Rule2026-20736
Air Plan Approval; Michigan; Clean Data Determination for the Berrien, MI and Muskegon, MI Areas for the 2015 Ozone Standards
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 9, 2026
Effective
October 9, 2026
Issuing agencies
Environmental Protection Agency
Abstract
The U.S. Environmental Protection Agency (EPA) is determining under the Clean Air Act (CAA) that the Berrien County and Muskegon County, Michigan nonattainment areas have attained the 2015 ozone National Ambient Air Quality Standards (NAAQS). This determination, informally known as a clean data determination, is based upon complete, quality assured, and certified ambient air monitoring data for the 2023-2025 design value period showing that the areas achieved attainment of the 2015 ozone NAAQS. This clean data determination also relies upon the Michigan Department of Environment, Great Lakes, and Energy's (EGLE's) exceptional events request submitted to the EPA on December 26, 2025, and which the EPA concurred on January 12, 2026. As a result of this determination, the EPA is suspending the requirements for the Berrien and Muskegon areas to submit attainment demonstrations and associated Reasonably Available Control Measures (RACM), Reasonable Further Progress (RFP) plans, contingency measures for failure to attain or make reasonable progress, and other planning State Implementation Plans (SIPs) related to attainment of the 2015 ozone NAAQS for as long as the areas continue to attain the 2015 ozone NAAQS.
Full Text
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<title>Federal Register, Volume 91 Issue 195 (Friday, October 9, 2026)</title>
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[Federal Register Volume 91, Number 195 (Friday, October 9, 2026)]
[Rules and Regulations]
[Pages 64623-64628]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-20736]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[EPA-R05-OAR-2026-1354; FRL-13264-02-R5]
Air Plan Approval; Michigan; Clean Data Determination for the
Berrien, MI and Muskegon, MI Areas for the 2015 Ozone Standards
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: The U.S. Environmental Protection Agency (EPA) is determining
under the Clean Air Act (CAA) that the Berrien County and Muskegon
County, Michigan nonattainment areas have attained the 2015 ozone
National Ambient Air Quality Standards (NAAQS). This determination,
informally known as a clean data determination, is based upon complete,
quality assured, and certified ambient air monitoring data for the
2023-2025 design value period showing that the areas achieved
attainment of the 2015 ozone NAAQS. This clean data determination also
relies upon the Michigan Department of Environment, Great Lakes, and
Energy's (EGLE's) exceptional events request submitted to the EPA on
December 26, 2025, and which the EPA concurred on January 12, 2026. As
a result of this determination, the EPA is suspending the requirements
for the Berrien and Muskegon areas to submit attainment demonstrations
and associated Reasonably Available Control Measures (RACM), Reasonable
Further Progress (RFP) plans, contingency measures for failure to
attain or make reasonable progress, and other planning State
Implementation Plans (SIPs) related to attainment of the 2015 ozone
NAAQS for as long as the areas continue to attain the 2015 ozone NAAQS.
DATES: This final rule is effective on October 9, 2026.
ADDRESSES: The EPA has established a docket for this action under
Docket ID No. EPA-R05-OAR-2026-1354. 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, i.e.,
Confidential Business Information (CBI), Proprietary Business
Information (PBI), 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 either
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 information.
FOR FURTHER INFORMATION CONTACT: Neena Nallaballi, Air and Radiation
Division (AR18J), Environmental Protection Agency, Region 5, 77 West
Jackson Boulevard, Chicago, Illinois 60604, telephone number: (312)
353-1770, email address: <a href="/cdn-cgi/l/email-protection#bdd3dcd1d1dcdfdcd1d1d493d3d8d8d3dcfdd8cddc93dad2cb"><span class="__cf_email__" data-cfemail="7917181515181b1815151057171c1c1718391c0918571e160f">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION: Throughout this document, the use of ``we,''
``us,'' or ``our'' is intended to refer to the EPA. We use multiple
acronyms and terms in this preamble. While this list may not be
exhaustive, to ease the reading of this preamble and for reference
purposes, the EPA defines the following terms and acronyms here:
[mu]g/m\3\ Micrograms per cubic meter
Agency United States Environmental Protection Agency
APA Administrative Procedure Act
AQI Air Quality Index
CAA Clean Air Act
EGLE Michigan Department of Environment, Great Lakes, and Energy
EMBER Expedited Modeling of Burn Events Results
EPA United States Environmental Protection Agency
GAM Generalized Additive Model
GLELC Great Lakes Environmental Law Center
MDA8 Maximum daily eight-hour average ozone concentration
NAAQS National Ambient Air Quality Standards
NPRM Notice of Proposed Rulemaking
PM<INF>2.5</INF> Particulate Matter <2.5 [micro]m in Diameter
RACM Reasonably Available Control Measures
RFP Reasonable Further Progress
SIP State Implementation Plan
U.S.C. United States Code
Table of Contents
I. Background Information
II. Response to Comments
A. Exceptional Events Demonstration
B. Clean Data Policy
[[Page 64624]]
III. Final Action
IV. Statutory and Executive Order Reviews
I. Background Information
On March 12, 2026, the EPA proposed to determine under the CAA that
the Berrien, Michigan and Muskegon, Michigan areas have attained the
2015 ozone NAAQS. The EPA's proposed determination of attainment under
the Clean Data Policy, known informally as a clean data determination,
was made after reviewing the ozone monitoring data from EGLE's
monitoring sites in the Berrien and Muskegon areas for the 2023-2025
period.\1\ An explanation of the CAA requirements, a detailed analysis
of the revisions, and the EPA's reasons for this determination were
provided in the notice of proposed rulemaking (NPRM) and will not be
restated here. This action suspends the requirements for both areas to
submit an attainment demonstration, an RFP plan, contingency measures,
and other planning requirements related to attainment of the 2015 ozone
NAAQS on the condition that both of the areas continue to attain the
2015 ozone NAAQS.
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\1\ 91 FR 12123 (Mar. 12, 2026).
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II. Response to Comments
The EPA's March 12, 2026, NPRM opened a 30-day comment period,
which closed April 13, 2026. Three comments were received. An adverse
comment was submitted by the Great Lakes Environmental Law Center
(GLELC). The remaining two comments were generally supportive.
Summaries of the adverse comments and the EPA's responses are provided
below. All comments received are included in the docket for this
action.
A. Exceptional Events Demonstrations
Comment: Commenters are concerned about excluding ozone data under
the Exceptional Events Rule because wildfire smoke impacts are no
longer rare.
Response: While the EPA agrees that wildfire smoke impacts to the
Upper Midwest have been more frequent in the last several years, the
EPA remains obligated to follow the exceptional events provisions set
forth in the CAA. Pursuant to CAA section 319(b), the EPA promulgated
the ``Exceptional Events Rule,'' codified primarily at 40 CFR 50.14,
50.1 and 51.930. These provisions set the criteria and process for
excluding air quality monitoring data directly affected by exceptional
events from the Administrator's determinations regarding exceedances or
violations of the NAAQS. The Code of Federal Regulations, at 40 CFR
50.14, further clarifies that every wildfire occurring predominantly on
wildland presumptively meets the criteria categorizing it as ``not
reasonably controllable or preventable.'' As such, wildfires constitute
natural events which affect the air quality in a way that establishes a
clear causal relationship between the event and the monitored
exceedance. Thus, the exclusion of wildfire smoke-impacted ozone data
at the Muskegon and Coloma monitors is appropriate because these events
satisfy the requirements of an exceptional events demonstration as set
forth in the CAA and the Exceptional Events Rule.
Comment: The commenters state that, ``EPA's weight of evidence
approach for assessing exceptional event demonstrations violates the
plain text of the Clean Air Act.''
Response: The EPA disagrees that the weight of evidence approach
violates the CAA. CAA section 319(b)(3)(B) requires the causal
relationship to be ``clear,'' and as explained in the preamble to the
2016 Exceptional Events Rule, it is appropriate for the EPA to consider
all relevant evidence and qualitatively ``weigh'' it based on its
relevance to the Exceptional Events Rule criterion being addressed, the
degree of certainty, its persuasiveness, and other considerations
appropriate to the individual pollutant and the nature and type of
event.\2\ Courts have confirmed that it is reasonable for the EPA to
use a ``weight of evidence'' analysis when implementing the CAA.\3\ The
weight of evidence method is an appropriate and reasonable approach
which has been used historically and successfully under key CAA
programs. The weight of evidence approach is the EPA's process for
assessing whether an exceptional events demonstration meets the
requirement for a clear causal relationship at CAA section
319(b)(3)(B)(ii).
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\2\ 81 FR 68216, 68230 (Oct. 3, 2016).
\3\ See, e.g., Envtl. Def. v. EPA, 369 F.3d 193 (2d Cir. 2004)
(upholding the EPA's approval of a State's attainment demonstration
using photochemical grid modeling and a weight of evidence
analysis), BCCA Appeal Group v. EPA, 355 F.3d 817 (5th Cir. 2003)
(finding that the EPA's conclusion that the weight of evidence
approach to approving attainment demonstrations was consistent with
the CAA, reasonable and entitled to deference).
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Furthermore, and more recently, the EPA's concurrence based on a
weight of evidence approach for evaluating exceptional events was
upheld in Sierra Club v. EPA, 161 F.4th 934 (6th Cir. 2025). The
Court's opinion states, ``the EPA met the requirement to demonstrate
that it `reasonably considered the relevant issues and reasonably
explained the decision.' ''
Even if the monitored data and/or technical analyses may not
unequivocally support the causal relationship, State agencies should
submit available information regarding the event and the monitored
exceedances or violations. It may still be possible, with a weight of
evidence approach, to clearly establish the existence of a causal
connection between the data or analyses and the event causing elevated
ozone concentrations. Under that approach, each piece of information or
analysis--favorable or unfavorable--is considered, but by itself is not
conclusive.
Comment: The commenters state that, ``It's unclear what causation
standard and burden of proof EPA applied in this proposed rule.
Whatever the causation standard and burden of proof, the Commenters
believe Michigan has failed to satisfy both the causation standard and
to meet its burden of proof.''
Response: The EPA evaluates exceptional event demonstrations on a
case-by-case basis using a weight of evidence approach to assess
whether a clear causal relationship exists between the event and the
exceedance. The ``EPA Guidance on the Preparation of Exceptional Events
Demonstrations for Wildfire Events that May Influence Ozone
Concentrations'' uses a three-tier approach for addressing the clear
causal relationship element with a wildfire ozone demonstration,
recognizing that some require more evidence to demonstrate the clear
causal relationship.\4\ Tier 3 analyses include additional evidence
beyond what is required for Tier 1 and Tier 2 demonstrations because
these events are more complex. EGLE submitted a Tier 3 demonstration
consistent with this guidance. The record includes multiple lines of
evidence showing wildfire smoke transport and ground level impacts at
the Muskegon and Coloma monitors, including: photographic evidence,
regional ozone and PM<INF>2.5</INF> Air Quality Index maps, National
Oceanic and Atmospheric Administration Hazard Mapping System Fire and
Smoke maps, Hybrid Single-Particle Lagrangian Integrated Trajectory
analyses, local and regional meteorological evidence, the presence of
elevated surface level PM<INF>2.5</INF> concentrations, the EPA's
Expedited Modeling of Burn Events Results (EMBER) screening-level
photochemical modeling analysis, the Generalized
[[Page 64625]]
Additive Model (GAM) statistical model, the EPA's Met-Adjusted Ozone
Trends statistical model, and a matching day analysis for the July 15,
2025, event day at Muskegon. Across these independent methods, results
collectively show wildfire smoke caused elevated ozone concentrations
on the event days. Using a weight of evidence approach, the EPA
concluded that EGLE met the burden of proof by successfully
demonstrating a clear causal relationship between the wildfire events
and the monitored exceedances at the Muskegon and Coloma monitors.
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\4\ <a href="https://www.epa.gov/air-quality-analysis/final-guidance-preparation-exceptional-events-demonstrations-wildfire-events">https://www.epa.gov/air-quality-analysis/final-guidance-preparation-exceptional-events-demonstrations-wildfire-events</a>.
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Comment: Several comments note that EGLE did not adequately
demonstrate the wildfire smoke was the ``proximate cause'' of the ozone
exceedances or that the ozone exceedances were ``directly due'' to
wildfire smoke and therefore do not satisfy the clear causal
connection. These include assertions that: for several event days, if
modeled smoke impacts were removed, the maximum daily eight-hour
average ozone concentration (MDA8) would be greater than the NAAQS;
wildfire smoke only added minor contributions to total ozone
concentrations as modeled by the tools; exceedances were due to local
industry or vehicles as modeled impacts were minor; not all days had
quantifiable ozone concentrations from wildfire smoke calculated; and
there were discrepancies in computed concentrations between models.
Response: For the EPA to concur on an exceptional events
demonstration and exclude data from regulatory use, CAA section 319(b)
and 40 CFR 50.14 require a clear causal relationship between the event
and the monitored exceedance. The EPA evaluates the clear causal
connection between the exceptional events and the monitored exceedances
using a weight of evidence approach and not the ``but for'' or
``proximate cause'' methods. The weight of evidence approach looks at
all the information available and evaluates how supportive and relevant
each line of evidence is to the overall clear causal relationship.
Before the 2016 Exceptional Events Rule revision, the 2007 Exceptional
Events Rule required agencies to show that there would have been no
exceedance or violation ``but for'' the event also known as the ``but
for'' criterion. In the most recent revisions to the EPA's Exceptional
Event Rule in 2016, the EPA removed the ``but for'' test so that it no
longer requires quantitative analyses intended to subtract estimated
wildfire smoke contributions from reported monitoring
concentrations.\5\ Accordingly, there is no requirement in the EPA's
current Exceptional Event Rule to (1) quantify exact wildfire
contributions, (2) show the event was the ``predominant cause,'' or (3)
rule out all other sources.
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\5\ 81 FR 68216 (Oct. 3, 2016).
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There are many factors that contribute to regional ozone
concentrations in the Midwest, such as natural emissions of precursors,
transport of ozone and precursors from distant locations, local
precursor emissions, and meteorology. On these event days, wildfire
smoke was also a contributor to elevated ozone concentrations, causing
the exceedance. The presence of routine local emissions does not
preclude a finding that wildfire smoke was the cause of the monitor
exceedance where the evidence shows a clear causal connection between
the event and the exceedance. An exceptional event may still be the
cause of an exceedance even in the presence of other sources.
The ``directly due'' concept is satisfied by the totality of
evidence showing a clear causal connection. Typically, a single
analysis may not conclusively link an exceptional event to a monitored
exceedance. The EPA therefore applies a weight of evidence approach,
evaluating multiple, independent lines of evidence collectively to
determine a clear causal relationship. This approach is reflected in
the ``EPA Guidance on the Preparation of Exceptional Events
Demonstrations for Wildfire Events that May Influence Ozone
Concentrations'' and has been upheld by the Sixth Circuit in Sierra
Club v. EPA, 161 F.4th 934 (2025).
The meteorological and statistical models and analyses have
uncertainty. Differences among model outputs do not invalidate the
demonstration because such differences are expected given that the
models use different methodologies, inputs, and parameters. As
described in the EPA's EMBER Overview document:
There is uncertainty in photochemical model estimates of fire
impacts as is true of all available methods for attributing ozone
concentrations to fire emissions. As noted in the 2016 Wildfire
Guidance, `predictions of fire impacts on air quality are complex
due to uncertainties in emissions, height of emissions, plume
temperature, and plume chemistry (including radiative impacts on
chemistry). However, with proper set-up, application, and
evaluation, air quality models can be used to indicate fire impacts
on [ozone] concentrations. Combining multiple types of analysis,
including photochemical modeling, air quality monitoring data, and
meteorological analyses, offers a comprehensive approach for
understanding wildfire effects on ozone exceedances.\6\
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\6\ <a href="https://www.epa.gov/system/files/documents/2026-06/expedited-modeling-of-burn-events-results-ember-overview-document-for-data-years-of-2021-2025.pdf">https://www.epa.gov/system/files/documents/2026-06/expedited-modeling-of-burn-events-results-ember-overview-document-for-data-years-of-2021-2025.pdf</a>.
The models are meant to estimate the magnitude of the event's
impact on the ozone exceedances, plume timing, and spatial extent. The
2016 Exceptional Events Rule does not require the exact wildfire smoke
contribution to be quantified and instead uses a weight of evidence
approach.
The results of the GAM, EMBER, and Met-Adjusted Ozone Trends models
on the event days for Muskegon County and Berrien County are supportive
of wildfire smoke impacts coupled with the additional evidence provided
in EGLE's demonstration. Although the models estimate different levels
of wildfire smoke impacts at the monitors, they consistently confirm
wildfire smoke elevated ozone concentrations and are supportive to the
overall weight of evidence.
The exceptional event rule and the EPA's exceptional events
guidance states ``The EPA does not expect an air agency to prepare all
identified analyses but only those that add to their weight of evidence
supporting the clear causal relationship.'' In this instance, EGLE
provided the appropriate level of evidence, including both a
statistical regression modeling analysis and a photochemical modeling
analysis, and the EPA determined that EGLE's demonstration included
sufficient evidence to demonstrate a clear causal relationship between
the fire and the monitored ozone exceedances.
Comment: The commenters note that EGLE relied on PMO3smoke data for
monitors 36 to 40 miles from the Muskegon and Coloma monitors which are
not representative of Muskegon County and Berrien County air quality
and that no exceptional event was proposed for the Holland monitor.
Response: The GAM tool must have a monitoring site collecting
PM<INF>2.5</INF> and ozone monitoring data to compute smoke-related
ozone residuals. The events that impacted Muskegon and Berrien Counties
in EGLE's exceptional events demonstrations were regional wildfire
smoke events, affecting large portions of the United States including
the Holland and Jenison monitors. The Muskegon and Coloma ozone
monitoring sites do not have PM<INF>2.5</INF> monitoring instruments,
so EGLE and the EPA analyzed the nearby Holland and Jenison ozone sites
that also have PM<INF>2.5</INF> data as a proxy for the Muskegon and
Coloma sites. With the large-scale
[[Page 64626]]
smoke plumes and shared shoreline meteorology patterns on the event
days, a distance of 35-40 miles is not expected to have significant
impacts on the results generated by this tool.
EGLE's decision to not request exclusion of ozone data for the
Holland ozone monitoring site is not relevant to the EPA's evaluation
of the evidence submitted by EGLE for the Berrien and Muskegon County
demonstrations.
Comment: Commenters note that Michigan did not utilize EMBER or
other tools to show contribution of the exceptional event to ozone
concentrations on July 15, 2025, compared to other pollution sources.
Response: The ``EPA Guidance on the Preparation of Exceptional
Events Demonstrations for Wildfire Events that May Influence Ozone
Concentrations'' explains that States may include a matching day
analysis, statistical regression analyses, or a photochemical analysis,
to provide additional evidence supporting a clear causal relationship
between wildfire smoke and the ozone exceedances they request to
exclude. That guidance also expressly states that the ``EPA does not
expect an air agency to prepare all identified analyses'' and that
``the submitting air agency and the EPA Regional office should discuss
the appropriate level of evidence during the initial notification
process.'' Therefore, the EPA does not require a photochemical
analysis, or an explanation for its absence, to concur on exceptional
event demonstrations.
In the EPA's response to EGLE's initial notification, the EPA
confirmed that this demonstration needed to address the Tier 3 clear
causal criterion. EGLE provided a matching day analysis and the EPA's
Met-Adjusted Ozone Trends analysis for July 15, 2025. Both analyses
demonstrate wildfire smoke impacts on the event day at the Muskegon
monitor. At the time of the EPA's decision to concur on these
exceptional events, the EPA's EMBER screening-level photochemical model
only included data for 2023, and the University of Washington's GAM
statistical model only included data through 2024.
Comment: Commenters note that the PMO3smokeTool demonstrated
wildfire smoke impacted ozone concentrations from 13.0 to 15.9 ppb and
is only representative of 15% to 20% of the total ozone concentration
on the event days, asserting that local industry and vehicles are thus
responsible for a majority of the ozone. Commenters also note that
Michigan did not demonstrate the wildfire smoke was the ``proximate''
cause of the ozone exceedances on the Muskegon event days on June 19,
2023, and June 29, 2023, and that the ``proximate cause'' of the
exceedances were industrial facilities and vehicles. The commenters
note that the tools EGLE used in their demonstrations show only a 10%
to 20% contribution of wildfire smoke to the ozone levels. They argue
that these ``relatively minor impacts'' cannot be the ``proximate
cause'' of the ozone exceedances.
Response: As described in previous responses, the 2016 Exceptional
Events Rule relies on a weight of evidence approach to demonstrate a
clear causal relationship between the events and the exceedances. Thus,
the State is not required to subtract estimated smoke impacts from
observed ozone, provide exact quantification or a ``predominant
cause,'' or rule out all other sources in order to establish that
exceedances were ``directly due'' to wildfire smoke.
Comment: The commenters state that Michigan has failed to provide
adequate public notification of the events in violation of the Clean
Air Act.
Response: The Exceptional Events Rule does not specify how States
must provide public notification of an event. EGLE has demonstrated
that they have processes in place to notify the public when there is
high confidence of adverse air quality impacts. EGLE's air quality
forecasts and near real-time continuous data provided the public notice
of ozone concentrations meeting an Air Quality Index (AQI) rating of
``Unhealthy for Sensitive Groups'' or worse on the event days after
ambient concentrations of ozone rose quickly due to the distant
Canadian fires. Data from the air monitors are provided, in near real-
time, to the EPA's AirNow website as well as EGLE's MiAir website.\7\
Additionally, AirNow's EnviroFlash is a system that sends emails to
subscribers about their daily air quality forecast and current
conditions. Air agencies issue air quality forecasts based on measured
near real-time air quality levels and weather information. The forecast
is then provided to local media, posted online, and sent out to
EnviroFlash subscribers. Furthermore, EnviroFlash allows subscribers to
opt in to receive notifications at the Unhealthy for Sensitive Groups
and higher AQI categories. EGLE maintains a robust forecasting program
and issues alerts when elevated PM<INF>2.5</INF> or ozone are expected.
Even when forecasts don't fully capture an unfolding air quality event,
AirNow, MiAir, and EnviroFlash alert the public in near real-time when
air quality does become Unhealthy for Sensitive Groups or greater.
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\7\ <a href="http://www.deqmiair.org/">http://www.deqmiair.org/</a>.
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B. Clean Data Policy
Comment: Commenters assert that while the EPA's original clean data
policy states that the EPA would annually review the data and revoke
the suspension if the area subsequently violated the standards, the
EPA's rules do not make this review mandatory or set a deadline for it.
Commenter further asserts that the EPA has not explained how a
citizens' suit to force the EPA to carry out this review should
proceed.
Response: A clean data determination suspends requirements for the
area to submit attainment demonstrations and the associated RACM, RFP
plans, contingency measures for failure to attain or make reasonable
progress and other planning SIPs related to the attainment of the
standard, for as long as the area continues to attain the standard, in
accordance with the provisions set forth at 40 CFR 51.1318. The
suspended planning requirements are suspended either until the area is
redesignated to attainment for the ozone NAAQS, at which point the
requirements no longer apply, or until the EPA determines that the area
has failed to meet the ozone NAAQS, at which point the requirements go
back into effect. The area is then required to submit the suspended
plans within the time frame established by the EPA; at that time
citizens can assess their legal options.
For the Berrien and Muskegon areas specifically, should the areas
retain their nonattainment designation, then within six months of the
areas' attainment date of August 3, 2027, the EPA would be obligated
under CAA section 181(b)(2) to determine whether the areas attained the
2015 ozone NAAQS based on monitoring data from 2024-2026.\8\ Should
those data show that an area is violating the 2015 ozone NAAQS, the EPA
would issue a CAA section 181(b)(2) finding that the areas failed to
attain by the Serious area attainment date and would be reclassified by
operation of law to the next higher classification and the areas' clean
data determinations would be rescinded.
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\8\ In this action, EPA is finalizing a clean data determination
based on monitoring data from 2023-2025.
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The Clean Data Policy set forth in the 1995 Seitz Memorandum is
codified for the 1997 ozone NAAQS, 2008 ozone NAAQS, and 2015 ozone
NAAQS at 40 CFR 51.918, 51.1118, and 51.1318, respectively. This policy
has been upheld by the D.C. Circuit and all other
[[Page 64627]]
courts that have considered it.\9\ In the recent December 5, 2025,
Sixth Circuit decision \10\ the Court upheld the EPA's authority to
approve a State's exceptional events demonstration and apply the Clean
Data Policy to an ozone nonattainment area that attained the 2015 ozone
NAAQS.
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\9\ The Court of Appeals for the District of Columbia Circuit
(D.C. Circuit) upheld EPA's rule embodying the Clean Data Policy for
the 1997 8-hour ozone standard. NRDC v. EPA, 571 F.3d 1245 (D.C.
Cir. 2009). Other courts have reviewed and considered rulemakings
applying EPA's Clean Data Policy and have consistently upheld them.
Sierra Club v. EPA, 99 F.3d 1551 (10th Cir. 1996); Sierra Club v.
EPA, 375 F. 3d 537 (7th Cir. 2004); Our Children's Earth Foundation
v. EPA, No. 04-73032 (9th Cir. June 28, 2005 (Memorandum Opinion)),
Latino Issues Forum v. EPA, Nos. 06-75831 and 08-71238 (9th Cir.
March 2, 2009 (Memorandum Opinion)).
\10\ Sierra Club v. EPA, 161 F.4th 934 (6th Cir. 2025).
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The commenters raised structural and statutory objections to the
Clean Data Policy provisions at 40 CFR 51.1318. These comments are not
relevant to the EPA's determination of attainment with respect to the
Berrien and Muskegon areas and should have been raised at the time the
2015 Ozone NAAQS implementation rule was promulgated.\11\ The 2015
ozone NAAQS and the implementing regulation were promulgated through
notice and comment rulemaking subject to the judicial review provisions
of CAA section 307(b). A petition for review must be filed within sixty
days from the date of notice of such promulgation appears in the
Federal Register. No comments were submitted regarding provisions of 40
CFR 51.1318 during the comment period for the 2015 ozone NAAQS
implementation rule. Therefore, these comments fall outside the scope
of this action.
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\11\ 83 FR 62998 (Dec. 3, 2018).
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III. Final Action
The EPA is determining under the CAA that the Berrien and Muskegon
areas in Michigan have attained the 2015 ozone NAAQS. This clean data
determination is based upon complete, quality assured, and certified
ambient air monitoring data for the 2023-2025 design value period
showing that those areas achieved attainment of the 2015 ozone NAAQS.
This clean data determination relies on EGLE's exceptional events
request submitted to the EPA on December 26, 2025, which the EPA
concurred on January 12, 2026. As a result of this determination, the
requirements for the area to submit attainment demonstrations and
associated RACM, RFP plans, contingency measures for failure to attain
or make reasonable progress and other planning SIPs related to
attainment of the 2015 ozone NAAQS, are suspended for as long as the
areas continue to attain the 2015 ozone NAAQS.
In accordance with 5 U.S.C. 553(d) of the Administrative Procedure
Act (APA), the EPA finds there is good cause for this action to become
effective immediately upon publication. The immediate effective date
for this action is authorized under 5 U.S.C. 553(d)(1). Section
553(d)(1) of the APA provides that final rules shall not become
effective until 30 days after publication in the Federal Register
``except . . . a substantive rule which grants or recognizes an
exemption or relieves a restriction.'' The purpose of this provision is
to ``give affected parties a reasonable time to adjust their behavior
before the final rule takes effect.'' \12\ However, when the Agency
grants or recognizes an exemption or relieves a restriction, affected
parties do not need a reasonable time to adjust because the effect is
not adverse. The EPA has determined that this rule relieves a
restriction because this rule suspends the requirements for the area to
submit attainment demonstrations and associated RACM, RFP plans,
contingency measures for failure to attain or make reasonable progress
and other planning SIPs related to attainment of the 2015 ozone NAAQS,
for as long as the area continues to attain the 2015 ozone NAAQS. For
this reason, the EPA finds good cause under 5 U.S.C. 553(d)(1) for this
action to become effective on the date of publication of this action.
---------------------------------------------------------------------------
\12\ Omnipoint Corp. v. Fed. Commc'n Comm'n, 78 F.3d 620, 630
(D.C. Cir. 1996); see also United States v. Gavrilovic, 551 F.2d
1099, 1104 (8th Cir. 1977) (quoting legislative history).
---------------------------------------------------------------------------
IV. Statutory and Executive Order Reviews
Under the CAA, the Administrator is required to approve a SIP
submission that complies with the provisions of the CAA 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 CAA.
Accordingly, this final action constitutes a clean data determination
for the Berrien and Muskegon areas for the 2015 ozone NAAQS based on
air quality data resulting in suspension of certain Federal
requirements State law as meeting Federal requirements and does not
impose additional requirements beyond those imposed by State law.
A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review
This action is not a significant regulatory action and was
therefore not submitted to the Office of Management and Budget (OMB)
for review.
B. Executive Order 14192: Unleashing Prosperity Through Deregulation
This action is not an Executive Order 14192 regulatory action
because this action is not significant under Executive Order 12866.
C. Paperwork Reduction Act (PRA)
This action does not impose an information collection burden under
the PRA.
D. Regulatory Flexibility Act (RFA)
I certify that this action will not have a significant economic
impact on a substantial number of small entities under the RFA (5
U.S.C. 601 et seq.). This action will not impose any requirements on
small entities beyond those imposed by state law.
E. Unfunded Mandates Reform Act (UMRA)
This action does not contain any unfunded mandate as described in
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect
small governments. The action imposes no enforceable duty on any State,
local, or Tribal governments or the private sector.
F. Executive Order 13132: Federalism
This action does not have federalism implications. It will not have
substantial direct effects on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government.
G. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments
This rule does not have Tribal implications, as specified in
Executive Order 13175. It will not have substantial direct effects on
Tribal governments. Thus, Executive Order 13175 does not apply to this
rule.
H. Executive Order 13045: Protection of Children From Environmental
Health and Safety Risks
This action is not subject to Executive Order 13045 because it is
not 3(f)(1) significant as defined in Executive Order 12866, and
because the EPA does not believe the environmental health or safety
risks addressed by this action
[[Page 64628]]
present a disproportionate risk to children because it approves a State
program.
I. Executive Order 13211: Actions That Significantly Affect Energy
Supply, Distribution, or Use
This action is not subject to Executive Order 13211 because it is
not a significant regulatory action under Executive Order 12866.
J. National Technology Transfer Advancement Act
This rulemaking does not involve technical standards.
K. Congressional Review Act
This action is subject to the Congressional Review Act, and the EPA
will submit a rule report to each House of the Congress and to the
Comptroller General of the United States. This action is not a ``major
rule'' as defined by 5 U.S.C. 804(2).
L. Judicial Review
Under section 307(b)(1) of the CAA, petitions for judicial review
of this action must be filed in the United States Court of Appeals for
the appropriate circuit by December 8, 2026. Filing a petition for
reconsideration by the Administrator of this final rule does not affect
the finality of this rule for the purposes of judicial review nor does
it extend the time within which a petition for judicial review may be
filed, and shall not postpone the effectiveness of such rule or action.
This action may not be challenged later in proceedings to enforce its
requirements. See section 307(b)(2).
List of Subjects in 40 CFR Part 52
Environmental protection, Air pollution control, Incorporation by
reference, Intergovernmental relations, Nitrogen oxides, Ozone,
Reporting and recordkeeping requirements, Volatile organic compounds.
Dated: September 25, 2026.
Anne Vogel,
Regional Administrator, Region 5.
For the reasons stated in the preamble, title 40 CFR part 52 is
amended as follows:
PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS
0
1. The authority citation for part 52 continues to read as follows:
Authority: 42 U.S.C. 7401 et seq.
0
2. In Sec. 52.1170, the table in paragraph (e) is amended by adding a
second entry for ``2015 Ozone Clean Data Determination'' before the
entry for ``2015 8-hour ozone Moderate RFP plans and motor vehicle
emission budgets'' to read as follows:
Sec. 52.1170 Identification of plan.
* * * * *
(e) * * *
EPA-Approved Michigan Nonregulatory and Quasi-Regulatory Provisions
----------------------------------------------------------------------------------------------------------------
Applicable State
Name of nonregulatory SIP geographic or submittal EPA approval date Comments
provision nonattainment area date
----------------------------------------------------------------------------------------------------------------
* * * * * * *
2015 Ozone Clean Data Berrien N/A October 9, 2026, 91 EPA's final
Determination. nonattainment area FR [Insert Federal determination suspends
(Berrien County) Register page the requirements to
and Muskegon where the document submit an attainment
nonattainment area begins]. demonstration and
(part of Muskegon other associated
County). nonattainment planning
requirements for the
Berrien and Muskegon
nonattainment areas
for as long as the
areas continue to
attain the 2015 ozone
standard.
* * * * * * *
----------------------------------------------------------------------------------------------------------------
* * * * *
[FR Doc. 2026-20736 Filed 10-8-26; 8:45 am]
BILLING CODE 6560-50-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.