Proposed Rule2026-16083
Partial Approval and Partial Disapproval of Air Quality State Implementation Plans; Arizona; Prevention of Significant Deterioration Infrastructure Requirements for the 2012 Fine Particulate Matter National Ambient Air Quality Standard
Primary source
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Published
August 6, 2026
Effective
September 8, 2026
Issuing agencies
Environmental Protection Agency
Abstract
The Environmental Protection Agency (EPA) is proposing to partially approve and partially disapprove a revision to the Arizona State implementation plan (SIP) as meeting the requirements of the Clean Air Act (CAA) for the implementation, maintenance, and enforcement of the 2012 fine particulate matter (PM<INF>2.5</INF>) national ambient air quality standard (NAAQS or "standards"). The EPA is proposing to approve the portions of Arizona's submission addressing prevention of significant deterioration (PSD) requirements in the permitting jurisdictions of the Arizona Department of Environmental Quality (ADEQ), Maricopa County Air Quality Department (MCAQD), and Pinal County Air Quality Control District (PCAQCD). The EPA is proposing to disapprove the portions of the Arizona submission addressing PSD requirements in the Pima County Department of Environmental Quality (PDEQ) permitting jurisdiction.
Full Text
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<title>Federal Register, Volume 91 Issue 150 (Thursday, August 6, 2026)</title>
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[Federal Register Volume 91, Number 150 (Thursday, August 6, 2026)]
[Proposed Rules]
[Pages 50742-50746]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-16083]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[EPA-R09-OAR-2026-3797; FRL-13389-01-R9]
Partial Approval and Partial Disapproval of Air Quality State
Implementation Plans; Arizona; Prevention of Significant Deterioration
Infrastructure Requirements for the 2012 Fine Particulate Matter
National Ambient Air Quality Standard
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule; withdrawal.
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SUMMARY: The Environmental Protection Agency (EPA) is proposing to
partially approve and partially disapprove a revision to the Arizona
State implementation plan (SIP) as meeting the requirements of the
Clean Air Act (CAA) for the implementation, maintenance, and
enforcement of the 2012 fine particulate matter (PM<INF>2.5</INF>)
national ambient air quality standard (NAAQS or ``standards''). The EPA
is proposing to approve the portions of Arizona's submission addressing
prevention of significant deterioration (PSD) requirements in the
permitting jurisdictions of the Arizona Department of Environmental
Quality (ADEQ), Maricopa County Air Quality Department (MCAQD), and
Pinal County Air Quality Control District (PCAQCD). The EPA is
proposing to disapprove the portions of the Arizona submission
addressing PSD requirements in the Pima County Department of
Environmental Quality (PDEQ) permitting jurisdiction.
DATES: Comments must be received by September 8, 2026. As of July 21,
2026, the proposed rule published on June 13, 2024, at 89 FR 50245, is
withdrawn insofar as it related to the PSD-related requirements of CAA
sections 110(a)(2)(C), 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii), and
110(a)(2)(J).
ADDRESSES: The EPA has established a docket for this action under
Docket ID No. EPA-R09-OAR-2026-3797. All documents in the docket are
listed on the <a href="https://www.regulations.gov">https://www.regulations.gov</a> website. Although listed in
the index, some information is not publicly available, e.g.,
Confidential Business Information (CBI) or other information whose
disclosure is restricted by statute. Certain other material, such as
copyrighted material, is not placed on the internet and will be
publicly available only in hard copy form. Publicly available docket
materials are available through <a href="https://www.regulations.gov">https://www.regulations.gov</a>, or please
contact the person identified in the FOR FURTHER INFORMATION CONTACT
section for additional availability information. 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: Michael Dorantes, Geographic
Strategies and Modeling Section (AIR-2-2), EPA Region IX, 75 Hawthorne
Street, San Francisco, CA; telephone number: (415) 972-3934; email
address: <a href="/cdn-cgi/l/email-protection#1b7f74697a756f7e6835767278737a7e775b7e6b7a357c746d"><span class="__cf_email__" data-cfemail="6c08031e0d0218091f4201050f040d09002c091c0d420b031a">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION: Throughout this document, ``we,'' ``us,''
and ``our'' refer to the EPA.
Table of Contents
I. Statutory Requirements and the EPA's Considerations for
Evaluating Infrastructure SIPs
II. Background and Withdrawal of the EPA's Prior Proposed Partial
Approval and Partial Disapproval of PSD Requirements Under CAA
sections 110(a)(2)(C), 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii), and
110(a)(2)(J)
III. The EPA's Updated Policy Rationale and Summary of the EPA's
Proposed Partial Approval and Partial Disapproval
IV. Request for Public Comments
V. Statutory and Executive Order Reviews
I. Statutory Requirements and the EPA's Considerations for Evaluating
Infrastructure SIPs
The EPA has historically referred to SIP submittals made for the
purpose of satisfying the requirements of CAA sections 110(a)(1) and
110(a)(2) as ``infrastructure SIP'' (I-SIP) submittals. Although the
term ``infrastructure SIP'' does not appear in the CAA, the EPA uses
the term to distinguish this particular type of SIP submittal from
submittals that are primarily intended to satisfy other SIP
requirements under the CAA, such as ``nonattainment SIP'' or
``attainment SIP'' submittals intended to address the nonattainment
planning requirements of CAA title I part D, ``regional haze SIP''
submittals required by the EPA rule to address the visibility
protection requirements of CAA section 169A, and nonattainment new
source review (NSR) permit program submittals to address the permit
requirements of CAA title I part D.
CAA section 110(a)(1) addresses the timing and general requirements
for infrastructure SIP submittals, and CAA section 110(a)(2) provides
details concerning the required content of these submittals. Notably,
section 110(a)(1) of the Act clearly requires that each State adopt and
submit an infrastructure SIP
[[Page 50743]]
for the implementation, maintenance, and enforcement of each NAAQS
promulgated by the EPA, and that the EPA act on such SIP submittals,
while CAA section 110(a)(2) provides an extensive list of required
elements, some with provisions pertaining directly to legal authority,
some with provisions pertaining to substantive program requirements,
and some others which pertain to requirements for both authority and
substantive program provisions. The EPA has historically asserted that
this list of required provisions leads to ambiguities concerning what
is required for inclusion in any SIP submittal subject to CAA section
110(a)(2). For example, CAA section 110(a)(2) requires that ``each''
SIP submittal must meet the list of requirements therein. However, the
EPA has long noted that this literal reading of the statute is
internally inconsistent and would create a conflict with the
nonattainment provisions in CAA title I part D, which specifically
address nonattainment SIP requirements.\1\ Section 110(a)(2)(I) of the
CAA pertains to nonattainment SIP requirements, and part D addresses
when attainment plan SIP submittals to address nonattainment area
requirements are due. Moreover, CAA section 172(b) requires the EPA to
establish a schedule for submittal of such plans for certain pollutants
when the Administrator promulgates the designation of an area as
nonattainment, and CAA section 107(d)(1)(B) allows up to two years, or
in some cases three years, for such designations to be promulgated.\2\
As another example, CAA section 172(c)(7) requires that attainment plan
SIP submittals required by part D have to meet only the ``applicable
requirements'' of CAA section 110(a)(2). Thus, the EPA has interpreted
this provision such that attainment plan SIP submittals must meet the
requirements of CAA section 110(a)(2)(A) regarding enforceable
emissions limits and control measures and CAA section 110(a)(2)(E)(i)
regarding air agency resources and authority. As this example
illustrates, each type of SIP submittal may implicate some elements of
CAA section 110(a)(2) but not others, and rather than apply all the
stated requirements of CAA section 110(a)(2) in a strict literal sense,
as is the case for CAA section 110(a)(1), the EPA must determine how
provisions of CAA section 110(a)(2) are applicable for a particular SIP
submittal, including infrastructure SIPs.
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\1\ See e.g. 70 FR 25162 at 70 FR 25163 through 25165 (May 12,
2005), explaining the relationship between the timing requirements
of CAA section 110(a)(2)(D) versus CAA section 110(a)(2)(I).
\2\ The EPA notes that this ambiguity within CAA section
110(a)(2) is heightened by the fact that various subparts of part D
set specific dates for submittal of certain types of SIP submittals
in designated nonattainment areas for various pollutants. Note, for
example, that CAA section 182(a)(1) provides specific dates for
submittal of emissions inventories for the ozone NAAQS. Some of
these specific dates are necessarily later than three years after
promulgation of the new or revised NAAQS.
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In the context of a specific NAAQS, the EPA has also historically
recognized that CAA section 110(a)(2) should also be read and
interpreted in a logical context with respect to how infrastructure SIP
submittal requirements should be structured. For example, the
monitoring requirements that a State might need to meet in its
infrastructure SIP submittal for purposes of CAA section 110(a)(2)(B)
could be very different for different pollutants, because the content
and scope of a State's infrastructure SIP submittal to meet this
element might vary by NAAQS promulgation.\3\ Thus, the EPA notes that
the best reading of CAA section 110(a)(2) can vary for each new or
revised NAAQS, and therefore, requirements for the States' attendant
infrastructure SIP submittals for each NAAQS may be different.
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\3\ For example, implementation of the 1997 PM<INF>2.5</INF>
NAAQS required the deployment of a system of new monitors to measure
ambient levels of new indicator species for the new NAAQS.
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Given this, the EPA believes that it is appropriate to interpret
the requirements of CAA section 110(a)(2) in the context of acting on
individual SIP submittals. In other words, the EPA assumes that
Congress could not have intended that each and every SIP submittal,
regardless of the NAAQS in question or the history of SIP development
for the relevant pollutant, would meet each of the requirements, or
meet each of them in the same way. Therefore, the EPA reviews
infrastructure SIP submittals against the list of elements in CAA
section 110(a)(2), but only applies the required elements for the new
or revised NAAQS. To this end, the EPA has issued guidance documents to
make recommendations to States as to how their infrastructure SIP
submittals can be structured to meet the requirements of CAA section
110(a)(2). The EPA most recently issued guidance for infrastructure
SIPs on September 13, 2013 (``2013 Infrastructure SIP Guidance'').\4\
One notable example from the 2013 Infrastructure SIP Guidance is how it
gives simpler recommendations with respect to carbon monoxide than
other NAAQS pollutants to meet the visibility requirements of CAA
section 110(a)(2)(D)(i)(II) because carbon monoxide does not affect
visibility. As a result, an infrastructure SIP submittal for any future
new or revised NAAQS for carbon monoxide need only state this fact in
order to address the visibility prong of CAA section
110(a)(2)(D)(i)(II).
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\4\ Memorandum dated September 13, 2013, from Stephen D. Page,
Director, Office of Air Quality and Planning Standards, U.S. EPA,
Subject: ``Guidance on Infrastructure State Implementation Plan
(SIP) Elements under Clean Air Act Sections 110(a)(1) and
110(a)(2).''
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Historically, the EPA has elected to use guidance in order to
explain our current best interpretation of the relevant statute in lieu
of promulgating regulations to govern CAA section 110(a)(2)
infrastructure SIP requirements. However, the CAA ultimately governs
what is required in infrastructure SIP submittals, regardless of
whether EPA has provided advance guidance speaking to such
requirements.
Section 110(a)(1) of the CAA requires States to submit to the EPA,
within three years after the promulgation of a new or revised NAAQS, a
SIP submission that meets the applicable requirements of CAA section
110(a)(2) to provide for the implementation, maintenance, and
enforcement of the new or revised NAAQS.
CAA section 110(a)(2) includes several provisions that reference
PSD-related requirements for the regulation of new and modified major
stationary sources. Specifically:
<bullet> CAA section 110(a)(2)(C) requires States to include a
program for the regulation of new and modified major stationary
sources, including a permit program as required by title I part C of
the CAA;
<bullet> CAA section 110(a)(2)(D)(i)(II) requires States to include
``adequate provisions'' to prohibit interference with any other State's
PSD program;
<bullet> CAA section 110(a)(2)(D)(ii) requires States to include
``adequate provisions'' to ensure compliance with CAA section 126,
which requires States to notify neighboring air agencies of potential
impacts from new and modified major stationary sources of air
pollution; and
<bullet> CAA section 110(a)(2)(J) requires States to meet the
applicable requirements of part C (relating to PSD).
II. Background and Withdrawal of the EPA's Prior Proposed Partial
Approval and Partial Disapproval of PSD Requirements Under CAA Sections
110(a)(2)(C), 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii), and 110(a)(2)(J)
On January 15, 2013 the EPA promulgated a revision to the
PM<INF>2.5</INF> NAAQS (2012 PM<INF>2.5</INF> NAAQS), lowering
[[Page 50744]]
the level of the primary standard to 12.0 micrograms per cubic meter
([micro]g/m\3\), while maintaining the secondary standard.\5\ The ADEQ
submitted two SIP revisions to address the infrastructure SIP
requirements in CAA sections 110(a)(1) and 110(a)(2) for the 2012
PM<INF>2.5</INF> NAAQS. This action pertains only to ADEQ's December
11, 2015 submittal, which addresses the PSD-related requirements of CAA
section 110, titled ``Arizona State Implementation Plan Revision for
the 2012 Fine Particulate Matter (PM<INF>2.5</INF>) National Ambient
Air Quality Standard'' (``2012 PM<INF>2.5</INF> I-SIP submittal'').\6\
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\5\ 78 FR 3086 (January 15, 2013).
\6\ Letter dated December 11, 2015, from Eric Massey, Director,
Air Quality Division, ADEQ, to Jared Blumenfeld, Regional
Administrator, EPA Region IX, Subject: ``Arizona Infrastructure
State Implementation Plan for the 2012 PM<INF>2.5</INF> National
Ambient Air Quality Standards.''
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On June 13, 2024,\7\ the EPA proposed to partially approve and
partially disapprove Arizona's 2012 PM<INF>2.5</INF> I-SIP submittal
with respect to the PSD-related requirements of CAA sections
110(a)(2)(C), 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii), and 110(a)(2)(J).
Our proposed partial disapproval of these elements was based, at the
time, on deficiencies we identified with respect to PSD permitting of
greenhouse gases (GHGs) in all permitting jurisdictions in Arizona, as
well as deficiencies with respect to PSD permitting of all NSR-
regulated pollutants in Pima County. Our proposed partial approval for
the PSD-related requirements of Arizona's submittal applied to those
Arizona permitting jurisdictions with a SIP-approved PSD permitting
program covering all other NSR-regulated pollutants. Our proposed
action provided a 30-day public comment period during which we received
four comments. One of the comments failed to raise issues germane to
the proposed action, which we determined did not necessitate a
response. There were three additional comments concerning the ADEQ's
PSD permitting program.\8\
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\7\ 89 FR 50245 (June 13, 2024).
\8\ Id.
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On December 18, 2025,\9\ we took final action on most of what we
proposed in our June 13, 2024 rulemaking. However, we deferred action
on the PSD-related requirements of CAA sections 110(a)(2)(C),
110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii), and 110(a)(2)(J). Consequently,
we did not respond to the comments concerning ADEQ's PSD permitting
program.
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\9\ 90 FR 59051 (December 18, 2025).
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In this proposed action, we are withdrawing our June 13, 2024
proposed action insofar as it pertained to the PSD-related requirements
of CAA sections 110(a)(2)(C), 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii),
and 110(a)(2)(J) for the 2012 PM<INF>2.5</INF> NAAQS. We are now re-
proposing partial approval and partial disapproval of these elements
based on a change in policy, as discussed in Section III of this
document. Commenters who would like the EPA to consider any comments
submitted on the June 13, 2024 proposed rule that may be relevant to
this re-proposal must resubmit such comments during the comment period
for this proposed action.
III. The EPA's Updated Policy Rationale and Summary of the EPA's
Proposed Partial Approval and Partial Disapproval
In our June 13, 2024 action, we proposed to partially disapprove
the PSD-related requirements of the Arizona I-SIP submittal for the
2012 PM<INF>2.5</INF> NAAQS based on our interpretation at that time of
CAA section 110(a)(2)(C). Historically, we have read CAA section
110(a)(2)(C) to require that each infrastructure SIP submission
demonstrate that the State and its relevant permitting authorities have
SIP-approved PSD permitting programs that meet certain ``structural''
elements for all NSR pollutants regulated under CAA title I part C, and
not just for those relevant to the new or revised NAAQS that prompted
the infrastructure SIP submittal.\10\ As we stated in our 2013 I-SIP
guidance: ``There is no specific language in the last clause of [CAA
section 110(a)(2)(C)] that restricts its application to only those
provisions of CAA title I part C that pertain to the particular new or
revised NAAQS addressed by the particular infrastructure SIP action.
Because the scope of CAA title I part C is comprehensive (covering all
pollutants subject to regulation under the CAA, including GHG), the EPA
likewise reads the unrestricted reference to CAA title I part C . . .
to mean that this provision has the same scope as CAA title I part C
itself.''
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\10\ See, e.g., 77 FR 66398 (November 5, 2012), 83 FR 42214
(August 21, 2018), and 89 FR 71830 (September 4, 2024); see also
Memorandum dated September 13, 2013, from Stephen D. Page, Director,
Office of Air Quality and Planning Standards, U.S. EPA, Subject:
``Guidance on Infrastructure State Implementation Plan (SIP)
Elements under Clean Air Act Sections 110(a)(1) and 110(a)(2),''
pages 25 through 29.
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At the same time, we have noted in rulemakings and the 2013 I-SIP
guidance that the broad scope of 110(a)(2)(C) with respect to PSD
permitting can make it difficult for air agencies and the EPA to
address substantive issues in an I-SIP submission in a reasonable and
timely fashion.\11\ We have thus found that it is reasonable to
evaluate the PSD permitting subelement of 110(a)(2)(C) on the basis
that each air agency's PSD program contains certain ``structural''
permitting provisions necessary for administration of the program. The
basic structural elements of a PSD program that the EPA looks for in
each I-SIP submission include:
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\11\ 2013 I-SIP guidance at pages 26 through 27.
1. Provisions identifying oxides of nitrogen (NO<INF>X</INF>) as
an ozone precursor;
2. Provisions to regulate PM<INF>2.5</INF>, including
condensable PM, and its precursor emissions (sulfur dioxide
(SO<INF>2</INF>) in all areas, and NO<INF>X</INF>, and/or volatile
organic compounds as appropriate);
3. Provisions to regulate PSD increments consistent with the
requirements of the EPA's PSD implementation rule for
PM<INF>2.5</INF>; and
4. Provisions to regulate GHGs.
Historically, the EPA has interpreted a submittal's adequate
satisfaction of the PSD-related requirements under CAA section
110(a)(2)(C) as extending to the PSD-related requirements of CAA
sections 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii), and 110(a)(2)(J), and
conversely, disapproval of certain PSD-related requirements under CAA
section 110(a)(2)(C) extends to the related requirements found under
CAA sections 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii), and 110(a)(2)(J).
As such, our June 13, 2024 proposed partial disapproval was based on
deficiencies with respect to the requirements for PSD permitting of
greenhouse gases (GHGs) in all Arizona permitting jurisdictions and
deficiencies with respect to PSD permitting of all NSR-regulated
pollutants in Pima County.\12\
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\12\ 89 FR 50245, June 13, 2024.
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In this proposed action, the EPA is announcing a new interpretation
of CAA sections 110(a)(2)(C), 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii),
and 110(a)(2)(J), such that, for the PSD-related requirements,
infrastructure SIPs need only demonstrate that State and county PSD
permitting programs adequately regulate the pollutant(s) for which the
I-SIP is being submitted. This new position reflects a change in policy
as to the basic structural elements of a PSD permitting program
required to adequately satisfy the relevant requirements of CAA
sections 110(a)(2)(C), 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii), and
110(a)(2)(J). However, the EPA believes that this new interpretation
better aligns with the overall purpose of the statute. In particular,
this interpretation better aligns with the language in CAA section
[[Page 50745]]
110(a)(1), which states that within three years of promulgation of a
new NAAQS, States are required to submit a plan that provides for
``implementation, maintenance, and enforcement of such. . . standard''
(emphasis added). The fact that CAA section 110(a)(1) specifically
states that the obligation is for ``such . . . standard,'' referencing
the NAAQS that triggered the submittal, suggests that Congress intended
to limit the scope of the obligation to just the newly promulgated
NAAQS.\13\ In addition, the fact that CAA section 110(a)(1)
specifically ties the obligation to submit a new plan to a period of
time immediately following the promulgation of a new NAAQS also
supports EPA's new interpretation that the obligation for the I-SIP
relates just to the new standard. The EPA has the discretion and
authority to change policy. In FCC v. Fox Television Stations, Inc.,
the U.S Supreme Court plainly stated that an agency is free to change a
prior policy and ``need not demonstrate . . . that the reasons for the
new policy are better than the reasons for the old one; it suffices
that the new policy is permissible under the statute, that there are
good reasons for it, and that the agency believes it to be better.''
\14\
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\13\ Relatedly, we note that there is no NAAQS for GHGs that
triggers a submittal under CAA section 110(a)(1).
\14\ 566 U.S. 502, 515 (2009) (referencing Motor Vehicle Mfrs.
Ass'n of United States, Inc. v. State Farm Mut. Auto. Ins. Co., 463
U.S. 29 (1983)). See also Perez v. Mortgage Bankers Ass'n, 135 S.
Ct. 1199 (2015).
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The EPA's new policy is that for the PSD-related requirements of
CAA sections 110(a)(2)(C), 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii), and
110(a)(2)(J), infrastructure SIP submittals need only demonstrate that
State and county PSD permitting programs adequately regulate the
pollutant(s) for which the I-SIP is being submitted. The EPA believes
that this new interpretation better aligns with the requirements of the
statute, in particular, that infrastructure SIP submissions demonstrate
adequate provisions against the relevant portions of CAA section
110(a)(2), but only to the extent they are necessary to assure the
implementation, maintenance, and enforcement of the specific NAAQS for
which an infrastructure SIP is required under CAA section 110(a)(1),
and not all air pollutants considered in CAA title I part C. To this
end, the EPA now finds the following basic structural element(s)
appropriate, depending on the NAAQS the submittal is intended to
address:
1. Provisions identifying NO<INF>X</INF> as an ozone precursor;
2. Provisions to regulate PM<INF>2.5</INF>, including
condensable PM, and its precursor emissions (sulfur dioxide
(SO<INF>2</INF>) in all areas, and NO<INF>X</INF>, and/or volatile
organic compounds as appropriate); and
3. Provisions to regulate PSD increments consistent with the
requirements of the EPA's PSD implementation rule for
PM<INF>2.5</INF>.
As such, the EPA believes that as long as an infrastructure SIP
submittal for the 2012 PM<INF>2.5</INF> NAAQS demonstrates SIP-approved
provisions, for all relevant permitting authorities, in accordance with
structural elements 2 (provisions to regulate PM<INF>2.5</INF>,
including condensable PM<INF>2.5</INF>, and its precursors) and 3
(provisions to regulate PSD increments for PM<INF>2.5</INF>) listed
above, it would satisfy the PSD-related requirements of CAA sections
110(a)(2)(C), 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii), and 110(a)(2)(J).
If a permitting authority instead implements one or more of these basic
structural elements by means of a Federal PSD implementation plan, the
EPA maintains that this does not adequately satisfy the PSD-related
requirements under CAA section 110(a)(2). Because Arizona's submittal
was inconsistent with our previous interpretation of the Act and past
rulemakings on the PSD-related provisions of CAA section 110(a)(2), the
new interpretation we are proposing here does not involve a cognizable
reliance issue for Arizona.\15\
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\15\ Compare, Kentucky v. EPA, 123 F.4 447, 467-71 (4th Cir.
2025).
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Under this new interpretation of the relevant CAA provisions, we
evaluated Arizona's 2012 PM<INF>2.5</INF> I-SIP submittal and the
relevant existing provisions of the Arizona SIP for compliance with the
infrastructure SIP PSD-related requirements of CAA sections
110(a)(2)(C), 110(a)(2)(D)(i)(II), 110(a)(2)(D)(ii), and 110(a)(2)(J).
In our evaluation, we found that the State has SIP-approved provisions
that adequately satisfy the relevant structural elements 2 and 3 for
the ADEQ, MCAQD, and PCAQCD permitting authorities with respect to the
2012 PM<INF>2.5</INF> NAAQS. We also found that PDEQ does not have a
SIP-approved PSD program and instead implements a comprehensive PSD
Federal implementation plan (FIP) for PM<INF>2.5</INF> and its
precursors.
Therefore, the EPA now proposes to approve Arizona's 2012
PM<INF>2.5</INF> I-SIP submittal with respect to the 2012
PM<INF>2.5</INF> NAAQS for the following CAA requirements to the extent
they apply to the PSD permitting jurisdictions of ADEQ, MCAQD, and
PCAQCD:
<bullet> CAA section 110(a)(2)(C)--Program for regulation of new
and modified major source stationary sources;
<bullet> CAA section 110(a)(2)(D)(i)(II)--Interference with PSD
(prong 3);
<bullet> CAA section 110(a)(2)(D)(ii)--Interstate pollution
abatement, CAA section 126; and
<bullet> CAA section 110(a)(2)(J)--PSD.
The EPA also proposes to disapprove Arizona's 2012 PM<INF>2.5</INF>
I-SIP submittal with respect to the 2012 PM<INF>2.5</INF> NAAQS for the
same CAA requirements to the extent they apply to the PSD permitting
jurisdiction of PDEQ.
Although the Arizona SIP remains deficient with respect to PSD
permitting of PM<INF>2.5</INF> and its precursors in the PDEQ
permitting jurisdiction, as described, these deficiencies are
adequately addressed by an existing FIP. If finalized, this disapproval
of Arizona's SIP would not create any new consequences for Arizona, the
county agency, or the EPA, as the county agency already implements the
EPA's Federal PSD program at 40 CFR 52.21, pursuant to delegation
agreements, for PM<INF>2.5</INF> and its precursors. This disapproval,
if finalized, would also not result in any offset or highway sanctions,
which are not triggered by disapprovals of infrastructure SIPs under
CAA section 110(a)(2).
IV. Request for Public Comments
The EPA is soliciting public comments on this proposed rulemaking.
We will accept comments from the public for the next 30 days. We will
consider any comments received before taking final action.
V. Statutory and Executive Order Reviews
Under the CAA, the Administrator is required to approve a SIP
submission that complies with the provisions of the Act and applicable
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in
reviewing SIP submissions, the EPA's role is to review State choices,
and approve those choices if they meet the minimum criteria of the Act.
Accordingly, this proposed rulemaking proposes to partially approve and
partially disapprove State law as meeting Federal requirements and does
not impose additional requirements beyond those imposed by State law.
Additional information about these statutes and Executive Orders
can be found at <a href="https://www.epa.gov/laws-regulations/laws-and-executive-orders">https://www.epa.gov/laws-regulations/laws-and-executive-orders</a>.
A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review (58 FR 51735,
October 4, 1993)
This action is not a significant regulatory action and was
therefore not submitted to the Office of Management and Budget (OMB)
for review.
[[Page 50746]]
B. Executive Order 14192: Unleashing Prosperity Through Deregulation
(90 FR 9065, February 6, 2025)
This action is not expected to be an Executive Order 14192
regulatory action because this action is not significant under
Executive Order 12866.
C. Paperwork Reduction Act (PRA) (44 U.S.C. 3501et seq.)
This action does not impose an information collection burden under
the PRA because this action does not impose additional requirements
beyond those imposed by State law.
D. Regulatory Flexibility Act (RFA) (5 U.S.C. 601et seq.)
I certify that this action will not have a significant economic
impact on a substantial number of small entities under the RFA. This
action will not impose any requirements on small entities beyond those
imposed by State law.
E. Unfunded Mandates Reform Act (UMRA) (Pub. L. 104-4)
This action does not contain any unfunded mandate as described in
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect
small governments. This action does not impose additional requirements
beyond those imposed by State law. Accordingly, no additional costs to
State, local, or Tribal governments, or to the private sector, will
result from this action.
F. Executive Order 13132: Federalism (64 FR 43255, August 10, 1999)
This action does not have federalism implications. It will not have
substantial direct effects on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government.
G. Executive Order 13175: Coordination With Indian Tribal Governments
(65 FR 67249, November 9, 2000)
This action does not have Tribal implications, as specified in
Executive Order 13175, because the SIP is not approved to apply on any
Indian reservation land or in any other area where the EPA or an Indian
Tribe has demonstrated that a Tribe has jurisdiction, and will not
impose substantial direct costs on Tribal governments or preempt Tribal
law. Thus, Executive Order 13175 does not apply to this action.
H. Executive Order 13045: Protection of Children From Environmental
Health Risks and Safety Risks (62 FR 19885, April 23, 1997)
The EPA interprets Executive Order 13045 as applying only to those
regulatory actions that concern environmental health or safety risks
that the EPA has reason to believe may disproportionately affect
children, per the definition of ``covered regulatory action'' in
section 2-202 of the Executive Order. Therefore, this action is not
subject to Executive Order 13045 because it merely proposes to
partially approve and partially disapprove State law as meeting Federal
requirements. Furthermore, the EPA's Policy on Children's Health does
not apply to this action.
I. Executive Order 13211: Actions That Significantly Affect Energy
Supply, Distribution, or Use (66 FR 28355, May 22, 2001)
This action is not subject to Executive Order 13211, because it is
not a significant regulatory action under Executive Order 12866.
J. National Technology Transfer and Advancement Act (NTTAA) (15 U.S.C.
272 Note)
Section 12(d) of the NTTAA directs the EPA to use voluntary
consensus standards in its regulatory activities unless to do so would
be inconsistent with applicable law or otherwise impractical. The EPA
believes that this action is not subject to the requirements of section
12(d) of the NTTAA because application of those requirements would be
inconsistent with the CAA.
List of Subjects in 40 CFR Part 52
Environmental protection, Air pollution control, Incorporation by
reference, Intergovernmental relations, Nitrogen Dioxide, Particulate
matter, Reporting and recordkeeping requirements, Volatile organic
compounds.
(Authority: 42 U.S.C. 7401 et seq.)
Dated: July 21, 2026.
Michael Martucci,
Acting Regional Administrator, Region IX.
[FR Doc. 2026-16083 Filed 8-5-26; 8:45 am]
BILLING CODE 6560-50-P
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</html>Indexed from Federal Register on August 6, 2026.
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.