the source choosing to assert the affirmative defense.
Thus, we believe the number of instances in which source operators
might be expected to avail themselves of the affirmative defense will
be extremely small. For this reason, we estimate no more than 1 or 2
such occurrences for all sources subject to subpart XXX over the 3-year
period covered by this ICR. We expect to gather information on such
events in the future and will revise this estimate as better
information becomes available.
We estimate two regulated entities are currently subject to subpart
XXX and will be subject to all proposed standards. The annual
monitoring, reporting, and recordkeeping burden for this collection
(averaged over the first 3 years after the effective date of the
standards) for these amendments to subpart XXX (Ferroalloys Production)
is estimated to be $384,000 per year. This includes 483 labor hours per
year at a total labor cost of $37,000 per year, and total non-labor
capital and operation and maintenance costs of $347,000 per year. This
estimate includes performance tests, notifications,
[[Page 72544]]
reporting, and recordkeeping associated with the new requirements for
front-end process vents and back-end process operations. The total
burden for the Federal government (averaged over the first 3 years
after the effective date of the standard) is estimated to be 48 hours
per year at a total labor cost of $2,200 per year. Burden is defined at
35 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 the
EPA's regulations in 40 CFR are listed in 40 CFR part 9. When these
ICRs are approved by OMB, the Agency will publish a technical amendment
to 40 CFR part 9 in the Federal Register to display the OMB control
numbers for the approved information collection requirements contained
in the final rules.
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, the EPA has established a public docket
for this rule, which includes this ICR, under Docket ID number EPA-HQ-
OAR-2010-0895. Submit any comments related to the ICR to the EPA and
OMB. See the ADDRESSES section at the beginning of this notice for
where to submit comments to the 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. Because OMB is required to make a decision concerning the ICR
between 30 and 60 days after November 23, 2011, a comment to OMB is
best assured of having its full effect if OMB receives it by December
23, 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 this proposed rule on
small entities, small entity is defined as: (1) A small business as
defined by the Small Business Administration's (SBA) regulations at 13
CFR 121.201; (2) a small governmental jurisdiction that is a government
of a city, county, town, school district or special district with a
population of less than 50,000; and (3) a small organization that is
any not-for-profit enterprise that is independently owned and operated
and is not dominant in its field. For this source category, which has
the NAICS code 331112 (i.e., Electrometallurgical ferroalloy product
manufacturing), the SBA small business size standard is 750 employees
according to the SBA small business standards definitions.
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. Neither of
the companies affected by this rule is considered to be a small entity
per the definition provided in this section.
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 proposed
rule 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 the EPA
policy to promote communications between the EPA and state and local
governments, the EPA specifically solicits comment on this proposed
rule from State and local officials.
F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments
This proposed rule does not have tribal implications, as specified
in Executive Order 13175 (65 FR 67249, November 9, 2000). Thus,
Executive Order 13175 does not apply to this action.
The 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 the Agency does not believe the
environmental health risks or safety risks addressed by this action
present a disproportionate risk to children. The report, Analysis of
Socio-Economic Factors for Populations Living Near Ferroalloys
Facilities, shows that, prior to the implementation of the provisions
included in this proposal, on a nationwide basis, there are
approximately 26,000 people exposed to a cancer risk at or above one in
one million and approximately 28,000 people exposed to a chronic
noncancer TOSHI greater than 1 due to emissions from the source
category. The percentages for all demographic groups, including
children 18 years and younger, are similar to or lower than their
respective nationwide percentages. Further, implementation of the
provisions included in this proposal is expected to significantly
reduce the number of at-risk people due to HAP emissions from these
sources (from between 26,000 to 28,000 people to about 1,000),
providing significant benefit to all the demographic groups in the at-
risk population.
This proposed rule is expected to reduce environmental impacts for
everyone, including children. This action proposes emissions limits at
the levels based on MACT, as required by the CAA. Based on our
analysis, we believe that this rule does not have a disproportionate
impact on children.
The public is invited to submit comments or identify peer-reviewed
studies and data that assess effects of
[[Page 72545]]
early life exposure to manganese, lead, arsenic, nickel, or mercury.
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 and therefore no additional
costs for sources in the energy supply, distribution, or use sectors.
I. National Technology Transfer and Advancement Act (NTTAA)
Section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (NTTAA), Public Law No. 104-113, 12(d) (15 U.S.C. 272 note)
directs the EPA to use voluntary consensus standards (VCS) in its
regulatory activities, unless to do so would be inconsistent with
applicable law or otherwise impractical. VCS are technical standards
(e.g., materials specifications, test methods, sampling procedures, and
business practices) that are developed or adopted by VCS bodies. NTTAA
directs the EPA to provide Congress, through OMB, explanations when the
agency decides not to use available and applicable VCS.
This proposed rulemaking involves technical standards. The EPA
proposes to use EPA Methods 1, 2, 3A, 3B, 4, 5, 5D, 9, 10, 26A, 30B,
316, CARB 429, SW-846 Method 3052, SW-846 Method 7471b and EPA water
Method 1631E of 40 CFR Part 60, Appendix A. No applicable VCS were
identified for EPA Methods 30B, 5D, 316, 1631E and CARB 429, SW-846
Method 3052, and SW-846 Method 7471b.
Two VCS were identified acceptable alternatives to EPA test methods
for the purposes of this rule. The VCS standard ANSI/ASME PTC 19-10-
1981-Part 10, ``Flue and Exhaust Gas Analyses'' is an acceptable
alternative to Method 3B. The VCS ASTM D7520-09, ``Standard Test Method
for Determining the Opacity of a Plume in the Outdoor Ambient
Atmosphere'' is an acceptable alternative to Method 9 under specified
conditions. The Agency identified 18 VCS as being potentially
applicable to these methods cited in this rule. However, the EPA
determined that the 18 candidate VCS would not be practical due to lack
of equivalency, documentation, validation data and other important
technical and policy considerations. The 18 VCS and other information
and conclusions, including the search and review results, are in the
docket for this proposed rule. The EPA welcomes comments on this aspect
of this proposed rulemaking and, specifically, invites the public to
identify potentially-applicable voluntary consensus standards and to
explain why such standards should be used in this regulation.
Under section 63.7(f) and section 63.8(f) of Subpart A of the
General Provisions, a source may apply to the EPA for permission to use
alternative test methods or alternative monitoring requirements in
place of any required testing methods, performance specifications, or
procedures in the proposed rule.
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.
The EPA has proposed that the current health risks posed by
emissions from this source category are unacceptable. There are about
26,000 to 28,000 people nationwide that are currently subject to health
risks which may not be considered neglible (i.e., cancer risks greater
than one in one million or chronic noncancer TOSHI greater than 1) due
to emissions from this source category. The demographic makeup of this
``at-risk'' population is similar to the national distribution for all
demographic groups. The proposed rule will reduce the number of people
in this at-risk group from between 26,000-28,000 people to about 1,000
people. Based on this analysis, the EPA is proposing that the proposed
rule will not have disproportionately high and adverse human health or
environmental effects on minority or low-income populations because it
increases the level of environmental protection for all affected
populations.
List of Subjects in 40 CFR Part 63
Air pollution control, Environmental protection, Hazardous
substances, Incorporation by reference, Reporting and recordkeeping
requirements.
Dated: November 4, 2011.
Lisa P. Jackson,
Administrator.
For the reasons stated in the preamble, part 63 of title 40,
chapter I, of the Code of Federal Regulations is proposed to be amended
as follows:
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 63.14 is amended by:
a. Adding paragraph (b)(69);
b. Revising paragraph (i)(1);
c. Revising paragraph (p)(6) and adding paragraphs (p)(8) and
(p)(9); and
d. By adding paragraphs (r)(1) and (r)(2).
Sec. 63.14 Incorporations by reference.
(b) * * *
(69) ASTM D7520-09, ``Standard Test Method for Determining the
Opacity in a Plume in an Outdoor Ambient Atmosphere,'' IBR approved for
Sec. 63.1625(b)(9).
* * * * *
(i) * * *
(1) ANSI/ASME PTC 19.10-1981, ``Flue and Exhaust Gas Analyses [Part
10, Instruments and Apparatus],'' IBR approved for Sec. Sec.
63.309(k)(1)(iii), 63.865(b), 63.1625(b)(3)(iii), 63.3166(a)(3),
63.3360(e)(1)(iii), 63.3545(a)(3), 63.3555(a)(3), 63.4166(a)(3),
63.4362(a)(3), 63.4766(a)(3), 63.4965(a)(3), 63.5160(d)(1)(iii),
63.9307(c)(2), 63.9323(a)(3), 63.11148(e)(3)(iii), 63.11155(e)(3),
63.11162(f)(3)(iii) and (f)(4), 63.11163(g)(1)(iii) and (g)(2),
63.11410(j)(1)(iii), 63.11551(a)(2)(i)(C), table 5 to subpart DDDDD of
this part, table 1 to subpart ZZZZZ of this part, and table 4 to
subpart JJJJJJ of this part.
* * * * *
(p) * * *
(6) SW-846-7471B, Mercury in Solid Or Semisolid Waste (Manual Cold-
Vapor Technique), Revision 2, February 2007, in EPA Publication No. SW-
846, Test Methods for Evaluating Solid Waste, Physical/Chemical
Methods, Third Edition, IBR approved for Sec. 63.1625(b)(10), table 6
to subpart DDDDD of this part and table 5 to subpart JJJJJJ of this
part.
* * * * *
(8) SW-846-Method 3052, Microwave Assisted Acid Digestion Of
Siliceous
[[Page 72546]]
and Organically Based Matrices, Revision 0, December 1996, in EPA
Publication No. SW-846, Test Methods for Evaluating Solid Waste,
Physical/Chemical Methods, Third Edition, IBR approved for Sec.
63.1625(b)(10).
(9) Method 1631, Revision E: Mercury in Water by Oxidation, Purge
and Trap, and Cold Vapor Atomic Fluorescence Spectrometry, August 2002
located at: http://water.epa.gov/scitech/methods/cwa/metals/mercury/upload/2007_07_10_methods_;method--mercury--1631.pdf, IBR approved
for Sec. 63.1625(b)(10).
(r) The following material is available from the California Air
Resources Board (CARB), 1102 Q Street, Sacramento, California 95814,
(http://www.arb.ca.gov/testmeth/vol3/M_429.pdf).
(1) Method 429, Determination of Polycyclic Aromatic Hydrocarbon
(PAH) Emissions from Stationary Sources, Adopted September 1989,
Amended July 1997, IBR approved for Sec. 63.1625(b)(11).
(2) [Reserved]
* * * * *
Subpart XXX--[Amended]
3. Section 63.1620 is added to read as follows:
Sec. 63.1620 Am I subject to this subpart?
(a) You are subject to this subpart if you own or operate a new or
existing ferromanganese and/or silicomanganese production facility that
is a major source or is co-located at a major source of hazardous air
pollutant emissions.
(b) You are subject to this subpart if you own or operate any of
the following equipment as part of a ferromanganese or silicomanganese
production facility:
(1) Open, semi-sealed, or sealed submerged arc furnace,
(2) Casting operations,
(3) Metal oxygen refining (MOR) process,
(4) Crushing and screening operations,
(5) Outdoor fugitive dust sources.
(c) A new affected source is any of the sources listed in paragraph
(b) of this section for which construction or reconstruction commenced
after November 23, 2011.
(d) Table 1 of this subpart specifies the provisions of subpart A
of this part that apply to owners and operators of ferromanganese and
silicomanganese production facilities subject to this subpart.
(e) If you are subject to the provisions of this subpart, you are
also subject to title V permitting requirements under 40 CFR parts 70
or 71, as applicable.
(f) Emission standards in this subpart apply at all times.
4. Section 63.1621 is added to read as follows:
Sec. 63.1621 What are my compliance dates?
(a) Existing affected sources must be in compliance with the
provisions specified in Sec. Sec. 63.1620 through 63.1630 no later
than [2 YEARS AFTER EFFECTIVE DATE OF FINAL RULE].
(b) Affected sources in existence prior to November 23, 2011 must
be in compliance with the provisions specified in Sec. Sec. 63.1650
through 63.1661 by November 21, 2001 and until [2 YEARS AFTER EFFECTIVE
DATE OF FINAL RULE]. As of [2 YEARS AFTER EFFECTIVE DATE OF FINAL
RULE], the provisions of Sec. Sec. 63.1650 through 63.1661 cease to
apply to affected sources in existence prior to November 23, 2011. The
provisions of Sec. Sec. 63.1650 through 63.1661 remain enforceable at
a source for its activities prior to [2 YEARS AFTER EFFECTIVE DATE OF
FINAL RULE].
(c) If you own or operate a new affected source that commences
construction or reconstruction after November 23, 2011, you must comply
with the requirements of this subpart by [EFFECTIVE DATE OF FINAL
RULE], or upon startup of operations, whichever is later.
5. Section 63.1622 is added to read as follows:
Sec. 63.1622 What definitions apply to this subpart?
Terms in this subpart are defined in the Clean Air Act (Act), in
subpart A of this part, or in this section as follows:
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.
Bag leak detection system means a system that is capable of
continuously monitoring particulate matter (dust) loadings in the
exhaust of a baghouse in order to detect bag leaks and other upset
conditions. A bag leak detection system includes, but is not limited
to, an instrument that operates on triboelectric, light scattering,
light transmittance, or other effect to continuously monitor relative
particulate matter loadings.
Building ventilation means a system of ventilated ducts designed to
place the shop building under negative pressure and to capture process
fugitive emissions from the shop building.
Capture system means the collection of components used to capture
the gases and fumes released from one or more emissions points and then
convey the captured gas stream to a control device or to the
atmosphere. A capture system may include, but is not limited to, the
following components as applicable to a given capture system design:
duct intake devices, hoods, enclosures, ductwork, dampers, manifolds,
plenums, and fans.
Casting means the period of time from when molten ferroalloy is
removed from the tapping station until pouring into casting molds or
beds is completed. This includes the following operations: pouring
alloy from one ladle to another, slag separation, slag removal, and
ladle transfer by crane, truck, or other conveyance.
Crushing and screening equipment means the crushers, grinders,
mills, screens and conveying systems used to crush, size, and prepare
for packing manganese-containing materials, including raw materials,
intermediate products, and final products.
Electric arc furnace means any furnace where electrical energy is
converted to heat energy by transmission of current between electrodes
partially submerged in the furnace charge.
Ladle treatment means a post-tapping process including metal and
alloy additions where chemistry adjustments are made in the ladle after
furnace smelting to achieve a specified product.
Local ventilation means hoods and ductwork designed to capture
process fugitive emissions close to the area where the emissions are
generated (e.g., tap hoods).
Metal oxygen refining (MOR) process means the reduction of the
carbon content of ferromanganese through the use of oxygen.
Outdoor fugitive dust source means a stationary source from which
hazardous air pollutant-bearing particles are discharged to the
atmosphere due to wind or mechanical inducement such as vehicle
traffic. Fugitive dust sources include plant roadways, yard areas, and
outdoor material storage and transfer operations.
Plant roadway means any area at a ferromanganese and
silicomanganese production facility that is subject to plant mobile
equipment, such as fork lifts, front end loaders, or trucks, carrying
manganese-bearing materials. Excluded from this definition are employee
and visitor parking areas, provided they are not subject to traffic by
plant mobile equipment.
Primary emissions means gases and emissions collected by hoods and
ductwork located above an open furnace or under the cover of a semi-
closed or sealed furnace.
[[Page 72547]]
Process fugitive emissions source means a source of hazardous air
pollutant emissions that is associated with ferromanganese or
silicomanganese production, but is not the primary exhaust stream from
an electric arc furnace, MOR or crushing and screening equipment, and
is not a fugitive dust source. Process fugitive sources include
emissions that escape capture from the electric arc furnace, tapping
operations, casting operations, ladle treatment, MOR or crushing or
screening equipment.
Shop building means the building which houses one or more electric
arc furnaces.
Shutdown means the cessation of operation of an affected source for
any purpose.
Startup means the setting in operation of an affected source for
any purpose.
Tapping emissions means the gases and emissions associated with
removal of product from the electric arc furnace under normal operating
conditions, such as removal of metal under normal pressure and movement
by gravity down the spout into the ladle and filling the ladle.
Tapping period means the time from when a tap hole is opened until
the time a tap hole is closed.
6. Section 63.1623 is added to read as follows:
Sec. 63.1623 What are the emissions standards for new, reconstructed
and existing facilities?
(a) Electric arc furnaces. You must install, operate, and maintain
a capture system that collects the emissions from each electric arc
furnace (including charging, melting, and tapping operations and
emissions from any vent stacks) and conveys the collected emissions to
a control device for the removal of the pollutants specified in the
emissions standards specified in paragraphs (a)(1) through (a)(6) of
this section.
(1) Particulate matter emissions.
(i) You must not discharge exhaust gases (including primary and
tapping emissions) containing particulate matter in excess of 9.3
milligrams per dry standard cubic meter (mg/dscm), corrected to 2
percent carbon dioxide (CO2) into the atmosphere from any
new or reconstructed electric arc furnace. This emission limit must be
met by any furnace vent stacks.
(ii) You must not discharge exhaust gases (including primary and
tapping emissions) containing particulate matter in excess of 24 mg/
dscm, corrected to 2 percent CO2 into the atmosphere from
any existing electric arc furnace. This emission limit must be met by
any furnace vent stacks.
(2) Mercury emissions. You must not discharge exhaust gases
(including primary and tapping emissions) containing mercury emissions
in excess of 16 [mu]g/dscm, corrected to 2 percent CO2 into
the atmosphere from any new, reconstructed or existing electric arc
furnace.
(3) Polycyclic aromatic hydrocarbon emissions. You must not
discharge exhaust gases (including primary and tapping emissions)
containing polycyclic aromatic hydrocarbon emissions in excess of 89
[mu]g/dscm, corrected to 2 percent CO2 into the atmosphere
from any new, reconstructed or existing electric arc furnace.
(4) Hydrochloric acid emissions. You must not discharge exhaust
gases (including primary and tapping emissions) containing hydrochloric
acid emissions in excess of 809 [mu]g/dscm, corrected to 2 percent
CO2 into the atmosphere from any new, reconstructed or
existing electric arc furnace.
(5) Formaldehyde emissions. You must not discharge exhaust gases
(including primary and tapping emissions) containing formaldehyde
emissions in excess of 201 [mu]g/dscm, corrected to 2 percent
CO2 into the atmosphere from any new, reconstructed or
existing electric arc furnace.
(b) Process fugitive emissions.
(1) You must install, operate, and maintain a capture system that
collects all of the process fugitive emissions from the shop building
(including tapping, casting, ladle treatment and crushing and screening
equipment process fugitives) at a negative pressure of at least 0.007
inches of water, and conveys the collected emissions to a control
device. You must not discharge into the atmosphere emissions from the
control device containing particulate matter in excess of 24 mg/dscm,
corrected to 2 percent CO2.
(2) You must not cause emissions exiting from a shop building, to
exceed 10 percent opacity for more than one 6-minute period.
(3) As an alternative to meeting the requirements specified in
paragraph (b)(1) of this section, you can elect to demonstrate
compliance by meeting the requirements of paragraphs (b)(3)(i) through
(b)(3)(ii) of this section.
(i) You must install compliance monitors on or near the plant
boundary, at locations approved by the Administrator, to demonstrate
that the manganese concentration in air is at all times maintained
below a 10-sample rolling average value of 0.10 [mu]g/m3 at each
monitor.
(A) Samples must be collected every 6 days. All samples are 24-hr
integrated samples.
(B) Calculate a 10-sample rolling average to demonstrate compliance
with the action level specified in paragraph (b)(3)(i) of this section.
Missed or invalidated samples must be made up only on the established
site-specific 1- in 6-day schedule to include the required number of
makeup samples to achieve a minimum of 10 valid samples).
(C) Collect particles in the PM10 size fraction at a set flow rate
of 16.7 l/minute using a 47 mm Teflon filter.
(D) Conduct the analysis using an EPA method (such as compendium
method IO-3.5) and ensure the manganese method detection limit (MDL) is
no greater than 0.01 [mu]g/m\3\.
(E) All data, to include values below MDL, must be reported. Under
no circumstances are data value substitutions (e.g., \1/2\ MDL)
acceptable.
(ii)(A) The monitoring system must include at least two ambient
monitors and at least one of these monitors must be in a location that
is expected to have the highest air concentrations at or near the
facility boundary based on ambient dispersion modeling or other methods
approved by the Administrator.
(B) You 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 the
justification for any data adjustments within 45 days after the
effective date of this subpart.
(C) The Administrator at any time may require changes in or
expansion of, the monitoring program, including additional sampling and
more frequent sampling, or revisions to the analytical protocols and
network design.
(c) Local ventilation emissions. If you operate local ventilation
to capture tapping, casting, or ladle treatment emissions and direct
them to a control device other than one associated with the electric
arc furnace, you must not discharge into the atmosphere any captured
emissions containing particulate matter in excess of 24 mg/dscm,
corrected to 2 percent CO2.
(d) MOR process. You must not discharge into the atmosphere from
any new, reconstructed or existing MOR process exhaust gases containing
particulate matter in excess of 3.9 mg/dscm, corrected to 2 percent
CO2.
(e) Crushing and screening equipment. You must not discharge into
the atmosphere from any new,
[[Page 72548]]
reconstructed, or existing piece of equipment associated with crushing
and screening exhaust gases containing particulate matter in excess of
13 mg/dscm.
(f) Emissions Averaging Option.
(1) As an alternative to meeting the emission standards specified
in paragraphs (a)(1) through (a)(6) of this section on an electric arc
furnace-specific basis, and if you have more than one existing electric
arc furnace located at one or more contiguous properties, which are
under common control of the same person (or persons under common
control), you may demonstrate compliance by emission averaging among
the existing electric arc furnaces, if your averaged emissions for such
electric arc furnaces are equal to or less than the applicable emission
limit.
(2) As an alternative to meeting the emission standard specified in
paragraph (b)(1) of this section on a building ventilation control
device-specific basis, and if you have more than one existing building
ventilation control device located at one or more contiguous
properties, which are under common control of the same person (or
persons under common control), you may demonstrate compliance by
emission averaging among the existing building ventilation control
devices, if your averaged emissions for such building ventilation
control devices are equal to or less than the applicable emission
limit.
(3) As an alternative to meeting the emission standard specified in
paragraph (e) of this section on a crushing and screening equipment
control device-specific basis, and if you have more than one existing
crushing and screening equipment control device located at one or more
contiguous properties, which are under common control of the same
person (or persons under common control), you may demonstrate
compliance by emission averaging among the existing crushing or
screening equipment control devices, if your averaged emissions for
such crushing or screening equipment control devices are equal to or
less than the applicable emission limit.
(g) The averaged emissions rate from the existing equipment
specified in paragraph (f) of this section participating in the
emissions averaging option must be in compliance with the emission
standards specified in paragraphs (a), (b) and (e) of this section by
the compliance date specified in Sec. 63.1621. You must develop, and
submit to the applicable regulatory authority for review and approval
upon request, an implementation plan for emission averaging according
to the following procedures and requirements in paragraphs (g)(1)
through (g)(4) of this section.
(1) You must submit the implementation plan no later than 180 days
before the date that the facility intends to demonstrate compliance
using the emission averaging option.
(2) You must include the information contained in paragraphs
(g)(2)(i) through (g)(2)(vii) of this section in your implementation
plan for all emission sources included in an emissions average:
(i) The identification of all existing equipment specified in
paragraph (f) of this section in the applicable averaging group,
including for each either the applicable HAP emission level or the
control technology installed as of [DATE 60 DAYS AFTER EFFECTIVE DATE
OF THE FINAL RULE] and the date on which you are requesting emission
averaging to commence;
(ii) A description of how you will comply with the monitoring
procedures specified in Sec. 63.1626 for each averaging group;
(iii) The specific control technology to be used for each piece of
equipment specified in paragraph (f) of this section in the averaging
group and the date of its installation or application;
(iv) The test plan for the measurement of particulate matter,
hydrochloric acid, formaldehyde and mercury emissions, as applicable,
in accordance with the requirements in Sec. 63.1625 and the planned
test dates to ensure that averaged units are tested concurrently or
with minimal differences in the testing dates;
(v) The operating parameters to be monitored for each control
system or device consistent with Sec. 63.1626 and a description of how
the operating limits will be determined;
(vi) If you request to monitor an alternative operating parameter
pursuant to Sec. 63.8, you must also include:
(A) A description of the parameter(s) to be monitored and an
explanation of the criteria used to select the parameter(s); and
(B) A description of the methods and procedures that will be used
to demonstrate that the parameter indicates proper operation of the
control device; the frequency and content of monitoring, reporting, and
recordkeeping requirements; and a demonstration, to the satisfaction of
the applicable regulatory authority, that the proposed monitoring
frequency is sufficient to represent control device operating
conditions; and
(vii) A demonstration that compliance with each of the applicable
emission limit(s) will be achieved under representative operating
conditions.
(3) The regulatory authority shall review and approve or disapprove
the plan according to the following criteria:
(i) Whether the content of the plan includes all of the information
specified in paragraph (g)(2) of this section; and
(ii) Whether the plan presents sufficient information to determine
that compliance will be achieved and maintained.
(4) The applicable regulatory authority shall not approve an
emission averaging implementation plan containing any of the following
provisions:
(i) Any averaging between emissions of differing pollutants or
between differing sources; or
(ii) The inclusion of any emission source other than an existing
unit in the same source category.
(h) At all times, you 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 that 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.
7. Section 63.1624 is added to read as follows:
Sec. 63.1624 What are the operational and work practice standards for
new, reconstructed and existing facilities?
(a) Process fugitives sources.
(1) If you are complying with the standard specified in Sec.
63.1623(b)(1), you must prepare and operate according to a process
fugitives ventilation plan for each shop building.
(2) You prepare a process fugitives ventilation schematic for each
shop building indicating duct size and location, enclosure and hood
sizes and locations, control device types, size and locations, and
exhaust locations should be developed. The process fugitives
ventilation system schematic must be annotated with the location and
size of each shop building air supply unit and each shop building
exhaust fan.
(3) You must conduct a baseline survey to establish actual air flow
and static pressure values before and after each emission control
device and in each branch of the process ventilation system after each
enclosure or hood. You must also determine actual air flow
[[Page 72549]]
and static pressure values for each shop building air supply and
exhaust device. You must demonstrate that air supply and exhaust are
balanced.
(4) You must repeat the baseline survey at least every 5 years or
following significant ventilation system changes.
(5) The process fugitives ventilation plan must contain a
description of each enclosure and hood with explanation demonstrating
that adequate control of the process source is being achieved or
actions planned to improve performance.
(6) The process fugitives ventilation plan must be adequate to
ensure that the building is continuously maintained at a negative
pressure of at least 0.007 inches of water.
(7) The process fugitives ventilation plan must identify critical
maintenance actions, schedule to complete, and verification record of
completion.
(8) You must submit a copy of the process fugitives ventilation
plan to the designated permitting authority on or before the applicable
compliance date for the affected source as specified in Sec. 63.1621.
The requirement for you to operate the facility according to a written
process fugitives ventilation plan must be incorporated in the
operating permit for the facility that is issued by the designated
permitting authority under part 70 of this chapter.
(b) Outdoor fugitive dust sources.
(1) You must prepare, and at all times operate according to, an
outdoor fugitive dust control plan that describes in detail the
measures that will be put in place to control outdoor fugitive dust
emissions from the individual fugitive dust sources at the facility.
(2) You must submit a copy of the outdoor fugitive dust control
plan to the designated permitting authority on or before the applicable
compliance date for the affected source as specified in Sec. 63.1621.
The requirement for you to operate the facility according to a written
outdoor fugitive dust control plan must be incorporated in the
operating permit for the facility that is issued by the designated
permitting authority under part 70 of this chapter.
(3) You are permitted to use existing manuals that describe the
measures in place to control outdoor fugitive dust sources required as
part of a State implementation plan or other federally enforceable
requirement for particulate matter to satisfy the requirements of
paragraph (b)(1) of this section.
8. Section 63.1625 is added to read as follows:
Sec. 63.1625 What are the performance test and compliance
requirements for new, reconstructed and existing facilities?
(a) Performance testing.
(1) All performance tests must be conducted according to the
requirements in Sec. 63.7 of subpart A.
(2) Each performance test must consist of three separate and
complete runs using the applicable test methods.
(3) Each run must be conducted under conditions that are
representative of normal process operations.
(4) Performance tests conducted on air pollution control devices
serving electric arc furnaces must be conducted such that at least one
tapping period, or at least 20 minutes of a tapping period, whichever
is less, is included in at least two of the three runs. The sampling
time for each run must be at least as long as three times the average
tapping period of the tested furnace, but no less than 60 minutes.
(5) You must conduct the performance tests specified in paragraph
(c) of this section under such conditions as the Administrator
specifies based on representative performance of the affected source
for the period being tested. Upon request, you must make available to
the Administrator such records as may be necessary to determine the
conditions of performance tests.
(b) Test methods. The following test methods in appendices of part
60 or 63 of this chapter or as specified elsewhere must be used to
determine compliance with the emission standards.
(1) Method 1 of Appendix A-1 of 40 CFR part 60 to select the
sampling port location and the number of traverse points.
(2) Method 2 of Appendix A-1 of 40 CFR part 60 to determine the
volumetric flow rate of the stack gas.
(3)(i) Method 3A or 3B of Appendix A-2 of 40 CFR part 60 (with
integrated bag sampling) to determine the outlet stack and inlet oxygen
and CO2 content.
(ii) You must measure CO2 concentrations at both the
inlet and outlet of the positive pressure fabric filter in conjunction
with the pollutant sampling in order to correct pollutant
concentrations for dilution and to determine isokinetic sampling rates.
(iii) As an alternative to EPA Reference Method 3B, ASME PTC-19-10-
1981-Part 10, ``Flue and Exhaust Gas Analyses'' may be used
(incorporated by reference, see 40 CFR 63.14).
(4) Method 4 of Appendix A-3 of 40 CFR part 60 to determine the
moisture content of the stack gas.
(5)(i) Method 5 of Appendix A-3 of 40 CFR part 60 to determine the
particulate matter concentration of the stack gas for negative pressure
baghouses and positive pressure baghouses with stacks.
(ii) Method 5D of Appendix A-3 of 40 CFR part 60 to determine
particulate matter concentration and volumetric flow rate of the stack
gas for positive pressure baghouses without stacks.
(iii) The sample volume for each run must be a minimum of 4.0 cubic
meters (141.2 cubic feet). For Method 5 testing only, you may choose to
collect less than 4.0 cubic meters per run provided that the filterable
mass collected (e.g., net filter mass plus mass of nozzle, probe and
filter holder rinses) is equal to or greater than 10 mg. If the total
mass collected for two of three of the runs is less than 10 mg, you
must conduct at least one additional test run that produces at least 10
mg of filterable mass collected (i.e., at a greater sample volume).
Report the results of all test runs.
(6) Method 30B of Appendix A-8 of 40 CFR part 60 to measure
mercury. Apply the minimum sample volume determination procedures as
per the method.
(7)(i) Method 26A of Appendix A-8 of 40 CFR part 60 to determine
outlet stack or inlet hydrochloric acid concentration.
(ii) Collect a minimum volume of 2 cubic meters.
(8)(i) Method 316 of Appendix A of 40 CFR part 63 to determine
outlet stack or inlet formaldehyde.
(ii) Collect a minimum volume of 1.0 cubic meter.
(9) Method 9 of Appendix A-4 of 40 CFR part 60 to determine
opacity. ASTM D7520-09, ``Standard Test Method for Determining the
Opacity of a Plume in the Outdoor Ambient Atmosphere'' may be used
(incorporated by reference, see 40 CFR 63.14) with the following
conditions:
(i) During the digital camera opacity technique (DCOT)
certification procedure outlined in Section 9.2 of ASTM D7520-09, you
or the DCOT vendor must present the plumes in front of various
backgrounds of color and contrast representing conditions anticipated
during field use such as blue sky, trees and mixed backgrounds (clouds
and/or a sparse tree stand).
(ii) You must also have standard operating procedures in place
including daily or other frequency quality checks to ensure the
equipment is within manufacturing specifications as outlined in Section
8.1 of ASTM D7520-09.
(iii) You must follow the recordkeeping procedures outlined in
Sec. 63.10(b)(1) for the DCOT certification, compliance report, data
sheets and all
[[Page 72550]]
raw unaltered JPEGs used for opacity and certification determination.
(iv) You or the DCOT vendor must have a minimum of four (4)
independent technology users apply the software to determine the
visible opacity of the 300 certification plumes. For each set of 25
plumes, the user may not exceed 15 percent opacity of any one reading
and the average error must not exceed 7.5 percent opacity.
(v) Use of this approved alternative does not provide or imply a
certification or validation of any vendor's hardware or software. The
onus to maintain and verify the certification and/or training of the
DCOT camera, software and operator in accordance with ASTM D7520-09 and
these requirements is on the facility, DCOT operator and DCOT vendor.
(10) Methods to determine the mercury content of manganese ore
including a total metals digestion technique, SW-846 Method 3052, and a
mercury specific analysis method, SW-846 Method 7471b (Cold Vapor AA)
or Water Method 1631E (Cold Vapor Atomic Fluorescence).
(11) California Air Resources Board (CARB) Method 429,
Determination of Polycyclic Aromatic Hydrocarbon (PAH) Emissions from
Stationary Sources to determine total PAH emissions. The method is
available from California Resources Board, 1102 Q Street, Sacramento,
California 95814, (http://www.arb.ca.gov/testmeth/vol3/M_429.pdf).
(12) The owner or operator may use alternative measurement methods
approved by the Administrator following the procedures described in
Sec. 63.7(f) of subpart A.
(c) Compliance demonstration with the emission standards.
(1) You must conduct an initial performance test for air pollution
control devices or vent stacks subject to Sec. 63.1623(a) through (e)
to demonstrate compliance with the applicable emission standards.
(2) You must conduct performance tests every 5 years for the air
pollution control devices and vent stacks associated with the electric
arc furnaces and furnace building ventilation systems. The results of
these periodic tests will be used to demonstrate compliance with the
emission standards in Sec. 63.1623(a)(1) through (a)(5), (b)(1) and
(b)(2), as applicable.
(3) For any air pollution control device that serves tapping
emissions combined with non-furnace emissions, such as the MOR process,
or equipment associated with crushing and screening, casting or ladle
treatment, you must conduct a performance test at least every 5 years.
The results of these tests will be used to demonstrate compliance with
the emission standards in Sec. 63.1623(c) through (e), as applicable.
(4) Compliance is demonstrated for all sources performing emissions
tests if the average concentration for the three runs comprising the
performance test does not exceed the standard or if you successfully
comply with the emission averaging option specified in Sec.
63.1623(f).
(5) Operating Limits. You must establish parameter operating limits
according to paragraphs (c)(5)(i) through (c)(5)(vi) of this section.
Unless otherwise specified, compliance with each established operating
limit shall be demonstrated for each 24-hour operating day.
(i) For a wet particulate matter scrubber, you must establish the
minimum liquid flow rate and pressure drop as your operating limits
during the three-run performance test. If you use a wet particulate
matter scrubber and you conduct separate performance tests for
particulate matter, you must establish one set of minimum liquid flow
rate and pressure drop operating limits. If you conduct multiple
performance tests, you must set the minimum liquid flow rate and
pressure drop operating limits at the highest minimum hourly average
values established during the performance tests.
(ii) For a wet acid gas scrubber, you must establish the minimum
liquid flow rate and pH, as your operating limits during the three-run
performance test. If you use a wet acid gas scrubber and you conduct
separate performance tests for hydrochloric acid, you must establish
one set of minimum liquid flow rate and pH operating limits. If you
conduct multiple performance tests, you must set the minimum liquid
flow rate and pH operating limits at the highest minimum hourly average
values established during the performance tests.
(iii) For a dry scrubber, dry sorbent injection (DSI) system or
activated carbon injection system, you must establish the minimum
hourly average sorbent or activated carbon injection rate, as measured
during the three-run performance test as your operating limit.
(iv) For emission sources with fabric filters that choose to
demonstrate continuous compliance through bag leak detection systems
you must install a bag leak detection system according to the
requirements in Sec. 63.1626(d), and you must set your operating limit
such that the sum duration of bag leak detection system alarms does not
exceed 5 percent of the process operating time during a 6-month period.
(v) If you choose to demonstrate continuous compliance through a
particulate matter CEMS, you must determine an operating limit
(particulate matter concentration in mg/dscm) during performance
testing for initial particulate matter compliance. The operating limit
will be the average of the PM filterable results of the three Method 5
or Method 5D of Appendix A-3 of 40 CFR part 60 performance test runs.
To determine continuous compliance, the hourly average PM
concentrations will be averaged on a rolling 30 operating day basis.
Each 30 operating day average would have to meet the PM operating
limit.
(v) For any furnace stack, you must establish a weighted average
mercury concentration of the manganese ore being used in the furnace
during the emission test. Collect a sample of all ores used in the
furnace and prepare a weighted average based on the relative mass of
each type of ore used in the furnace charge.
(d) Compliance demonstration with shop building opacity standards.
(1)(i) If you are subject to Sec. 63.1623(b)(2), you must conduct
initial opacity observations of the shop building to demonstrate
compliance with the applicable opacity standards according to Sec.
63.6(h)(5), which addresses the conduct of opacity or visible emission
observations.
(ii) You must conduct the opacity observations according to EPA
Method 9 of 40 CFR part 60, Appendix A-4, for a minimum of 60 minutes
to include at one, or at least 20 minutes of a tapping period,
whichever is less, in at least two of the three runs to coincide with
each performance test run of the associated control device.
(iii) Repeat this opacity observation at least every 5 years during
the periodic performance tests required pursuant to paragraph (c)(2) of
this section.
(2)(i) When demonstrating initial compliance with the shop building
opacity standard, as required by paragraph (d)(1) of this section, you
must simultaneously establish parameter values for one of the
following: The capture system fan motor amperes and all capture system
damper positions, the total volumetric flow rate to the air pollution
control device and all capture system damper positions, or volumetric
flow rate through each separately ducted hood that comprises the
capture system.
(ii) You may petition the Administrator to reestablish these
parameters whenever you can demonstrate to the Administrator's
satisfaction that the electric arc furnace operating conditions upon
which the
[[Page 72551]]
parameters were previously established are no longer applicable. The
values of these parameters determined during the most recent
demonstration of compliance must be maintained at the appropriate level
for each applicable period.
(iii) You will demonstrate compliance by installing, operating, and
maintaining a digital differential pressure device that shows you are
maintaining the shop building under negative pressure to at least 0.007
inches of water.
(3) You will demonstrate continuing compliance with the opacity
standards by following the monitoring requirements specified in Sec.
63.1626(h) and the reporting and recordkeeping requirements specified
in Sec. 63.1629(b)(5).
(e) Compliance demonstration with the operational and work practice
standards.
(1) Process fugitives sources. You will demonstrate compliance by
developing and maintaining a process fugitives ventilation plan, by
reporting any deviations from the plan and by taking necessary
corrective actions to correct deviations or deficiencies.
(2) Outdoor fugitive dust sources. You will demonstrate compliance
by developing and maintaining an outdoor fugitive dust control plan, by
reporting any deviations from the plan and by taking necessary
corrective actions to correct deviations or deficiencies.
(3) Baghouses equipped with bag leak detection systems. You will
demonstrate compliance with the bag leak detection system requirements
by developing analysis and supporting documentation demonstrating
conformance with EPA guidance and specifications for bag leak detection
systems in Sec. 60.57c(h).
9. Section 63.1626 is added to read as follows:
Sec. 63.1626 What monitoring requirements must I meet?
(a) Baghouse Monitoring. You must prepare, and at all times operate
according to, a standard operating procedures manual that describes in
detail procedures for inspection, maintenance, and bag leak detection
and corrective action plans for all baghouses (fabric filters or
cartridge filters) that are used to control process vents, process
fugitive, or outdoor fugitive dust emissions from any source subject to
the emissions standards in Sec. 63.1623, including those used to
control emissions from building ventilation.
(b) You must submit the standard operating procedures manual for
baghouses required by paragraph (a) of this section to the
Administrator or delegated authority for review and approval.
(c) Unless the baghouse is equipped with a bag leak detection
system, the procedures that you specify in the standard operating
procedures manual for inspections and routine maintenance must, at a
minimum, include the requirements of paragraphs (c)(1) and (c)(2) of
this section.
(1) You must observe the baghouse outlet on a daily basis for the
presence of any visible emissions.
(2) In addition to the daily visible emissions observation, you
must conduct the following activities:
(i) Weekly confirmation that dust is being removed from hoppers
through visual inspection, or equivalent means of ensuring the proper
functioning of removal mechanisms.
(ii) Daily check of compressed air supply for pulse-jet baghouses.
(iii) An appropriate methodology for monitoring cleaning cycles to
ensure proper operation.
(iv) Monthly check of bag cleaning mechanisms for proper
functioning through visual inspection or equivalent means.
(v) Quarterly visual check of bag tension on reverse air and
shaker-type baghouses to ensure that the bags are not kinked (kneed or
bent) or lying on their sides. Such checks are not required for shaker-
type baghouses using self-tensioning (spring loaded) devices.
(vi) Quarterly confirmation of the physical integrity of the
baghouse structure through visual inspection of the baghouse interior
for air leaks.
(vii) Semiannual inspection of fans for wear, material buildup, and
corrosion through visual inspection, vibration detectors, or equivalent
means.
(d) Bag leak detection system.
(1) For each baghouse used to control emissions from an electric
arc furnace or building ventilation system, you must install, operate,
and maintain a bag leak detection system according to paragraphs (d)(2)
through (d)(4) of this section, unless a system meeting the
requirements of paragraph (i) of this section, for a CEMS and
continuous emissions rate monitoring system, is installed for
monitoring the concentration of particulate matter. You may choose to
install, operate and maintain a bag leak detection system for any other
baghouse in operation at the facility according to paragraphs (d)(2)
through (d)(4) of this section.
(2) The procedures you specified in the standard operating
procedures manual for baghouse maintenance must include, at a minimum,
a preventative maintenance schedule that is consistent with the
baghouse manufacturer's instructions for routine and long-term
maintenance.
(3) Each bag leak detection system must meet the specifications and
requirements in paragraphs (d)(3)(i) through (d)(3)(viii) of this
section.
(i) The bag leak detection system must be certified by the
manufacturer to be capable of detecting PM emissions at concentrations
of 1.0 milligram per dry standard cubic meter (0.00044 grains per
actual cubic foot) or less.
(ii) The bag leak detection system sensor must provide output of
relative PM loadings.
(iii) The bag leak detection system must be equipped with an alarm
system that will alarm when an increase in relative particulate
loadings is detected over a preset level.
(iv) You must install and operate the bag leak detection system in
a manner consistent with the guidance provided in ``Office of Air
Quality Planning and Standards (OAQPS) Fabric Filter Bag Leak Detection
Guidance'' EPA-454/R-98-015, September 1997 (incorporated by reference)
and the manufacturer's written specifications and recommendations for
installation, operation, and adjustment of the system.
(v) 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.
(vi) Following initial adjustment, you must not adjust the
sensitivity or range, averaging period, alarm set points, or alarm
delay time, except as detailed in the approved standard operating
procedures manual required under paragraph (a) of this section. You
cannot increase the sensitivity by more than 100 percent or decrease
the sensitivity by more than 50 percent over a 365-day period unless
such adjustment follows a complete baghouse inspection that
demonstrates that the baghouse is in good operating condition.
(vii) You must install the bag leak detector downstream of the
baghouse.
(viii) Where multiple detectors are required, the system's
instrumentation and alarm may be shared among detectors.
(4) You must include in the standard operating procedures manual
required by paragraph (a) of this section a corrective action plan that
specifies the procedures to be followed in the case of a bag leak
detection system alarm. The corrective action plan must include, at a
minimum, the procedures that you will use to determine and record the
time and cause of the alarm as well as
[[Page 72552]]
the corrective actions taken to minimize emissions as specified in
paragraphs (d)(4)(i) and (d)(4)(ii) of this section.
(i) The procedures used to determine the cause of the alarm must be
initiated within 30 minutes of the alarm.
(ii) The cause of the alarm must be alleviated by taking the
necessary corrective action(s) that may include, but not be limited to,
those listed in paragraphs (d)(4)(i)(A) through (d)(4)(i)(F) of this
section.
(A) Inspecting the baghouse for air leaks, torn or broken filter
elements, or any other malfunction that may cause an increase in
emissions.
(B) Sealing off defective bags or filter media.
(C) Replacing defective bags or filter media, or otherwise
repairing the control device.
(D) Sealing off a defective baghouse compartment.
(E) Cleaning the bag leak detection system probe, or otherwise
repairing the bag leak detection system.
(F) Shutting down the process producing the particulate emissions.
(e) If you use a wet particulate matter scrubber, you must collect
the pressure drop and liquid flow rate monitoring system data according
to Sec. 63.1629, reduce the data to 24-hour block averages and
maintain the 24-hour average pressure drop and liquid flow-rate at or
above the operating limits established during the performance test
according to Sec. 63.1625(c)(5)(i).
(f) [Reserved]
(g) If you use a dry scrubber, DSI sorbent injection or carbon
injection, you must collect the sorbent or carbon injection rate
monitoring system data for the dry scrubber, DSI or ACI according to
Sec. 63.1629, reducing the data to 24-hour block averages; and
maintain the 24-hour average sorbent or carbon injection rate at or
above the operating limit established during the performance test
according to Sec. 63.1625(c)(5)(iii).
(h) Shop building opacity. In order to demonstrate continuous
compliance with the opacity standards in Sec. 63.1623, you must comply
with one of the monitoring options in paragraphs (h)(1), (h)(2), (h)(3)
or (h)(8) of this section. The selected option must be consistent with
that selected during the initial performance test described in Sec.
63.1625(d)(2). Alternatively, you may use the provisions of Sec.
63.8(f) to request approval to use an alternative monitoring method.
(1) You must check and record the control system fan motor amperes
and capture system damper positions once per shift.
(2) You must install, calibrate, and maintain a monitoring device
that continuously records the volumetric flow rate through each
separately ducted hood.
(3) You must install, calibrate, and maintain a monitoring device
that continuously records the volumetric flow rate at the inlet of the
air pollution control device and check and record the capture system
damper positions once per shift.
(4) The flow rate monitoring devices must meet the following
requirements:
(i) Be installed in an appropriate location in the exhaust duct
such that reproducible flow rate monitoring will result.
(ii) Have an accuracy 10 percent over its normal
operating range and be calibrated according to the manufacturer's
instructions.
(5) The Administrator may require you to demonstrate the accuracy
of the monitoring device(s) relative to Methods 1 and 2 of Appendix A-1
of part 60 of this chapter.
(6) Failure to maintain the appropriate capture system parameters
(fan motor amperes, flow rate, and/or damper positions) establishes the
need to initiate corrective action as soon as practicable after the
monitoring excursion in order to minimize excess emissions.
(7) You must install, operate, and maintain a digital differential
pressure monitoring system to continuously monitor each total enclosure
as described in paragraphs (h)(7)(i) through (h)(7)(v) of this section.
(i) You must install and maintain a minimum of one building digital
differential pressure monitoring system at each of the following three
walls in the shop building:
(A) The leeward wall.
(B) The windward wall.
(C) An exterior wall that connects the leeward and windward wall at
a location defined by the intersection of a perpendicular line between
a point on the connecting wall and a point on its furthest opposite
exterior wall, and intersecting within plus or minus ten meters of the
midpoint of a straight line between the two other monitors specified.
The midpoint monitor must not be located on the same wall as either of
the other two monitors.
(ii) The digital differential pressure monitoring systems must be
certified by the manufacturer to be capable of measuring and displaying
negative pressure in the range of 0.01 to 0.2 mm mercury (0.005 to 0.11
inches of water) with a minimum accuracy of plus or minus 0.001 mm
mercury (0.0005 inches of water).
(iii) You must equip each digital differential pressure monitoring
system with a continuous recorder.
(iv) You must calibrate each digital differential pressure
monitoring system in accordance with manufacturer's specifications at
least once every 12 calendar months or more frequently if recommended
by the manufacturer.
(v) You must equip the digital differential pressure monitoring
system with a backup, uninterruptible power supply to ensure continuous
operation of the monitoring system during a power outage.
(8) If you comply with the requirements specified in Sec.
63.1623(b)(3), you must install, operate and maintain a continuous
monitoring system for the measurement of manganese concentrations in
air as specified in paragraphs (h)(8)(i) through (h)(8)(v) of this
section.
(i) You must operate a minimum of two compliance monitors
sufficient in location and frequency of sample collection to detect
expected maximum concentrations of manganese in air due to emissions
from the affected source(s) in accordance with a written plan as
described in paragraph (h)(8)(ii) of this section and approved by the
Administrator. The plan must include descriptions of the sampling and
analytical methods used. At least one 24-hour sample must be collected
from each monitor every 6 days. All records pertaining to the
implementation and results of the compliance monitoring shall be kept
on-site for a period of no less than 5 years from the date of
generation of the record.
(ii) You must submit a written plan describing and explaining the
basis for the design and adequacy of the compliance monitoring network,
the sampling, sample handling and custody, analytical procedures,
quality assurance procedures, recordkeeping procedures and any other
related procedures, and the justification for any seasonal, background,
or other data adjustments within [45 DAYS AFTER EFFECTIVE DATE OF FINAL
RULE].
(iii) The Administrator at any time may require changes in, or
expansion of, the monitoring program, including additional sampling
and, more frequent sampling, revisions to the analytical protocols and
network design.
(iv) If all rolling 10-sample average concentrations of manganese
in air measured by the compliance monitoring system are less than 50
percent of the manganese concentration limits specified in Sec.
63.1623(b)(3)(i) for 3 consecutive years, you may submit a proposed
revised plan to reduce the monitoring sampling and analysis
[[Page 72553]]
frequency to the Administrator for review. If approved by the
Administrator, you may adjust your monitoring accordingly.
(v) For any subsequent period, if any rolling 10-sample average
manganese concentration in air measured at any monitor in the
monitoring system exceeds 50 percent of the concentration limits
specified in Sec. 63.1623(b)(3), you must resume monitoring pursuant
to paragraph (h)(8)(i)(A) of this section at all monitors until another
3 consecutive years of manganese concentration measurements is
demonstrated to be less than 50 percent of the manganese concentration
limits specified in Sec. 63.1623(b)(3).
(i) Furnace Capture System. You must perform monthly inspections of
the equipment that is important to the performance of the furnace
capture system, including capture of both primary and tapping
emissions. This inspection must include an examination of the physical
condition of the equipment (e.g., has hood location been changed or
obstructed because of contact with cranes or ladles), to include
detecting holes in ductwork or hoods, flow constrictions in ductwork
due to dents or accumulated dust, and operational status of flow rate
controllers (pressure sensors, dampers, damper switches, etc.). Any
deficiencies must be recorded and proper maintenance and repairs
performed.
(j) Requirements for sources using CMS. If you demonstrate
compliance with any applicable emissions limit through use of a
continuous monitoring system (CMS), where a CMS includes a continuous
parameter monitoring system (CPMS) as well as a continuous emissions
monitoring system (CEMS), you must develop a site-specific monitoring
plan and submit this site-specific monitoring plan, if requested, at
least 60 days before your initial performance evaluation (where
applicable) of your CMS. Your site-specific monitoring plan must
address the monitoring system design, data collection, and the quality
assurance and quality control elements outlined in this section and in
Sec. 63.8(d). You must install, operate, and maintain each CMS
according to the procedures in your approved site-specific monitoring
plan. Using the process described in Sec. 63.8(f)(4), you may request
approval of monitoring system quality assurance and quality control
procedures alternative to those specified in paragraphs (j)(1) through
(j)(6) of this section in your site-specific monitoring plan.
(1) The performance criteria and design specifications for the
monitoring system equipment, including the sample interface, detector
signal analyzer and data acquisition and calculations;
(2) Sampling interface location such that the monitoring system
will provide representative measurements;
(3) Equipment performance checks, system accuracy audits, or other
audit procedures;
(4) Ongoing operation and maintenance procedures in accordance with
the general requirements of Sec. 63.8(c)(1) and (c)(3); and
(5) Conditions that define a continuous monitoring system that is
out of control consistent with Sec. 63.8(c)(7)(i) and for responding
to out of control periods consistent with Sec. 63.8(c)(7)(ii) and
(c)(8) or Appendix A to this subpart, as applicable.
(6) Ongoing recordkeeping and reporting procedures in accordance
with provisions in Sec. 63.10(c), (e)(1) and (e)(2)(i) and Appendix A
to this subpart, as applicable.
(k) If you have an operating limit that requires the use of a CPMS,
you must install, operate, and maintain each continuous parameter
monitoring system according to the procedures in paragraphs (k)(1)
through (k)(7) of this section.
(1) The continuous parameter monitoring system must complete a
minimum of one cycle of operation for each successive 15-minute period.
You must have a minimum of four successive cycles of operation to have
a valid hour of data.
(2) 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, system accuracy audits and required zero and span
adjustments), you must operate the CMS at all times the affected source
is operating. A monitoring system malfunction is any sudden,
infrequent, not reasonably preventable failure of the monitoring system
to provide valid data. Monitoring system failures that are caused in
part by poor maintenance or careless operation are not malfunctions.
You are required to complete monitoring system repairs in response to
monitoring system malfunctions and to return the monitoring system to
operation as expeditiously as practicable.
(3) You may not use data recorded during monitoring system
malfunctions, repairs associated with monitoring system malfunctions,
or required monitoring system quality assurance or control activities
in calculations used to report emissions or operating levels. You must
use all the data collected during all other required data collection
periods in assessing the operation of the control device and associated
control system.
(4) Except for periods of monitoring system malfunctions, repairs
associated with monitoring system malfunctions, and required quality
monitoring system quality assurance or quality control activities
(including, as applicable, system accuracy audits and required zero and
span adjustments), failure to collect required data is a deviation of
the monitoring requirements.
(5) You must conduct other CPMS equipment performance checks,
system accuracy audits, or other audit procedures specified in your
site-specific monitoring plan at least once every 12 months.
(6) You must conduct a performance evaluation of each CPMS in
accordance with your site-specific monitoring plan.
(7) You must record the results of each inspection, calibration,
and validation check.
(l) CPMS for measuring gaseous flow.
(1) Use a flow sensor with a measurement sensitivity of 5 percent
of the flow rate or 10 cubic feet per minute, whichever is greater,
(2) Check all mechanical connections for leakage at least every
month, and
(3) Perform a visual inspection at least every 3 months of all
components of the flow CPMS for physical and operational integrity and
all electrical connections for oxidation and galvanic corrosion if your
flow CPMS is not equipped with a redundant flow sensor.
(m) CPMS for measuring liquid flow.
(1) Use a flow sensor with a measurement sensitivity of 2 percent
of the flow rate and
(2) Reduce swirling flow or abnormal velocity distributions due to
upstream and downstream disturbances.
(n) CPMS for measuring pressure.
(1) Minimize or eliminate pulsating pressure, vibration, and
internal and external corrosion and
(2) Use a gauge with a minimum tolerance of 1.27 centimeters of
water or a transducer with a minimum tolerance of 1 percent of the
pressure range.
(3) Perform checks at least once each process operating day to
ensure pressure measurements are not obstructed (e.g., check for
pressure tap pluggage daily).
(o) CPMS measuring flow of sorbent or carbon (e.g., weigh belt,
weigh hopper, or hopper flow measurement device). Install and calibrate
the device in accordance with manufacturer's procedures and
specifications.
(p) CPMS for measuring pH.
(1) Ensure the sample is properly mixed and representative of the
fluid to be measured.
[[Page 72554]]
(2) Check the pH meter's calibration on at least two points every 8
hours of process operation.
(q) Particulate Matter CEMS. If you are using a CEMS to measure
particulate matter emissions to meet requirements of this subpart, you
must install, certify, operate, and maintain the particulate matter
CEMS as specified in paragraphs (q)(1) through (q)(4) of this section.
(1) You must conduct a performance evaluation of the PM CEMS
according to the applicable requirements of Sec. 60.13, and
Performance Specification 11 at 40 CFR part 60, Appendix B of this
chapter.
(2) During each PM correlation testing run of the CEMS required by
Performance Specification 11 at 40 CFR part 60, Appendix B of this
chapter, PM and oxygen (or carbon dioxide) collect data concurrently
(or within a 30- to 60-minute period) by both the CEMS and by
conducting performance tests using Method 5 or 5D at 40 CFR part 60,
Appendix A-3 or Method 17 at 40 CFR part 60, Appendix A-6 of this
chapter.
(3) Perform quarterly accuracy determinations and daily calibration
drift tests in accordance with Procedure 2 at 40 CFR part 60, Appendix
F of this chapter. Relative Response Audits must be performed annually
and Response Correlation Audits must be performed every 3 years.
(4) Within 60 days after the date of completing each CEMS relative
accuracy test audit or performance test conducted to demonstrate
compliance with this subpart, you must submit the relative accuracy
test audit data and performance test data to the EPA by successfully
submitting the data electronically into the EPA's Central Data Exchange
by using the Electronic Reporting Tool (see http://www.epa.gov/ttnchie1/ert/).
(r) Ore Sampling Requirements.
(1) Following completion of the initial compliance demonstration
where you established a weighted average mercury concentration of the
manganese ore being used in the furnace during the emission test, you
must determine the weighted average mercury concentration of the
manganese ores used in the process on a monthly basis. If you introduce
a new type of ore, you must analyze the sample according the methods
specified in Sec. 63.1625(b)(10) and factor the results into your
updated weighted average mercury concentration.
(2) If the weighted average mercury concentration is more than 10
percent higher than the weighted average operating limit, and you are
operating an activated carbon injection system, you must reassess the
activated carbon injection rate and revise the rate according to
procedures established in your CMS monitoring plan.
(3) If the weighted average mercury concentration is more than 10
percent higher than the weighted average operating limit, and you are
not operating an activated carbon injection system, you must retest the
control device within 30 days to demonstrate compliance with the
mercury emission limit and establish a new weighted average mercury
concentration and associated activated carbon injection rate.
10. Section 63.1627 is added to read as follows:
Sec. 63.1627 What is an affirmative defense for exceedence of an
emissions limit during malfunction?
In response to an action to enforce the standards set forth in
paragraph Sec. 63.1623 you may assert an affirmative defense to a
claim for civil penalties for exceedances of such standards that are
caused by malfunction, as defined at 40 CFR 63.2. Appropriate penalties
may be assessed, however, if the respondent fails to meet its burden of
proving all of the requirements in the affirmative defense. The
affirmative defense shall not be available for claims for injunctive
relief.
(a) Affirmative Defense. To establish the affirmative defense in
any action to enforce such a limit, you must 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, 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
(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, 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, consistent with safety and good air
pollution control practices; 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, the purpose of
which is 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.
(1) If you experience an exceedence of the facilities' emission
limit(s) during a malfunction, you must notify the EPA Administrator by
telephone or facsimile (Fax) transmission as soon as possible, but no
later than two (2) business days after the initial occurrence of the
malfunction, if you wish to avail yourself of an affirmative defense to
civil penalties for that malfunction.
(2) You must also submit a written report to the EPA Administrator,
within 45 days of the initial occurrence of the exceedence of the
standard in Sec. 63.1623, to demonstrate, with all necessary
supporting documentation, that you have met the requirements set forth
in paragraph (a) of this section.
(3) You may seek an extension of this deadline for up to 30
additional days by submitting a written request to the Administrator
before the expiration of the 45-day period. Until a request for an
extension has been approved by the Administrator, you are subject to
the requirement to submit such report within 45 days of the initial
occurrence of the exceedances.
11. Section 63.1628 is added to read as follows:
Sec. 63.1628 What notification requirements must I meet?
(a) You must comply with all of the notification requirements of
Sec. 63.9 of subpart A, General Provisions.
[[Page 72555]]
Electronic notifications are encouraged when possible.
(b)(1) You must submit the process fugitives ventilation plan
required under Sec. 63.1624(a), the outdoor fugitive dust control plan
required under Sec. 63.1624(b), the site-specific monitoring plan for
CMS required under Sec. 63.1626(j), the standard operating procedures
manual for baghouses required under Sec. 63.1626(a) and the manganese
monitoring alternative plan required under Sec. 63.1626(h)(8) to the
Administrator or delegated authority along with a notification that you
are seeking review and approval of these plans and procedures. You must
submit this notification no later than [1 YEAR AFTER EFFECTIVE DATE OF
FINAL RULE]. For sources that commenced construction or reconstruction
after [EFFECTIVE DATE OF FINAL RULE], you must submit this notification
no later than 180 days before startup of the constructed or
reconstructed ferromanganese or silicomanganese production facility.
For an affected source that has received a construction permit from the
Administrator or delegated authority on or before [EFFECTIVE DATE OF
FINAL RULE], you must submit this notification no later than [1 YEAR
AFTER EFFECTIVE DATE OF FINAL RULE].
(2) The plans and procedures documents submitted as required under
paragraph (b)(1) of this section must be submitted to the Administrator
in electronic format for review and approval of the initial submittal
and whenever an update is made to the procedure.
12. Section 63.1629 is added to read as follows:
Sec. 63.1629 What recordkeeping and reporting requirements must I
meet?
(a) You must comply with all of the recordkeeping and reporting
requirements specified in Sec. 63.10 of the General Provisions that
are referenced in Table 1 to this subpart.
(1) Records must be maintained in a form suitable and readily
available for expeditious review, according to Sec. 63.10(b)(1).
However, electronic recordkeeping and reporting is encouraged, and
required for some records and reports.
(2) Records must be kept on site for at least 2 years after the
date of occurrence, measurement, maintenance, corrective action,
report, or record, according to Sec. 63.10(b)(1).
(b) You must maintain, for a period of 5 years, records of the
information listed in paragraphs (b)(1) through (b)(13) of this
section.
(1) Electronic records of the bag leak detection system output.
(2) 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 corrective actions taken, and the date and time the
cause of the alarm was corrected.
(3) All records of inspections and maintenance activities required
under Sec. 63.1626(a) as part of the practices described in the
standard operating procedures manual for baghouses required under Sec.
63.1626(c).
(4) Electronic records of the pressure drop and water flow rate
values for wet scrubbers used to control particulate matter emissions
as required in Sec. 63.1626(e), identification of periods when the 1-
hour average pressure drop and water flow rate values below the
established minimum established and an explanation of the corrective
actions taken.
(5) Electronic records of the shop building capture system
monitoring required under Sec. 63.1626(h)(1) through (h)(3), (h)(7)
and (h)(8), as applicable, identification of periods when the capture
system parameters were not maintained or the manganese concentration
exceeded the rolling 10-sample concentration level as required under
Sec. 63.1623(b)(3) and an explanation of the corrective actions taken.
(6) Records of the results of monthly inspections of the furnace
capture system required under Sec. 63.1626(i).
(7) Electronic records of the continuous flow monitors or pressure
monitors required under Sec. 63.1626(j) and (k) and an identification
of periods when the flow rate or pressure was not maintained as
required in Sec. 63.1626(e).
(8) Electronic records of the output of any CEMS installed to
monitor particulate matter emissions meeting the requirements of Sec.
63.1626(j).
(9) Records of the total sorbent injection rate required under
Sec. 63.1626(k).
(10) Records of the occurrence and duration of each startup and/or
shutdown.
(11) Records of the occurrence and duration of each malfunction of
operation (i.e., process equipment) or the air pollution control
equipment and monitoring equipment.
(12) Records of actions taken during periods of malfunction to
minimize emissions in accordance with Sec. 63.1623(g), including
corrective actions to restore malfunctioning process and air pollution
control and monitoring equipment to its normal or usual manner of
operation.
(13) Records that explain the periods when the procedures outlined
in the process fugitives ventilation plan required under Sec.
63.1624(a), the fugitives dust control plan required under Sec.
63.1624(b), the site-specific monitoring plan for CMS required under
Sec. 63.1626(j), the standard operating procedures manual for
baghouses required under Sec. 63.1626(a) and the manganese monitoring
alternative plan required under Sec. 63.1626(h)(8) were not followed
and the corrective actions taken.
(c) You must comply with all of the reporting requirements
specified in Sec. 63.10 of the General Provisions that are referenced
in Table 1 to this subpart.
(1) You must submit reports no less frequently than specified under
Sec. 63.10(e)(3) of the General Provisions.
(2) Once a source reports a violation of the standard or excess
emissions, you must follow the reporting format required under Sec.
63.10(e)(3) until a request to reduce reporting frequency is approved
by the Administrator.
(d) In addition to the information required under the applicable
sections of Sec. 63.10, you must include in the reports required under
paragraph (c) of this section the information specified in paragraphs
(d)(1) through (d)(8) of this section.
(1) Reports that explain the periods when the procedures outlined
in the process fugitives ventilation plan required under Sec.
63.1624(a), the fugitives dust control plan required under Sec.
63.1624(b), the site-specific monitoring plan for CMS required under
Sec. 63.1626(j), the standard operating procedures manual for
baghouses required under Sec. 63.1626(a) and the manganese monitoring
alternative plan required under Sec. 63.1626(h)(8) were not followed
and the corrective actions taken.
(2) Reports that identify the periods when the average hourly
pressure drop or flow rate of venturi scrubbers used to control
particulate emissions dropped below the levels established in Sec.
63.1626(e) and an explanation of the corrective actions taken.
(3) Bag leak detection system. Reports including the following
information:
(i) Records of all alarms.
(ii) Description of the actions taken following each bag leak
detection system alarm.
(4) Reports of the shop building capture system monitoring required
under Sec. 63.1626(h)(1) through (h)(3), (h)(7) and (h)(8), as
applicable, identification of periods when the capture system
parameters were not
[[Page 72556]]
maintained or the manganese concentration exceeded the rolling 10-
sample concentration level as required under Sec. 63.1623(b)(3) and an
explanation of the corrective actions taken.
(5) Reports of the results of monthly inspections of the furnace
capture system required under Sec. 63.1626(g).
(6) Reports of the CPMS required under Sec. 63.1626, an
identification of periods when the monitored parameters were not
maintained as required in Sec. 63.1626, and corrective actions taken.
(7) If a malfunction occurred during the reporting period, the
report must include the number, duration, and a brief description for
each type of malfunction that occurred during the reporting period and
caused or may have caused any applicable emissions 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. 63.1623(g), including
actions taken to correct a malfunction.
(8) You must submit records pursuant to paragraphs (d)(8)(i)
through (d)(8)(iii) of this section.
(i) Within 60 days after the date of completing each performance
test, as defined in Sec. 63.2 and as required in this subpart, you
must submit performance test data, except opacity data, electronically
to the EPA's Central Data Exchange by using the Electronic Reporting
Tool (see http://www.epa.gov/ttnchie1/ert/). Only data collected using
test methods compatible with the Electronic Reporting Tool are subject
to this requirement to be submitted electronically into the EPA's
WebFIRE database.
(ii) Within 60 days after the date of completing each CEMS
performance evaluation test, as defined in Sec. 63.2 and required by
this subpart, you must submit the relative accuracy test audit data
electronically into the EPA's Central Data Exchange by using the
Electronic Reporting Tool as mentioned in paragraph (d)(8)(i) of this
section. Only data collected using test methods compatible with the
Electronic Reporting Tool are subject to this requirement to be
submitted electronically into the EPA's WebFIRE database.
(iii) All reports required by this subpart not subject to the
requirements in paragraph (d)(8)(i) and (d)(8)(ii) of this section must
be sent to the Administrator at the appropriate address listed in Sec.
63.13. The Administrator or the delegated authority may request a
report in any form suitable for the specific case (e.g., by electronic
media such as Excel spreadsheet, on CD or hard copy). The Administrator
retains the right to require submittal of reports subject to paragraph
(d)(9)(i) and (d)(9)(ii) of this section in paper format.
13. Section 63.1630 is added to read as follows:
Sec. 63.1630 Who implements and enforces this subpart?
(a) This subpart can be implemented and enforced by the U.S. EPA,
or a delegated authority such as the applicable state, local, or tribal
agency. If the U.S. EPA Administrator has delegated authority to a
state, local, or tribal agency, then that agency, in addition to the
U.S. EPA, has the authority to implement and enforce this subpart.
Contact the applicable U.S. EPA Regional Office to find out if this
subpart is delegated to a state, local, or tribal agency.
(b) In delegating implementation and enforcement authority of this
subpart to a state, local, or tribal agency under subpart E of this
part, the authorities contained in paragraph (c) of this section are
retained by the Administrator of U.S. EPA and cannot be transferred to
the state, local, or tribal agency.
(c) The authorities that cannot be delegated to state, local, or
tribal agencies are as specified in paragraphs (c)(1) through (c)(4) of
this section.
(1) Approval of alternatives to requirements in Sec. Sec. 63.1620
and 63.1621 and 63.1623 and 63.1624.
(2) Approval of major alternatives to test methods under Sec.
63.7(e)(2)(ii) and (f), as defined in Sec. 63.90, and as required in
this subpart.
(3) Approval of major alternatives to monitoring under Sec.
63.8(f), as defined in Sec. 63.90, and as required in this subpart.
(4) Approval of major alternatives to recordkeeping and reporting
under Sec. 63.10(f), as defined in Sec. 63.90, and as required in
this subpart.
14. Section 63.1650 is amended by:
a. Revising paragraph (d);
b. Removing and reserving paragraph (e)(1); and
c. Revising paragraph (e)(2) to read as follows:
Sec. 63.1650 Applicability and Compliance Dates.
* * * * *
(d) Table 1 to this subpart specifies the provisions of subpart A
of this part that apply to owners and operators of ferroalloy
production facilities subject to this subpart.
(e) * * *
(1) [Reserved]
(2) Each owner or operator of a new or reconstructed affected
source that commences construction or reconstruction after August 4,
1998 and before November 23, 2011 must comply with the requirements of
this subpart by May 20, 1999 or upon startup of operations, whichever
is later.
15. Section 63.1651 is amended by adding a definition for
``Affirmative defense'' in alphabetic order to read as follows:
Sec. 63.1651 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.
* * * * *
16. Section 63.1652 is amended by adding paragraph (f) to read as
follows:
Sec. 63.1652 Emission standards.
* * * * *
(f) At all times, you 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 that 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.
17. Section 63.1656 is amended by:
a. Adding paragraph (a)(6);
b. Revising paragraph (e)(1); and
c. Removing and reserving paragraph (e)(2)(ii) to read as follows:
Sec. 63.1656 Performance testing, test methods, and compliance
demonstrations.
(a) * * *
(6) You must conduct the performance tests specified in paragraph
(c) of this section under such conditions as the Administrator
specifies based on representative performance of the affected source
for the period being tested. Upon request, you must make available to
the Administrator such records as may be necessary to determine the
conditions of performance tests.
* * * * *
(e) * * *
(1) Fugitive dust sources. Failure to have a fugitive dust control
plan or failure to report deviations from the plan and take necessary
corrective action would be a violation of the
[[Page 72557]]
general duty to ensure that fugitive dust sources are operated and
maintained in a manner consistent with good air pollution control
practices for minimizing emissions per Sec. 63.1652(f).
(2) * * *
(ii) [Reserved]
* * * * *
18. Section 63.1657 is amended by:
a. Revising paragraph (a)(6);
b. Revising paragraph (b)(3); and
c. Revising paragraph (c)(7) to read as follows:
Sec. 63.1657 Monitoring requirements.
(a) * * *
(6) Failure to monitor or failure to take corrective action under
the requirements of paragraph (a) of this section would be a violation
of the general duty to operate in a manner consistent with good air
pollution control practices that minimizes emissions per Sec.
63.1652(f).
(b) * * *
(3) Failure to monitor or failure to take corrective action under
the requirements of paragraph (b) of this section would be a violation
of the general duty to operate in a manner consistent with good air
pollution control practices that minimizes emissions per Sec.
63.1652(f).
(c) * * *
(7) Failure to monitor or failure to take corrective action under
the requirements of paragraph (c) of this section would be a violation
of the general duty to operate in a manner consistent with good air
pollution control practices that minimizes emissions per Sec.
63.1652(f).
19. Section 63.1659 is amended by revising paragraph (a)(4) to read
as follows:
(a) * * *
(4) Reporting malfunctions. If a malfunction occurred during the
reporting period, the report must 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. 63.1652(f), including actions taken to correct a
malfunction.
* * * * *
20. Section 63.1660 is amended by:
a. Revising paragraphs (a)(2)(i) and (a)(2)(ii); and
b. Removing and reserving paragraphs (a)(2)(iv) and (a)(2)(v) to
read as follows:
(a) * * *
(2) * * *
(i) Records of the occurrence and duration of each malfunction of
operation (i.e., process equipment) or the air pollution control
equipment and monitoring equipment;
(ii) Records of actions taken during periods of malfunction to
minimize emissions in accordance with Sec. 63.1652(f), including
corrective actions to restore malfunctioning process and air pollution
control and monitoring equipment to its normal or usual manner of
operation;
* * * * *
(iv) [Reserved]
(v) [Reserved]
* * * * *
21. Section 63.1662 is added to read as follows:
Sec. 63.1662 Affirmative defense for exceedance of emission limit
during malfunction.
In response to an action to enforce the standards set forth in
Sec. 63.1652 through Sec. 63.1654 you may assert an affirmative
defense to a claim for civil penalties for exceedances of such
standards that are caused by malfunction, as defined at 40 CFR 63.2.
Appropriate penalties may be assessed, however, if you fail to meet
your burden of proving all of 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, 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
(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, 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, consistent with safety and good air
pollution control practices; 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 affected source was operated in a manner
consistent with good practices for minimizing emissions; and
(9) A written root cause analysis has been prepared, the purpose of
which is 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 affected source
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
45 days of the initial occurrence of the exceedance of the standard in
Sec. 63.1652 through Sec. 63.1654 to demonstrate, with all necessary
supporting documentation, that it has met the requirements set forth in
paragraph (a) of this section. The owner or operator may seek an
extension of this deadline for up to 30 additional days by submitting a
written request to the Administrator before the expiration of the 45
day period. Until a request for an extension has been approved by the
Administrator, the owner or operator is subject to the requirement to
submit such report within 45 days of the initial occurrence of the
exceedance.
22. Add Table 1 to the end of subpart XXX to read as follows:
[[Page 72558]]
Table 1 to Subpart XXX of Part 63--General Provisions Applicability to
Subpart XXX
------------------------------------------------------------------------
Applies to
Reference subpart XXX Comment
------------------------------------------------------------------------
63.1.......................... Yes. .....................
63.2.......................... Yes. .....................
63.3.......................... Yes. .....................
63.4.......................... Yes. .....................
63.5.......................... Yes. .....................
63.6(a), (b), (c)............. Yes. .....................
63.6(d)....................... No Section reserved.
63.6(e)(1)(i)................. No See 63.1623(g) and
63.1652(f) for
general duty
requirement.
63.6(e)(1)(ii)................ No. .....................
63.6(e)(1)(iii)............... Yes. .....................
63.6(e)(2).................... No Section reserved.
63.6(e)(3).................... No. .....................
63.6(f)(1).................... No. .....................
6.6(f)(2)-(f)(3)..............
63.6(g)....................... Yes. .....................
63.6(h)(1).................... No. .....................
63.6(h)(2)-(h)(9)............. Yes. .....................
63.6(i)....................... Yes. .....................
63.6(j)....................... Yes. .....................
Sec. 63.7(a)-(d)............ Yes. .....................
Sec. 63.7(e)(1)............. No See 63.1625(a)(5) and
63.1656(a)(6).
Sec. 63.7(e)(2)-(e)(4)...... Yes. .....................
63.7(f), (g), (h)............. Yes. .....................
63.8(a)-(b)................... Yes. .....................
63.8(c)(1)(i)................. No See 63.1623(g) and
63.1652(f) for
general duty
requirement.
63.8(c)(1)(ii)................ Yes. .....................
63.8(c)(1)(iii)............... No. .....................
63.8(c)(2)-(d)(2)............. Yes. .....................
63.8(d)(3).................... Yes, except for .....................
last sentence.
63.8(e)-(g)................... Yes. .....................
63.9(a), (b), (c), (e), (g), Yes. .....................
(h)(1) through (3), (h)(5)
and (6), (i) and (j).
63.9(f)....................... Yes. .....................
63.9(h)(4).................... No Reserved.
63.10 (a)..................... Yes. .....................
63.10 (b)(1).................. Yes. .....................
63.10(b)(2)(i)................ No. .....................
63.10(b)(2)(ii)............... No See 63.1629 and
63.1660 for
recordkeeping of
occurrence and
duration of
malfunctions and
recordkeeping of
actions taken during
malfunction.
63.10(b)(2)(iii).............. Yes. .....................
63.10(b)(2)(iv)-(b)(2)(v)..... No. .....................
63.10(b)(2)(vi)-(b)(2)(xiv)... Yes. .....................
63.(10)(b)(3)................. Yes. .....................
63.10(c)(1)-(9)............... Yes. .....................
63.10(c)(10)-(11)............. No See 63.1629 and
63.1630 for
recordkeeping of
malfunctions.
63.10(c)(12)-(c)(14).......... Yes. .....................
63.10(c)(15).................. No. .....................
63.10(d)(1)-(4)............... Yes. .....................
63.10(d)(5)................... No See 63.1629(d)(8) and
63.1659(a)(4) for
reporting of
malfunctions.
63.10(e)-((f)................. Yes. .....................
63.11......................... No Flares will not be
used to comply with
the emission limits.
63.12 to 63.15................ Yes. .....................
------------------------------------------------------------------------
[FR Doc. 2011-29455 Filed 11-22-11; 8:45 am]
BILLING CODE 6560-50-P