[Federal Register Volume 85, Number 100 (Friday, May 22, 2020)]
[Proposed Rules]
[Pages 31118-31124]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-10586]
[[Page 31118]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[EPA-R09-OAR-2020-0109; FRL-10008-99-Region 9]
Partial Approval and Partial Disapproval of Air Quality
Implementation Plans; Arizona; Nonattainment Plan for the Hayden SO2
Nonattainment Area
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: The Environmental Protection Agency (EPA) is proposing to
partially approve and partially disapprove an Arizona state
implementation plan (SIP) revision for attaining the 2010 1-hour
primary sulfur dioxide (SO2) national ambient air quality
standard (NAAQS or ``standard'') for the Hayden SO2
nonattainment area (NAA). This SIP revision (hereinafter called the
``Hayden SO2 Plan'' or ``Plan'') includes Arizona's
attainment demonstration and other elements required under the Clean
Air Act (CAA or ``Act''). The EPA is proposing to approve the base year
and projected emissions inventories and to affirm that the new source
review requirements for the area have been met. We are proposing to
disapprove the attainment demonstration, as well as other elements of
the plan tied to this demonstration, namely, the requirement for
meeting reasonable further progress (RFP) toward attainment of the
NAAQS, reasonably available control measures and reasonably available
control technology (RACM/RACT), enforceable emission limitations and
control measures, and contingency measures. We are taking comments on
this proposal and plan to follow with a final action.
DATES: Any comments on this proposal must be received by June 22, 2020.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R09-
OAR-2020-0109, at https://www.regulations.gov, or via email to Ashley
Graham, Air Planning Office at [email protected]. For comments
submitted at Regulations.gov, follow the online instructions for
submitting comments. Once submitted, comments cannot be removed or
edited from Regulations.gov. For either manner of submission, the EPA
may publish any comment received to its public docket. Do not submit
electronically any information you consider to be Confidential Business
Information (CBI) or other information whose disclosure is restricted
by statute. Multimedia submissions (e.g., audio or video) must be
accompanied by a written comment. The written comment is considered the
official comment and should include discussion of all points you wish
to make. The EPA will generally not consider comments or comment
contents located outside of the primary submission (i.e., on the web,
cloud, or other file sharing system). For additional submission
methods, please contact the person identified in the FOR FURTHER
INFORMATION CONTACT section. For the full EPA public comment policy,
information about CBI or multimedia submissions, and general guidance
on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.
FOR FURTHER INFORMATION CONTACT: Ashley Graham, EPA Region IX, Air
Division, Air Planning Office, (415) 972-3877, [email protected].
SUPPLEMENTARY INFORMATION: Throughout this document, the words ``we,''
``us,'' or ``our'' refer to the EPA.
Table of Contents
I. Why was Arizona required to submit a plan for the Hayden
SO2 nonattainment area?
II. Requirements for SO2 Nonattainment Plans
III. Attainment Demonstration and Longer-Term Averaging
IV. Review of Modeled Attainment Demonstration
A. Air Quality Modeling
B. Emission Limits
C. Summary of Results
V. Review of Other Plan Requirements
A. Emissions Inventory
B. Reasonably Available Control Measures and Reasonably
Available Control Technology
C. New Source Review
D. Reasonable Further Progress
E. Contingency Measures
VI. Conformity
VII. The EPA's Proposed Action
VIII. Statutory and Executive Order Reviews
I. Why was Arizona required to submit a plan for the Hayden
SO2 nonattainment area?
On June 22, 2010, the EPA promulgated a new 1-hour primary
SO2 NAAQS of 75 parts per billion (ppb). This standard is
met at an ambient air quality monitoring site when the 3-year average
of the annual 99th percentile of daily maximum 1-hour average
concentrations does not exceed 75 ppb, as determined in accordance with
appendix T of 40 CFR part 50.\1\ On August 5, 2013, the EPA designated
a first set of 29 areas of the country as nonattainment for the 2010
SO2 NAAQS, including the Hayden SO2 NAA within
Arizona.\2\ These area designations became effective on October 4,
2013. Section 191(a) of the CAA directs states to submit SIPs for areas
designated as nonattainment for the SO2 NAAQS to the EPA
within 18 months of the effective date of the designation, i.e., by no
later than April 4, 2015, in this case (hereinafter called ``plans'' or
``nonattainment plans''). Under CAA section 192(a), these plans are
required to have measures that will provide for attainment of the NAAQS
as expeditiously as practicable, but no later than five years from the
effective date of designation, i.e., October 4, 2018, for the Hayden
SO2 NAA.
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\1\ 75 FR 35520, codified at 40 CFR 50.17(a)-(b).
\2\ 78 FR 47191, codified at 40 CFR part 81, subpart C.
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For a number of areas, including the Hayden SO2 NAA, the
EPA published a document on March 18, 2016, finding that Arizona and
other pertinent states had failed to submit the required SO2
nonattainment plan by the submittal deadline.\3\ The finding became
effective on April 18, 2016, and initiated a deadline under CAA section
179(a) for the potential imposition of new source review offset and
highway funding sanctions. Additionally, under CAA section 110(c), the
finding triggered a requirement that the EPA promulgate a federal
implementation plan within two years of the effective date of the
finding unless by that time the state had made the necessary complete
submittal and the EPA had approved the submittal as meeting applicable
requirements.
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\3\ 81 FR 14736.
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In response to the requirement for SO2 nonattainment
plan submittals, the Arizona Department of Environmental Quality (ADEQ)
submitted the Hayden SO2 Plan on March 9, 2017, and
submitted associated final rules on April 6, 2017.\4\ The EPA issued
letters dated July 17, 2017, and September 26, 2017, finding the
submittals complete and halting the sanctions clock under CAA section
179(a).\5\
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\4\ Letters dated March 8, 2017, and April 6, 2017, from Timothy
S. Franquist, Director, Air Quality Division, ADEQ, to Alexis
Strauss, Acting Regional Administrator, EPA, Region IX. Although the
cover letter for the Hayden SO2 Plan was dated March 8,
2017, the Plan was transmitted to the EPA on March 9, 2017.
\5\ Letters dated July 17, 2017, and September 26, 2017, from
Elizabeth Adams, Director, Air Division, EPA, Region IX to Timothy
S. Franquist, Director, Air Quality Division, ADEQ.
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The remainder of this preamble describes the requirements that
nonattainment plans must meet in order to obtain EPA approval, provides
a review of the Hayden SO2 Plan with respect to these
requirements, and describes the EPA's proposed action on the Plan.
[[Page 31119]]
II. Requirements for SO2 Nonattainment Plans
Nonattainment plans for SO2 must meet the applicable
requirements of the CAA, specifically CAA sections 110, 172, 191, and
192. The EPA's regulations governing nonattainment SIP submissions are
set forth at 40 CFR part 51, with specific procedural requirements and
control strategy requirements residing at subparts F and G,
respectively. Soon after Congress enacted the 1990 Amendments to the
CAA, the EPA issued comprehensive guidance on SIP revisions in the
``General Preamble for the Implementation of Title I of the Clean Air
Act Amendments of 1990'' (``General Preamble'').\6\ Among other things,
the General Preamble addressed SO2 SIP submissions and
fundamental principles for SIP control strategies.\7\ On April 23,
2014, the EPA issued recommended guidance for meeting the statutory
requirements in SO2 SIP submissions, in a document entitled,
``Guidance for 1-Hour SO2 Nonattainment Area SIP
Submissions'' (``2014 SO2 Guidance''). In the 2014
SO2 Guidance, the EPA described the statutory requirements
for a complete nonattainment plan, including: an accurate emissions
inventory of current emissions for all sources of SO2 within
the NAA; an attainment demonstration; a demonstration of RFP;
implementation of RACM (including RACT); new source review; enforceable
emission limitations and control measures; and adequate contingency
measures for the affected area.
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\6\ 57 FR 13498 (April 16, 1992).
\7\ Id. at 13548-13549, 13567-13568.
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For the EPA to fully approve a SIP revision as meeting the
requirements of CAA sections 110, 172, 191, and 192, and the EPA's
regulations at 40 CFR part 51, the plan for the affected area needs to
demonstrate to the EPA's satisfaction that each of the aforementioned
requirements has been met. Under CAA section 110(l), the EPA may not
approve a plan that would interfere with any applicable requirement
concerning NAAQS attainment and RFP, or any other applicable
requirement. Under CAA section 193, no requirement in effect (or
required to be adopted by an order, settlement, agreement, or plan in
effect before November 15, 1990) in any area that is nonattainment for
any air pollutant may be modified in any manner unless it ensures
equivalent or greater emission reductions of such air pollutant.
III. Attainment Demonstration and Longer-Term Averaging
Sections 172(c)(1) and 172(c)(6) of the CAA direct states with
areas designated as nonattainment to demonstrate that the submitted
plan provides for attainment of the NAAQS. 40 CFR part 51, subpart G
further delineates the control strategy requirements that plans must
meet, and the EPA has long required that all SIPs and control
strategies reflect four fundamental principles of quantification,
enforceability, replicability, and accountability.\8\ SO2
nonattainment plans must consist of two components: (1) Emission limits
and other control measures that assure implementation of permanent,
enforceable, and necessary emission controls, and (2) a modeling
analysis that meets the requirements of 40 CFR part 51, appendix W and
demonstrates that these emission limits and control measures provide
for timely attainment of the primary SO2 NAAQS as
expeditiously as practicable, but no later than the attainment date for
the affected area. In cases where the necessary emission limits have
not previously been made a part of the state's SIP or have not
otherwise become federally enforceable, the plan needs to include the
necessary enforceable limits in an adopted form suitable for
incorporation into the SIP in order for the plan to be approved by the
EPA. In all cases, the emission limits and control measures must be
accompanied by appropriate methods and conditions to determine
compliance with the respective emission limits and control measures and
must be quantifiable (i.e., a specific amount of emission reduction can
be ascribed to the measures), fully enforceable (i.e., specifying
clear, unambiguous and measurable requirements for which compliance can
be practicably determined), replicable (i.e., the procedures for
determining compliance are sufficiently specific and non-subjective so
that two independent entities applying the procedures would obtain the
same result), and accountable (i.e., source specific limits must be
permanent and must reflect the assumptions used in the SIP
demonstrations).
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\8\ Id. at 13567-13568.
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The EPA's 2014 SO2 Guidance recommends that the emission
limits be expressed as short-term average limits not to exceed the
averaging time for the applicable NAAQS that the limit is intended to
help maintain (e.g., addressing emissions averaged over one or three
hours), but it also describes the option to utilize emission limits
with longer averaging times of up to 30 days as long as the state meets
various suggested criteria.\9\ The 2014 SO2 Guidance
recommends that, should states and sources utilize longer averaging
times (such as 30 days), the longer-term average limit should be set at
an adjusted level that reflects a stringency comparable to the 1-hour
average limit at the critical emission value shown to provide for
attainment.
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\9\ 2014 SO2 Guidance, 22-39.
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The 2014 SO2 Guidance provides an extensive discussion
of the EPA's rationale for concluding that appropriately set,
comparable stringent limitations based on averaging times as long as 30
days can be found to provide for attainment of the 2010 SO2
NAAQS. In evaluating this option, the EPA considered the nature of the
standard, conducted detailed analyses of the impact of use of 30-day
average limits on the prospects for attaining the standard, and
carefully reviewed how best to achieve an appropriate balance among the
various factors that warrant consideration in judging whether a state's
plan provides for attainment.\10\
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\10\ Id. at 22-39, appendices B and D.
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Preferred air quality models for use in regulatory applications are
described in appendix A of the EPA's ``Guideline on Air Quality
Models'' (40 CFR part 51, appendix W (``appendix W'')).\11\ In general,
nonattainment SIP submissions must demonstrate the adequacy of the
selected control strategy using the applicable air quality model
designated in appendix W.\12\ However, where an air quality model
specified in appendix W is inappropriate for the particular
application, the model may be modified or another model substituted, if
the EPA approves the modification or substitution.\13\ In 2005, the EPA
promulgated the American Meteorological Society/Environmental
Protection Agency Regulatory Model (AERMOD) as the Agency's preferred
near-field dispersion model for a wide range of regulatory applications
addressing stationary sources (e.g., in estimating SO2
concentrations) in all types of terrain based on an extensive
developmental and performance evaluation. Supplemental guidance on
modeling for purposes of demonstrating attainment of the SO2
standard is provided in appendix A of the 2014 SO2 Guidance.
Appendix A provides extensive guidance on the modeling domain, the
source inputs, assorted types of meteorological data, and
[[Page 31120]]
background concentrations. Consistency with the recommendations in the
2014 SO2 Guidance is generally necessary for the attainment
demonstration to offer adequately reliable assurance that the plan
provides for attainment.
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\11\ The EPA published revisions to appendix W on January 17,
2017, 82 FR 5182.
\12\ 40 CFR 51.112(a)(1).
\13\ 40 CFR 51.112(a)(2); appendix W, section 3.2.
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As stated previously, attainment demonstrations for the 2010 1-hour
primary SO2 NAAQS must demonstrate future attainment and
maintenance of the NAAQS in the entire area designated as nonattainment
(i.e., not just at the violating monitor) by using air quality
dispersion modeling (see appendix W) to show that the mix of sources
and enforceable control measures and emission rates in an identified
area will not lead to a violation of the SO2 NAAQS. For the
short-term (i.e., 1-hour) standard, the EPA believes that dispersion
modeling, using allowable emissions and addressing stationary sources
in the affected area (and in some cases those sources located outside
the NAA that may affect attainment in the area) is technically
appropriate. This approach is also efficient and effective in
demonstrating attainment in NAAs because it takes into consideration
combinations of meteorological and source operating conditions that may
contribute to peak ground-level concentrations of SO2.
The meteorological data used in the analysis should generally be
processed with the most recent version of AERMET, which is the
meteorological data preprocessor for AERMOD. Estimated concentrations
should include ambient background concentrations, follow the form of
the standard, and be calculated as described in the EPA's August 23,
2010 clarification memorandum.\14\
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\14\ ``Applicability of Appendix W Modeling Guidance for the 1-
hr SO2 National Ambient Air Quality Standard'' (August
23, 2010).
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IV. Review of Modeled Attainment Demonstration
A. Air Quality Modeling
ADEQ's attainment demonstration used AERMOD version 15181, the
regulatory version at the time it conducted its nonattainment planning.
As input to AERMOD, ADEQ used one year of on-site surface
meteorological data collected by ASARCO \15\ LLC (``Asarco'') between
August 16, 2013, through August 15, 2014, at a 10-meter tower located
approximately 0.35 kilometers south of the smelter building. After
submittal, ADEQ discovered an error in the processing of the on-site
surface meteorological data. Correcting this error changed predicted
SO2 concentrations such that the modeling no longer shows
attainment of the 2010 SO2 NAAQS. ADEQ has been working with
Asarco and the EPA on revised modeling and intends to submit a new
attainment demonstration and revised emission limits at a future
date.\16\
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\15\ ASARCO was organized in 1899 as the American Smelting And
Refining COmpany.
\16\ Email dated March 25, 2020, from Farah Esmaeili, ADEQ to
Rynda Kay, EPA Region IX.
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B. Emission Limits
An important prerequisite for approval of a nonattainment plan is
the inclusion of ``enforceable emission limitations . . . as may be
necessary or appropriate to provide for attainment of such standard in
such area by the applicable attainment date . . . .''\17\ The emission
limits that were intended to provide for attainment of the 2010
SO2 NAAQS for the Hayden area are codified in the Arizona
Administrative Code (AAC), Title 18, Chapter 2, Article 13, Section
R18-2-B1302 (``Rule B1302''). ADEQ submitted Rule B1302 to the EPA on
March 3, 2017. In a separate action, the EPA is proposing a limited
approval and limited disapproval of Rule B1302. We are proposing a
limited approval because the rule includes a more stringent
SO2 emission limit for the main stack at the Hayden Smelter
compared to the existing SIP-approved limit, as well as operational
standards and monitoring, recordkeeping and reporting requirements that
strengthen the SIP. At the same time, we are proposing a limited
disapproval because of deficiencies in the rule's enforceability. Of
particular relevance to the Hayden SO2 Plan, Rule B1302 does
not contain any numeric fugitive emission limits or ongoing monitoring
requirements corresponding to the levels of fugitive emissions that
were modeled in the Plan. Instead, the rule relies on requirements in
an operations and maintenance plan and two year-long fugitive emissions
studies to verify compliance with the modeled fugitive emissions. While
the fugitive emissions studies will provide useful information to
verify the nature and extent of fugitive emissions from the facility,
this approach does not satisfy the requirements for enforceable limits
that provide for attainment of the SO2 NAAQS under CAA
section 172(c)(6).
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\17\ CAA section 172(c)(6). See also 57 FR 13498, 13567-13568
(emission limits that provide for attainment be quantifiable, fully
enforceable, replicable, and accountable).
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In addition, Rule B1302 has several other deficiencies that
undermine its enforceability in certain circumstances:
Rule subsection (E)(4) provides an option for alternative
sampling points that could undermine the enforceability of the stack
emission limit by providing undue flexibility to change sampling points
without undergoing a SIP revision.
Rule subsection (E)(6) allows for nearly 10 percent of
total facility SO2 emissions annually to be exempt from
continuous emissions monitoring systems; this deficiency could
compromise the enforceability of the main stack emission limit.
The rule lacks a method for measuring or calculating
emissions from a shutdown ventilation flue; this omission could
compromise the enforceability of the main stack emission limit.
The rule lacks a method for calculating hourly
SO2 emissions; this omission makes it is unclear what
constitutes a ``valid hour'' for purposes of allowing data
substitution.\18\
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\18\ Rule B1302, subsection (F)(2) contains a procedure for
substituting emissions data for compliance demonstration purposes
``when no valid hour or hours of data have been recorded by a
continuous monitoring system.'' In the absence of a method for
calculating hourly emissions, it is unclear when this procedure is
to be used.
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In light of these deficiencies, we propose to find that the Hayden
SO2 Plan does not include emissions limits necessary to
provide for attainment of the SO2 NAAQS.
Finally, we note that the main stack emission limit in Rule B1302
takes the form of a ``dual limit,'' under which ``[e]missions from the
Main Stack shall not exceed 1069.1 pounds per hour on a 14-operating
day average unless 1,518 pounds or less is emitted during each hour of
the 14-operating day period.'' \19\ This dual limit is intended to
provide a level of stringency comparable to a one-hour limit of 1,518
pounds per hour. Because we are proposing to find (1) that ADEQ has not
demonstrated the emission limits in Rule B1302 are sufficient to
provide for attainment and (2) that the stack emission limit is not
fully enforceable due to various deficiencies in Rule B1302, we have
not evaluated whether the dual limit is of comparable stringency to a
simple one-hour limit of 1,518 pounds per hour.
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\19\ Rule B1302, subsection (C)(1).
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C. Summary of Results
The EPA has reviewed ADEQ's submitted modeling supporting the
attainment demonstration for the Hayden SO2 NAA and has
preliminarily determined that this modeling is inconsistent with CAA
requirements, appendix W, and the 2014 SO2 Guidance due to
an error in the meteorological fields used. Without accurate modeling
we are unable to
[[Page 31121]]
determine that the emission limits are sufficient for the Hayden
SO2 NAA to attain the 2010 SO2 NAAQS.
Furthermore, Rule B1302 does not include a numeric fugitive emissions
limit and has other deficiencies related to the enforceability of the
main stack emission limit. Therefore, we are proposing to disapprove
the attainment demonstration in the Hayden SO2 Plan pursuant
to 172(c) and 192(a).
V. Review of Other Plan Requirements
A. Emissions Inventory
The emissions inventory and source emission rate data for an area
serve as the foundation for air quality modeling and other analyses
that enable states to estimate the degree to which different sources
within a NAA contribute to violations within the affected area and
assess the expected improvement in air quality within the NAA due to
the adoption and implementation of control measures. The state must
develop and submit to the EPA a comprehensive, accurate, and current
inventory of actual emissions from all sources of SO2
emissions in each NAA, as well as any sources located outside the NAA
that may affect attainment in the area.\20\
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\20\ CAA section 172(c)(3).
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The base year inventory establishes a baseline that is used to
evaluate emission reductions achieved by the control strategy and to
assess RFP requirements. ADEQ used 2011 as the base year for emissions
inventory preparation. At the time of preparation of the Plan, 2011
reflected the most recent triennial National Emission Inventory,
supported the requirement for timeliness of data, and was also
representative of a year with violations of the primary SO2
NAAQS. ADEQ reviewed and compiled actual emissions of all sources of
SO2 in the NAA in the 2011 base year emissions inventory. In
addition to developing an emissions inventory of SO2
emission sources within the NAA, ADEQ also provided an SO2
emissions inventory for those emission sources within a 50 kilometer
buffer zone of the NAA. Table 1 summarizes 2011 base year
SO2 emissions inventory data for the NAA, categorized by
emission source type (rounded to the nearest whole number).
Table 1--Base Year SO2 Emissions Inventory for the Hayden SO2 NAA
[Tons per year]
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Year Point Nonpoint On-road mobile Non-road mobile Total
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2011............................................................... 21,771 6 <1 2 21,779
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Source: Hayden SO2 Plan, Table 3-10.
As shown in Table 1, the majority of SO2 emissions in
the 2011 base year inventory can be attributed to the point source
category. Emissions for this category are provided in further detail in
Table 2.
Table 2--Base Year Point Source SO2 Emissions Inventory
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Emissions
Point source (Tons per
year)
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Asarco LLC Hayden Smelter............................... 21,747
Asarco Ray Mine Complex................................. 24
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Total............................................... 21,771
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Source: Hayden SO2 Plan, Table 3-3.
A projected attainment year emissions inventory should also be
included in the SIP submission according to the 2014 SO2
Guidance. This emissions inventory should include, in a manner
consistent with the attainment demonstration, estimated emissions for
all SO2 emission sources that were determined to have an
impact on the affected NAA for the projected attainment year. Table 3
summarizes Arizona's projected 2018 SO2 emissions inventory
data for the NAA, categorized by source type. The 2011 base year
emissions, as well as the projected change between base year and
projected year emissions, are also summarized (rounded to the nearest
whole number).
Table 3--Projected 2018 Emissions Inventory for the Hayden SO2 NAA
[Tons per year]
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Non-road
Year Point Nonpoint On-road mobile mobile Total
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2011............................ 21,771 6 <1 2 21,779
2018............................ 7,968 6 <1 <1 7,973
Change.......................... -13,803 0 0 -2 -13,806
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Source: Hayden SO2 Plan, Table 3-16.
As shown in Table 3, both the majority of SO2 emissions
in the projected 2018 emission inventory, as well as the majority of
projected SO2 emission reductions, can be attributed to
point sources. Emissions for this category were determined based on a
potential to emit at 100 percent load capacity or federally enforceable
permit
[[Page 31122]]
limits and are provided in further detail in Table 4. The single
largest decrease in emissions is attributed to the Hayden Smelter.
Table 4--Projected 2018 Point Source Emissions Inventory
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2018
2011 Base year Projected year
Point source emissions emissions Change
(tons per (tons per
year) year)
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Asarco LLC Hayden Smelter....................................... 21,747 a 7,852 -13,895
Asarco Ray Mine Complex......................................... 24 116 92
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Total....................................................... 21,771 7,968 -13,803
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Source: Hayden SO2 Plan, Table 3-11.
a Because Asarco was required to shut down five existing converters by May 2018, the 2018-projected emissions
reflect a partial year of controls. Controls were required be fully implemented prior to 2019, during which
emissions were projected to be 2,320 tons.
The EPA has evaluated ADEQ's 2011 base year inventory and projected
2018 emissions inventory for the Hayden SO2 NAA and finds
these inventories and the methodologies used for their development to
be consistent with EPA guidance. As a result, the EPA is proposing to
determine that the Hayden SO2 Plan meets the requirements of
CAA section 172(c)(3) and (4) for the Hayden SO2 NAA.
B. Reasonably Available Control Measures and Reasonably Available
Control Technology
ADEQ's Plan for attaining the 1-hour SO2 NAAQS in the
Hayden SO2 NAA is based on implementation of controls at the
Hayden Smelter. These controls include the replacement of the existing
five converter units with three larger units, installation of more
extensive, efficient, and effective fugitive gas control ducting around
the converters, and the installation of additional process gas controls
before venting to the main stack. These controls are collectively
referred to as the ``Converter Retrofit Project.'' ADEQ conducted a
RACM/RACT analysis in the Hayden SO2 Plan, comparing the
requirements at the Hayden Smelter with controls in use at other large
sources of SO2 to identify potentially available control
measures and eliminating any measures that were not feasible at the
Hayden Smelter or not more stringent than those measures already being
implemented. ADEQ then compared the proposed control measures for the
Hayden Smelter with the measures not eliminated in the first step of
the RACM/RACT analysis and concluded that the proposed control measures
would be more stringent. Our assessment of ADEQ's RACM/RACT analysis
follows.
The State's RACM/RACT analysis can be found in section 4.4.3 of the
Hayden SO2 Plan. ADEQ compared SO2 controls at
eight different facilities and found that all these units use an acid
plant to recover or reduce SO2 emissions. Some of these
facilities also use acid absorption equipment (wet and dry scrubbers)
to further control emissions of SO2.
ADEQ concluded that the Hayden Smelter's use of an acid plant, the
Converter Retrofit Project, and dry lime scrubbing are comparable to
SO2 control measures employed by similar sources. ADEQ
reviewed the EPA's RACT/BACT/LAER Clearinghouse and air permits for
facilities likely to have analogous processes as provided by the Air &
Waste Management Association and determined that the Converter Retrofit
Project controls for the Hayden Smelter are representative of RACM/RACT
level of control.
As explained in section IV of this document, we find that ADEQ has
not demonstrated that implementation of the control measures required
under the Plan is sufficient to provide for attainment of the NAAQS in
the Hayden SO2 NAA because the modeling submitted with the
attainment plan is flawed. As explained in the General Preamble,
``control technology which failed to achieve the SO2 NAAQS
would, by definition, fail to be SO2 RACT.'' \21\ Given that
RACT is a necessary component of RACM under CAA section 172(c)(1), we
propose to conclude that the State has not satisfied the requirement in
CAA section 172(c)(1) to adopt and submit all RACM/RACT as needed to
attain the standard as expeditiously as practicable.
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\21\ 57 FR 13498, 13547.
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C. New Source Review
On November 2, 2015, the EPA published a final limited approval and
limited disapproval of revisions to ADEQ's new source review (NSR)
rules.\22\ On May 4, 2018, the EPA approved additional rule revisions
to address many of the deficiencies identified in the 2015 action.\23\
Collectively, these rule revisions ensure that ADEQ's rules provide for
appropriate NSR for SO2 sources undergoing construction or
major modification in the Hayden SO2 NAA without need for
further modification. Therefore, the EPA has already concluded that the
NSR requirement has been met for this area, and we are not reopening
that determination in this proposed action. We note that Rule B1302
subsection (I) (Preconstruction review) indicates that the smelter
emission limits contained in the rule shall be determined to be
SO2 RACT for purposes of minor NSR requirements. This
provision does not interfere with or adversely affect existing
nonattainment NSR rules.
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\22\ 80 FR 67319.
\23\ 83 FR 19631.
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D. Reasonable Further Progress
In the Hayden SO2 Plan, Arizona explained its rationale
for concluding that the Plan meets the requirement for RFP in
accordance with EPA guidance. Specifically, ADEQ's rationale is based
on EPA guidance interpreting the RFP requirement being satisfied for
SO2 if the Plan requires ``adherence to an ambitious
compliance schedule'' that ``implement[s] appropriate control measures
as expeditiously as practicable.'' ADEQ noted that its Plan provides
for attainment as expeditiously as practicable, i.e., by October 4,
2018, and finds that the Plan thereby satisfies the requirement for
RFP.
ADEQ finds that the Hayden SO2 Plan requires affected
sources to implement appropriate control measures as expeditiously as
practicable to ensure attainment of the standard by the applicable
attainment date. ADEQ concludes that the Plan provides for RFP in
accordance with the approach to RFP described in the 2014
SO2 Guidance.
[[Page 31123]]
We note that the EPA's policy indicating RFP for SO2 may
be satisfied by ``adherence to an ambitious compliance schedule'' is
based on the fact that, ``for SO2 there is usually a single
`step' between pre-control nonattainment and post-control attainment.''
\24\ In this instance, however, ADEQ has not demonstrated that
implementation of the control measures required under the Plan is
sufficient to provide for attainment of the NAAQS in the Hayden
SO2 NAA. In the absence of a demonstration that the required
controls will lead to attainment, a compliance schedule to implement
these controls is not sufficient to provide for RFP. Therefore, we
propose to conclude that the State has not satisfied the requirement in
section 172(c)(2) to provide for RFP toward attainment in the Hayden
SO2 NAA.
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\24\ 2014 SO2 Guidance, 40.
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E. Contingency Measures
In the Hayden SO2 Plan, ADEQ explained its rationale for
concluding that the Plan meets the requirement for contingency
measures. Specifically, ADEQ relies on the 2014 SO2
Guidance, which notes the special circumstances that apply to
SO2 and explains on that basis why the contingency
requirement in CAA section 172(c)(9) is met for SO2 by
having a comprehensive program to identify sources of violations of the
SO2 NAAQS and to undertake an aggressive follow-up for
compliance and enforcement of applicable emission limitations. ADEQ
stated that it has such an enforcement program pursuant to state law in
Arizona Revised Statutes (ARS) sections 49-461, 49-402, 49-404, and 49-
406. ADEQ also describes the process under state law to apply
contingency measures for failure to make RFP and/or for failure to
attain the SO2 NAAQS by the attainment date and concludes
that ADEQ's Plan satisfies contingency measure requirements.
We note that the EPA has approved ARS 49-402, 49-404, 49-406, and
49-461 into the Arizona SIP.\25\ In addition, we have approved ARS 49-
422(A) (``Powers and Duties''), which authorizes ADEQ to require
sources of air contaminants to ``monitor, sample or perform other
studies to quantify emissions of air contaminants or levels of air
pollution that may reasonably be attributable to that source'' for
purposes of determining whether the source is in violation of a control
requirement. We have also approved ARS 49-460 through 49-463, which
authorize ADEQ to request compliance-related information from sources,
to issue orders of abatement upon reasonable cause to believe a source
has violated or is violating an air pollution control requirement, to
establish injunctive relief, to establish civil penalties of up to
$10,000 per day per violation, and to conduct criminal enforcement, as
appropriate, through the Attorney General.\26\ Therefore, we agree that
the Arizona SIP establishes a comprehensive enforcement program,
allowing for the identification of sources of SO2 NAAQS
violations and aggressive compliance and enforcement follow-up.
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\25\ 40 CFR 52.120(e), Table 3.
\26\ 77 FR 66398 (November 5, 2012).
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However, the EPA's policy that a comprehensive enforcement program
can satisfy the contingency measures requirement is premised on the
idea that full compliance with the controls required in the plan will
assure attainment. In this case, as explained above, ADEQ has not
demonstrated that implementation of the control measures required under
the Plan is adequate to provide for RFP and attainment of the NAAQS in
the Hayden SO2 NAA. Accordingly, there is no evidence that a
program to enforce these controls would be sufficient to bring the area
into attainment in the event of NAAQS violations after the attainment
date. Furthermore, the enforceability of these control measures is
undermined by the deficiencies in Rule B1302 described in section IV.B.
Therefore, we propose to conclude that the State has not satisfied the
requirement in section 172(c)(9) to provide for contingency measures to
be undertaken if the area fails to make RFP or to attain NAAQS by the
attainment date.
VI. Conformity
Generally, as set forth in section 176(c) of the CAA, conformity
requires that actions by federal agencies do not cause new air quality
violations, worsen existing violations, or delay timely attainment of
the relevant NAAQS. General conformity applies to federal actions,
other than certain highway and transportation projects, if the action
takes place in a NAA or maintenance area (i.e., an area which submitted
a maintenance plan that meets the requirements of section 175A of the
CAA and has been redesignated to attainment) for ozone, particulate
matter, nitrogen dioxide, carbon monoxide, lead, or SO2. The
EPA's General Conformity Rule establishes the criteria and procedures
for determining if a federal action conforms to the SIP.\27\ With
respect to the 2010 SO2 NAAQS, federal agencies are expected
to continue to estimate emissions for conformity analyses in the same
manner as they estimated emissions for conformity analyses under the
previous NAAQS for SO2. The EPA's General Conformity Rule
includes the basic requirement that a federal agency's general
conformity analysis be based on the latest and most accurate emission
estimation techniques available.\28\ When updated and improved emission
estimation techniques become available, the EPA expects the federal
agency to use these techniques.
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\27\ 40 CFR 93.150 to 93.165.
\28\ 40 CFR 93.159(b).
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Transportation conformity determinations are not required in
SO2 nonattainment and maintenance areas. The EPA concluded
in its 1993 transportation conformity rule that highway and transit
vehicles are not significant sources of SO2. Therefore,
transportation plans, transportation improvement programs, and projects
are presumed to conform to applicable implementation plans for
SO2.\29\
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\29\ 58 FR 3768, 3776 (January 11, 1993).
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VII. The EPA's Proposed Action
The EPA is proposing to partially approve and partially disapprove
portions of the Hayden SO2 Plan, which includes ADEQ's
attainment demonstration for the Hayden SO2 NAA and
addresses requirements for RFP, RACM/RACT, base year and projected
emissions inventories, new source review, and contingency measures. The
EPA proposes to determine that the Hayden SO2 Plan meets the
emissions inventory requirements under CAA section 172(c)(3) and (4)
and to affirm that the State has met the new source review requirements
for the Hayden SO2 NAA under section 172(c)(5). We propose
to determine that the Hayden SO2 Plan does not meet the
attainment demonstration, RACM/RACT, enforceable emission limitations,
RFP, or contingency measure requirements of the CAA for the 2010
SO2 NAAQS. Final partial disapproval of the Hayden
SO2 Plan would trigger sanctions under CAA section 179 and
40 CFR 52.31 unless the EPA determines that Arizona has corrected the
deficiencies within 18 months of the effective date of the final
action.
The EPA is taking public comments for 30 days following the
publication of this proposed action in the Federal Register. We will
take all relevant timely comments into consideration in our final
action.
[[Page 31124]]
VIII. Statutory and Executive Order Reviews
Additional information about these statutes and Executive Orders
can be found at http://www2.epa.gov/laws-regulations/laws-and-executive-orders.
A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review
This action is not a significant regulatory action and was
therefore not submitted to the Office of Management and Budget (OMB)
for review.
B. Executive Order 13771: Reducing Regulations and Controlling
Regulatory Costs
This action is not expected to be an Executive Order 13771
regulatory action because this action is not significant under
Executive Order 12866.
C. Paperwork Reduction Act (PRA)
This action does not impose an information collection burden under
the PRA because this action does not impose additional requirements
beyond those imposed by state law.
D. Regulatory Flexibility Act (RFA)
I certify that this action will not have a significant economic
impact on a substantial number of small entities under the RFA. This
action will not impose any requirements on small entities beyond those
imposed by state law.
E. Unfunded Mandates Reform Act (UMRA)
This action does not contain any unfunded mandate as described in
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect
small governments. This action does not impose additional requirements
beyond those imposed by state law. Accordingly, no additional costs to
state, local, or tribal governments, or to the private sector, will
result from this action.
F. Executive Order 13132: Federalism
This action does not have federalism implications. It will not have
substantial direct effects on the states, on the relationship between
the national government and the states, or on the distribution of power
and responsibilities among the various levels of government.
G. Executive Order 13175: Coordination With Indian Tribal Governments
This action does not have tribal implications, as specified in
Executive Order 13175, because the SIP is not approved to apply on any
Indian reservation land or in any other area where the EPA or an Indian
tribe has demonstrated that a tribe has jurisdiction, and will not
impose substantial direct costs on tribal governments or preempt tribal
law. Thus, Executive Order 13175 does not apply to this action.
H. Executive Order 13045: Protection of Children From Environmental
Health Risks and Safety Risks
The EPA interprets Executive Order 13045 as applying only to those
regulatory actions that concern environmental health or safety risks
that the EPA has reason to believe may disproportionately affect
children, per the definition of ``covered regulatory action'' in
section 2-202 of the Executive Order. This action is not subject to
Executive Order 13045 because it does not impose additional
requirements beyond those imposed by state law.
I. Executive Order 13211: Actions That Significantly Affect Energy
Supply, Distribution, or Use
This action is not subject to Executive Order 13211, because it is
not a significant regulatory action under Executive Order 12866.
J. National Technology Transfer and Advancement Act (NTTAA)
Section 12(d) of the NTTAA directs the EPA to use voluntary
consensus standards in its regulatory activities unless to do so would
be inconsistent with applicable law or otherwise impractical. The EPA
believes that this action is not subject to the requirements of section
12(d) of the NTTAA because application of those requirements would be
inconsistent with the CAA.
K. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Population
The EPA lacks the discretionary authority to address environmental
justice in this rulemaking.
List of Subjects in 40 CFR Part 52
Environmental protection, Air pollution control, Incorporation by
reference, Intergovernmental relations, Nitrogen dioxide, Particulate
matter, Reporting and recordkeeping requirements, Sulfur dioxide,
Volatile organic compounds.
Authority: 42 U.S.C. 7401 et seq.
Dated: May 12, 2020.
John Busterud,
Regional Administrator, Region IX.
[FR Doc. 2020-10586 Filed 5-21-20; 8:45 am]
BILLING CODE 6560-50-P