Proposed Rule2026-21287
Air Quality Plan; Arizona; Pinal County Air Quality Control District; West Pinal County PM10 Nonattainment Area; Fugitive Dust Rules
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
October 19, 2026
Issuing agencies
Environmental Protection Agency
Abstract
The U.S. Environmental Protection Agency (EPA) is proposing to approve revisions to the Pinal County Air Quality Control District (PCAQCD or "District") portion of the Arizona State Implementation Plan (SIP). These revisions concern emissions of particulate matter (PM) that is 10 micrometers or smaller in diameter (PM<INF>10</INF>) from fugitive dust sources, including open areas/vacant lots, unpaved lots, unpaved roads, paved public roadways, and construction sites. We are proposing to approve local rules to regulate these emission sources under the Clean Air Act (CAA or "Act").
Full Text
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<title>Federal Register, Volume 91 Issue 200 (Monday, October 19, 2026)</title>
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[Federal Register Volume 91, Number 200 (Monday, October 19, 2026)]
[Proposed Rules]
[Pages 66043-66048]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-21287]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[EPA-R09-OAR-2026-5581; FRL-13513-01-R9]
Air Quality Plan; Arizona; Pinal County Air Quality Control
District; West Pinal County PM10 Nonattainment Area; Fugitive Dust
Rules
AGENCY: U.S. Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: The U.S. Environmental Protection Agency (EPA) is proposing to
approve revisions to the Pinal County Air Quality Control District
(PCAQCD or ``District'') portion of the Arizona State Implementation
Plan (SIP). These revisions concern emissions of particulate matter
(PM) that is 10 micrometers or smaller in diameter (PM<INF>10</INF>)
from fugitive dust sources, including open areas/vacant lots, unpaved
lots, unpaved roads, paved public roadways, and construction sites. We
are proposing to approve local rules to regulate these emission sources
under the Clean Air Act (CAA or ``Act'').
DATES: Comments must be received on or before November 18, 2026.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R09-
OAR-2026-5581 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.
[[Page 66044]]
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: Alina Batool, EPA Region IX, 75
Hawthorne St., San Francisco, CA 94105; telephone number: (415) 972-
3345; email address: <a href="/cdn-cgi/l/email-protection#d2b0b3a6bdbdbefcb3bebbbcb392b7a2b3fcb5bda4"><span class="__cf_email__" data-cfemail="791b180d161615571815101718391c0918571e160f">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION: Throughout this document, ``we,'' ``us,''
and ``our'' refer to the EPA. We use multiple abbreviations and terms
in this proposed rule. While this list may not be exhaustive, for ease
of reading and for reference purposes, the EPA defines the following
terms and acronyms here:
ADEQ--Arizona Department of Environmental Quality
BACM--best available control measures
CAA--Clean Air Act
CBI--confidential business information
CFR--Code of Federal Regulations
EPA--Environmental Protection Agency
IBR--incorporation by reference
MSM--most stringent measures
NAAQS--national ambient air quality standards
PCAQCD--Pinal County Air Quality Control District
PM--particulate matter
PM<INF>10</INF>--particulate matter 10 micrometers or smaller in
diameter
RACT--reasonably available control technology
RACM--reasonably available control measures
SIP--State Implementation Plan
TFV--threshold friction velocity
TSD--technical support document
Table of Contents
I. Executive Summary
A. What action is the EPA taking?
B. What is the legal authority and what are the requirements?
II. Background
A. PM<INF>10</INF> NAAQS
B. Area Description
III. Summary of Arizona's Submittal
A. What did Arizona submit?
B. Are there other related submittals or actions?
IV. The EPA's Evaluation of Arizona's Submittal
A. How is the EPA evaluating the submittal?
B. Does the submittal meet the evaluation criteria?
C. Proposed Action and Public Comment
V. Incorporation by Reference
VI. Statutory and Executive Order Reviews
I. Executive Summary
A. What action is the EPA taking?
The EPA is proposing to approve a February 13, 2023 SIP submittal
from Arizona that includes amendments to fugitive dust rules and
related test methods for the West Pinal County portion of the Arizona
SIP. Table 1 lists the new or amended rules from the submittal that we
are proposing to approve from the PCAQCD Code of Regulations.
Table 1--PCAQCD Rules Submitted for SIP-Approval
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Rule section Rule title Adopted/amended Submitted
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Chapter 4, Article 1: West Pinal PM ``Serious'' NAA Fugitive Dust
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4-1-010................................. General Applicability........... 1/25/2023 2/13/2023
4-1-015................................. Exemptions...................... 1/25/2023 2/13/2023
4-1-020................................. Definitions..................... 1/25/2023 2/13/2023
4-1-030................................. Standards....................... 1/25/2023 2/13/2023
4-1-040................................. Recordkeeping................... 1/25/2023 2/13/2023
4-1-045................................. Reporting Requirements.......... 1/25/2023 2/13/2023
4-1-050................................. Records Retention............... 1/25/2023 2/13/2023
4-1-060................................. Violations...................... 1/25/2023 2/13/2023
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Chapter 4, Article 3: Construction Sites--Fugitive Dust
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4-3-160................................. General Provisions--West Pinal 1/25/2023 2/13/2023
PM10 Nonattainment Area.
4-3-170................................. Definitions..................... 1/25/2023 2/13/2023
4-3-180................................. Dust Generating Operations-- 1/25/2023 2/13/2023
Standards, Application, Permit,
Recordkeeping and Training
Requirements.
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Chapter 4, Article 9: Test Methods
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4-9-310................................. Test Methods for Stabilization 1/25/2023 2/13/2023
for Unpaved Shoulders and
Medians of Paved Roads.
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These revisions were submitted to support Arizona's attainment plan
for the West Pinal County PM<INF>10</INF> nonattainment area, including
to meet requirements for Best Available Control Measures (BACM) and
Most Stringent Measures (MSM). The rules from PCAQCD, Code of
Regulations, Chapter 4, Article 1, Sections 4-1-010, 4-1-015, 4-1-020,
4-1-030, 4-1-040, 4-1-045, 4-1-050, and 4-1-060, ``West Pinal
PM<INF>10</INF> Serious NAA Fugitive Dust,'' (``Article 1'') regulate
PM and PM<INF>10</INF> emissions from ``non-traditional'' sources of
fugitive dust: open areas/vacant lots, vehicle use in open areas/vacant
lots, weed abatement, unpaved lots, unpaved roads, and paved public
roadways. The rules from PCAQCD, Code of Regulations Chapter 4, Article
3, Sections 4-3-160, 4-3-170, and 4-3-180 ``Construction Sites--
Fugitive Dust,'' (``Article 3'') regulate PM and PM<INF>10</INF>
emissions from dust generating activities performed at construction
sites. Finally, the rule from PCAQCD, Code of Regulations Chapter 4,
Article 9, Section 4-9-310 ``Test Methods,'' (``Article 9'')
establishes test methods that are relied upon by Articles 1 and 3 for
determining compliance with rule requirements. Additionally, we are
proposing to approve the rescission of PCAQCD, Code of Regulations,
Chapter 4, Article 3, Section 4-3-190, ``Violations,'' adopted October
28, 2015, (``Section 4-1-190'') from the SIP.
If finalized as proposed, the rules listed in Table 1 of this
document will be incorporated into the federally enforceable portion of
the Arizona SIP and Section 4-3-190 will be removed from the Arizona
SIP.
[[Page 66045]]
B. What is the legal authority and what are the requirements?
We are proposing this action under section 110 of the CAA. Pursuant
to CAA section 110(a), States are required to submit SIPs to the EPA
that provide for the implementation, maintenance, and enforcement of
the national ambient air quality standards (NAAQS). CAA section 110(k)
requires SIPs to meet certain procedural requirements and requires the
EPA to approve or disapprove SIP submissions. CAA section 110(l)
requires States to provide public notice and an opportunity for public
hearing of SIP revisions prior to their submittal and prohibits the EPA
from approving any SIP revisions that would interfere with attainment
or maintenance of a NAAQS, reasonable further progress, or other
applicable requirements of the CAA. If a SIP submittal meets all the
applicable CAA requirements, then the EPA must approve the submittal
under CAA section 110(k)(3).
For this submittal to be approved, we must consider CAA
requirements related to the emissions limitations in the submitted
rules. CAA sections 110(a)(2)(A) and 302(k) require emissions
limitations in the SIP to be enforceable and continuous, respectively.
CAA section 172(c)(6) requires SIPs for nonattainment areas ``include
enforceable emissions limitations, and such other control measures
means or techniques . . . as well as schedules and timetables for
compliance, as may be necessary or appropriate to provide for
attainment of such standard in such area by the applicable attainment
date . . . .'' Also, 40 CFR part 51, subpart K, requires SIPs to
contain legally enforceable procedures for monitoring the status of
compliance with the requirements in the control strategy. Finally,
while these rules were submitted to meet BACM requirements under CAA
section 189(b)(1)(B) and MSM requirements under CAA section 188(e), we
are not evaluating them for BACM or MSM in this rulemaking action. We
will evaluate BACM and MSM in a separate Federal Register notice in the
context of the broader attainment plan action for the West Pinal County
PM<INF>10</INF> nonattainment area.
We are proposing that this submittal meets all applicable CAA
requirements and are proposing to fully approve it under CAA section
110(k)(3).
II. Background
A. PM10 NAAQS
The EPA establishes the NAAQS for certain ambient air pollutants at
levels required to protect public health and welfare. Emissions of
PM<INF>10</INF> contribute to effects that are harmful to human health
and the environment, including premature mortality, aggravation of
respiratory and cardiovascular disease, decreased lung function,
visibility impairment, and damage to vegetation and ecosystems.
Accordingly, the EPA revised the NAAQS for particulate matter on July
1, 1987, replacing the standards for total suspended particulates,
which are particles 30 micrometers or smaller in diameter, with new
standards applying only to PM<INF>10</INF>.\1\ In revising the NAAQS
for particulate matter, we established a 24-hour standard of 150
micrograms per cubic meter ([micro]g/m\3\), as well as an annual
standard that was subsequently revoked in 2006.\2\
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\1\ 52 FR 24634 (Jul. 1, 1987).
\2\ 71 FR 61144 (Oct. 17, 2006).
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B. Area Description
On May 31, 2012, the EPA designated a portion of state lands in
western Pinal County, Arizona, as nonattainment for the 1987
p.m.<INF>10</INF> NAAQS.\3\ The West Pinal County PM<INF>10</INF>
nonattainment area encompasses approximately 1,325 square miles lying
within a basin characterized by low desert valleys between the Phoenix
and Tucson metropolitan areas. It includes all or portions of the
incorporated cities and towns of Apache Junction, Casa Grande,
Coolidge, Eloy, Florence, Queen Creek, and Maricopa, with a population
of approximately 343,788 based upon July 1, 2017 U.S. Census Bureau
data. Average elevation in the nonattainment area is 1,403 feet above
sea level, with elevations of up to 6,441 feet directly east of the
nonattainment area, which becomes more mountainous.
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\3\ 77 FR 32024 (May 31, 2012). The boundaries for the West
Pinal County nonattainment area are described in 40 CFR 81.303.
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The West Pinal County PM<INF>10</INF> nonattainment area was
originally classified as ``Moderate'' nonattainment on May 31, 2012,
with an attainment date of December 31, 2018. CAA section 188(b)(2)
requires the EPA to determine whether a PM<INF>10</INF> nonattainment
area classified as Moderate has attained the 1987 24-hour
PM<INF>10</INF> NAAQS by the area's attainment date. If the EPA
determines that a Moderate area has not attained the NAAQS by the
relevant attainment date, then the area shall be reclassified as a
Serious area by operation of law. On June 24, 2020, we took final
action to determine that the West Pinal County PM<INF>10</INF>
nonattainment area did not attain the 1987 24-hour PM<INF>10</INF>
NAAQS, and as a result, it was reclassified to Serious nonattainment by
operation of law.\4\
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\4\ 85 FR 37756 (Jun. 24, 2020).
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III. Summary of Arizona's Submittal
A. What did Arizona submit?
On February 13, 2023, the Arizona Department of Environmental
Quality (ADEQ) submitted amended rules from PCAQCD to the EPA for
approval into the West Pinal County portion of the Arizona SIP. The
rule amendments were adopted by PCAQCD on January 25, 2023, and
submitted to support Arizona's attainment plan for the West Pinal
County PM<INF>10</INF> nonattainment area. Table 1 of this document
lists the adopted and/or amended rules that were submitted and that we
are proposing to approve into the SIP. The submittal also requests to
rescind Section 4-3-190, which was repealed by the Pinal County Board
of Supervisors on January 25, 2023.\5\ Additionally, the submittal
requests that we approve Section 4-3-320, ``Test Methods for
Stabilization for Unpaved Roads and Unpaved Parking Lots,'' adopted on
June 3, 2009, (``Section 4-3-320'') and 4-3-340, ``Visual Opacity Test
Methods,'' adopted on June 3, 2009, (``Section 4-3-340''). On August
13, 2023, this submittal was deemed by operation of law to be complete.
We have reviewed the submittal to ensure it meets the completeness
criteria in 40 CFR part 51, appendix V.
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\5\ Resolution No. 012523-AQ.
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B. Are there other related submittals or actions?
We approved earlier versions of the rules in Article 1 and Article
3 into the SIP in 2017.\6\ If we finalize this rulemaking as proposed,
then the January 25, 2023 versions of the rules from Article 1 and
Article 3, as listed in Table 1 of this document, will replace the
previously approved versions in the SIP.
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\6\ 82 FR 20267 (May 1, 2017). These earlier versions were
adopted by PCAQCD on October 28, 2015, and submitted to the EPA on
December 21, 2015.
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Regarding test methods from Article 9, Section 4-9-310, ``Test
Methods for Stabilization for Unpaved Shoulders and Medians of Paved
Roads,'' adopted on January 25, 2023, (``Section 4-9-310'') has not
been previously approved into the SIP. However, in 2010, we previously
approved the currently submitted versions of Sections 4-9-320 and 4-9-
340.\7\ That is, Sections 4-9-320 and 4-9-340 are already approved into
the SIP, and no further action from the EPA is needed related to the
current
[[Page 66046]]
request to approve them into the SIP. PCAQCD has not amended these
rules locally.
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\7\ 75 FR 17307 (Apr. 6, 2010).
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Finally, PCAQCD repealed Section 4-3-190 that we previously
approved into the SIP in 2017.\8\
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\8\ 82 FR 20267 (May 1, 2017).
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IV. The EPA's Evaluation of Arizona's Submittal
A. How is the EPA evaluating the submittal?
Emission limitations in the SIP must be enforceable, continuous,
and must not interfere with applicable requirements concerning
attainment and reasonable further progress or other CAA
requirements.\9\ Additionally, 40 CFR part 51, subpart K, requires SIPs
to have enforceable procedures for monitoring the status of compliance
with the requirements in the control strategy.
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\9\ See, CAA sections 110(a)(2), 302(k) and 110(l),
respectively.
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The PCAQCD regulates a PM<INF>10</INF> nonattainment area
classified as Serious for the 1987 24-hour PM<INF>10</INF> NAAQS. In
Serious nonattainment areas, SIPs must implement BACM, including Best
Available Control Technology.\10\ In addition, because Arizona is
seeking a five-year extension of the attainment date, the SIP must also
implement MSM.\11\ These evaluations are included in the context of the
broader attainment plan rulemaking and are not included in this
rulemaking. In this rulemaking, we are evaluating these rules for
approval into the SIP under CAA section 110 requirements.
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\10\ CAA section 189(b)(1)(B).
\11\ CAA section 188(e).
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Our evaluation also relies on relevant guidance and policy
documents to evaluate enforceability and revisions/relaxation
requirements.\12\
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\12\ See, ``State Implementation Plans; General Preamble for the
Implementation of Title I of the Clean Air Act Amendments of 1990,''
57 FR 13498 (Apr. 16, 1992); 57 FR 18070 (Apr. 28, 1992); ``Guidance
Document for Correcting Common VOC & Other Rule Deficiencies,'' EPA
Region 9, August 21, 2001 (the Little Bluebook); ``State
Implementation Plans for Serious PM-10 Nonattainment Areas, and
Attainment Date Waivers for PM-10 Nonattainment Areas Generally;
Addendum to the General Preamble for the Implementation of Title I
of the Clean Air Act Amendments of 1990,'' 59 FR 41998 (Aug. 16,
1994); ``PM-10 Guideline Document,'' EPA 452/R-93-008, April 1993;
and ``Fugitive Dust Background Document and Technical Information
Document for Best Available Control Measures,'' EPA 450/2-92-004,
September 1992.
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B. Do the submittals meet the evaluation criteria?
We evaluated these rules to ensure they meet CAA requirements and
are consistent with relevant guidance regarding enforceability and SIP
revisions.
1. Article 1 Rules
Article 1 applies to ``non-traditional'' fugitive dusts sources in
the West Pinal County PM<INF>10</INF> nonattainment area: open areas/
vacant lots, vehicle use in open areas/vacant lots, unpaved lots, weed
abatement and/or trash removal, unpaved roads, and paved public
roadways. Affected owners and operators are required to implement
control measures that will meet visible emission and surface
stabilization standards. Compliance with stabilization and visible
emission standards are determined through applicable test methods in
Article 9.
Each of the regulated activities has specific standards and control
measures that must be met. For visible emission standards, either a 20
percent opacity limit applies or visible emissions, including fugitive
dust, are prohibited from going beyond the property line. Owners and
operators choose the stabilization standard they will meet from a list
of options, such as maintaining a soil crust, meeting a minimum
threshold friction velocity (TFV) \13\ limit, covering the area with a
certain percentage of vegetative cover, or meeting silt loading \14\
limits. Owners and operators then choose a control measure to implement
for each regulated activity from a menu of options, such as
establishing vegetative cover, applying dust suppressants, applying
water, restoring the area to an undisturbed native condition,
establishing barriers to prevent unauthorized vehicle access, paving
parking lots, and applying and maintaining surface gravel.
Additionally, disturbed surface areas of 0.10 acres (4,356 square feet)
or greater must sign up to receive the Pinal County Dust Control
Forecast and ensure control measures are implemented on the day prior
and day of a high dust risk forecast.
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\13\ TFV relates to a material's susceptibility to erosion from
wind. Materials with a higher TFV are less susceptible to wind
erosion and are associated with lower fugitive dust emissions.
\14\ ``Silt'' refers to aggregate material (dirt, sand, rock)
that has a particle size of 75 micrometers or less. ``Silt loading''
refers to the concentration of silt on unpaved surfaces. Higher silt
loading, that is, higher concentrations of smaller particles, is
associated with higher fugitive dust emissions.
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Article 1 includes a new standard for paving existing unpaved
roadways. Beginning January 1, 2024, each city, county, or state agency
with primary responsibility for any existing unpaved road within the
West Pinal County PM<INF>10</INF> nonattainment area was required to
annually pave an average of 20 percent of unpaved roads within the
agency's jurisdiction.\15\ Further, if the EPA determines the West
Pinal County PM<INF>10</INF> nonattainment area failed to make
reasonable further progress, or to attain the PM<INF>10</INF> NAAQS by
the attainment date, the rules include a contingency measure where any
public unpaved road with average daily trips of 26 or more will have a
speed limit of 15 miles per hour.
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\15\ Up to a maximum of 5 cumulative miles for each agency.
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For paved public roads, Article 1 establishes new standards by
requiring street sweeping to be done by certified street sweepers and
establishing paved road development standards that specify minimum
surface stabilization standards for road shoulders.
Each person subject to Article 1 is required to compile and retain
records that provide evidence of control measure application (i.e.,
receipts and/or purchase records). The records must describe the type
of treatment or control measure, extent of coverage, and date applied.
Records must be available to the District upon request and maintained
for at least two years. Agencies subject to the road paving requirement
must submit annual progress reports by January 30 of each year related
to the annual road paving requirements and the number of paved roads
with unpaved shoulders.
Overall, the visible emission limits, stabilization standards, and
control measures are tailored to minimizing fugitive dust from each
type of regulated activity, result in continuous emissions limitations,
and the associated recordkeeping and reporting requirements are
sufficient to meet the enforceability requirements of CAA sections
110(a)(2)(A) and 172(c)(6) and 40 CFR part 51, subpart K. The
amendments strengthen the existing SIP, consistent with CAA section
110(l), by expanding existing control measures, such as lowering
applicability thresholds, adding or revising visible emission
standards, establishing clear timelines for when control measures must
be implemented, clarifying that control measures are considered to be
implemented when the associated visible emission and/or stabilization
standards are met, and adding new control measures for paved and
unpaved roads. Because they meet all applicable CAA requirements, we
propose approving the rules from Article 1 into the Arizona SIP.
2. Article 3 Rules
Article 3 applies to fugitive dusts sources at construction sites
within the
[[Page 66047]]
West Pinal County PM<INF>10</INF> nonattainment area. Affected owners
and operators are required to implement control measures and meet
visible emission standards and surface stabilization standards for dust
generating activities. Additionally, owners or operators are required
to obtain a dust permit when dust-generating operations at construction
sites disturb a total surface area of 0.10 acres (4,356 square feet) or
more. All permit applications must contain a dust control plan that
identifies all control measures to be implemented before, after, and
while conducting any dust-generating operation.
Sites with a dust control permit must: for each project of 5 or
more acres, have a project information sign that identifies how the
public can file a dust complaint to the District; meet dust control
training requirements once every three years from the District; except
in certain high wind conditions, implement all control measures
necessary to maintain soil stability; implement control measures
specified for each type of activity, such as active areas, demolition,
weed abatement, trackout, site grade preparation, trenching, and haul
roads; limit dust generated on the property to 20 percent opacity, and
ensure no visible emissions, including fugitive dust, go beyond the
property line; install no trespassing signs for project sites when
activities cease for 30 or more days at a time; and, on a high dust
risk day, continue to implement control measures that maintain
compliance with the applicable standards or cease dust-generating
activities and ensure disturbed surface areas are stablized for the
day. Construction sites that do not require a dust control permit are
subject to the same general control measures, visible emission
standards, and stabilization requirements but are not subject to
signage and dust control training requirements. Similar to Article 1,
owners and operators subject to Article 3 choose from a menu of options
to meet control measure requirements and surface stabilization
standards.
Any person who conducts dust-generating operations that require a
dust control permit is required to keep written records of self-
inspection on each day dust-generating operations are conducted. Self-
inspection records include daily inspections for crusted or damp soil,
trackout conditions and clean-up measures, daily water usage for dust
control measures, and dust suppressant application. Any person who
conducts dust-generating operations that do not require a dust control
permit must maintain records that provide evidence of control measure
application, by indicating the type of treatment or control measure,
extent of coverage, and date applied. Records are required to be
maintained for two years, except for construction sites at a facility
with a title V operating permit, which must maintain records for five
years.
Overall, the dust control permit requirements, visible emission
limits, stabilization standards, and control measures are tailored to
minimizing fugitive dust for each type of regulated activity, result in
continuous emission limitations, and associated recordkeeping
requirements are sufficient to meet the enforceability requirements of
CAA sections 110(a)(2)(A) and 172(c)(6) and 40 CFR part 51, subpart K.
The amendments would strengthen the existing SIP in several ways,
consistent with CAA section 110(l), including adding a visible emission
standard that prohibits visible emissions from going beyond the
property line, adding signage requirements and dust control operator
training requirements, specifying the threshold for obtaining a dust
control permit, specifying the dust generating activities that are
required to implement control measures, specifying the types of control
measures that apply to each type of dust generating activity,
specifying that control measures must be implemented at all times, and
requiring daily records of actions to reduce fugitive dust. Because
they meet all applicable CAA requirements, we are proposing to approve
the rules from Article 3 into the Arizona SIP.
3. Rescission of Section 4-3-190
Previously, if certain conditions were met, Section 4-3-190
provided an exemption from the requirements of Article 3 during high
wind conditions and emergency maintenance of flood control channels and
water retention basins. The rule amendments adopted by the District to
Article 3 on January 25, 2023, incorporate requirements that apply
during these circumstances within other provisions of Article 3 such
that removal of this section would not relax any existing SIP
requirement and is consistent with CAA section 110(l).\16\ Therefore,
we are proposing to approve this rescission request.
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\16\ See, Section 4-3-180.I.2.b, contains required control
measures during high wind events, Section 4-3-170.20, adds a
definition for ``high wind conditions,'' and Section 4-3-160.A.5.i
is a comparable exemption for emergency maintenance of flood control
channels, conditioned on implementation of all permitted control
measures.
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4. Article 9 Rules
Section 4-9-310 establishes test methods to determine whether
unpaved shoulders and medians of paved roads meet applicable surface
stabilization standards. It includes an opacity test method, silt
loading test method, and gravel depth and silt content test method.
These test methods are used to determine compliance with stabilization
standards in Article 1 and 3.
Based upon our evaluation, these test methods are enforceable and
consistent with comparable test methods established in Federal
requirements and SIP-approved fugitive dust rules in other States. We
consider their use with Articles 1 and 3 to be an appropriate
application of the test methods. The test methods ensure the associated
emission limits will meet the enforceability requirements of CAA
sections 110(a)(2)(A) and 172(c)(6) and 40 CFR part 51, subpart K,
strengthen the SIP, and would not interfere with any other CAA
requirements, consistent with CAA section 110(l). Because the rule
meets all applicable CAA requirements, we are proposing to approve
Section 4-9-310 into the Arizona SIP.
As stated above in section III.B, the EPA is not acting on Sections
4-9-320 and 4-9-340 from the state's submittal in this action. These
rules are already approved into the SIP and PCAQCD has not amended them
locally, so no further action is needed.
5. Conclusions
Based on our review, the rules proposed for approval, as listed in
Table 1 of this document, and the proposed rescission of Section 4-3-
190 meet the relevant CAA requirements. The technical support documents
(TSDs) for each article (Articles 1, 3, and 9) have more information on
our evaluation and are available in the docket for this rulemaking.
C. Proposed Action and Public Comment
As authorized in section 110(k)(3) of the Act, the EPA proposes to
approve Arizona's February 13, 2023 SIP submittal, including approving
the rules listed in Table 1 of this document into the Pinal County
portion of the Arizona SIP and the rescission of Section 4-3-190 from
the SIP, because they fulfill all relevant requirements. We will accept
comments from the public on this proposal until November 18, 2026. If
finalized as proposed, our final action will incorporate the rules
listed in Table 1 of this document into the federally enforceable SIP
and Section 4-3-190 will be removed from the SIP.
[[Page 66048]]
V. Incorporation by Reference
In this document, the EPA is proposing to include in a final EPA
rule regulatory text that includes incorporation by reference. In
accordance with requirements of 1 CFR 51.5, the EPA is proposing to
incorporate by reference PCAQD, Code of Regulations, Chapter 4, Article
1, Sections 4-1-010, ``General Applicability;'' 4-1-015,
``Exemptions;'' 4-1-020, ``Definitions;'' 4-1-030, ``Standards;'' 4-1-
040, ``Recordkeeping;'' 4-1-045, ``Reporting Requirements;'' 4-1-050,
``Records Retention;'' and 4-1-060, ``Violations;'' as amended on
January 25, 2023, which regulate fugitive dust emissions from open
areas/vacant lots, unpaved lots, weed abatement, unpaved roads, and
paved public roadways in the West Pinal County Serious PM<INF>10</INF>
Nonattainment Area. The EPA is also proposing to incorporate by
reference PCAQD, Code of Regulations, Chapter 4, Article 3, Sections 4-
3-160, ``General Provisions--West Pinal PM<INF>10</INF> Nonattainment
Area;'' 4-3-170, ``Definitions;'' and 4-3-180 ``Dust Generating
Operations: Standards, Application, Permit, Recordkeeping and Training
Requirements'' as amended on January 25, 2023, which regulate fugitive
dust emissions from construction sites in the West Pinal County Serious
PM<INF>10</INF> Nonattainment Area. The EPA is also proposing to
incorporate by reference PCAQD, Code of Regulations, Chapter 4, Article
9, Section 4-9-310, ``Test Methods for Stabilization for Unpaved
Shoulders and Medians of Paved Roads,'' as adopted on January 25, 2023,
which establishes test methods used to determine compliance with
requirements for dust generating activities contained in PCAQD, Code of
Regulations, Chapter 4, Articles 1 and 3. The EPA has made, and will
continue to make, these materials available through <a href="https://www.regulations.gov">https://www.regulations.gov</a> and at the EPA Region IX Office (please contact the
person identified in the FOR FURTHER INFORMATION CONTACT section of
this preamble for more information).
VI. 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 approve state choices,
provided that they meet the criteria of the CAA. Accordingly, this
proposed action merely proposes to approve state law as meeting federal
requirements and does not impose additional requirements beyond those
imposed by state law. For that reason, this proposed action:
<bullet> Is not a significant regulatory action subject to review
by the Office of Management and Budget under Executive Order 12866 (58
FR 51735, October 4, 1993);
<bullet> Is not an Executive Order 14192 (90 FR 9065, February 6,
2025) regulatory action because this action is not significant under
Executive Order 12866;
<bullet> Does not impose an information collection burden under the
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
<bullet> Is certified as not having a significant economic impact
on a substantial number of small entities under the Regulatory
Flexibility Act (5 U.S.C. 601 et seq.);
<bullet> Does not contain any unfunded mandate or significantly or
uniquely affect small governments, as described in the Unfunded
Mandates Reform Act of 1995 (Pub. L. 104-4);
<bullet> Does not have federalism implications as specified in
Executive Order 13132 (64 FR 43255, August 10, 1999);
<bullet> Is not subject to Executive Order 13045 (62 FR 19885,
April 23, 1997) because it proposes to approve a state program;
<bullet> Is not a significant regulatory action subject to
Executive Order 13211 (66 FR 28355, May 22, 2001); and
<bullet> Is not subject to requirements of section 12(d) of the
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272
note) because application of those requirements would be inconsistent
with the CAA.
In addition, 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. In those areas of
Indian country, the rule does not have Tribal implications and will not
impose substantial direct costs on Tribal governments or preempt Tribal
law as specified by Executive Order 13175 (65 FR 67249, November 9,
2000).
List of Subjects in 40 CFR Part 52
Environmental protection, Air pollution control, Incorporation by
reference, Intergovernmental relations, Particulate matter, Reporting
and recordkeeping requirements.
Authority: 42 U.S.C. 7401 et seq.
Dated: October 14, 2026.
Michael Martucci,
Acting Regional Administrator, Region IX.
[FR Doc. 2026-21287 Filed 10-16-26; 8:45 am]
BILLING CODE 6569-60-P
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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.