Proposed Rule2024-11807
Partial Approval and Disapproval of Air Quality Implementation Plans; Arizona; Regional Haze State Implementation Plan for the Second Implementation Period and Prong 4 (Visibility) for the 2015 Ozone and 2012 Particulate Matter Standards
Primary source
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Published
May 31, 2024
Issuing agencies
Environmental Protection Agency
Abstract
The Environmental Protection Agency (EPA) is proposing to partially approve and partially disapprove the regional haze state implementation plan (SIP) revision submitted by Arizona on August 15, 2022 ("2022 Arizona Regional Haze Plan"), under the Clean Air Act (CAA) and the EPA's Regional Haze Rule for the program's second implementation period. Arizona's SIP submission addresses the requirement that states must periodically revise their long-term strategies for making reasonable progress towards the national goal of preventing any future, and remedying any existing, anthropogenic impairment of visibility, including regional haze, in mandatory Class I Federal areas. The SIP submission also addresses other applicable requirements for the second implementation period of the regional haze program. Within this action, the EPA is also proposing to disapprove the visibility transport prong of Arizona's infrastructure SIP submittals for the 2012 annual fine particulate matter (PM<INF>2.5</INF>) and 2015 ozone National Ambient Air Quality Standards (NAAQS). The EPA is taking this action pursuant to CAA sections 110 and 169A.
Full Text
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[Federal Register Volume 89, Number 106 (Friday, May 31, 2024)]
[Proposed Rules]
[Pages 47398-47438]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2024-11807]
[[Page 47397]]
Vol. 89
Friday,
No. 106
May 31, 2024
Part III
Environmental Protection Agency
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40 CFR Part 52
Partial Approval and Disapproval of Air Quality Implementation Plans;
Arizona; Regional Haze State Implementation Plan for the Second
Implementation Period and Prong 4 (Visibility) for the 2015 Ozone and
2012 Particulate Matter Standards; Proposed Rule
Federal Register / Vol. 89 , No. 106 / Friday, May 31, 2024 /
Proposed Rules
[[Page 47398]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[EPA-R09-OAR-2024-0005; FRL-11919-01-R9]
Partial Approval and Disapproval of Air Quality Implementation
Plans; Arizona; Regional Haze State Implementation Plan for the Second
Implementation Period and Prong 4 (Visibility) for the 2015 Ozone and
2012 Particulate Matter Standards
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 the regional haze state
implementation plan (SIP) revision submitted by Arizona on August 15,
2022 (``2022 Arizona Regional Haze Plan''), under the Clean Air Act
(CAA) and the EPA's Regional Haze Rule for the program's second
implementation period. Arizona's SIP submission addresses the
requirement that states must periodically revise their long-term
strategies for making reasonable progress towards the national goal of
preventing any future, and remedying any existing, anthropogenic
impairment of visibility, including regional haze, in mandatory Class I
Federal areas. The SIP submission also addresses other applicable
requirements for the second implementation period of the regional haze
program. Within this action, the EPA is also proposing to disapprove
the visibility transport prong of Arizona's infrastructure SIP
submittals for the 2012 annual fine particulate matter
(PM<INF>2.5</INF>) and 2015 ozone National Ambient Air Quality
Standards (NAAQS). The EPA is taking this action pursuant to CAA
sections 110 and 169A.
DATES: Written comments must be received on or before July 1, 2024.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R09-
OAR-2024-0005 at <a href="https://www.regulations.gov">https://www.regulations.gov</a>. For comments submitted at
<a href="http://Regulations.gov">Regulations.gov</a>, follow the online instructions for submitting
comments. Once submitted, comments cannot be edited or removed from
<a href="http://Regulations.gov">Regulations.gov</a>. 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 (audio,
video, etc.) 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 <a href="https://www.epa.gov/dockets/commenting-epa-dockets">https://www.epa.gov/dockets/commenting-epa-dockets</a>. If you need assistance in a
language other than English or if you are a person with a disability
who needs a reasonable accommodation at no cost to you, please contact
the person identified in the FOR FURTHER INFORMATION CONTACT section.
FOR FURTHER INFORMATION CONTACT: Khoi Nguyen, Geographic Strategies &
Modeling Section (AIR-2-2), Planning & Analysis Branch, EPA Region IX,
75 Hawthorne Street, San Francisco, CA 94105, (415) 947-4120, or by
email at <a href="/cdn-cgi/l/email-protection#1f71786a667a7131747770765f7a6f7e31787069"><span class="__cf_email__" data-cfemail="bdd3dac8c4d8d393d6d5d2d4fdd8cddc93dad2cb">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION: Throughout this document, ``we,'' ``us,''
and ``our'' refer to the EPA.
Table of Contents
I. What action is the EPA proposing for regional haze?
II. Background and Requirements for Regional Haze Plans
A. Regional Haze Background
B. Roles of Agencies in Addressing Regional Haze
III. Requirements for Regional Haze Plans for the Second
Implementation Period
A. Identification of Class I Areas
B. Calculations of Baseline, Current, and Natural Visibility
Conditions; Progress to Date; and the Uniform Rate of Progress
C. Long-Term Strategy for Regional Haze
D. Reasonable Progress Goals
E. Monitoring Strategy and Other State Implementation Plan
Requirements
F. Requirements for Periodic Reports Describing Progress Towards
the Reasonable Progress Goals
G. Requirements for State and Federal Land Manager Coordination
IV. The EPA's Evaluation of Arizona's Regional Haze Submission for
the Second Implementation Period
A. Background on Arizona's First Implementation Period SIP
Submission
B. Overview of Arizona's Second Implementation Period SIP
Submission
C. Identification of Class I Areas
D. Calculations of Baseline, Current, and Natural Visibility
Conditions; Progress to Date; and the Uniform Rate of Progress
E. Long-Term Strategy for Regional Haze
1. Arizona's Long-Term Strategy in the 2022 Arizona Regional
Haze Plan
2. The EPA's Evaluation of Arizona's Long-Term Strategy
F. Reasonable Progress Goals
G. Additional Monitoring To Assess Reasonably Attributable
Visibility Impairment
H. Monitoring Strategy and Other Implementation Plan
Requirements
I. Requirements for Periodic Reports Describing Progress Towards
the Reasonable Progress Goals
J. Requirements for State and Federal Land Manager Coordination
V. Prong 4 (Visibility) of the 2012 PM<INF>2.5</INF> NAAQS and 2015
Ozone NAAQS Infrastructure SIPs
A. Infrastructure SIPs
B. Prong 4 Requirements
1. 2012 PM<INF>2.5</INF> NAAQS
2. 2015 Ozone NAAQS
C. Arizona's Prong 4 Elements
D. The EPA's Evaluation of Arizona's Submittal
VI. Proposed Action
VII. Statutory and Executive Order Reviews
I. What action is the EPA proposing for regional haze?
On August 15, 2022,\1\ the Arizona Department of Environmental
Quality (ADEQ) submitted the 2022 Arizona Regional Haze Plan. ADEQ
supplemented its SIP revision on August 25, 2023, with nonpoint source
rules (``2023 Arizona Regional Haze Rules Supplement'').\2\ ADEQ made
these SIP submissions to satisfy requirements of the CAA's regional
haze program pursuant to CAA sections 169A and 169B and 40 CFR 51.308.
The EPA is proposing to partially approve and partially disapprove the
2022 Arizona Regional Haze Plan. For the reasons described in this
document, the EPA is proposing to approve the elements of the 2022
Arizona Regional Haze Plan related to requirements contained in 40 CFR
51.308(f)(1), (f)(4)-(6), and (g)(1)-(5). The EPA is proposing to
disapprove the elements of the 2022 Arizona Regional Haze Plan related
to requirements contained in 40 CFR 51.308(f)(2), (f)(3), and (i)(2)-
(4). We are
[[Page 47399]]
not proposing to act on the 2023 Arizona Regional Haze Rules Supplement
at this time.
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\1\ Letter dated August 15, 2022, from Daniel Czecholinski,
Director, Arizona Department of Environmental Quality Air Quality
Division, to Martha Guzman, Regional Administrator, EPA Region IX
(submitted electronically August 15, 2022). On August 16, 2022, the
EPA determined that the SIP submittal met the completeness criteria
outlined in 40 CFR part 51, Appendix V. Letter dated August 16,
2022, from Elizabeth Adams, Director, Air and Radiation Division,
EPA Region IX, to Daniel Czecholinski, Director, Arizona Department
of Environmental Quality Air Quality Division.
\2\ Letter dated August 21, 2023, from Daniel Czecholinski,
Director, Arizona Department of Environmental Quality Air Quality
Division, to Martha Guzman, Regional Administrator, EPA Region IX
(submitted electronically August 25, 2023).
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II. Background and Requirements for Regional Haze Plans
A. Regional Haze Background
In the 1977 CAA Amendments, Congress created a program for
protecting visibility in the nation's mandatory Class I Federal areas,
which include certain national parks and wilderness areas.\3\ The CAA
establishes as a national goal the ``prevention of any future, and the
remedying of any existing, impairment of visibility in mandatory class
I Federal areas which impairment results from manmade air pollution.''
\4\ The CAA further directs the EPA to promulgate regulations to assure
reasonable progress toward meeting this national goal.\5\ On December
2, 1980, the EPA promulgated regulations to address visibility
impairment in mandatory Class I Federal areas (hereinafter referred to
as ``Class I areas'') that is ``reasonably attributable'' to a single
source or small group of sources.\6\ These regulations, codified at 40
CFR 51.300 through 51.307, represented the first phase of the EPA's
efforts to address visibility impairment. In 1990, Congress added
section 169B to the CAA to further address visibility impairment,
specifically, impairment from regional haze.\7\ The EPA promulgated the
Regional Haze Rule (RHR), codified at 40 CFR 51.308,\8\ on July 1,
1999.\9\ These regional haze regulations are a central component of the
EPA's comprehensive visibility protection program for Class I areas.
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\3\ CAA 169A. Areas statutorily designated as mandatory Class I
Federal areas consist of national parks exceeding 6,000 acres,
wilderness areas and national memorial parks exceeding 5,000 acres,
and all international parks that were in existence on August 7,
1977. CAA 162(a). There are 156 mandatory Class I areas. The list of
areas to which the requirements of the visibility protection program
apply is in 40 CFR part 81, subpart D.
\4\ CAA 169A(a)(1).
\5\ CAA 169A(a)(4).
\6\ 45 FR 80084 (December 2, 1980).
\7\ CAA 169B.
\8\ In addition to the generally applicable regional haze
provisions at 40 CFR 51.308, the EPA also promulgated regulations
specific to addressing regional haze visibility impairment in Class
I areas on the Colorado Plateau at 40 CFR 51.309. ADEQ submitted SIP
revisions to address the regional haze regulations at 40 CFR 51.309,
on December 23, 2003, December 30, 2004, and December 24, 2008. The
EPA approved certain burning and smoke management rules that were
part of the 2008 SIP submittal, but disapproved the remainder of
those submittals. 78 FR 48326 (August 8, 2013).
\9\ 64 FR 35714.
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Regional haze is visibility impairment that is produced by a
multitude of anthropogenic sources and activities which are located
across a broad geographic area and that emit pollutants that impair
visibility. Visibility impairing pollutants include fine and coarse
particulate matter (PM) (e.g., sulfates, nitrates, organic carbon,
elemental carbon, and soil dust) and their precursors (e.g., sulfur
dioxide (SO<INF>2</INF>), nitrogen oxides (NO<INF>X</INF>), and, in
some cases, volatile organic compounds (VOC) and ammonia
(NH<INF>3</INF>)). Fine particle precursors react in the atmosphere to
form PM<INF>2.5</INF>, which impairs visibility by scattering and
absorbing light. Visibility impairment reduces the perception of
clarity and color, as well as visible distance.\10\
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\10\ There are several ways to measure the amount of visibility
impairment, i.e., haze. One such measurement is the deciview, which
is the principal metric used by the RHR. Under many circumstances, a
change in one deciview will be perceived by the human eye to be the
same on both clear and hazy days. The deciview is unitless. It is
proportional to the logarithm of the atmospheric extinction of
light, which is the perceived dimming of light due to its being
scattered and absorbed as it passes through the atmosphere.
Atmospheric light extinction (b\ext\) is a metric used for
expressing visibility and is measured in inverse megameters
(Mm<SUP>-</SUP>\1\). The EPA's Guidance on Regional Haze State
Implementation Plans for the Second Implementation Period (``2019
Guidance'') offers the flexibility for the use of light extinction
in certain cases. Light extinction can be simpler to use in
calculations than deciviews, since it is not a logarithmic function.
See, e.g., 2019 Guidance, pp 16, 19, <a href="https://www.epa.gov/visibility/guidance-regional-haze-state-implementation-plans-second-implementation-period">https://www.epa.gov/visibility/guidance-regional-haze-state-implementation-plans-second-implementation-period</a>, The EPA Office of Air Quality Planning and
Standards, Research Triangle Park (August 20, 2019). The formula for
the deciview is 10 ln (b\ext\)/10 Mm - 1). 40 CFR 51.301.
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To address regional haze visibility impairment, the 1999 RHR
established an iterative planning process that requires both states in
which Class I areas are located and states ``the emissions from which
may reasonably be anticipated to cause or contribute to any impairment
of visibility'' in a Class I area to periodically submit SIP revisions
to address such impairment.\11\ Under the CAA, each SIP submission must
contain ``a long-term (ten to fifteen years) strategy for making
reasonable progress toward meeting the national goal.'' \12\ The
initial round of SIP submissions also had to address the statutory
requirement that certain older, larger sources of visibility impairing
pollutants install and operate the best available retrofit technology
(BART).\13\ States' first regional haze SIPs were due by December 17,
2007,\14\ with subsequent SIP submissions containing updated long-term
strategies originally due July 31, 2018, and every ten years
thereafter.\15\ The EPA established in the 1999 RHR that all states
either have Class I areas within their borders or ``contain sources
whose emissions are reasonably anticipated to contribute to regional
haze in a Class I area;'' therefore, all states must submit regional
haze SIPs.\16\
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\11\ CAA 169A(b)(2). The RHR expresses the statutory requirement
for states to submit plans addressing out-of-state class I areas by
providing that states must address visibility impairment ``in each
mandatory Class I Federal area located outside the State that may be
affected by emissions from within the State.'' 40 CFR 51.308(d),
(f). See also 40 CFR 51.308(b), (f) (establishing submission dates
for iterative regional haze SIP revisions); (64 FR at 35768, July 1,
1999).
\12\ CAA 169A(b)(2)(B).
\13\ CAA 169A(b)(2)(A); 40 CFR 51.308(d), (e).
\14\ 40 CFR 51.308(b).
\15\ 64 FR at 35768 (July 1, 1999).
\16\ Id. at 35721. In addition to each of the fifty states, the
EPA also concluded that the Virgin Islands and District of Columbia
must also submit regional haze SIPs because they either contain a
Class I area or contain sources whose emissions are reasonably
anticipated to contribute regional haze in a Class I area. See 40
CFR 51.300(b), (d)(3).
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Much of the focus in the first implementation period of the
regional haze program, which ran from 2007 through 2018, was on
satisfying states' BART obligations. First implementation period SIPs
were additionally required to contain long-term strategies for making
reasonable progress toward the national visibility goal, of which BART
is one component. The core required elements for the first
implementation period SIPs (other than BART) are laid out in 40 CFR
51.308(d). Those provisions required that states containing Class I
areas establish reasonable progress goals (RPGs) that are measured in
deciviews and reflect the anticipated visibility conditions at the end
of the implementation period including from implementation of states'
long-term strategies. The first planning period RPGs were required to
provide for an improvement in visibility for the most impaired days
over the period of the implementation plan and ensure no degradation in
visibility for the least impaired days over the same period. In
establishing the RPGs for any Class I area in a state, the state was
required to consider four statutory factors: the costs of compliance,
the time necessary for compliance, the energy and non-air quality
environmental impacts of compliance, and the remaining useful life of
any potentially affected sources.\17\
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\17\ CAA 169A(g)(1); 40 CFR 51.308(d)(1).
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States were also required to calculate baseline (using the five
year period of 2000-2004) and natural visibility conditions (i.e.,
visibility conditions without anthropogenic visibility impairment) for
each Class I area, and to calculate the linear rate of progress needed
to attain natural visibility conditions, assuming a starting point of
baseline visibility conditions in 2004
[[Page 47400]]
and ending with natural conditions in 2064. This linear interpolation
is known as the uniform rate of progress (URP) and is used as a
tracking metric to help states assess the amount of progress they are
making towards the national visibility goal over time in each Class I
area.\18\ The 1999 RHR also provided that States' long-term strategies
must include the ``enforceable emissions limitations, compliance,
schedules, and other measures as necessary to achieve the reasonable
progress goals.'' \19\ In establishing their long-term strategies,
states are required to consult with other states that also contribute
to visibility impairment in a given Class I area and include all
measures necessary to obtain their shares of the emission reductions
needed to meet the RPGs.\20\ Section 51.308(d) also contains seven
additional factors states must consider in formulating their long-term
strategies,\21\ as well as provisions governing monitoring and other
implementation plan requirements.\22\ Finally, the 1999 RHR required
states to submit periodic progress reports, which are SIP revisions due
every five years that contain information on states' implementation of
their regional haze plans and an assessment of whether anything
additional is needed to make reasonable progress,\23\ and to consult
with the Federal Land Manager(s) \24\ (FLMs) responsible for each Class
I area according to the requirements in CAA section 169A(d) and 40 CFR
51.308(i).
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\18\ 40 CFR 51.308(d)(1)(i)(B), (d)(2). The EPA established the
URP framework in the 1999 RHR to provide ``an equitable analytical
approach'' to assessing the rate of visibility improvement at Class
I areas across the country. The starting point for the URP analysis
is 2004 and the endpoint was calculated based on the amount of
visibility improvement that was anticipated to result from
implementation of existing CAA programs over the period from the
mid-1990s to approximately 2005. Assuming this rate of progress
would continue into the future, the EPA determined that natural
visibility conditions would be reached in 60 years, or 2064 (60
years from the baseline starting point of 2004). However, the EPA
did not establish 2064 as the year by which the national goal must
be reached. 64 FR at 35731-32. That is, the URP and the 2064 date
are not enforceable targets but are rather tools that ``allow for
analytical comparisons between the rate of progress that would be
achieved by the state's chosen set of control measures and the
URP.'' 82 FR 3078, 3084 (January 10, 2017).
\19\ 40 CFR 51.308(d)(3).
\20\ 40 CFR 51.308(d)(3)(i), (ii).
\21\ 40 CFR 51.308(d)(3)(v).
\22\ 40 CFR 51.308(d)(4).
\23\ See 40 CFR 51.308(g), (h).
\24\ The EPA's regulations define ``Federal Land Manager'' as
``the Secretary of the department with authority over the Federal
Class I area (or the Secretary's designee) or, with respect to
Roosevelt-Campobello International Park, the Chairman of the
Roosevelt-Campobello International Park Commission.'' 40 CFR 51.301.
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On January 10, 2017, the EPA promulgated revisions to the RHR,
which apply for the second and subsequent implementation periods.\25\
The 2017 rulemaking made several changes to the requirements for
regional haze SIPs to clarify States' obligations and streamline
certain regional haze requirements. The revisions to the regional haze
program for the second and subsequent implementation periods focused on
the requirement that States' SIPs contain long-term strategies for
making reasonable progress towards the national visibility goal. The
reasonable progress requirements as revised in the 2017 rulemaking
(referred to here as the 2017 RHR Revisions) are codified at 40 CFR
51.308(f). Among other changes, the 2017 RHR Revisions adjusted the
deadline for States to submit their second implementation period SIPs
from July 31, 2018, to July 31, 2021, clarified the order of analysis
and the relationship between RPGs and the long-term strategy, and
focused on making visibility improvements on the days with the most
anthropogenic visibility impairment, as opposed to the days with the
most visibility impairment overall. The EPA also revised requirements
of the visibility protection program related to periodic progress
reports and FLM consultation. The specific requirements applicable to
second implementation period regional haze SIP submissions are
addressed in detail in Section III of this document.
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\25\ 82 FR 3078.
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The EPA provided guidance to the states for their second
implementation period SIP submissions in the preamble to the 2017 RHR
Revisions as well as in subsequent, stand-alone guidance documents. In
August 2019, the EPA issued ``Guidance on Regional Haze State
Implementation Plans for the Second Implementation Period'' (``2019
Guidance'').\26\ On July 8, 2021, the EPA issued a memorandum
containing ``Clarifications Regarding Regional Haze State
Implementation Plans for the Second Implementation Period'' (``2021
Clarifications Memo'').\27\ Additionally, the EPA further clarified the
recommended procedures for processing ambient visibility data and
optionally adjusting the URP to account for international anthropogenic
and prescribed fire impacts in two technical guidance documents: the
December 2018 ``Technical Guidance on Tracking Visibility Progress for
the Second Implementation Period of the Regional Haze Program'' (``2018
Visibility Tracking Guidance''),\28\ and the June 2020 ``Recommendation
for the Use of Patched and Substituted Data and Clarification of Data
Completeness for Tracking Visibility Progress for the Second
Implementation Period of the Regional Haze Program'' and associated
Technical Addendum (``2020 Data Completeness Memo'').\29\
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\26\ Guidance on Regional Haze State Implementation Plans for
the Second Implementation Period. <a href="https://www.epa.gov/visibility/guidance-regional-haze-state-implementation-plans-second-implementation-period">https://www.epa.gov/visibility/guidance-regional-haze-state-implementation-plans-second-implementation-period</a>. The EPA Office of Air Quality Planning and
Standards, Research Triangle Park (August 20, 2019).
\27\ Clarifications Regarding Regional Haze State Implementation
Plans for the Second Implementation Period. <a href="https://www.epa.gov/system/files/documents/2021-07/clarifications-regarding-regional-haze-state-implementation-plans-for-the-second-implementation-period.pdf">https://www.epa.gov/system/files/documents/2021-07/clarifications-regarding-regional-haze-state-implementation-plans-for-the-second-implementation-period.pdf</a>. The EPA Office of Air Quality Planning and Standards,
Research Triangle Park (July 8, 2021).
\28\ Technical Guidance on Tracking Visibility Progress for the
Second Implementation Period of the Regional Haze Program. <a href="https://www.epa.gov/visibility/technical-guidance-tracking-visibility-progress-second-implementation-period-regional">https://www.epa.gov/visibility/technical-guidance-tracking-visibility-progress-second-implementation-period-regional</a> The EPA Office of Air
Quality Planning and Standards, Research Triangle Park. (December
20, 2018).
\29\ Recommendation for the Use of Patched and Substituted Data
and Clarification of Data Completeness for Tracking Visibility
Progress for the Second Implementation Period of the Regional Haze
Program. <a href="https://www.epa.gov/visibility/memo-and-technical-addendum-ambient-data-usage-and-completeness-regional-haze-program">https://www.epa.gov/visibility/memo-and-technical-addendum-ambient-data-usage-and-completeness-regional-haze-program</a> The EPA
Office of Air Quality Planning and Standards, Research Triangle Park
(June 3, 2020).
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As explained in the 2021 Clarifications Memo, the EPA intends the
second implementation period of the regional haze program to secure
meaningful reductions in visibility impairing pollutants that build on
the significant progress states have achieved to date. The Agency also
recognizes that analyses regarding reasonable progress are state-
specific and that, based on states' and sources' individual
circumstances, what constitutes reasonable reductions in visibility
impairing pollutants will vary from state-to-state. While there exist
many opportunities for states to leverage both ongoing and upcoming
emissions reductions under other CAA programs, the Agency expects
states to undertake rigorous reasonable progress analyses that identify
further opportunities to advance the national visibility goal
consistent with the statutory and regulatory requirements.\30\ This is
consistent with Congress's determination that a visibility protection
program is needed in addition to the CAA's NAAQS and Prevention of
Significant Deterioration (PSD) programs, as further emissions
reductions may be necessary to adequately protect visibility in Class I
areas throughout the country.\31\
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\30\ See generally 2021 Clarifications Memo.
\31\ See, e.g., H.R. Rep No. 95-294 p. 205 (``In determining how
to best remedy the growing visibility problem in these areas of
great scenic importance, the committee realizes that as a matter of
equity, the national ambient air quality standards cannot be revised
to adequately protect visibility in all areas of the country.''),
(``the mandatory class I increments of [the PSD program] do not
adequately protect visibility in class I areas'').
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[[Page 47401]]
B. Roles of Agencies in Addressing Regional Haze
Because the air pollutants and pollution affecting visibility in
Class I areas can be transported over long distances, successful
implementation of the regional haze program requires long-term,
regional coordination among multiple jurisdictions and agencies that
have responsibility for Class I areas and the emissions that impact
visibility in those areas. To address regional haze, states need to
develop strategies in coordination with one another, considering the
effect of emissions from one jurisdiction on the air quality in
another. Five regional planning organizations (RPOs),\32\ which include
representation from state and Tribal governments, the EPA, and FLMs,
were developed in the lead-up to the first implementation period to
address regional haze. RPOs evaluate technical information to better
understand how emissions from State and Tribal land impact Class I
areas across the country, pursue the development of regional strategies
to reduce emissions of particulate matter and other pollutants leading
to regional haze, and help states meet the consultation requirements of
the RHR.
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\32\ RPOs are sometimes also referred to as ``multi-
jurisdictional organizations,'' or MJOs. For the purposes of this
notice, the terms RPO and MJO are synonymous.
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The Western Regional Air Partnership (WRAP), one of the five RPOs,
is a collaborative effort of state governments, Tribal governments, and
various Federal agencies established to initiate and coordinate
activities associated with the management of regional haze, visibility,
and other air quality issues in the western corridor of the United
States. Member states (listed alphabetically) include: Alaska, Arizona,
California, Colorado, Idaho, Montana, Nevada, New Mexico, North Dakota,
Oregon, South Dakota, Utah, Washington, and Wyoming. The Federal
partner members of WRAP are the EPA, U.S. National Parks Service (NPS),
U.S. Fish and Wildlife Service (FWS), and U.S. Forest Service (USFS).
There are also 468 federally recognized Tribes within the WRAP region.
III. Requirements for Regional Haze Plans for the Second Implementation
Period
Under the CAA and the EPA's regulations, all 50 states, the
District of Columbia, and the U.S. Virgin Islands were required to
submit regional haze SIP revisions satisfying the applicable
requirements for the second implementation period of the regional haze
program by July 31, 2021. Each state's SIP must contain a long-term
strategy for making reasonable progress toward meeting the national
goal of remedying any existing and preventing any future anthropogenic
visibility impairment in Class I areas.\33\ To this end, section
51.308(f) lays out the process by which states determine what
constitutes their long-term strategies, with the order of the
requirements in section 51.308(f)(1) through (3) generally mirroring
the order of the steps in the reasonable progress analysis \34\ and
(f)(4) through (6) containing additional, related requirements. Broadly
speaking, a state first must identify the Class I areas within the
state and determine the Class I areas outside the state in which
visibility may be affected by emissions from the state. These are the
Class I areas that must be addressed in the state's long-term
strategy.\35\ For each Class I area within its borders, a state must
then calculate the baseline, current, and natural visibility conditions
for that area, as well as the visibility improvement made to date and
the URP.\36\ Each state having a Class I area and/or emissions that may
affect visibility in a Class I area must then develop a long-term
strategy that includes the enforceable emissions limitations,
compliance schedules, and other measures that are necessary to make
reasonable progress in such areas. A reasonable progress determination
is based on applying the four factors in CAA section 169A(g)(1) to
sources of visibility-impairing pollutants that the state has selected
to assess for controls for the second implementation period.
Additionally, as further explained below, the RHR at 40 CFR
51.308(f)(2)(iv) separately provides five ``additional factors'' \37\
that states must consider in developing their long-term strategies.\38\
A state evaluates potential emissions reduction measures for those
selected sources and determines which are necessary to make reasonable
progress. Those measures are then incorporated into the state's long-
term strategy. After a state has developed its long-term strategy, it
then establishes RPGs for each Class I area within its borders by
modeling the visibility impacts of all reasonable progress controls at
the end of the second implementation period, i.e., in 2028, as well as
the impacts of other requirements of the CAA. The RPGs include
reasonable progress controls not only for sources in the state in which
the Class I area is located, but also for sources in other states that
contribute to visibility impairment in that area. The RPGs are then
compared to the baseline visibility conditions and the URP to ensure
that progress is being made towards the statutory goal of preventing
any future and remedying any existing anthropogenic visibility
impairment in Class I areas.\39\
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\33\ CAA 169A(b)(2)(B).
\34\ The EPA explained in the 2017 RHR Revisions that we were
adopting new regulatory language in 40 CFR 51.308(f) that, unlike
the structure in 51.308(d), ``tracked the actual planning
sequence.'' 82 FR 3091 (January 10, 2017).
\35\ See 40 CFR 51.308(f), (f)(2).
\36\ See 40 CFR 51.308(f)(1).
\37\ The five ``additional factors'' for consideration in
section 51.308(f)(2)(iv) are distinct from the four factors listed
in CAA section 169A(g)(1) and 40 CFR 51.308(f)(2)(i) that states
must consider and apply to sources in determining reasonable
progress.
\38\ See 40 CFR 51.308(f)(2).
\39\ 40 CFR 51.308(f)(2)-(3).
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In addition to satisfying the requirements at 40 CFR 51.308(f)
related to reasonable progress, the regional haze SIP revisions for the
second implementation period must address the requirements in section
51.308(g)(1) through (5) pertaining to periodic reports describing
progress towards the RPGs,\40\ as well as requirements for FLM
consultation that apply to all visibility protection SIPs and SIP
revisions.\41\
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\40\ 40 CFR 51.308(f)(5).
\41\ 40 CFR 51.308(i).
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A state must submit its regional haze SIP and subsequent SIP
revisions to the EPA according to the requirements applicable to all
SIP revisions under the CAA and the EPA's regulations.\42\ Upon EPA
approval, a SIP is enforceable by the Agency and the public under the
CAA. If the EPA finds that a state failed to make a required SIP
revision, or if the EPA finds that a state's SIP is incomplete or
disapproves the SIP, the Agency must promulgate a federal
implementation plan (FIP) that satisfies the applicable
requirements.\43\
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\42\ See CAA 169A(b)(2); CAA 110(a).
\43\ CAA 110(c)(1).
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A. Identification of Class I Areas
The first step in developing a regional haze SIP is for a state to
determine which Class I areas, in addition to those within its borders,
``may be affected'' by emissions from within the state. In the 1999
RHR, the EPA determined that all states contribute to visibility
impairment in at least one Class I area,\44\ and explained that the
statute and regulations lay out an ``extremely low triggering
threshold'' for determining
[[Page 47402]]
``whether States should be required to engage in air quality planning
and analysis as a prerequisite to determining the need for control of
emissions from sources within their State.'' \45\
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\44\ 64 FR 35720-22.
\45\ Id. at 35721.
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A state must determine which Class I areas must be addressed by its
SIP by evaluating the total emissions of visibility impairing
pollutants from all sources within the state. While the RHR does not
require this evaluation to be conducted in any particular manner, the
EPA's 2019 Guidance provides recommendations for how such an assessment
might be accomplished, including by, where appropriate, using the
determinations previously made for the first implementation period.\46\
In addition, the determination of which Class I areas may be affected
by a state's emissions is subject to the requirement in 40 CFR
51.308(f)(2)(iii) to ``document the technical basis, including
modeling, monitoring, cost, engineering, and emissions information, on
which the State is relying to determine the emission reduction measures
that are necessary to make reasonable progress in each mandatory Class
I Federal area it affects.''
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\46\ 2019 Guidance, pp. 8-9.
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B. Calculations of Baseline, Current, and Natural Visibility
Conditions; Progress to Date; and the Uniform Rate of Progress
As part of assessing whether a SIP submission for the second
implementation period is providing for reasonable progress towards the
national visibility goal, the RHR contains requirements in section
51.308(f)(1) related to tracking visibility improvement over time. The
requirements of this section apply only to states that have Class I
areas within their borders; the required calculations must be made for
each such Class I area. The EPA's 2018 Visibility Tracking Guidance
\47\ provides recommendations to assist states in satisfying their
obligations under section 51.308(f)(1); specifically, in developing
information on baseline, current, and natural visibility conditions,
and in making optional adjustments to the URP to account for the
impacts of international anthropogenic emissions and prescribed fires.
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\47\ The 2018 Visibility Tracking Guidance references and relies
on parts of the 2003 Tracking Guidance: ``Guidance for Tracking
Progress Under the Regional Haze Rule,'' which can be found at
<a href="https://www.epa.gov/sites/default/files/2021-03/documents/tracking.pdf">https://www.epa.gov/sites/default/files/2021-03/documents/tracking.pdf</a>.
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The RHR requires tracking of visibility conditions on two sets of
days: the clearest and the most impaired days. Visibility conditions
for both sets of days are expressed as the average deciview index for
the relevant five-year period (the period representing baseline or
current visibility conditions). The RHR provides that the relevant sets
of days for visibility tracking purposes are the 20 percent clearest
(the 20 percent of monitored days in a calendar year with the lowest
values of the deciview index) and 20 percent most impaired days (the 20
percent of monitored days in a calendar year with the highest amounts
of anthropogenic visibility impairment).\48\ A state must calculate
visibility conditions for both the 20 percent clearest and 20 percent
most impaired days for the baseline period of 2000-2004 and the most
recent five-year period for which visibility monitoring data are
available (representing current visibility conditions).\49\ States must
also calculate natural visibility conditions for the clearest and most
impaired days,\50\ by estimating the conditions that would exist on
those two sets of days absent anthropogenic visibility impairment.\51\
Using all these data, states must then calculate, for each Class I
area, the amount of progress made since the baseline period (2000-2004)
and how much improvement is left to achieve to reach natural visibility
conditions.
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\48\ 40 CFR 51.301. This notice also refers to the 20 percent
clearest and 20 percent most anthropogenically impaired days as the
``clearest'' and ``most impaired'' or ``most anthropogenically
impaired'' days, respectively.
\49\ 40 CFR 51.308(f)(1)(i), (iii).
\50\ The RHR at 40 CFR 51.308(f)(1)(ii) contains an error
related to the requirement for calculating two sets of natural
conditions values. The rule says ``most impaired days or the
clearest days'' where it should say ``most impaired days and
clearest days.'' This is an error that was intended to be corrected
in the 2017 RHR Revisions but did not get corrected in the final
rule language. This is supported by the preamble text at 82 FR 3098:
``In the final version of 40 CFR 51.308(f)(1)(ii), an occurrence of
``or'' has been corrected to ``and'' to indicate that natural
visibility conditions for both the most impaired days and the
clearest days must be based on available monitoring information.''
\51\ 40 CFR 51.308(f)(1)(ii).
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Using the data for the set of most impaired days only, states must
plot a line between visibility conditions in the baseline period and
natural visibility conditions for each Class I area to determine the
URP--the amount of visibility improvement, measured in deciviews, that
would need to be achieved during each implementation period to achieve
natural visibility conditions by the end of 2064. The URP is used in
later steps of the reasonable progress analysis for informational
purposes and to provide a non-enforceable benchmark against which to
assess a Class I area's rate of visibility improvement.\52\
Additionally, in the 2017 RHR Revisions, the EPA provided states the
option of proposing to adjust the endpoint of the URP to account for
impacts of anthropogenic sources outside the United States and/or
impacts of certain types of wildland prescribed fires. These
adjustments, which must be approved by the EPA, are intended to avoid
any perception that states should compensate for impacts from
international anthropogenic sources and to give states the flexibility
to determine that limiting the use of wildland-prescribed fire is not
necessary for reasonable progress.\53\
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\52\ Being on or below the URP is not a ``safe harbor''; i.e.,
achieving the URP does not mean that a Class I area is making
``reasonable progress'' and does not relieve a state from using the
four statutory factors to determine what level of control is needed
to achieve such progress. See, e.g., 82 FR 3093.
\53\ 82 FR 3107 footnote 116.
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The EPA's 2018 Visibility Tracking Guidance can be used to help
satisfy the 40 CFR 51.308(f)(1) requirements, including in developing
information on baseline, current, and natural visibility conditions,
and in making optional adjustments to the URP. In addition, the 2020
Data Completeness Memo provides recommendations on the data
completeness language referenced in section 51.308(f)(1)(i) and
provides updated natural conditions estimates for each Class I area.
C. Long-Term Strategy for Regional Haze
The core component of a regional haze SIP submission is a long-term
strategy that addresses regional haze in each Class I area within a
state's borders and each Class I area that may be affected by emissions
from the state. The long-term strategy ``must include the enforceable
emissions limitations, compliance schedules, and other measures that
are necessary to make reasonable progress, as determined pursuant to
(f)(2)(i) through (iv).'' \54\ The amount of progress that is
``reasonable progress'' is based on applying the four statutory factors
in CAA section 169A(g)(1) in an evaluation of potential control options
for sources of visibility impairing pollutants, which is referred to as
a ``four-factor'' analysis. The outcome of that analysis is the
emissions reduction measures that a particular source or group of
sources needs to implement to make reasonable progress towards the
national visibility goal.\55\ Emissions reduction measures that are
necessary to make reasonable progress may be either new, additional
control measures for a source, or they
[[Page 47403]]
may be the existing emissions reduction measures that a source is
already implementing.\56\ Such measures must be represented by
``enforceable emissions limitations, compliance schedules, and other
measures'' (i.e., any additional compliance tools) in a state's long-
term strategy in its SIP.\57\
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\54\ 40 CFR 51.308(f)(2).
\55\ See 40 CFR 51.308(f)(2)(i).
\56\ See 2019 Guidance, p. 43; 2021 Clarifications Memo, pp. 8-
10.
\57\ 40 CFR 51.308(f)(2).
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Section 51.308(f)(2)(i) provides the requirements for the four-
factor analysis. The first step of this analysis entails selecting the
sources to be evaluated for emissions reduction measures; to this end,
states should consider ``major and minor stationary sources or groups
of sources, mobile sources, and area sources'' of visibility impairing
pollutants for potential four-factor control analysis.\58\ A threshold
question at this step is which visibility impairing pollutants will be
analyzed. As the EPA previously explained, consistent with the first
implementation period, the EPA generally expects that each state will
analyze at least SO<INF>2</INF> and NO<INF>X</INF> in selecting sources
and determining control measures.\59\ A state that chooses not to
consider at least these two pollutants should demonstrate why such
consideration would be unreasonable.\60\
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\58\ 40 CFR 51.308(f)(2)(i).
\59\ See 2019 Guidance, p. 12; 2021 Clarifications Memo, p. 4.
\60\ 2021 Clarifications Memo, p. 4.
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While states have the option to analyze all sources, the 2019
Guidance explains that ``an analysis of control measures is not
required for every source in each implementation period,'' and that
``[s]electing a set of sources for analysis of control measures in each
implementation period is . . . consistent with the Regional Haze Rule,
which sets up an iterative planning process and anticipates that a
state may not need to analyze control measures for all its sources in a
given SIP revision.'' \61\ However, given that source selection is the
basis of all subsequent control determinations, a reasonable source
selection process ``should be designed and conducted to ensure that
source selection results in a set of pollutants and sources the
evaluation of which has the potential to meaningfully reduce their
contributions to visibility impairment.'' \62\
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\61\ 2019 Guidance, p. 9.
\62\ 2021 Clarifications Memo, p. 3.
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The EPA explained in the 2021 Clarifications Memo that each state
has an obligation to submit a long-term strategy that addresses the
regional haze visibility impairment that results from emissions from
within that state. Thus, source selection should focus on the in-state
contribution to visibility impairment and be designed to capture a
meaningful portion of the state's total contribution to visibility
impairment in Class I areas. A state should not decline to select its
largest in-state sources on the basis that there are even larger out-
of-state contributors.\63\
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\63\ Id. at 4. Similarly, in responding to comments on the 2017
RHR Revisions, the EPA explained that ``[a] state should not fail to
address its many relatively low-impact sources merely because it
only has such sources and another state has even more low-impact
sources and/or some high impact sources.'' Responses to Comments on
Protection of Visibility: Amendments to Requirements for State
Plans; Proposed Rule (81 FR 26942, May 4, 2016), pp. 87-88.
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Thus, while states have discretion to choose any source selection
methodology that is reasonable, whatever choices they make should be
reasonably explained. To this end, 40 CFR 51.308(f)(2)(i) requires that
a state's SIP submission include ``a description of the criteria it
used to determine which sources or groups of sources it evaluated.''
The technical basis for source selection, which may include methods for
quantifying potential visibility impacts such as emissions divided by
distance metrics, trajectory analyses, residence time analyses, and/or
photochemical modeling, must also be appropriately documented, as
required by 40 CFR 51.308(f)(2)(iii).
Once a state has selected the set of sources, the next step is to
determine the emissions reduction measures for those sources that are
necessary to make reasonable progress for the second implementation
period.\64\ This is accomplished by considering the four factors--``the
costs of compliance, the time necessary for compliance, and the energy
and non-air quality environmental impacts of compliance, and the
remaining useful life of any existing source subject to such
requirements.'' \65\ The EPA has explained that the four-factor
analysis is an assessment of potential emissions reduction measures
(i.e., control options) for sources; ``use of the terms `compliance'
and `subject to such requirements' in section 169A(g)(1) strongly
indicates that Congress intended the relevant determination to be the
requirements with which sources would have to comply to satisfy the
CAA's reasonable progress mandate.'' \66\ Thus, for each source it has
selected for four-factor analysis,\67\ a state must consider a
``meaningful set'' of technically feasible control options for reducing
emissions of visibility impairing pollutants.\68\ The 2019 Guidance
provides that ``[a] state must reasonably pick and justify the measures
that it will consider, recognizing that there is no statutory or
regulatory requirement to consider all technically feasible measures or
any particular measures. A range of technically feasible measures
available to reduce emissions would be one way to justify a reasonable
set.'' \69\
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\64\ The CAA provides that, ``[i]n determining reasonable
progress there shall be taken into consideration'' the four
statutory factors. CAA 169A(g)(1). However, in addition to four-
factor analyses for selected sources, groups of sources, or source
categories, a state may also consider additional emissions reduction
measures for inclusion in its long-term strategy, e.g., from other
newly adopted, on-the-books, or on-the-way rules and measures for
sources not selected for four-factor analysis for the second
planning period.
\65\ CAA 169A(g)(1).
\66\ 82 FR 3091.
\67\ ``Each source'' or ``particular source'' is used here as
shorthand. While a source-specific analysis is one way of applying
the four factors, neither the statute nor the RHR requires states to
evaluate individual sources. Rather, states have ``the flexibility
to conduct four-factor analyses for specific sources, groups of
sources or even entire source categories, depending on state policy
preferences and the specific circumstances of each state.'' 82 FR at
3088. However, not all approaches to grouping sources for four-
factor analysis are necessarily reasonable; the reasonableness of
grouping sources in any particular instance will depend on the
circumstances and the manner in which grouping is conducted. If it
is feasible to establish and enforce different requirements for
sources or subgroups of sources, and if relevant factors can be
quantified for those sources or subgroups, then states should make a
separate reasonable progress determination for each source or
subgroup. 2021 Clarifications Memo, pp. 7-8.
\68\ Id. at 3088.
\69\ 2019 Guidance, p. 29.
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The EPA's 2021 Clarifications Memo provides further guidance on
what constitutes a reasonable set of control options for consideration:
``A reasonable four-factor analysis will consider the full range of
potentially reasonable options for reducing emissions.'' \70\ In
addition to add-on controls and other retrofits (i.e., new emissions
reduction measures for sources), the EPA explained that states should
generally analyze efficiency improvements for sources' existing
measures as control options in their four-factor analyses, as in many
cases such improvements are reasonable given that they typically
involve only additional operation and maintenance costs. Additionally,
the 2021 Clarifications Memo provides that states that have assumed a
higher emissions rate than a source has achieved or could potentially
achieve using its existing measures should also consider lower
emissions rates as potential control options. That is, a state should
consider a source's recent actual and projected emissions rates to
determine if it could reasonably attain lower emissions rates with its
existing
[[Page 47404]]
measures. If so, the state should analyze the lower emissions rate as a
control option for reducing emissions.\71\ The EPA's recommendations to
analyze potential efficiency improvements and achievable lower
emissions rates apply to both sources that have been selected for four-
factor analysis and those that have forgone a four-factor analysis on
the basis of existing ``effective controls.'' \72\
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\70\ 2021 Clarifications Memo, p. 7.
\71\ Id. at 7.
\72\ Id. at 5, 10.
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After identifying a reasonable set of potential control options for
the sources it has selected, a state then collects information on the
four factors with regard to each option identified. The EPA has also
explained that, in addition to the four statutory factors, states have
flexibility under the CAA and RHR to reasonably consider visibility
benefits as an additional factor alongside the four statutory
factors.\73\ The 2019 Guidance provides recommendations for the types
of information that can be used to characterize the four factors (with
or without visibility), as well as ways in which states might
reasonably consider and balance that information to determine which of
the potential control options is necessary to make reasonable
progress.\74\ The 2021 Clarifications Memo contains further guidance on
how states can reasonably consider modeled visibility impacts or
benefits in the context of a four-factor analysis.\75\ Specifically,
the EPA explained that while visibility can reasonably be used when
comparing and choosing between multiple reasonable control options, it
should not be used to summarily reject controls that are reasonable
given the four statutory factors.\76\ Ultimately, while states have
discretion to reasonably weigh the factors and to determine what level
of control is needed, section 51.308(f)(2)(i) provides that a state
``must include in its implementation plan a description of . . . how
the four factors were taken into consideration in selecting the measure
for inclusion in its long-term strategy.''
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\73\ See, e.g., Responses to Comments on Protection of
Visibility: Amendments to Requirements for State Plans; Proposed
Rule (81 FR 26942, May 4, 2016), Docket Number EPA-HQ-OAR-2015-0531,
U.S. Environmental Protection Agency at 186; 2019 Guidance, pp. 36-
37.
\74\ See 2019 Guidance, pp. 30-36.
\75\ 2021 Clarifications Memo, pp. 12-15.
\76\ Id. at 13.
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As explained above, section 51.308(f)(2)(i) requires states to
determine the emissions reduction measures for sources that are
necessary to make reasonable progress by considering the four factors.
Pursuant to section 51.308(f)(2), measures that are necessary to make
reasonable progress towards the national visibility goal must be
included in a state's long-term strategy and in its SIP.\77\ If the
outcome of a four-factor analysis is a new, additional emissions
reduction measure for a source, that new measure is necessary to make
reasonable progress towards remedying existing anthropogenic visibility
impairment and must be included in the SIP. If the outcome of a four-
factor analysis is that no new measures are reasonable for a source,
continued implementation of the source's existing measures is generally
necessary to prevent future emissions increases and thus to make
reasonable progress towards the second part of the national visibility
goal: preventing future anthropogenic visibility impairment.\78\ That
is, when the result of a four-factor analysis is that no new measures
are necessary to make reasonable progress, the source's existing
measures are generally necessary to make reasonable progress and must
be included in the SIP. However, there may be circumstances in which a
state can demonstrate that a source's existing measures are not
necessary to make reasonable progress. Specifically, if a state can
demonstrate that a source will continue to implement its existing
measures and will not increase its emissions rate, it may not be
necessary to have those measures in the long-term strategy to prevent
future emissions increases and future visibility impairment. The EPA's
2021 Clarifications Memo provides further explanation and guidance on
how states may demonstrate that a source's existing measures are not
necessary to make reasonable progress.\79\ If the state can make such a
demonstration, it need not include a source's existing measures in the
long-term strategy or its SIP.
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\77\ States may choose to, but are not required to, include
measures in their long-term strategies beyond just the emission
reduction measures that are necessary for reasonable progress. See
2021 Clarifications Memo, p. 16. For example, states with smoke
management programs may choose to submit their smoke management
plans to the EPA for inclusion in their SIPs but are not required to
do so. See, e.g., 82 FR at 3108-09 (requirement to consider smoke
management practices and smoke management programs under 40 CFR
51.308(f)(2)(iv) does not require states to adopt such practices or
programs into their SIPs, although they may elect to do so).
\78\ See CAA 169A(a)(1).
\79\ See 2021 Clarifications Memo, pp. 8-10.
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As with source selection, the characterization of information on
each of the factors is also subject to the documentation requirement in
section 51.308(f)(2)(iii). The reasonable progress analysis, including
source selection, information gathering, characterization of the four
statutory factors (and potentially visibility), balancing of the four
factors, and selection of the emissions reduction measures that
represent reasonable progress, is a technically complex exercise, but
also a flexible one that provides states with bounded discretion to
design and implement approaches appropriate to their circumstances.
Given this flexibility, section 51.308(f)(2)(iii) plays an important
function in requiring a state to document the technical basis for its
decision making so that the public and the EPA can comprehend and
evaluate the information and analysis the state relied upon to
determine what emissions reduction measures must be in place to make
reasonable progress. The technical documentation must include the
modeling, monitoring, cost, engineering, and emissions information on
which the state relied to determine the measures necessary to make
reasonable progress. This documentation requirement can be met through
the provision of and reliance on technical analyses developed through a
regional planning process, so long as that process and its output has
been approved by all state participants. In addition to the explicit
regulatory requirement to document the technical basis of their
reasonable progress determinations, states are also subject to the
general principle that those determinations must be reasonably moored
to the statute.\80\ That is, a state's decisions about the emissions
reduction measures that are necessary to make reasonable progress must
be consistent with the statutory goal of remedying existing and
preventing future visibility impairment.
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\80\ See Arizona ex rel. Darwin v. U.S. EPA, 815 F.3d 519, 531
(9th Cir. 2016); Nebraska v. U.S. EPA, 812 F.3d 662, 668 (8th Cir.
2016); North Dakota v. EPA, 730 F.3d 750, 761 (8th Cir. 2013);
Oklahoma v. EPA, 723 F.3d 1201, 1206, 1208-10 (10th Cir. 2013); cf.
also Nat'l Parks Conservation Ass'n v. EPA, 803 F.3d 151, 165 (3d
Cir. 2015); Alaska Dep't of Envtl. Conservation v. EPA, 540 U.S.
461, 485, 490 (2004).
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The four statutory factors (and potentially visibility) are used to
determine what emissions reduction measures for selected sources must
be included in a state's long-term strategy for making reasonable
progress. Additionally, the RHR at 40 CFR 51.3108(f)(2)(iv) separately
provides five ``additional factors'' \81\ that states must consider in
developing their long-term strategies: (1) Emissions reductions due
[[Page 47405]]
to ongoing air pollution control programs, including measures to
address reasonably attributable visibility impairment; (2) measures to
reduce the impacts of construction activities; (3) source retirement
and replacement schedules; (4) basic smoke management practices for
prescribed fire used for agricultural and wildland vegetation
management purposes and smoke management programs; and (5) the
anticipated net effect on visibility due to projected changes in point,
area, and mobile source emissions over the period addressed by the
long-term strategy. The 2019 Guidance provides that a state may satisfy
this requirement by considering these additional factors in the process
of selecting sources for four-factor analysis, when performing that
analysis, or both, and that not every one of the additional factors
needs to be considered at the same stage of the process.\82\ The EPA
provided further guidance on the five additional factors in the 2021
Clarifications Memo, explaining that a state should generally not
reject cost-effective and otherwise reasonable controls merely because
there have been emissions reductions since the first planning period
owing to other ongoing air pollution control programs or merely because
visibility is otherwise projected to improve at Class I areas.
Additionally, states generally should not rely on these additional
factors to summarily assert that the state has already made sufficient
progress and, therefore, no sources need to be selected or no new
controls are needed regardless of the outcome of four-factor
analyses.\83\
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\81\ The five ``additional factors'' for consideration in
section 51.308(f)(2)(iv) are distinct from the four factors listed
in CAA section 169A(g)(1) and 40 CFR 51.308(f)(2)(i) that states
must consider and apply to sources in determining reasonable
progress.
\82\ See 2019 Guidance, p. 21.
\83\ 2021 Clarifications Memo, p. 13.
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Because the air pollution that causes regional haze crosses state
boundaries, section 51.308(f)(2)(ii) requires a state to consult with
other states that also have emissions that are reasonably anticipated
to contribute to visibility impairment in a given Class I area.
Consultation allows for each state that impacts visibility in an area
to share whatever technical information, analyses, and control
determinations may be necessary to develop coordinated emissions
management strategies. This coordination may be managed through inter-
and intra-RPO consultation and the development of regional emissions
strategies; additional consultations between states outside of RPO
processes may also occur. If a state, pursuant to consultation, agrees
that certain measures (e.g., a certain emissions limitation) are
necessary to make reasonable progress at a Class I area, it must
include those measures in its SIP.\84\ Additionally, the RHR requires
that states that contribute to visibility impairment at the same Class
I area consider the emissions reduction measures the other contributing
states have identified as being necessary to make reasonable progress
for their own sources.\85\ If a state has been asked to consider or
adopt certain emissions reduction measures, but ultimately determines
those measures are not necessary to make reasonable progress, that
state must document in its SIP the actions taken to resolve the
disagreement.\86\ The EPA will consider the technical information and
explanations presented by the submitting state and the state with which
it disagrees when considering whether to approve the state's SIP.\87\
Under all circumstances, a state must document in its SIP submission
all substantive consultations with other contributing states.\88\
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\84\ 40 CFR 51.308(f)(2)(ii)(A).
\85\ 40 CFR 51.308(f)(2)(ii)(B).
\86\ 40 CFR 51.308(f)(2)(ii)(C).
\87\ See id.; 2019 Guidance, p. 53.
\88\ 40 CFR 51.308(f)(2)(ii)(C).
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D. Reasonable Progress Goals
Reasonable progress goals ``measure the progress that is projected
to be achieved by the control measures states have determined are
necessary to make reasonable progress based on a four-factor
analysis.'' \89\ Their primary purpose is to assist the public and the
EPA in assessing the reasonableness of states' long-term strategies for
making reasonable progress towards the national visibility goal.\90\
States in which Class I areas are located must establish two RPGs, both
in deciviews--one representing visibility conditions on the clearest
days and one representing visibility on the most anthropogenically
impaired days--for each area within their borders.\91\ The two RPGs are
intended to reflect the projected impacts, on the two sets of days, of
the emissions reduction measures the state with the Class I area, as
well as all other contributing states, have included in their long-term
strategies for the second implementation period.\92\ The RPGs also
account for the projected impacts of implementing other CAA
requirements, including non-SIP based requirements. Because RPGs are
the modeled result of the measures in states' long-term strategies (as
well as other measures required under the CAA), they cannot be
determined before states have conducted their four-factor analyses and
determined the control measures that are necessary to make reasonable
progress.\93\
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\89\ 82 FR 3091.
\90\ See 40 CFR 51.308(f)(3)(iii)-(iv).
\91\ 40 CFR 51.308(f)(3)(i).
\92\ RPGs are intended to reflect the projected impacts of the
measures all contributing states include in their long-term
strategies. However, due to the timing of analyses and of control
determinations by other states, other on-going emissions changes, a
particular state's RPGs may not reflect all control measures and
emissions reductions that are expected to occur by the end of the
implementation period. The 2019 Guidance provides recommendations
for addressing the timing of RPG calculations when states are
developing their long-term strategies on disparate schedules, as
well as for adjusting RPGs using a post-modeling approach. 2019
Guidance, pp. 47-48.
\93\ See 2021 Clarifications Memo, p. 6.
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For the second implementation period, the RPGs are set for 2028.
Reasonable progress goals are not enforceable targets; \94\ rather,
they ``provide a way for the states to check the projected outcome of
the [long-term strategy] against the goals for visibility
improvement.'' \95\ While states are not legally obligated to achieve
the visibility conditions described in their RPGs, section
51.308(f)(3)(i) requires that ``[t]he long-term strategy and the
reasonable progress goals must provide for an improvement in visibility
for the most impaired days since the baseline period and ensure no
degradation in visibility for the clearest days since the baseline
period.'' Thus, states are required to have emissions reduction
measures in their long-term strategies that are projected to achieve
visibility conditions on the most impaired days that are better than
the baseline period and shows no degradation on the clearest days
compared to the clearest days from the baseline period. The baseline
period for the purpose of this comparison is the baseline visibility
condition--the annual average visibility condition for the period 2000-
2004.\96\
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\94\ 40 CFR 51.308(f)(3)(iii).
\95\ 2019 Guidance, p. 46.
\96\ See 40 CFR 51.308(f)(1)(i), 82 FR 3097-98.
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So that RPGs may also serve as a metric for assessing the amount of
progress a state is making towards the national visibility goal, the
RHR requires states with Class I areas to compare the 2028 RPG for the
most impaired days to the corresponding point on the URP line
(representing visibility conditions in 2028 if visibility were to
improve at a linear rate from conditions in the baseline period of
2000-2004 to natural visibility conditions in 2064). If the most
impaired days RPG in 2028 is above the URP (i.e., if visibility
conditions are improving more slowly than the rate described by the
URP), each state that contributes to visibility impairment in the Class
I area must demonstrate, based on the four-factor analysis required
[[Page 47406]]
under 40 CFR 51.308(f)(2)(i), that no additional emissions reduction
measures would be reasonable to include in its long-term strategy.\97\
To this end, 40 CFR 51.308(f)(3)(ii) requires that each state
contributing to visibility impairment in a Class I area that is
projected to improve more slowly than the URP provide ``a robust
demonstration, including documenting the criteria used to determine
which sources or groups [of] sources were evaluated and how the four
factors required by paragraph (f)(2)(i) were taken into consideration
in selecting the measures for inclusion in its long-term strategy.''
The 2019 Guidance provides suggestions about how such a ``robust
demonstration'' might be conducted.\98\
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\97\ 40 CFR 51.308(f)(3)(ii).
\98\ See 2019 Guidance, pp. 50-51.
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The 2017 RHR, 2019 Guidance, and 2021 Clarifications Memo also
explain that projecting an RPG that is on or below the URP based on
only on-the-books and/or on-the-way control measures (i.e., control
measures already required or anticipated before the four-factor
analysis is conducted) is not a ``safe harbor'' from the CAA's and
RHR's requirement that all states must conduct a four-factor analysis
to determine what emissions reduction measures constitute reasonable
progress. The URP is a planning metric used to gauge the amount of
progress made thus far and the amount left before reaching natural
visibility conditions. However, the URP is not based on consideration
of the four statutory factors and therefore cannot answer the question
of whether the amount of progress being made in any particular
implementation period is ``reasonable progress.'' \99\
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\99\ See 82 FR 3093, 3099-3100; 2019 Guidance, p. 22; 2021
Clarifications Memo, pp. 15-16.
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E. Monitoring Strategy and Other State Implementation Plan Requirements
Section 51.308(f)(6) requires states to have certain strategies and
elements in place for assessing and reporting on visibility. Individual
requirements under this section apply either to states with Class I
areas within their borders, states with no Class I areas but that are
reasonably anticipated to cause or contribute to visibility impairment
in any Class I area, or both. A state with Class I areas within its
borders must submit with its SIP revision a monitoring strategy for
measuring, characterizing, and reporting regional haze visibility
impairment that is representative of all Class I areas within the
state. SIP revisions for such states must also provide for the
establishment of any additional monitoring sites or equipment needed to
assess visibility conditions in Class I areas, as well as reporting of
all visibility monitoring data to the EPA at least annually. Compliance
with the monitoring strategy requirement may be met through a state's
participation in the Interagency Monitoring of Protected Visual
Environments (IMPROVE) monitoring network, which is used to measure
visibility impairment caused by air pollution at the 156 Class I areas
covered by the visibility program.\100\ The IMPROVE monitoring data is
used to determine the 20 percent most anthropogenically impaired and 20
percent clearest sets of days every year at each Class I area and
tracks visibility impairment over time.
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\100\ 40 CFR 51.308(f)(6), (f)(6)(i), (f)(6)(iv).
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All states' SIPs must provide for procedures by which monitoring
data and other information are used to determine the contribution of
emissions from within the state to regional haze visibility impairment
in affected Class I areas.\101\ Section 51.308(f)(6)(v) further
requires that all states' SIPs provide for a statewide inventory of
emissions of pollutants that are reasonably anticipated to cause or
contribute to visibility impairment in any Class I area; the inventory
must include emissions for the most recent year for which data are
available and estimates of future projected emissions. States must also
include commitments to update their inventories periodically. The
inventories themselves do not need to be included as elements in the
SIP revision and are not subject to EPA review as part of the Agency's
evaluation of a SIP revision.\102\ All states' SIP revisions must also
provide for any other elements, including reporting, recordkeeping, and
other measures, that are necessary for states to assess and report on
visibility.\103\ Per the 2019 Guidance, a state may note in its
regional haze SIP revision that its compliance with the in 40 CFR part
51 subpart A satisfies the requirement to provide for an emissions
inventory for the most recent year for which data are available. To
satisfy the requirement to provide estimates of future projected
emissions, a state may explain in its SIP revision how projected
emissions were developed for use in establishing RPGs for its own and
nearby Class I areas.\104\
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\101\ 40 CFR 51.308(f)(6)(ii), (iii).
\102\ See ``Step 8: Additional requirements for regional haze
SIPs'' in 2019 Guidance, p. 55.
\103\ 40 CFR 51.308(f)(6)(vi).
\104\ Id.
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Separate from the requirements related to monitoring for regional
haze purposes under 40 CFR 51.308(f)(6), the RHR also contains a
requirement at 40 CFR 51.308(f)(4) related to any additional monitoring
that may be needed to address visibility impairment in Class I areas
from a single source or a small group of sources. This is called
``reasonably attributable visibility impairment.'' \105\ Under this
provision, if the EPA or the FLM of an affected Class I area has
advised a state that additional monitoring is needed to assess
reasonably attributable visibility impairment, the state must include
in its SIP revision for the second implementation period an appropriate
strategy for evaluating such impairment.
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\105\ The EPA's visibility protection regulations define
``reasonably attributable visibility impairment'' as ``visibility
impairment that is caused by the emission of air pollutants from
one, or a small number of sources.'' 40 CFR 51.301.
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F. Requirements for Periodic Reports Describing Progress Towards the
Reasonable Progress Goals
Section 51.308(f)(5) requires a state's regional haze SIP revision
to address the requirements of paragraphs 40 CFR 51.308(g)(1) through
(5) so that the plan revision due in 2021 will serve also as a progress
report addressing the period since submission of the progress report
for the first implementation period. The regional haze progress report
requirement is designed to inform the public and the EPA about a
state's implementation of its existing long-term strategy and whether
such implementation is in fact resulting in the expected visibility
improvement.\106\ To this end, every state's SIP revision for the
second implementation period is required to describe the status of
implementation of all measures included in the state's long-term
strategy, including BART and reasonable progress emissions reduction
measures from the first implementation period, and the resulting
emissions reductions.\107\
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\106\ See 81 FR 26942, 26950 (May 4, 2016); 82 FR 3119 (January
10, 2017).
\107\ 40 CFR 51.308(g)(1) and (2).
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A core component of the progress report requirements is an
assessment of changes in visibility conditions on the clearest and most
impaired days. For second implementation period progress reports,
section 51.308(g)(3) requires states with Class I areas within their
borders to first determine current visibility conditions for each area
on the most impaired and clearest days,\108\ and then to calculate the
difference between those current conditions and baseline (2000-2004)
visibility conditions to assess progress made to date.\109\ States
[[Page 47407]]
must also assess the changes in visibility impairment for the most
impaired and clearest days since they submitted their first
implementation period progress reports.\110\ Since different states
submitted their first implementation period progress reports at
different times, the starting point for this assessment will vary state
by state.
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\108\ 40 CFR 51.308(g)(3)(i).
\109\ See 40 CFR 51.308(g)(3)(ii).
\110\ See 40 CFR 51.308(g)(3)(iii), (f)(5).
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Similarly, states must provide analyses tracking the change in
emissions of pollutants contributing to visibility impairment from all
sources and activities within the state over the period since they
submitted their first implementation period progress reports.\111\
Changes in emissions should be identified by the type of source or
activity. Section 51.308(g)(5) also addresses changes in emissions
since the period addressed by the previous progress report and requires
states' SIP revisions to include an assessment of any significant
changes in anthropogenic emissions within or outside the state. This
assessment must explain whether these changes in emissions were
anticipated and whether they have limited or impeded progress in
reducing emissions and improving visibility relative to what the state
projected based on its long-term strategy for the first implementation
period.
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\111\ See 40 CFR 51.308(g)(4), (f)(5).
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G. Requirements for State and Federal Land Manager Coordination
CAA section 169A(d) requires that before a state holds a public
hearing on a proposed regional haze SIP revision, it must consult with
the appropriate FLM or FLMs; pursuant to that consultation, the state
must include a summary of the FLMs' conclusions and recommendations in
the notice to the public. Consistent with this statutory requirement,
the RHR also requires that states ``provide the [FLM] with an
opportunity for consultation, in person and at a point early enough in
the State's policy analyses of its long-term strategy emission
reduction obligation so that information and recommendations provided
by the [FLM] can meaningfully inform the State's decisions on the long-
term strategy.'' \112\ Consultation that occurs 120 days prior to any
public hearing or public comment opportunity will be deemed ``early
enough,'' but the RHR provides that in any event the opportunity for
consultation must be provided at least 60 days before a public hearing
or comment opportunity. This consultation must include the opportunity
for the FLMs to discuss their assessment of visibility impairment in
any Class I area and their recommendations on the development and
implementation of strategies to address such impairment.\113\ For the
EPA to evaluate whether FLM consultation meeting the requirements of
the RHR has occurred, the SIP submission should include documentation
of the timing and content of such consultation. The SIP revision
submitted to the EPA must also describe how the state addressed any
comments provided by the FLMs.\114\ Finally, a SIP revision must
provide procedures for continuing consultation between the state and
FLMs regarding the state's visibility protection program, including
development and review of SIP revisions, five-year progress reports,
and the implementation of other programs having the potential to
contribute to impairment of visibility in Class I areas.\115\
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\112\ 40 CFR 51.308(i)(2).
\113\ 40 CFR 51.308(i)(2).
\114\ 40 CFR 51.308(i)(3).
\115\ 40 CFR 51.308(i)(4).
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IV. The EPA's Evaluation of Arizona's Regional Haze Submission for the
Second Implementation Period
A. Background on Arizona's First Implementation Period SIP Submission
Arizona submitted its initial regional haze SIP under 40 CFR 51.308
to the EPA on February 28, 2011 (hereinafter ``2011 Submittal'').\116\
The EPA actions following the 2011 Submittal are outlined in Table 1.
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\116\ On December 23, 2003, ADEQ submitted a Regional Haze plan
under 40 CFR 51.309 (``309 Plan''). Letter dated December 23, 2003,
from Stephen A. Owens, Director, ADEQ, to Wayne Nastri, Regional
Administrator, EPA, Region IX. On December 30, 2004, ADEQ submitted
a revision to its 309 Plan, consisting of rules on emissions trading
and smoke management, and a correction to the State's regional haze
statutes. Letter dated December 30, 2004, from Stephen A. Owens,
Director, ADEQ, to Wayne Nastri, Regional Administrator, EPA. On
December 24, 2008, ADEQ sent a letter resubmitting the 309 Plan
revisions to the EPA. Letter dated December 24, 2008, from Stephen
A. Owens, Director, ADEQ, to Wayne Nastri, Regional Administrator,
EPA. On May 16, 2006 (71 FR 28270) and May 8, 2007 (72 FR 25973),
the EPA approved the smoke management rules that were part of these
submittals. On August 8, 2013 (78 FR 48326), the EPA disapproved the
remainder of the State's submittals under 40 CFR 309.
Table 1--Summary of EPA Actions Under CAA Section 308 on Arizona
Regional Haze in the First Implementation Period
------------------------------------------------------------------------
Date EPA action
------------------------------------------------------------------------
December 5, 2012............ ``Phase 1'' partial approval and partial
disapproval of certain provisions of the
2011 Submittal and promulgation of
partial federal implementation plan
(FIP).\a\
July 30, 2013............... ``Phase 2'' partial approval and partial
disapproval of remaining portions of
Arizona Regional Haze 2011 Submittal.\b\
September 3, 2014........... ``Phase 3'' promulgation of FIP for
remaining portions of Arizona Regional
Haze program.\c\
April 10, 2015.............. Approval of SIP revision for the Arizona
Electric Power Cooperative (AEPCO) Apache
Generating Station.\d\
April 17, 2015.............. FIP revision replacing the control
technology demonstration requirements for
NOX at Lhoist North America of Arizona,
Inc. Nelson Lime Plant with revised
recordkeeping and reporting
requirements.\e\
April 13, 2016.............. FIP revision revising NOX requirements for
the Salt River Project Agricultural
Improvement and Power District (SRP)
Coronado Generating Station.\f\
November 21, 2016........... FIP revision replacing the control
technology demonstration requirements for
NOX at CalPortland Cement (CPC) Rillito
Plant Kiln 4 and Phoenix Cement Company
(PCC) Clarkdale Plant Kiln 4 with revised
recordkeeping and reporting
requirements.\g\
March 27, 2017.............. Approval of SIP revision to replace FIP
for Arizona Public Service (APS) Cholla
Generating Station.\h\
October 10, 2017............ Approval of SIP revision to replace FIP
for the SRP Coronado Generating
Station.\i\
------------------------------------------------------------------------
\a\ 77 FR 72512 (December 5, 2012).
\b\ 78 FR 46142 (July 30, 2013).
\c\ 79 FR 52420 (September 3, 2014).
\d\ 80 FR 19220 (April 10, 2015).
\e\ 80 FR 21176 (April 17, 2015).
\f\ 81 FR 21735 (April 13, 2016).
\g\ 81 FR 83144 (November 21, 2016).
\h\ 82 FR 15139 (March 27, 2017).
[[Page 47408]]
\i\ 82 FR 46903 (October 10, 2017).
On November 12, 2015, the State of Arizona submitted its Progress
Report to meet the requirements of 40 CFR 51.308(g) and (h).\117\ The
EPA approved the Progress Report on July 11, 2019.\118\
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\117\ Letter dated November 12, 2015, from Eric C. Massey,
Director, Air Quality Division, ADEQ, to Jared Blumenfeld, Regional
Administrator, EPA Region IX.
\118\ 84 FR 33002.
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B. Overview of Arizona's Second Implementation Period SIP Submission
In accordance with CAA sections 169A and the RHR at 40 CFR
51.308(f), on August 15, 2022, ADEQ submitted a revision to the Arizona
SIP to address its regional haze obligations for the second
implementation period, which runs through 2028. Arizona made its 2022
Regional Haze Plan submission available for public comment on June 13,
2022. ADEQ received and responded to public comments and included the
comments and responses to those comments in their submission.
The following sections describe Arizona's SIP submission, including
analyses conducted by the WRAP and Arizona, Arizona's assessment of
progress made since the first implementation period in reducing
emissions of visibility impairing pollutants, and the visibility
improvement progress at its Class I areas and nearby Class I areas.
This notice also provides the EPA's evaluation of Arizona's submission
against the requirements of the CAA and RHR for the second
implementation period of the regional haze program.
C. Identification of Class I Areas
Section 169A(b)(2) of the CAA requires each state in which any
Class I area is located or ``the emissions from which may reasonably be
anticipated to cause or contribute to any impairment of visibility'' in
a Class I area to have a plan for making reasonable progress toward the
national visibility goal. The RHR implements this statutory requirement
at 40 CFR 51.308(f), which provides that each state's plan ``must
address regional haze in each mandatory Class I Federal area located
within the State and in each mandatory Class I Federal area located
outside the State that may be affected by emissions from within the
State,'' and (f)(2), which requires each state's plan to include a
long-term strategy that addresses regional haze in such Class I areas.
The EPA explained in the 1999 RHR preamble that the CAA section
169A(b)(2) requirement that states submit SIP revisions to address
visibility impairment establishes ``an `extremely low triggering
threshold' in determining which States should submit SIPs for regional
haze.'' \119\ In concluding that each of the contiguous 48 states and
the District of Columbia meet this threshold,\120\ the EPA relied on
``a large body of evidence demonstrat[ing] that long-range transport of
fine PM contributes to regional haze,'' \121\ including modeling
studies that ``preliminarily demonstrated that each State not having a
Class I area had emissions contributing to impairment in at least one
downwind Class I area.'' \122\ In addition to the technical evidence
supporting a conclusion that each state contributes to existing
visibility impairment, the EPA also explained that the second half of
the national visibility goal--preventing future visibility impairment--
requires having a framework in place to address future growth in
visibility-impairing emissions and makes it inappropriate to
``establish criteria for excluding States or geographic areas from
consideration as potential contributors to regional haze visibility
impairment.'' \123\ Thus, the EPA concluded that the agency's
``statutory authority and the scientific evidence are sufficient to
require all States to develop regional haze SIPs to ensure the
prevention of any future impairment of visibility, and to conduct
further analyses to determine whether additional control measures are
needed to ensure reasonable progress in remedying existing impairment
in downwind Class I areas.'' \124\ The EPA's 2017 revisions to the RHR
did not disturb this conclusion.\125\
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\119\ 64 FR 35721.
\120\ The EPA determined that ``there is more than sufficient
evidence to support our conclusion that emissions from each of the
48 contiguous states and the District of Columba may reasonably be
anticipated to cause or contribute to visibility impairment in a
Class I area.'' 64 FR at 35721. Hawaii, Alaska, and the U.S. Virgin
Islands must also submit regional haze SIPs because they contain
Class I areas.
\121\ Id.
\122\ Id. at 35722.
\123\ Id. at 35721.
\124\ Id. at 35722.
\125\ See 82 FR 3094.
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Arizona has 12 Class I areas within its borders: the Chiricahua
National Monument, Chiricahua Wilderness Area, Galiuro Wilderness Area,
Grand Canyon National Park, Mazatzal Wilderness Area, Mount Baldy
Wilderness Area, Petrified Forest National Park, Pine Mountain
Wilderness, Saguaro National Park,\126\ Sierra Ancha Wilderness Area,
Superstition Wilderness Area, and Sycamore Canyon Wilderness Area.
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\126\ Saguaro National Park was originally established in 1933
as a National Monument. In 1976, portions of Saguaro National
Monument were designated as a Wilderness Area, and the Saguaro
Wilderness Area was designated as a Mandatory Class I area in 1979.
44 FR 69124 (November 30, 1979). Congress officially elevated the
area known as Saguaro National Monument to the current designation
as a National Park in 1994.
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Arizona did not expressly identify within its SIP which Class I
Federal areas located outside of Arizona may be affected by emissions
from within Arizona. However, as part of its source selection process
described in Chapter 8 and Appendix C, Section C2 of the 2022 Arizona
Regional Haze Plan, Arizona included the Q/d \127\ values associated
with Class I areas outside the State. Further, ADEQ reviewed the source
apportionment results of the ``On the Books'' (``2028OTBa2'')
projections scenario from the WRAP Regional Haze photochemical grid
modeling platform.\128\ ADEQ participated in interstate consultation
with California, Utah, Nevada, Colorado, and New Mexico, which included
discussion of the WRAP modeling and source apportionment products.\129\
For New Mexico specifically, ADEQ also provided WRAP regional modeling
platform source apportionment results for the 20 percent most impaired
days at the four Class I areas in New Mexico that are closest to
Arizona.\130\
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\127\ Q/d represents a source's annual emissions in tons (Q)
divided by the distance in kilometers (d) between the source and the
nearest Class I area. For regional haze purposes, only primary
visibility-impairing pollutants were included in a source's total Q:
NO<INF>X</INF>, SO<INF>2</INF>, and PM<INF>10</INF>.
\128\ 2022 Arizona Regional Haze Plan, Chapter 7.4 and Appendix
D. The Particle Source Apportionment Technology (PSAT) tool was
applied at a regional level to separate U.S. anthropogenic
contributions from those of fire, natural, and international
anthropogenic contributions for a current period and a future year
in 2028.
\129\ Id. at Chapter 2.6.
\130\ Id. at Table 2-3.
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As explained above, the EPA concluded in the 1999 RHR that ``all
[s]tates contain sources whose emissions are reasonably anticipated to
contribute to regional haze in a Class I area,'' \131\ and this
determination was not changed in the 2017 RHR. Critically, the statute
and regulation both require that the cause-or-contribute assessment
consider all emissions of visibility-impairing pollutants from a state,
as opposed to emissions of a particular pollutant or emissions from a
certain set
[[Page 47409]]
of sources. Consistent with these requirements, the 2019 Guidance makes
it clear that ``all types of anthropogenic sources are to be included
in the determination'' of whether a state's emissions are reasonably
anticipated to result in any visibility impairment.\132\ As explained
in Section IV.E.2 of this document, we are proposing to find that the
2022 Arizona Regional Haze Plan did not fully meet the requirements of
40 CFR 51.308(f)(2) related to the development of a long-term strategy.
Although the State's failure to identify specific out-of-state Class I
areas is not the basis for this proposed disapproval, we recommend that
ADEQ more clearly identify which out-of-state Class I areas may be
affected by emissions from Arizona.
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\131\ 64 FR at 35721.
\132\ 2019 Guidance, p. 8.
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D. Calculations of Baseline, Current, and Natural Visibility
Conditions; Progress to Date; and the Uniform Rate of Progress
Section 51.308(f)(1) requires states to determine the following for
``each mandatory Class I Federal area located within the State'':
baseline visibility conditions for the most impaired and clearest days,
natural visibility conditions for the most impaired and clearest days,
progress to date for the most impaired and clearest days, the
differences between current visibility conditions and natural
visibility conditions, and the URP. This section also provides the
option for states to propose adjustments to the URP line for a Class I
area to account for visibility impacts from anthropogenic sources
outside the United States and/or the impacts from wildland prescribed
fires that were conducted for certain, specified objectives.\133\
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\133\ 40 CFR 51.308(f)(1)(vi)(B).
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In the 2022 Arizona Regional Haze Plan, ADEQ used visibility data
from IMPROVE monitoring sites for 2000-2004 for baseline
visibility.\134\ ADEQ also obtained visibility data from IMPROVE
monitoring data for 2005-2019. The five-year average of 2015-2019
represents current visibility conditions. ADEQ also determined natural
visibility by estimating the natural concentrations of visibility-
impairing pollutants and then calculating total light extinction with
the IMPROVE algorithm. Comparison of baseline conditions to natural
visibility conditions shows the improvement necessary to attain natural
visibility by 2064 measured in deciviews of improvement per year that
represents the URP. The calculations of baseline, current, and natural
visibility conditions, as well as the progress to date, differences
between current visibility conditions and natural visibility
conditions, and the URP for each of the state's Class I areas can be
found in Chapter 5.2 of the 2022 Arizona Regional Haze Plan. The URP
glidepaths and 2028 visibility projections are discussed further in
Section 7 and Appendix D. A summary of Arizona's visibility conditions
and unadjusted URPs is also presented in Table 2 of this document. A
summary of Arizona's adjusted URPs is presented in Table 21 of this
document.
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\134\ 2022 Arizona Regional Haze Plan, Chapter 5.
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Data for the Chiricahua National Monument, Chiricahua Wilderness
Area, and the Galiuro Wilderness Area come from the CHIR1 monitoring
site.\135\ These three Class I areas have 2000-2004 baseline visibility
conditions of 4.9 deciviews on the 20 percent clearest days and 10.5
deciviews on the 20 percent most impaired days. ADEQ calculated an
estimated natural background visibility of 1.8 deciviews on the 20
percent clearest days and 4.9 deciviews on the 20 percent most impaired
days for these three Class I areas. The current visibility conditions,
which are based on 2015-2019 monitoring data, were 3.9 deciviews on the
clearest days and 9.5 deciviews on the most impaired days, which are
2.1 deciviews and 4.6 deciviews greater than natural conditions on the
respective sets of days. The progress to date, subtracting current
conditions from baseline conditions, yields a 1.1 deciview improvement
for the 20 percent clearest days and 1.0 deciview improvement for the
20 percent most impaired days. ADEQ calculated an annual URP of 0.09
deciviews per year needed to reach natural visibility on the 20 percent
most impaired days by 2064. ADEQ also indicates that the visibility
improvement needed to maintain the URP from the baseline to 2028 is 2.2
deciviews.
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\135\ Figure 5-2 in the 2022 Arizona Regional Haze Plan depicts
the annual and 5-year average most impaired day and clearest day
visibility in deciviews (dv), the unadjusted MID URP, and the
clearest days threshold for the CHIR1 site.
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Data for the Grand Canyon National Park come from the GRCA2
site.\136\ The Grand Canyon has 2000-2004 baseline visibility
conditions of 2.2 deciviews on the 20 percent clearest days and 8
deciviews on the 20 percent most impaired days. ADEQ calculated an
estimated natural background visibility of 0.3 deciviews on the 20
percent clearest days and 4.2 deciviews on the 20 percent most impaired
days for these three Class I areas. The current visibility conditions,
which are based on 2015-2019 monitoring data, were 1.6 deciviews on the
clearest days and 6.9 deciviews on the most impaired days, which are
1.3 deciviews and 2.7 deciviews greater than natural conditions on the
respective sets of days. The progress to date, subtracting current
conditions from baseline conditions, yields a 0.6 deciview improvement
for the 20 percent clearest days and 1.1 deciview improvement for the
20 percent most impaired days. ADEQ calculated an annual URP of 0.06
deciviews per year needed to reach natural visibility on the 20 percent
most impaired days by 2064. ADEQ also indicates that the visibility
improvement needed to maintain the URP from the baseline to 2028 is 1.5
deciviews.
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\136\ Figure 5-3 in the 2022 Arizona Regional Haze Plan depicts
the annual and 5-year average most impaired day and clearest day
visibility in dv, the unadjusted MID URP, and the clearest days
threshold for the GRCA2 site.
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Data for the Mazatzal Wilderness Area and Pine Mountain Wilderness
Area come from the IKBA1 monitoring site.\137\ These two Class I areas
have 2000-2004 baseline visibility conditions of 5.4 deciviews on the
20 percent clearest days and 11.2 deciviews on the 20 percent most
impaired days. ADEQ calculated an estimated natural background
visibility of 1.9 deciviews on the 20 percent clearest days and 5.2
deciviews on the 20 percent most impaired days for these two Class I
areas. The current visibility conditions, which are based on 2015-2019
monitoring data, were 4.2 deciviews on the clearest days and 9.5
deciviews on the most impaired days, which are 2.3 deciviews and 4.3
deciviews greater than natural conditions on the respective sets of
days. The progress to date, subtracting current conditions from
baseline conditions, yields a 1.2 deciview improvement for the 20
percent clearest days and 1.7 deciview improvement for the 20 percent
most impaired days. ADEQ calculated an annual URP of 0.10 deciviews per
year needed to reach natural visibility on the 20 percent most impaired
days by 2064. ADEQ indicates that the visibility improvement needed to
maintain the URP from the baseline to 2028 is 2.4 deciviews.
---------------------------------------------------------------------------
\137\ Figure 5-4 in the 2022 Arizona Regional Haze Plan depicts
the annual and 5-year average most impaired day and clearest day
visibility (dv), the unadjusted MID URP, and the clearest days
threshold for the IKBA1 site.
---------------------------------------------------------------------------
Data for the Mount Baldy Wilderness Area come from the BALD1
monitoring
[[Page 47410]]
site.\138\ Mount Baldy has 2000-2004 baseline visibility conditions of
3.0 deciviews on the 20 percent clearest days and 8.8 deciviews on the
20 percent most impaired days. ADEQ calculated an estimated natural
background visibility of 0.5 on the 20 percent clearest days and 4.2
deciviews on the 20 percent most impaired days. The current visibility
conditions, which are based on 2015-2019 monitoring data, were 1.8
deciviews on the clearest days and 7.3 deciviews on the most impaired
days, which are 1.3 deciviews and 3.1 deciviews greater than natural
conditions on the respective sets of days. The progress to date,
subtracting current conditions from baseline conditions, yields a 1.2
deciview improvement for the 20 percent clearest days and 1.5 deciview
improvement for the 20 percent most impaired days. ADEQ calculated an
annual URP of 0.08 deciviews per year needed to reach natural
visibility on the 20 percent most impaired days by 2064. ADEQ indicates
that the visibility improvement needed to maintain the URP from the
baseline to 2028 is 1.8 deciviews.
---------------------------------------------------------------------------
\138\ 2022 Arizona Regional Haze Plan, Tables 5-1 through 5-3.
---------------------------------------------------------------------------
Data for the Petrified Forest National Park come from the PEFO1
monitoring site.\139\ The Class I area has 2000-2004 baseline
visibility conditions of 5.0 deciviews on the 20 percent clearest days
and 9.8 deciviews on the 20 percent most impaired days. ADEQ calculated
an estimated natural background visibility of 1.1 deciviews on the 20
percent clearest days and 4.2 deciviews on the 20 percent most impaired
days. The current visibility conditions, which are based on 2015-2019
monitoring data, were 3.3 deciviews on the clearest days and 8.1
deciviews on the most impaired days, which are 2.2 deciviews and 3.9
deciviews greater than natural conditions on the respective sets of
days. The progress to date, subtracting current conditions from
baseline conditions, yields a 1.8 deciview improvement for the 20
percent clearest days and 1.7 deciview improvement for the 20 percent
most impaired days. ADEQ calculated an annual URP of 0.09 deciviews per
year needed to reach natural visibility on the 20 percent most impaired
days by 2064. ADEQ indicates that the visibility improvement needed to
maintain the URP from the baseline to 2028 is 2.4 deciviews.
---------------------------------------------------------------------------
\139\ Figure 5-5 in the 2022 Arizona Regional Haze Plan depicts
the annual and 5-year average most impaired day and clearest day
visibility in dv, the unadjusted MID URP, and the clearest days
threshold for the PEFO1 site.
---------------------------------------------------------------------------
Data for the Saguaro National Park come from the SAGU1 monitoring
site.\140\ The Class I area has 2000-2004 baseline visibility
conditions of 6.9 deciviews on the 20 percent clearest days and 12.6
deciviews on the 20 percent most impaired days. ADEQ calculated an
estimated natural background visibility of 2.2 deciviews on the 20
percent clearest days and 5.1 deciviews on the 20 percent most impaired
days. The current visibility conditions, which are based on 2015-2019
monitoring data, were 5.8 deciviews on the clearest days and 10.7
deciviews on the most impaired days, which are 3.6 deciviews and 5.6
deciviews greater than natural conditions on the respective sets of
days. The progress to date, subtracting current conditions from
baseline conditions, yields a 1.1 deciview improvement for the 20
percent clearest days and 1.9 deciview improvement for the 20 percent
most impaired days. ADEQ calculated an annual URP of 0.12 deciviews per
year needed to reach natural visibility on the 20 percent most impaired
days by 2064. ADEQ indicates that the visibility improvement needed to
maintain the URP from the baseline to 2028 is 3.0 deciviews.
---------------------------------------------------------------------------
\140\ Figure 5-6 in the 2022 Arizona Regional Haze Plan depicts
the annual and 5-year average most impaired day and clearest day
visibility in dv, the unadjusted MID URP, and the clearest days
threshold for the SAGU1 site.
---------------------------------------------------------------------------
Data for the Sierra Ancha Wilderness Area come from the SIAN1
monitoring site.\141\ The Class I area has 2000-2004 baseline
visibility conditions of 6.2 deciviews on the 20 percent clearest days
and 10.8 deciviews on the 20 percent most impaired days. ADEQ
calculated an estimated natural background visibility of 2.0 deciviews
on the 20 percent clearest days and 5.1 deciviews on the 20 percent
most impaired days. The current visibility conditions, which are based
on 2015-2019 monitoring data, were 4.3 deciviews on the clearest days
and 9.4 deciviews on the most impaired days, which are 2.3 deciviews
and 4.3 deciviews greater than natural conditions on the respective
sets of days. The progress to date, subtracting current conditions from
baseline conditions, yields a 1.9 deciview improvement for the 20
percent clearest days and 1.4 deciview improvement for the 20 percent
most impaired days. ADEQ calculated an annual URP of 0.09 deciviews per
year needed to reach natural visibility on the 20 percent most impaired
days by 2064. ADEQ indicates that the visibility improvement needed to
maintain the URP from the baseline to 2028 is 2.3 deciviews.
---------------------------------------------------------------------------
\141\ Figure 5-7 in the 2022 Arizona Regional Haze Plan depicts
the annual and 5-year average most impaired day and clearest day
visibility in dv, the unadjusted MID URP, and the clearest days
threshold for the SIAN1 site. Data is not available for 2016-2020
for SIAN1.
---------------------------------------------------------------------------
Data for the Superstition Wilderness Area come from the TONT1
monitoring site.\142\ The Class I area has 2000-2004 baseline
visibility conditions of 6.5 deciviews on the 20 percent clearest days
and 11.7 deciviews on the 20 percent most impaired days. ADEQ
calculated an estimated natural background visibility of 2.0 deciviews
on the 20 percent clearest days and 5.1 deciviews on the 20 percent
most impaired days. The current visibility conditions, which are based
on 2015-2019 monitoring data, were 4.9 deciviews on the clearest days
and 10.3 deciviews on the most impaired days, which are 2.9 deciviews
and 5.2 deciviews greater than natural conditions on the respective
sets of days. The progress to date, subtracting current conditions from
baseline conditions, yields a 1.6 deciview improvement for the 20
percent clearest days and 1.3 deciview improvement for the 20 percent
most impaired days. ADEQ calculated an annual URP of 0.09 deciviews per
year needed to reach natural visibility on the 20 percent most impaired
days by 2064. ADEQ indicates that the visibility improvement needed to
maintain the URP from the baseline to 2028 is 2.6 deciviews.
---------------------------------------------------------------------------
\142\ Figure 5-8 in the 2022 Arizona Regional Haze Plan depicts
the annual and 5-year average most impaired day and clearest day
visibility in dv, the unadjusted MID URP, and the clearest days
threshold for the TONT1 site.
---------------------------------------------------------------------------
Data for the Sycamore Canyon Wilderness Area come from the
SYCA_RHTS monitoring site.\143\ The Class I area has 2000-2004 baseline
visibility conditions of 5.6 deciviews on the 20 percent clearest days
and 12.2 deciviews on the 20 percent most impaired days. ADEQ
calculated an estimated natural background visibility of 1.0 deciview
on the 20 percent clearest days and 4.7 deciviews on the 20 percent
most impaired days. The current visibility conditions, which are based
on 2015-2019 monitoring data, were 3.9 deciviews on the clearest days
and 11.7 deciviews on the most impaired days, which are 2.9 deciviews
and 7.0 deciviews greater than natural
[[Page 47411]]
conditions on the respective sets of days. The progress to date,
subtracting current conditions from baseline conditions, yields a 1.6
deciview improvement for the 20 percent clearest days and 0.4 deciview
improvement for the 20 percent most impaired days. ADEQ calculated an
annual URP of 0.12 deciviews per year needed to reach natural
visibility on the 20 percent most impaired days by 2064. ADEQ indicates
that the visibility improvement needed to maintain the URP from the
baseline to 2028 is 3.0 deciviews.
---------------------------------------------------------------------------
\143\ Figure 5-9 in the 2022 Arizona Regional Haze Plan depicts
the annual and 5-year average most impaired day and clearest day
visibility in dv, the unadjusted MID URP, and the clearest days
threshold for the SYCA_RHTS site. The abbreviation ``SYCA_RHTS'' is
for Sycamore Regional Haze Tracking Site, and combines data from the
SYCA1 IMPROVE site, which closed in 2015 during the baseline period,
and data from the newer SYCA2 site.
Table 2--Visibility Conditions and Uniform Rate of Progress, in Deciviews (dv)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
20% Clearest days 20% Most-impaired days Maintain URP
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
total dv total dv
Class I Area Baseline Current Natural Difference Baseline Current Natural Difference dv per year (baseline (baseline
to 2019) to 2028)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Chiricahua NM WA............................................. 4.9 3.9 1.8 2.1 10.5 9.5 4.9 4.6 0.09 1.4 2.2
Chiricahua WA................................................ 4.9 3.9 1.8 2.1 10.5 9.5 4.9 4.6 0.09 1.4 2.2
Galiuro WA................................................... 4.9 3.9 1.8 2.1 10.5 9.5 4.9 4.6 0.09 1.4 2.2
Grand Canyon NP.............................................. 2.2 1.6 0.3 1.3 8.0 6.9 4.2 2.7 0.06 1.0 1.5
Mazatzal WA.................................................. 5.4 4.2 1.9 2.3 11.2 9.5 5.2 4.3 0.10 1.5 2.4
Mount Baldy WA............................................... 3.0 1.8 0.5 1.3 8.8 7.3 4.2 3.1 0.08 1.2 1.8
Petrified Forest NP.......................................... 5.0 3.3 1.1 2.2 9.8 8.1 4.2 3.9 0.09 1.4 2.2
Pine Mountain WA............................................. 5.4 4.2 1.9 2.3 11.2 9.5 5.2 4.3 0.10 1.5 2.4
Saguaro NP................................................... 6.9 5.8 2.2 3.6 12.6 10.7 5.1 5.6 0.12 1.9 3.0
Sierra Ancha WA.............................................. 6.2 4.3 2.0 2.3 10.8 9.4 5.1 4.3 0.09 1.2 2.3
Superstition WA.............................................. 6.5 4.9 2.0 2.9 11.7 10.3 5.1 5.2 0.11 1.6 2.6
Sycamore Canyon WA........................................... 5.6 3.9 1.0 2.9 12.2 11.7 4.7 7.0 0.12 1.9 3.0
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Source: 2022 Arizona Regional Haze Plan, p. 38, Tables 5-1, 5-2, and 5-3. Baseline conditions are for 2000-2004 Current Conditions are for 2015-2019; Difference is Current dv minus Natural
Conditions. Maintain URP shows the deciviews per year and the total deciview improvements needed to maintain the Uniform Rate of Progress to 2019 and 2028.
ADEQ chose to adjust its URP to account for international
anthropogenic impacts and for the impacts of wildland prescribed fires.
The WRAP/WAQS Regional Haze modeling platform used scaled 2014 NEI
wildland prescribed fire data for purposes of calculating the URP
adjustments. ADEQ submits activity data related to wildland prescribed
fires approved under its SIP approved Enhanced Smoke Management Program
to the EPA for use in the development of the NEI. WRAP used the results
from the CAMx 2028OTBa2 High-Level Source Apportionment run to obtain
concentrations due to international emissions and to prescribed fire.
These concentrations were then used in a relative sense to estimate the
contributions for use in adjusting the URP. That is, the modeled
relative effect of removing their emissions (relative response factors)
was applied to projections of 2028 concentrations. The resulting
concentration decrease was taken as the contribution of these sources.
The international and prescribed fire contributions were therefore
calculated in a fashion consistent with each other and with the 2028
projections. This approach is consistent with the default method
described in the EPA's September 2019 regional haze modeling Technical
Support Document (``EPA 2019 Modeling TSD'') \144\ and with the source
apportionment approach described in EPA's 2018 Visibility Tracking
Guidance.\145\ Two different adjusted glidepath options,
``International Emissions Only (A)'' and ``International Emissions +
Wildland Rx Fire (B),'' were made available on the WRAP TSS to adjust
the URP glidepath end points projections at 2064 for Class I federal
areas on the most impaired days. ADEQ used the International Emissions
+ Wildland Rx Fire glidepath endpoint adjustment option. The choice of
adjustment option made a negligible difference for five of the nine
IMPROVE monitor locations, a small difference for three others, and a
larger difference for the SYCA_RHTS monitor covering the Sycamore
Canyon Wilderness. The deciview values for the URP glidepaths, both
unadjusted and adjusted, were fairly close to values estimated in the
EPA 2019 Modeling TSD. The choice of adjustment option made no
difference in whether the RPG for each area was above or below its URP
glidepath, which is discussed in the Section IV.F of this document.
---------------------------------------------------------------------------
\144\ Memorandum from Richard A. Wayland, Director, Air Quality
Assessment Division, EPA, to Regional Air Division Directors,
Subject: ``Availability of Modeling Data and Associated Technical
Support Document for the EPA's Updated 2028 Visibility Air Quality
Modeling,'' September 19, 2019, available at <a href="https://www.epa.gov/visibility/technical-support-document-epas-updated-2028-regional-haze-modeling">https://www.epa.gov/visibility/technical-support-document-epas-updated-2028-regional-haze-modeling</a>.
\145\ Memorandum from Richard A. Wayland, Director, Air Quality
Assessment Division, EPA, to Regional Air Division Directors,
Subject: ``Technical Guidance on Tracking Visibility Progress for
the Second Implementation Period of the Regional Haze Program,''
December 20, 2018, available at <a href="https://www.epa.gov/sites/default/files/2018-12/documents/technical_guidance_tracking_visibility_progress.pdf">https://www.epa.gov/sites/default/files/2018-12/documents/technical_guidance_tracking_visibility_progress.pdf</a>.
---------------------------------------------------------------------------
The EPA is therefore proposing to find that Chapter 5 and Appendix
A of the 2022 Arizona Regional Haze Plan meet the requirements of 40
CFR 51.308(f)(1) related to the calculations of baseline, current, and
natural visibility conditions; progress to date; differences between
current visibility conditions and natural visibility conditions; and
the URPs for the second implementation period. We also propose to find
that ADEQ has estimated the impacts from anthropogenic sources outside
the United States and wildland prescribed fires using scientifically
valid data and methods, and we therefore propose to approve the
adjustments to the URPs pursuant to 40 CFR 51.308(f)(1)(vi)(B).
E. Long-Term Strategy for Regional Haze
1. Arizona's Long-Term Strategy in the 2022 Arizona Regional Haze Plan
Each state having a Class I area within its borders or emissions
that may affect visibility in a Class I area must develop a long-term
strategy for making reasonable progress towards the national visibility
goal. As explained in Section 3 of this notice, reasonable progress is
achieved when all states contributing to visibility impairment in
[[Page 47412]]
a Class I area are implementing the measures determined--through
application of the four statutory factors to sources of visibility
impairing pollutants--to be necessary to make reasonable progress.\146\
Each state's long-term strategy must include the enforceable emissions
limitations, compliance schedules, and other measures that are
necessary to make reasonable progress.\147\ All new (i.e., additional)
measures that are the outcome of four-factor analyses are necessary to
make reasonable progress and must be in the long-term strategy. If the
outcome of a four-factor analysis and analysis of other measures
necessary to make reasonable progress is that no new measures are
reasonable for a source, that source's existing measures are necessary
to make reasonable progress, unless the state can demonstrate that the
source will continue to implement those measures and will not increase
its emissions rate. Existing measures that are necessary to make
reasonable progress must also be in the long-term strategy. In
developing its long-term strategies, a state must also consider the
five additional factors in section 51.308(f)(2)(iv). As part of its
reasonable progress determinations, the state must describe the
criteria used to determine which sources or group of sources were
evaluated in a four-factor analysis for the second implementation
period and how the four factors were taken into consideration in
selecting the emissions reduction measures for inclusion in the long-
term strategy.\148\
---------------------------------------------------------------------------
\146\ 40 CFR 51.308(f)(2)(i).
\147\ 40 CFR 51.308(f)(2).
\148\ 40 CFR 51.308(f)(2)(iii).
---------------------------------------------------------------------------
The consultation requirements of section 51.308(f)(2)(ii) provide
that states must consult with other states that are reasonably
anticipated to contribute to visibility impairment in a Class I area to
develop and coordinate emissions management strategies containing the
emissions reduction measures that are necessary to make reasonable
progress. Section 51.308(f)(2)(ii)(A) and (B) require states to
consider the emissions reduction measures identified by other states as
necessary for reasonable progress and to include agreed upon measures
in their SIPs, respectively. Section 51.308(f)(2)(ii)(C) speaks to what
happens if states cannot agree on what measures are necessary to make
reasonable progress.
The following sections summarize Arizona's long-term strategy for
the second planning period, as set forth in the 2022 Arizona Regional
Haze Plan. The EPA's evaluation with respect to the requirements of
51.308(f)(2) is provided in Section IV.E.2.
a. Point Sources
i. Source Selection
PM is composed of different chemical constituents, including
sulfates, nitrates, organic carbon, elemental carbon, coarse mass, and
soil dust (``PM species'' or ``species''). ADEQ focused its source
evaluation on the PM species that dominate visibility impairment at its
Class I areas.\149\ ADEQ evaluated light extinction for PM species by
calculating total light extinction \150\ and anthropogenic extinction
\151\ for each species on the most impaired days at its Class I areas.
ADEQ indicated that when the anthropogenic portion of the impact is
considered, the sulfate, nitrate, and coarse mass species collectively
constitute 80 percent of total extinction on average across the Arizona
Class I areas (ranging from 72.3 percent at the PEFO1 monitor to 88.8
percent at the CHIR1 monitor).\152\ ADEQ also noted that, while organic
carbon mass and light absorbing carbon account for more than 10 percent
of the anthropogenic light extinction impact for at least one of the
Class I areas, the emissions that contribute to these species are
primarily from biogenic, wildfires, and onroad sources, for which the
State has limited available control opportunities. Based on this
analysis, ADEQ determined that sulfate, nitrate, and coarse mass are
the three species that should be evaluated for source controls during
this planning period in order to maximize the visibility benefit of
controls. SO<INF>2</INF> emissions are a precursor to the formation of
sulfate, and NO<INF>X</INF> emissions are a precursor to the formation
of nitrate. Coarse mass emissions involve particulates with an
aerodynamic diameter between 10 and 2.5 microns (i.e., PM<INF>10</INF>
less PM<INF>2.5</INF>). Because coarse mass is not commonly included in
emissions inventories, states generally use particulate matter with an
aerodynamic diameter under 10 microns (PM<INF>10</INF>) as a surrogate
for coarse mass. Therefore, ADEQ conducted its screening based on
NO<INF>X</INF>, SO<INF>2</INF>, and PM<INF>10</INF> emissions.
---------------------------------------------------------------------------
\149\ 2022 Arizona Regional Haze Plan, Section 8.2.1.
\150\ Id., Appendix C, Table 3.
\151\ Id. at Table 4.
\152\ Id. at Table 5.
---------------------------------------------------------------------------
Arizona used the Q/d method to identify sources that are reasonably
expected to contribute to visibility impairment at any Class I area.
ADEQ used a Q/d threshold of 10 (combined NO<INF>X</INF>,
SO<INF>2</INF> and PM<INF>10</INF> emissions) based on the 2014
National Emissions Inventory (NEI) Version 2 (``2014v2'') emissions.
ADEQ's approach included additional steps in order to screen out
processes within the identified sources that have installed or will
install ``effective controls'' prior to the end of the second planning
period.\153\ ADEQ evaluated 2018 operational and emissions data to
determine which processes have an effective control installed or
incorporated within the last five years or will install or incorporate
an effective control prior to 2028.\154\
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\153\ A full description of the methodology and determinations
of effective controls and their treatment are included in Appendix C
of the 2022 Arizona Regional Haze Plan. Figure 8-1 of the 2022
Arizona Regional Haze Plan presents a flowchart of ADEQ's major
point source screening process.
\154\ Arizona Regional Haze Plan, Appendix C, Section C2.2.1.2.
---------------------------------------------------------------------------
ADEQ used following the criteria for determining what constitutes
an effective control: (1) the control was installed within the last
five years of this analysis (i.e., during or since 2014) or will be
installed prior to 2028; (2) the control was installed to meet (a) PSD
requirements (or is otherwise considered a to be equivalent to the best
available control technology (BACT)), (b) BART requirements (including
BART reconsiderations and better-than-BART determinations),\155\ (c)
Regional Haze 1st planning period Reasonable Progress, requirements, or
(d) other SIP requirements to achieve NAAQS compliance; and (3) process
emissions must be controlled through routing those emissions through a
newly constructed or recently upgraded pollution control device or
``taking emission limits that would otherwise equate to the
installation of a pollution control device.'' \156\
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\155\ Pursuant to 40 CFR 51.308(e)(2), States have the
flexibility to adopt alternatives that provide greater reasonable
progress towards natural visibility conditions than BART for one or
more subject-to-BART sources (commonly known as ``better-than-BART''
alternatives).
\156\ Arizona Regional Haze Plan Appendix C, p. 30.
---------------------------------------------------------------------------
ADEQ further determined that the application of the effective
control screening should be applied at the process level as opposed to
the facility-wide level. Given an increase in resolution at the process
level as compared to the unit level, ADEQ determined that examining
facility processes was the most appropriate level of resolution for
determining which emission sources at a facility would undergo a four-
factor control determination. Additionally, given that some permitted
sources submit emissions inventories containing hundreds of processes,
including many that emit low levels of pollutants, ADEQ
[[Page 47413]]
determined that it was unnecessary to perform a control evaluation on
all processes at each facility, but that at least the largest 80
percent of pollutant- and process-specific emissions at a source should
be considered.
As shown in Table 3 of this document, ADEQ determined that 55
processes within the identified sources were effectively
controlled.\157\ These include certain processes where no control has
been installed within the last five years, but where new emissions
limits were established, such as Tucson Electric Power (TEP) Company
Irvington Generating Station (IGS) Unit 4 and AEPCO Apache Generating
Station Unit 2, both of which converted from coal to natural gas as
part of better-than-BART alternatives during the first planning period.
ADEQ then screened out these effectively controlled processes from
further consideration and indicated that these effectively controlled
processes will be reevaluated in future rounds of Regional Haze
planning.
---------------------------------------------------------------------------
\157\ Id. at Exhibit CI.
Table 3--List of Effective Controls Identified by ADEQ for Arizona Major Point Sources
----------------------------------------------------------------------------------------------------------------
Unit/process
Facility description Control program Comments
----------------------------------------------------------------------------------------------------------------
AEPCO--Apache Generating Steam Unit 1 Gas. Regional Haze-- NOX limit of 0.056 pounds per million
Station. BART Alternative. British thermal unit (lb/MMBtu)
standalone and 0.1 lb/MMBtu combined ST1/
GT1 and a 30-calendar day average of
1,205 lb/day, PM10 limit of 0.0075 lb/
MMBtu, and SO2 limit of 0.00064 lb/MMBtu.
AEPCO--Apache Generating Steam Unit 2 Gas. Regional Haze-- Conversion from coal to natural gas with
Station. BART Alternative. NOX limit of 0.085 lb/MMBtu 30-day
average, SO2 limit of 0.00064 lb/MMBtu 30-
day average, PM10 limit of 0.008 lb/MMBtu
30-day average.
AEPCO--Apache Generating Steam Unit 2 Coal Regional Haze-- Conversion from coal to natural gas w/NOX
Station. BART Alternative. limit of 0.085 lb/MMBtu 30-day average,
SO2 limit of 0.00064 lb/MMBtu 30-day
average, PM10 limit of 0.008 lb/MMBtu 30-
day average.
AEPCO--Apache Generating Steam Unit 3 Coal Regional Haze-- Selective non-catalytic reduction (SNCR)
Station. BART Alternative. installation w/a NOX 30-day average limit
of 0.23 lb/MMBtu.
AEPCO--Apache Generating Steam Unit 3 Gas. Regional Haze-- SNCR installation w/a NOX 30-day average
Station. BART Alternative. limit of 0.23 lb/MMBtu.
AEPCO--Apache Generating Gas Combust Regional Haze-- NOX limit of 0.056 lb/MMBtu standalone and
Station. Turbine #1. BART Alternative. 0.1 lb/MMBtu combined ST1/GT1 and a 30-
calendar day average of 1,205 lb/day,
PM10 limit of 0.0075 lb/MMBtu, and SO2
limit of 0.00064 lb/MMBtu.
APS--Cholla Power Plant....... Coal Combustion Regional Haze-- Cease operation or convert unit from coal
In Steam Unit #1. BART. to natural gas by April 30, 2025, with
20% annual capacity factor.
APS--Cholla Power Plant....... Coal Combustion Regional Haze-- Permanently shut down April 1, 2016.
in Steam Unit #2. BART.
APS--Cholla Power Plant....... Coal Combustion Regional Haze-- Permanently cease coal burning by April
in Steam Unit #3. BART. 30, 2025. Natural gas option with less
than 20% average annual capacity factor
(NOX, SO2, and PM10 emissions limits
specified).
APS--Cholla Power Plant....... Coal Combustion Regional Haze-- Permanently cease coal burning by April
in Steam Unit #4. BART. 30, 2025. Natural gas option with less
than 20% average annual capacity factor
(NOX, SO2, and PM10 emissions limits
specified).
Asarco--Hayden Smelter........ Flash Furnace, SIP Action--Pb, Converter retrofit & HSA Lime Injection/
Converter. SO2. Baghouse.
Asarco--Hayden Smelter........ Paved Road SIP Action--Pb... Limits on Lead Bearing Fugitive Dust from
Traffic. the Hayden smelter.
Asarco--Hayden Smelter........ Product Dryer SIP Action--Pb, Converter retrofit & HSA Lime Injection/
Baghouses. SO2. Baghouse.
Asarco--Hayden Smelter........ Storage & SIP Action--Pb... Limits on Lead Bearing Fugitive Dust from
Handling. the Hayden smelter.
Asarco--Hayden Smelter........ Unpaved Road SIP Action--Pb... Limits on Lead Bearing Fugitive Dust from
Traffic. the Hayden smelter.
Asarco--Hayden Smelter........ Flash Furnace/ SIP Action--SO2.. Flash furnace fugitive SO2 capture and
Converter control improvements made as part of the
Primary converter retrofit project.
Ventilation--Aci
d Plant Outlet.
Asarco--Hayden Smelter........ Converter Aisle SIP Action--SO2.. New tertiary ventilation system.
Fugitives.
Asarco--Hayden Smelter........ Fines Crushing SIP Action--Pb... Limits on Lead Bearing Fugitive Dust from
Circuit. the Hayden smelter.
Asarco--Hayden Smelter........ Flash Furnace SIP Action--SO2.. Flash furnace fugitive SO2 capture and
Fugitives. control improvements made as part of the
converter retrofit project.
Asarco--Hayden Smelter........ Flash Furnace SIP Action--SO2.. Flash furnace fugitive SO2 capture and
Baghouse Outlet. control improvements made as part of the
converter retrofit project.
Asarco--Hayden Smelter........ Peirce Smith SIP Action--SO2.. New tertiary ventilation system.
Converters.
Asarco--Hayden Smelter........ Peirce Smith SIP Action--Pb, Converter retrofit & HSA Lime Injection/
Converters. SO2. Baghouse.
Asarco--Hayden Smelter........ Revert Crushing SIP Action--Pb... Limits on Lead Bearing Fugitive Dust from
Circuit. the Hayden smelter.
Asarco--Hayden Smelter........ Secondary Hood SIP Action--SO2.. New tertiary ventilation system.
Baghouse.
[[Page 47414]]
Asarco--Hayden Smelter........ Tertiary Hood SIP Action--SO2.. New tertiary ventilation system.
Ventilation
Outlet.
Calportland-Rillito Cement Preheater & Kiln Regional Haze-- SNCR installation with a NOX limit of 3.46
Plant. 4. Reasonable lb/ton.
Progress.
Chemical Lime Nelson Plant.... Baghouse......... Regional Haze-- SNCR NOX limit of 3.80 lb/ton. Use of
BART. lower sulfur fuel with SO2 limit of 9.32
lb/ton.
Chemical Lime Nelson Plant.... Baghouse......... Regional Haze-- SNCR NOX limit of 2.61 lb/ton. Use of
BART. lower sulfur fuel with SO2 limit of 9.73
lb/ton.
Coronado Generating Plant..... Coal Combustion Regional Haze-- Selective catalytic reduction (SCR)
Unit 1. BART. installation or shut down by 12/31/2025.
0.065 lb/MMBtu average NOX limit and
0.060 lb/MMBtu average SO2 limit.
Additional facility-wide cap on SO2
emissions.
Coronado Generating Plant..... Fuel Oil Regional Haze-- SCR installation or shut down by 12/31/
Combustion Unit BART. 2025. 0.065 lb/MMBtu average NOX limit
1. and 0.060 lb/MMBtu average SO2 limit.
Additional facility-wide cap on SO2
emissions.
Coronado Generating Plant..... Coal Combustion Regional Haze-- SCR installation in June 2014.
Unit 2. BART.
Coronado Generating Plant..... Fuel Oil Regional Haze-- SCR installation in June 2014.
Combustion Unit BART.
2.
Freeport McMoran Miami Smelter Smelting: Isa & SIP Action--SO2.. 2018 environmental upgrades included
Elf. capture of anode vessel process
emissions, routing to baghouse and
caustic scrubber.
Freeport McMoran Miami Smelter Captured SIP Action--SO2.. Anode process emissions routed through
Converter baghouse and caustic scrubber, Converter
Fugitives and fugitive emissions routed through caustic
Anode Process scrubber.
Emissions.
Freeport McMoran Miami Smelter Collected SIP Action--SO2.. Vent fume system, including Wet
Fugitives. Electrostatic Precipitator (ESP) and
caustic scrubber.
Freeport McMoran Miami Smelter Bypass Stack..... SIP Action--SO2.. Bypass stack subject to facility-wide SO2
limit in SO2 and permit.
Freeport McMoran Miami Smelter Smelting SIP Action--SO2.. Fugitive originating from IsaSmelt vessel,
Fugitives. electric furnace, converters, and anode
vessels, each of which have emissions
capture and control systems.
Freeport McMoran Miami Smelter Natural Gas SIP Action--SO2.. Majority of smelter natural gas combustion
Combustion. occurs within IsaSmelt, Electric Furnace,
Converters and Anode Vessels and is co-
mingled with process gas which is routed
to the various control devices.
Insignificant emissions originating from
uncontrolled space heaters, small water
heaters, etc.
Freeport McMoran Miami Smelter Anode Refining... SIP Action--SO2.. 2018 environmental upgrades included
capture of anode vessel process
emissions, routing to baghouse and
caustic scrubber.
Phoenix Cement--Clarkdale..... Raw Mill/Kiln.... Regional Haze-- SNCR installation with a NOX limit of 2.67
Reasonable lb/ton.
Progress.
Phoenix Cement--Clarkdale..... Coal Milling..... Regional Haze-- SNCR installation with a NOX limit of 2.67
Reasonable lb/ton.
Progress.
Tucson Electric Power-- U1 Boiler-- PSD BACT......... Replacement of unit with 10 upgraded
Irvington. Natural Gas. reciprocating internal combustion engines
(RICE) engines and a combined annual NOX
limit of 170 tons per year (tpy).
Tucson Electric Power-- U2 Boiler-- PSD BACT......... Replacement of unit with 10 upgraded RICE
Irvington. Natural Gas. engines and a combined annual NOX limit
of 170 tpy.
Tucson Electric Power-- U4 Boiler-- Regional Haze-- Fuel switch with a 0.25 lb/MMBtu NOX
Irvington. Natural Gas. BART Alternative. limit, 0.57 lb/MMBtu SO2 limit, and 0.010
lb/MMBtu PM10 limit.
Tucson Electric Power-- IGT1-Turbine--Nat PSD BACT......... Replacement of unit with 10 upgraded RICE
Irvington. ural Gas. engines and a combined annual NOX limit
of 170 tpy.
Tucson Electric Power-- IGT2-Turbine--Nat PSD BACT......... Replacement of unit with 10 upgraded RICE
Irvington. ural Gas. engines and a combined annual NOX limit
of 170 tpy.
----------------------------------------------------------------------------------------------------------------
Source: 2022 Arizona Regional Haze Plan, Appendix C, Exhibit CI.
ADEQ then recalculated Q/d using a threshold of 10 for each
facility utilizing the remaining processes and 2018 data.
Based on the source screening results, ADEQ determined that the 11
permitted sources listed in Table 4 of this document would undergo a
four-factor analysis.\158\
---------------------------------------------------------------------------
\158\ 2022 Arizona Regional Haze Plan, Table 8-2.
Table 4--Arizona Source Screening Results
----------------------------------------------------------------------------------------------------------------
Facility Q (tpy) d (km) Q/d Nearest Class I area
----------------------------------------------------------------------------------------------------------------
ASARCO LLC--Mission Complex............... 1,254 42 30 Saguaro National Park.
ASARCO LLC--Ray Operations................ 371 26 14 Superstition Wilderness Area.
[[Page 47415]]
CalPortland--Rillito Cement Plant......... 246 8 30 Saguaro National Park.
Drake Cement LLC.......................... 375 22 17 Sycamore Canyon Wilderness
Area.
El Paso Natural Gas--Willcox Compressor 321 27 12 Chiricahua Wilderness Area.
Station.
El Paso Natural Gas--Williams Compressor 786 19 40 Sycamore Canyon Wilderness
Station. Area.
Freeport-McMoran--Morenci................. 2,768 54 52 Gila Wilderness Area.
Freeport-McMoran--Sierrita Mine........... 869 42 21 Saguaro National Park.
Phoenix Cement--Clarkdale................. 136 10 14 Sycamore Canyon Wilderness
Area.
Tucson Electric Power Co--Irvington....... 444 16 28 Saguaro National Park.
Tucson Electric Power Co--Springerville... 17,044 50 339 Mount Baldy Wilderness Area.
----------------------------------------------------------------------------------------------------------------
Source: 2022 Arizona Regional Haze Plan, Table 8-2. The Q and Q/d values shown here exclude those processes that
ADEQ screened out based on a finding that they were effectively controlled.
ii. Overall Approach to Four-Factor Analyses
For cost calculation interest rates, ADEQ requested that the
sources undergoing a four-factor analysis provide source specific
lending/interest rates in line with the general recommendations of the
7th Edition of the EPA Control Cost Manual.\159\ In the absence of
source-specific information, ADEQ relied on a 4.75 percent interest
rate developed by analyzing and averaging historical bank prime rate
data. ADEQ looked at 3-year average bank prime rates for the periods of
2017-2019 (4.83 percent) and April 2018-March 2020 (4.78 percent).
These dates were chosen as they were the most recent data at the time
of the analysis. ADEQ determined, based on these 3-year averages, that
a 3-year average bank prime rate of 4.75 percent was appropriate. ADEQ
indicates that the use of a 3-year average was more appropriate than
the utilization of the bank prime rate at a singular point in time due
to the variability that can occur in bank prime rates over time. ADEQ
also performed an analysis to determine a reasonable cost-effectiveness
(cost/ton) threshold for Arizona emissions sources evaluated under the
four-factor analysis in the regional haze second planning period, based
on the cost-effectiveness values for controls required in regional haze
SIP revisions from the first planning period. ADEQ indicated that it
found that none of the implemented cost-effectiveness values during the
first planning period exceeded $5,300/ton. Adjusting the cost for
inflation to 2019 dollars based on Chemical Engineering Plant Cost
Index values,\160\ ADEQ determined that any controls having an average
cost-effectiveness of more than $6,500/ton would be cost excessive and
could be rejected without further justification.
---------------------------------------------------------------------------
\159\ 2022 Arizona Regional Haze Plan, Section 8.3.2.
\160\ Available at <a href="https://www.chemengonline.com/site/plant-cost-index/">https://www.chemengonline.com/site/plant-cost-index/</a>.
---------------------------------------------------------------------------
iii. Summary of Four-Factor Analyses
Table 5--Summary of Facilities and Processes Evaluated Under Four-Factor Analysis
----------------------------------------------------------------------------------------------------------------
Projected 2028
Facility Process Pollutant emissions (tpy)
----------------------------------------------------------------------------------------------------------------
ASARCO LLC--Mission Complex............ Trucks hauling ore and PM10..................... 713
waste rock.
Rubber tire rigs traveling PM10..................... 97
on unpaved roads.
ASARCO LLC--Ray Operations............. Trucks hauling ore and PM10..................... 158
waste rock.
Miscellaneous vehicles PM10..................... 87
traveling on unpaved
roads.
Dumps and tailings PM10..................... 41
windblown dust.
Dozing mine areas, dumps PM10..................... 21
and stockpiles.
Blasting ore and waste NOX...................... 89
rock.
CalPortland--Rillito Cement Plant...... Clinker From K234-- PM10..................... 62.5
Overhead Crane Building.
Unpaved Roads............. PM10..................... 51.7
Plant Materials........... PM10..................... 17.3
Finish Milling--D2-PC..... PM10..................... 9.5
Iron Stockpile............ PM10..................... 8.5
Finish Milling--D3-1-DC2.. PM10..................... 7.1
Cooler--Kiln 4 H2-GB...... PM10..................... 7.0
Quarry Materials.......... PM10..................... 6.5
Paved Roads............... PM10..................... 5.8
Mining Operations-- NOX...................... 5.7
Blasting.
Quarry Crusher System--B2- PM10..................... 5.3
DC1.
Drake Cement LLC....................... Raw Mill and Kiln......... NOX...................... \a\ 316
El Paso Natural Gas--Willcox Compressor TURBINE-1................. NOX...................... 134
Station.
TURBINE-2................. NOX...................... 157
El Paso Natural Gas--Williams TURBINE-1................. NOX...................... 290
Compressor Station.
RECIP-1................... NOX...................... 148
RECIP-2................... NOX...................... 170
RECIP-5................... NOX...................... 205
Freeport--McMoran--Morenci............. Haul Trucks Traveling on PM10..................... 1,552
Mine Roads.
Other Vehicles Traveling PM10..................... 229
on Mine Roads.
Loading Ores into Haul PM10..................... 120
Trucks.
[[Page 47416]]
Freeport--McMoran--Sierrita Mine....... Unpaved Roads............. PM10..................... 449
Loading Ores into Haul PM10..................... 82
Trucks.
Sierrita Tailings......... PM10..................... 171
Blasting Operations....... NOX...................... 97
Phoenix Cement--Clarkdale.............. Rock Sampling and Storage-- PM10..................... 31.4
Raw Storage Piles.
Coal/Coke Handling 2--Coal/ PM10..................... 12.1
Coke Storage Pile.
Gypsum Handling--Gypsum PM10..................... 7.4
Storage Piles.
Cement Storage--DC510..... PM10..................... 5.5
Quarry Rds/Blast/Drill-- NOX...................... 3.5
Quarry--Blasting.
Raw Storage and Homog2-- PM10..................... 3.1
DC607.
Kiln Feed System--DC409... PM10..................... 3.0
Clinker Handling and STR3-- PM10..................... 2.8
DC352.
Finish Milling--DC340..... PM10..................... 2.6
Cement Storage 2--DC512... PM10..................... 2.6
Raw Mill--DC366........... PM10..................... 2.2
Rock Reclaimer and TPS-- PM10..................... 2.4
DC205.
Cement Storage 2--DC508... PM10..................... 2.1
Clinker Handling and STR3-- PM10..................... 2.0
DC350.
Raw Storage and Homog1-- PM10..................... 1.9
DC601.
Clinker Handling and STR1-- PM10..................... 1.9
DC447.
Clinker Cooling--DC445.... PM10..................... 1.7
Clinker Handling and STR3-- PM10..................... 1.6
DC312.
Raw Storage and Homog2-- PM10..................... 1.6
DC224.
Raw Storage and Homog2-- PM10..................... 1.6
DC228.
Raw Storage and Homog2-- PM10..................... 1.6
DC615.
Raw Storage and Homog2-- PM10..................... 1.6
DC616.
Coal/Coke Handling1--DC452 PM10..................... 1.4
Finish Milling--DC341..... PM10..................... 1.3
Paved Plant Roads......... PM10..................... 1.2
Tucson Electric Power Co--Irvington.... Unit 3.................... NOX...................... 251
Tucson Electric Power Co--Springerville Unit 1 Boiler............. PM10..................... 92
NOX...................... 2,099
SO2...................... 2,869
Unit 2 Boiler............. PM10..................... 107
NOX...................... 2,283
SO2...................... 2,982
Unit 3 Boiler............. PM10..................... 158
NOX...................... 1,019
SO2...................... 1,036
Unit 4 Boiler............. PM10..................... 31
NOX...................... 929
SO2...................... 1,039
----------------------------------------------------------------------------------------------------------------
\a\ The Plan does not state the projected 2028 emissions for this unit. However, the highest annual facility-
wide NOX emissions during the baseline period were 316 tpy in 2018, so this may be considered an upper-bound
of emissions from the Raw Mill and Kiln.
Source: 2022 Arizona Regional Haze Plan, Appendix C.
ASARCO LLC (Asarco) Mission Complex \161\ is a copper mine located
in Sahuarita, Arizona. The facility operates an open-pit copper mine,
two concentrators, and a by-products molybdenum plant. Asarco Mission
Complex was screened in with a Q/d value of 30, and the nearest Class I
area is Saguaro National Park at 42 kilometers away. ADEQ identified
two processes that are subject to the four-factor analysis for Asarco
Mission Complex: haul trucks hauling ore and waste rock, and rubber
rigs traveling on unpaved roads. Using information supplied by Asarco,
ADEQ conducted four-factor analyses for these two processes, the
results of which are summarized in Table 6 of this document. Based on
these results, ADEQ determined that the emissions controls that Asarco
is implementing for the two processes, such as a speed limit of 35
miles per hour and application of water, reflect current best
management practices for the mining industry and that it is reasonable
not to require additional controls during this planning period.
Although ADEQ did not specify why no other controls were reasonable,
cost appears to have been the determining factor, as the cost
effectiveness of all feasible controls exceeded ADEQ's chosen cost-
effectiveness threshold of $6,500/ton.
---------------------------------------------------------------------------
\161\ 2022 Arizona Regional Haze Plan, Chapter 8.3.3.1 and
Appendix C, Section C3.3.
[[Page 47417]]
Table 6--Summary of Control Options for Asarco Mission Complex
----------------------------------------------------------------------------------------------------------------
Cost-
Process Control Emission reduction effectiveness
($/ton)
----------------------------------------------------------------------------------------------------------------
Truck Hauling Ore and Waste Rock........ Reduce the speed limit for 203.7..................... $80,544
haul trucks from 35 mph
to 25 mph.
Apply additional water to 71.3...................... 12,183
haul roads (outside pit
only).
Apply additional water to 356.5..................... 10,117
haul roads (inside and
outside pit).
Increase freeboard in the Emissions reductions could N/A
haul trucks. not be quantified.
Rubber Tire Rigs Traveling on Unpaved Reduce the speed limit for No reduction expected N/A
Non-Haul Roads. rubber tire rigs from 35 since average traveling
mph to 25 mph. speed of rubber tire rigs
is 15 mph.
Apply additional water to 49.7...................... 18,043
unpaved roads (non-haul
roads only).
Apply additional water to 59.4...................... 15,771
unpaved roads (haul roads
non-haul roads only).
Apply and maintain surface 5.1....................... 25,711
gravel on unpaved non-
haul roads (decreasing
the silt content from
6.9% to 6.4%).
Paving unpaved non-haul 73.7...................... 47,295
roads.
----------------------------------------------------------------------------------------------------------------
Source: 2022 Arizona Regional Haze Plan, Appendix C, Section C.3.3.
Asarco Ray Operations is located near Kearny, Arizona and consists
of an open pit mine, concentrator, solvent extraction-electrowinning
operation, and associated maintenance, warehouse, and administrative
facilities.\162\ The facility was screened in with a Q/d value of 14,
and the nearest Class I area is Saguaro National Park at 26 kilometers
away. ADEQ identified five processes that are subject to the four-
factor analysis for Asarco Ray Operations: trucks hauling ore and waste
rock, miscellaneous vehicles traveling on unpaved roads, dumps and
tailings windblown dust, dozing mine areas, dumps and stockpiles, and
blasting ore and waste rock. Asarco completed and submitted a four-
factor analysis report for the five processes in December 2019 and
provided additional information in March 2020 through 2021. ADEQ's
determination in the 2022 Arizona Regional Haze Plan is that the
emissions controls that Asarco is implementing for these processes,
such as a speed limit of 35 miles per hour, water sprays, and
application of chemical dust suppressants (on non-haul roads), reflect
current best management practices for the mining industry and that it
is reasonable not to require additional controls during this planning
period.
---------------------------------------------------------------------------
\162\ 2022 Arizona Regional Haze Plan, Chapter 8.3.3.2 and
Appendix C, Section C3.4.
---------------------------------------------------------------------------
CalPortland Rillito Cement Plant is a portland cement manufacturing
plant in Rillito, Arizona.\163\ The facility was screened in with a Q/d
value of 30, and the nearest Class I area is Superstition Wilderness
Area at 8 kilometers away. ADEQ evaluated potential controls at nine
emissions sources at the CalPortland Rillito Cement Plant and conducted
a four-factor analysis for each control that it found to be feasible.
The results of these analyses are shown in Table 7. While ADEQ's was
conducting its four-factor analysis for the Rillito facility,
CalPortland took on a voluntary, enforceable air quality control permit
condition for the location of its iron stockpile (horseshoe pit, three-
sided artificial windbreak).\164\ ADEQ subsequently found that no other
controls were reasonable based the statutory four factors. Although
ADEQ did not specify why no other controls were reasonable, cost
appears to have been the determining factor, as the cost effectiveness
of all feasible controls exceeded ADEQ's chosen cost-effectiveness
threshold of $6,500/ton.
---------------------------------------------------------------------------
\163\ 2022 Arizona Regional Haze Plan, Chapter 8.3.3.3 and
Appendix C.
\164\ ADEQ Air Quality Control Permit #85424 Attachment C
Section XI Regional Haze Requirements of the 2022 Arizona Regional
Haze Plan. ADEQ has not submit the new permit condition as a SIP
revision.
Table 7--Summary of Control Options for CalPortland Cement
----------------------------------------------------------------------------------------------------------------
Technically Emissions Cost-
Source Control option feasible (Y/ reduction effectiveness ($/
N) (tpy) ton)
----------------------------------------------------------------------------------------------------------------
Clinker to Overhead Crane Building.... Fabric Filter Baghouse.. N N/A N/A
Clinker to Overhead Crane Building.... Full Enclosure.......... Y 9.38 $13,605
Unpaved Road Vehicular Traffic........ Traffic Management Plans N N/A N/A
Unpaved Road Vehicular Traffic........ Additional Watering..... Y 44.34 23,955
Unpaved Road Vehicular Traffic........ Surface Gravel.......... N N/A N/A
Unpaved Road Vehicular Traffic........ Paving.................. N N/A N/A
Unpaved Road Vehicular Traffic........ Chemical Dust N N/A N/A
Suppressant.
Paved Road Vehicular Traffic.......... Cover Haul Trucks....... N N/A N/A
Paved Road Vehicular Traffic.......... Stabilize Unpaved Points Y 0 N/A
Paved Road Vehicular Traffic.......... Rapid Cleanup of Spills. N N/A N/A
Paved Road Vehicular Traffic.......... Curb or Pave Shoulders.. N N/A N/A
Paved Road Vehicular Traffic.......... Street Sweepers......... Y 1.5 28,146
[[Page 47418]]
Material Handling..................... Water Sprays............ N N/A N/A
Material Handling..................... Baghouse................ N N/A N/A
Material Handling..................... Enclosures.............. N N/A N/A
Iron Stockpile........................ Water Application....... N N/A N/A
Iron Stockpile........................ Chemical Dust N N/A N/A
Suppressant.
Iron Stockpile........................ Artificial Wind Break... Y 0 N/A
Iron Stockpile........................ Vegetative Wind Break... Y 0 N/A
Iron Stockpile........................ Compact Piles........... N N/A N/A
Iron Stockpile........................ Cover with Tarps........ N N/A N/A
Finish Mill........................... Improved Baghouses...... Y 15.85-18.26 14,254-16,057
Clinker Cooler........................ Improved Baghouses...... Y 21.19 16,210
Quarry Crusher........................ Improved Baghouses...... Y 5.92 12,099
Blasting.............................. N/A..................... N/A N/A N/A
----------------------------------------------------------------------------------------------------------------
Source: 2022 Arizona Regional Haze Plan Appendix C, Section C.3.5.
The Drake Cement Paulden facility is a Portland cement
manufacturing facility in Paulden, Yavapai County, Arizona.\165\ The
facility was screened in with a Q/d value of 17, and the nearest Class
I area is Sycamore Canyon Wilderness Area at 22 kilometers away. One
emission source, the Main Baghouse Raw Mill and Kiln, contributed
approximately 84 percent of the facility's total NO<INF>X</INF>,
SO<INF>2</INF>, and PM<INF>10</INF> combined emissions, and ADEQ
evaluated this unit for regional haze controls. The Plan does not state
the projected 2028 emissions for this unit. However, the highest annual
facility-wide NO<INF>X</INF> emissions during the baseline period were
316 tpy in 2018, so this may be considered an upper-bound of emissions
from the Raw Mill and Kiln. ADEQ indicated that Low NO<INF>X</INF>
Burners, Preheater Riser Duct Firing, and SNCR are currently
implemented at the Drake Cement Paulden facility. The only remaining
potential control available for implementation at the Paulden facility
is SCR. Noting that SCR has been employed at only a handful of cement
plants in Europe and one in the United States, ADEQ concluded that SCR
was technically infeasible. Despite this, ADEQ conducted a four-factor
analysis of SCR, using a control efficiency of 65 percent, which
resulted in a reduction of 83.6 tons per year at approximately $30,521/
ton.\166\ This cost exceeds ADEQ's cost threshold and therefore, ADEQ
determined that it is reasonable not to require additional controls on
Drake Cement during this planning period.
---------------------------------------------------------------------------
\165\ 2022 Arizona Regional Haze Plan, Appendix C, Section C3.6.
\166\ Drake Cement estimated a cost effectiveness of $28,641/ton
utilizing a 3 percent interest rate. ADEQ updated the interest rate
to 4.75 percent for consistency with other four-factor analyses in
its SIP submittal. The cost is based on a 30-year lifespan of the
SCR.
---------------------------------------------------------------------------
EPNG Willcox Compressor Station is a natural gas compressor station
facility that provides natural gas compression to EPNG's pipeline
network.\167\ The facility screened in with a Q/d value of 12, and the
nearest Class I area is Chiricahua Wilderness Area at 27 kilometers
away. The two units subject to four-factor analysis were TURBINE-1 and
TURBINE-2, with 2028 emissions of 134.72 and 157.44 tons
NO<INF>X</INF>, respectively.
---------------------------------------------------------------------------
\167\ 2022 Arizona Regional Haze Plan, Chapter 8.3.3.6 and
Appendix C, Section C3.8.
---------------------------------------------------------------------------
ADEQ found that EPNG was already implementing Good Combustion
Practices at both units, and that the following control options would
be technically feasible: Combustion Liner Upgrade with Dry Low
NO<INF>X</INF> (DLN; 68-71 percent control effectiveness) and SCR (77
percent control effectiveness). The results of ADEQ's analysis of these
two options are summarized in Table 8 of this document.
Table 8--Summary of Control Options for EPNG Willcox
----------------------------------------------------------------------------------------------------------------
Cost-
Process Control Emission effectiveness
reduction ($/ton)
----------------------------------------------------------------------------------------------------------------
TURBINE-1.................................. Lean Head End Combustion Liner 91.24 $12,764
Upgrade with Dry Low-NOX Control.
SCR................................ 106 10,008
TURBINE-2.................................. Lean Head End Combustion Liner 115.82 10,524
Upgrade with Dry Low-NOX Control.
SCR................................ 124 8,892
----------------------------------------------------------------------------------------------------------------
Source: 2022 Arizona Regional Haze Plan, Appendix C, Section C3.8.
ADEQ determined that neither the Combustion Liner Upgrade with DLN
nor SCR are cost-effective options because they exceed ADEQ's cost
threshold. ADEQ found that EPNG should continue to implement Good
Combustion Practices but did not consider whether or not this measure
was necessary to make reasonable progress.
El Paso Natural Gas (EPNG) Williams Compressor Station is a natural
gas compressor station facility that provides natural gas compression
to EPNG's pipeline network.\168\ The facility was screened in with a Q/
d value of 40, and the nearest Class I area is Sycamore Canyon
Wilderness Area at 19 kilometers away. EPNG reviewed NO<INF>X</INF>
control options for both the General Electric (GE) gas turbine
(TURBINE-1, with 2028 emissions of 290.42 tons NO<INF>X</INF>) and
three reciprocating engines (RECIP-1, RECIP-2, and RECIP-5, with
[[Page 47419]]
2028 emissions of 148.4, 179.4, and 205.16 tons NO<INF>X</INF>,
respectively) located at the Williams Compressor Station.
---------------------------------------------------------------------------
\168\ 2022 Arizona Regional Haze Plan, Chapter 8.3.3.5 and
Appendix C, Section C3.7.
---------------------------------------------------------------------------
Based on information provided by EPNG, ADEQ evaluated the following
controls for the Williams compressor station TURBINE-1 for
NO<INF>X</INF>: Water or Steam Injection, Combustion Liner Upgrade with
Low NO<INF>X</INF> Burner Design, Good Combustion Practices,
EMX<SUP>TM</SUP>/SCONOX<SUP>TM</SUP> Technology, SCR, and SNCR. Of the
list, ADEQ determined three of the control options to be technically
feasible: water or steam injection (74 percent control effectiveness),
SCR (80 percent control effectiveness), and combustion liner upgrade
with low NO<INF>X</INF> burner design (78 percent control
effectiveness). The results of this analysis are summarized in Table 9
of this document. After the evaluation of these costs of compliance,
ADEQ determined that the control options were not cost effective, and
that the continued use of Good Combustion Practices is reasonable for
TURBINE-1. ADEQ did not determine whether this measure was necessary to
make reasonable progress.
Additionally, the following controls were evaluated for the three
Williams compressor station reciprocating engines: SCR, Air-Fuel Ratio
Adjustment with High Energy Ignition, Low-Emission Combustion (LEC)
Retrofits, Replacement of Three Engines with one Low NO<INF>X</INF>
Emissions Gas Turbine, Replacement of Three Engines with Electric
Motors or a Gas Turbine, and Good Combustion Practices. The results of
ADEQ's four-factor analysis for the engines are summarized in Table 9
of this document. Based on these results, ADEQ found that all LEC
options were cost-effective for every engine based on average cost-
effectiveness. However, ADEQ also found that the incremental cost
effectiveness of requiring LEC-3 on RECIP-1 as compared to requiring
LEC-2 ($11,120/ton) was ``cost-excessive.'' Therefore, while ADEQ
determined that LEC-3 was necessary to make reasonable progress for
RECIP-2 and RECIP-5, it selected a less stringent control, LEC-2, for
RECIP-1. ADEQ also found that replacement of the three engines with a
gas turbine would be cost-effective but did not adopt this option due
to issues and uncertainties with this option, such as the need for
operational flexibility to control pipeline flowrate changes and a
potential increase in fuel usage and emissions during low flow
conditions.\169\
---------------------------------------------------------------------------
\169\ Id. at 126-127.
Table 9--Summary of Control Options for EPNG Williams
----------------------------------------------------------------------------------------------------------------
Cost-
Process Control Emission effectiveness
reduction ($/ton)
----------------------------------------------------------------------------------------------------------------
TURBINE-1.................................. Water Injection.................... 201.54 $6,536
Steam Injection.................... 201.54 7,601
Combustion Liner Upgrade and Low 213.5 8,775
NOX Burner Design.
SCR................................ 219 8,051
RECIP-1.................................... Air-Fuel Ratio Adjustment with High 20.67 2,484
Energy Ignition.
LEC-1.............................. 76.46 4,058
LEC-2.............................. 116.30 4,581
LEC-3.............................. 131.45 5,334
SCR................................ 119.18 5,782
Replacement with Electric Motors... 140.21 20,880
RECIP-2.................................... LEC-1.............................. 74.36 4,172
LEC-2.............................. 127.42 4,181
LEC-3.............................. 147.59 4,751
SCR................................ 135.37 5,553
Replacement with Electric Motors... 159.26 23,301
RECIP-5.................................... LEC-1.............................. 87.51 3,645
LEC-2.............................. 181.86 2,977
LEC-3.............................. 217.72 3,302
SCR................................ 202.70 4,409
Replacement with Electric Motors... 238.47 27,011
RECIP-1, 2, & 5............................ Replacement of Three Engines with 484.21 3,905
Low NOX Emissions Gas Turbine.
----------------------------------------------------------------------------------------------------------------
Source: 2022 Arizona Regional Haze Plan, Appendix C, Section C.3.7.
Freeport-McMoRan Morenci Complex is located in Greenlee County,
Arizona and consists of three major operations: mining operations,
including the drilling and blasting of ore in open-pit copper mines,
three in-pit crushers and an ore conveying system, the Morenci
Concentrator and Metcalf Concentrator operations for production of
copper and molybdenum concentrates through conventional milling and
froth flotation operations, and the Metcalf Mine-for-Leach (MFL) plant
and five Solution Extraction and four Electrowinning facilities (SX/EW)
operations for production of high quality copper cathodes through
leaching and hydrometallurgy.\170\ The facility was screened in with a
Q/d value of 52 and the nearest Class I area is Gila Wilderness Area at
54 kilometers away.
---------------------------------------------------------------------------
\170\ 2022 Arizona Regional Haze Plan, Chapter 8.3.3.7 and
Appendix C, Section C3.9.
---------------------------------------------------------------------------
ADEQ identified two processes that are subject to the four-factor
analysis for Freeport-McMoRan Morenci: haul trucks and other vehicles
travel on mine roads and loading ore into haul trucks. Using
information supplied by Freeport-McMoRan, ADEQ conducted four-factor
analyses for these two processes, the results of which are summarized
in Table 10 of this document. Based on these results, ADEQ determined
that the emissions controls Freeport is already implementing for the
two processes, such as a speed limit of 35 miles per hour and
application of water, reflect current best management practices for the
mining industry, and that it is reasonable not to require additional
controls during this planning period. Although ADEQ did not specify why
it found that no other controls were reasonable, cost appears to have
been the determining factor, as the cost effectiveness of all feasible
controls
[[Page 47420]]
exceeded ADEQ's chosen threshold of $6,500/ton.
Table 10--Summary of Control Options for Freeport-McMoRan Morenci
----------------------------------------------------------------------------------------------------------------
Cost-
Process Control Emission reduction effectiveness
($/ton)
----------------------------------------------------------------------------------------------------------------
Haul Trucks and Other Vehicles Reduce the speed limit 427............................. $383,018
Traveling on Mine Roads. for haul trucks to 25
mph.
Apply additional water 890.8........................... 10,949
to unpaved mine roads.
Increase freeboard in Not quantifiable................ N/A
the haul trucks.
Loading Ores into Haul Trucks........ Apply additional water 52.06........................... 406,990
to ores.
Ceasing operations 0.06............................ 14,625,548
during high wind hours.
----------------------------------------------------------------------------------------------------------------
Source: 2022 Arizona Regional Haze Plan, Appendix C, Section C.3.9.
Freeport-McMoRan Sierrita Complex is located in southern Pima
County, Arizona and consists of three major operations: mining
operations, including the drilling and blasting of ore in open-pit
copper mines, the Sierrita concentrator operations for production of
copper and molybdenum concentrates, and the run of mine (ROM) oxide-
leaching plant and the Twin Buttes SX/EW operations for production of
high quality copper cathodes.\171\ The facility was screened in with a
Q/d value of 21, and the nearest Class I area is Saguaro National Park
at 42 kilometers away. ADEQ identified four processes that are subject
to the four-factor analysis for the Freeport-McMoRan Sierrita complex:
vehicle travel on unpaved roads, tailings, loading/unloading ore into
haul trucks, and blasting operations. Using information supplied by
Freeport-McMoRan, ADEQ conducted four-factor analyses for these four
processes, the results of which are summarized in Table 11 of this
document. Based on these results, ADEQ determined that the emissions
controls Freeport-McMoRan is already implementing, such as a speed
limit of 35 miles per hour and water application, reflect current best
management practices for the mining industry, and that it is reasonable
not to require additional controls during this planning period.
Although ADEQ did not specify why it found that no other controls were
reasonable, cost appears to have been the determining factor, as the
cost effectiveness of all feasible controls exceeded ADEQ's chosen
threshold of $6,500/ton.
---------------------------------------------------------------------------
\171\ 2022 Arizona Regional Haze Plan, Chapter 8.3.3.8 and
Appendix C, Section C3.10.
Table 11--Summary of Control Options for Freeport-McMoRan Sierrita
----------------------------------------------------------------------------------------------------------------
Cost-
Process Control Emission reduction effectiveness
($/ton)
----------------------------------------------------------------------------------------------------------------
Vehicle Travel on Unpaved Mine Roads. Reduce the speed limit 124............................. $233,539
from 34.5 mph to 25
mph.
Apply additional water 224.7........................... 12,021
to unpaved roads
(increasing the
control efficiency
from 90% to 95%).
Increase freeboard in Emissions reductions could not N/A
the haul trucks. be quantified.
Loading Ores into Haul Trucks........ Apply water to ores to 57.73........................... 240,703
increase the moisture
content from 2% to
4.8%.
Ceasing loading 0.66............................ 8,081,366
operations during high
wind hours.
Emissions from Tailings.............. No feasible controls... N/A............................. N/A
Blasting Operations.................. No feasible controls... N/A............................. N/A
----------------------------------------------------------------------------------------------------------------
Source: 2022 Arizona Regional Haze Plan, Appendix C, Section C.3.10.
Phoenix Cement Clarkdale Facility is a Portland cement plant and
quarry near Clarkdale, Arizona that is owned by an enterprise division
of the Salt River Pima-Maricopa Indian Community.\172\ The facility was
screened in with a Q/d value of 14, and the nearest Class I area is
Sycamore Canyon Wilderness Area at 10 kilometers away. As shown in
Table 3 of this document, ADEQ screened out the raw mill/kiln and coal
milling emissions sources because they were required to install SNCR as
part of the first implementation period of the Regional Haze Rule and
were deemed effectively controlled. The remaining emissions sources
subject to a four-factor analysis included: raw storage piles, coal/
coke storage piles, gypsum storage piles, paved plant roads, quarry
blasting, and material handling processes. Based on the results of
these analyses, which are summarized in Table 12 of this document, ADEQ
determined that no new controls were reasonable. Although ADEQ did not
specify its reasoning, cost appears to have been the determining
factor, as the cost effectiveness of all feasible controls exceeded
ADEQ's cost-effectiveness threshold of $6,500/ton.
---------------------------------------------------------------------------
\172\ 2022 Arizona Regional Haze Plan, Chapter 8.3.3.9 and
Appendix C, Section C3.11.
[[Page 47421]]
Table 12--Summary of Control Options for Phoenix Cement Clarkdale
----------------------------------------------------------------------------------------------------------------
Cost-
Process Control Emission reduction effectiveness
($/ton)
----------------------------------------------------------------------------------------------------------------
Raw Storage Piles....................... Enclosure................. 28.31..................... $154,422
Increase Moisture Content. Technically Infeasible.... N/A
Cover with Tarps.......... Technically Infeasible.... N/A
Coal/Coke Storage Pile.................. Enclosure................. 10.94..................... 228,410
Increase Moisture Content. Technically Infeasible.... N/A
Gypsum Storage Piles.................... Enclosure................. 6.64...................... 44,441
Increase Moisture Content. Technically Infeasible.... N/A
Cover with Tarps.......... Technically Infeasible.... N/A
Paved Plant Roads....................... Berm Installation......... Already Implemented....... N/A
Curbing/Paving or Shoulder Already Implemented....... N/A
Stabilization.
Curbing with Gutters...... Already Implemented....... N/A
[…truncated; see source link]Indexed from Federal Register on May 31, 2024.
This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.