Proposed Rule2026-06442
Air Plan Approval; Wisconsin; Moderate Attainment Plan Elements for Wisconsin's 2015 Ozone Standard Areas
Primary source
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Published
April 2, 2026
Issuing agencies
Environmental Protection Agency
Abstract
The Environmental Protection Agency (EPA) is proposing to approve portions of Wisconsin's 2015 ozone National Ambient Air Quality Standard (NAAQS or standard) Moderate nonattainment area State Implementation Plan (SIP) submission for the Wisconsin portion of the Chicago, Illinois-Indiana-Wisconsin area (Kenosha County), the Milwaukee, Wisconsin area, and the Sheboygan County, Wisconsin area. The elements of the Moderate SIP submission include the reasonable further progress (RFP) demonstration and the associated motor vehicle emissions budgets (Budgets) for 2023, the motor vehicle inspection and maintenance (I/M) program, and the nonattainment new source review (NNSR) program. The EPA is also proposing to approve the base year emissions inventory as satisfying previous Marginal area requirements for these areas. The EPA is proposing to approve these portions of the State's submission as a SIP revision pursuant to section 110 and part D of the Clean Air Act (CAA) and EPA's regulations. The EPA is also initiating the adequacy process for the 2023 Budgets.
Full Text
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<title>Federal Register, Volume 91 Issue 63 (Thursday, April 2, 2026)</title>
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[Federal Register Volume 91, Number 63 (Thursday, April 2, 2026)]
[Proposed Rules]
[Pages 16605-16614]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-06442]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[EPA-R05-OAR-2025-0169; EPA-R05-OAR-2025-0170; EPA-R05-OAR-2025-0171;
FRL-13164-01-R5]
Air Plan Approval; Wisconsin; Moderate Attainment Plan Elements
for Wisconsin's 2015 Ozone Standard Areas
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: The Environmental Protection Agency (EPA) is proposing to
approve portions of Wisconsin's 2015 ozone National Ambient Air Quality
Standard (NAAQS or standard) Moderate nonattainment area State
Implementation Plan (SIP) submission for the Wisconsin portion of the
Chicago, Illinois-Indiana-Wisconsin area (Kenosha County), the
Milwaukee, Wisconsin area, and the Sheboygan County, Wisconsin area.
The elements of the Moderate SIP submission include the reasonable
further progress (RFP) demonstration and the associated motor vehicle
emissions budgets (Budgets) for 2023, the motor vehicle inspection and
maintenance (I/M) program, and the nonattainment new source review
(NNSR) program. The EPA is also proposing to approve the base year
emissions inventory as satisfying previous Marginal area requirements
for these areas. The EPA is proposing to approve these portions of the
State's submission as a SIP revision pursuant to section 110 and part D
of the Clean Air Act (CAA) and EPA's regulations. The EPA is also
initiating the adequacy process for the 2023 Budgets.
DATES: Comments must be received on or before May 4, 2026.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R05-
OAR-2025-0169 (Kenosha), EPA-R05-OAR-2025-0170 (Milwaukee), and EPA-
R05-OAR-2025-0171 (Sheboygan) at <a href="https://www.regulations.gov">https://www.regulations.gov</a>, or via
email to <a href="/cdn-cgi/l/email-protection#98f4f9f6fff5f9f6b6f5f1fbf0f9fdf4d8fde8f9b6fff7ee"><span class="__cf_email__" data-cfemail="a6cac7c8c1cbc7c888cbcfc5cec7c3cae6c3d6c788c1c9d0">[email protected]</span></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 the
docket. The EPA may publish any comment received to its public docket.
Do not submit to the EPA's docket at <a href="https://www.regulations.gov">https://www.regulations.gov</a> any
information you consider to be Confidential Business Information (CBI),
Proprietary Business Information (PBI), or other information whose
disclosure is restricted by statute. Multimedia submissions (audio,
video, etc.) must be accompanied by a written comment. The written
comment is considered the official comment and should include
discussion of all points you wish to make. The EPA will generally not
consider comments or comment contents located outside of the primary
submission (i.e., on the web, cloud, or other file sharing system). For
additional submission methods, please contact the person identified in
the FOR FURTHER INFORMATION CONTACT section. For the full EPA public
comment policy, information about CBI, PBI, 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>.
FOR FURTHER INFORMATION CONTACT: Michael Leslie, Air and Radiation
Division (AR18J), Environmental Protection Agency, Region 5, 77 West
Jackson Boulevard, Chicago, Illinois 60604, telephone number: (312)
353-6680, email address: <a href="/cdn-cgi/l/email-protection#8ae6eff9e6e3efa4e7e3e9e2ebefe6caeffaeba4ede5fc"><span class="__cf_email__" data-cfemail="4b272e3827222e65262228232a2e270b2e3b2a652c243d">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION: Throughout this document whenever ``we,''
``us,'' or ``our'' is used, we mean the EPA. This supplementary
information section is arranged as follows:
I. Background
II. Evaluation of Wisconsin's Submittal
A. 2017 Base Year Emissions Inventory
B. 15% RFP Plan
C. Motor Vehicle Emissions Budgets
D. Motor Vehicle I/M Program
E. NNSR Review
III. What action is the EPA taking?
IV. Statutory and Executive Order Reviews
I. Background
On December 28, 2015, the EPA promulgated a revised 8-hour ozone
NAAQS of 0.070 parts per million (ppm).\1\ Promulgation of a revised
NAAQS triggers a requirement for the EPA to designate all areas of the
country as nonattainment, attainment, or unclassifiable for the NAAQS.
For the ozone NAAQS, this also involves classifying any nonattainment
areas at
[[Page 16606]]
the time of designation.\2\ Ozone nonattainment areas are classified
based on the severity of their ozone levels as determined based on the
area's ``design value,'' which represents air quality in the area for
the most recent three years. The classifications for ozone
nonattainment areas are Marginal, Moderate, Serious, Severe, and
Extreme.\3\
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\1\ 80 FR 65292, October 26, 2015, codified at 40 CFR 50.19.
\2\ CAA sections 107(d)(1) and 181(a)(1).
\3\ CAA section 181(a)(1).
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Areas that the EPA designates nonattainment for the ozone NAAQS are
subject to the general nonattainment area planning requirements of CAA
section 172 and the ozone-specific planning requirements of CAA section
182. Ozone nonattainment areas in the lower classification levels have
less stringent mandatory air quality planning and control requirements
than those in higher classifications. In the EPA's December 6, 2018 (83
FR 62998), rule, ``Implementation of the 2015 National Ambient Air
Quality Standards for Ozone: Nonattainment Area State Implementation
Plan Requirements,'' known as the ``SIP Requirements Rule,'' the EPA
set forth nonattainment area requirements for the 2015 ozone NAAQS.
These requirements are codified at 40 CFR part 51 subpart CC. For
Marginal areas, a State is required to submit a baseline emissions
inventory, adopt provisions into the SIP requiring emissions statements
from stationary sources, and implement an NNSR program for the relevant
ozone NAAQS.\4\ For Moderate areas, a State needs to comply with the
Marginal area requirements, plus additional Moderate area requirements,
including the requirement to submit a modeled demonstration that the
area will attain the NAAQS as expeditiously as practicable but no later
than six years after designation, the requirement to submit an RFP
plan, the requirement to adopt and implement certain emissions controls
such as Reasonably Available Control Technology (RACT) and a Basic I/M
program, and the requirement for the greater emissions offsets for new
or modified major stationary sources under the State's NNSR program.\5\
Effective August 3, 2018, the EPA finalized the Wisconsin areas'
Marginal nonattainment designations for the 2015 ozone NAAQS.\6\
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\4\ CAA section 182(a).
\5\ CAA section 182(b).
\6\ 83 FR 25776, June 4, 2018.
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In response to a July 10, 2020, decision by the D.C. Circuit Court,
the EPA revised the 2015 ozone NAAQS Marginal nonattainment
designations for the Kenosha County and Milwaukee areas, effective July
14, 2021.\7\ This action expanded the original partial Kenosha County
boundary designation. For the Milwaukee area, the EPA revised and
expanded nonattainment designations to include the entirety of
Milwaukee and Ozaukee Counties and parts of Racine, Waukesha, and
Washington Counties. The Sheboygan County area remained the same as the
original Marginal designation.
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\7\ 86 FR 31438, June 14, 2021.
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On October 7, 2022 (87 FR 60897), pursuant to section 181(b)(2) of
the CAA, the EPA determined that the Kenosha County area, the Milwaukee
area, and the Sheboygan County area failed to attain the 2015 ozone
NAAQS by the August 3, 2021, Marginal area attainment deadline and thus
reclassified the area from Marginal to Moderate nonattainment. In that
action, the EPA established January 1, 2023, as the due date for the
State to submit all Moderate area nonattainment plan SIP requirements
applicable to newly reclassified areas.
II. Evaluation of Wisconsin's Submittal
Wisconsin submitted a SIP revision on April 2, 2025, to address the
Marginal area requirement for baseline emissions inventories and the
Moderate area requirements for Kenosha County area, the Milwaukee area,
and the Sheboygan County area under the 2015 ozone NAAQS. The submittal
contained several nonattainment plan elements, including a 2017 base
year emissions inventory for volatile organic compounds (VOC) and
oxides of nitrogen (NO<INF>X</INF>), a 15% RFP plan with 2023 VOC and
NO<INF>X</INF> motor vehicle emissions budgets, an I/M program
certification, and an NNSR certification. The 2017 base year emissions
inventories supersede and replace a prior submittal by Wisconsin on
August 3, 2021, to address Marginal area requirements for the Wisconsin
areas for the 2015 ozone NAAQS. Each of these nonattainment plan
elements is covered in further detail below. The submission also
included an attainment demonstration, a reasonably available control
measures (RACM) demonstration, and contingency measures, which will be
addressed in a separate action. Wisconsin's SIP submission and
associated supporting documents are available in the dockets for this
action, at <a href="https://www.regulations.gov">https://www.regulations.gov</a>, Docket ID No. EPA-R05-OAR-2025-
0169 (Kenosha), EPA-R05-OAR-2025-0170 (Milwaukee), and EPA-R05-OAR-
2025-0171 (Sheboygan).
A. 2017 Base Year Emissions Inventory
1. Background
CAA sections 172(c)(3) and 182(a)(1), 42 U.S.C. 7502(c)(3) and
7511a(a)(1), require States to develop and submit, as SIP revisions,
comprehensive, accurate, and complete emissions inventories for all
areas designated as nonattainment for the ozone NAAQS. This requirement
is codified at 40 CFR 51.1315, and the term ``base year inventory'' is
defined at 51.1300(p). For ozone, the base year inventory is an
estimation of actual emissions of VOC and NO<INF>X</INF> from all
sources within the boundaries of the nonattainment area.
The regulation at 40 CFR 51.1315(a) requires that the selected
inventory year be consistent with the baseline year for the RFP plan as
required by 40 CFR 51.1310(b), which states that the baseline emissions
inventory shall be the emissions inventory for the most recent calendar
year for which a complete triennial inventory is required to be
submitted to the EPA under the provisions of subpart A of 40 CFR part
51, Air Emissions Reporting Requirements (AERR), 40 CFR 51.1 through
50. For areas designated as nonattainment in 2018, the most recent
triennial inventory year conducted for the National Emissions Inventory
(NEI) pursuant to the AERR rule is 2017.\8\
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\8\ 83 FR 62998 at 63005, December 6, 2018.
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Further, 40 CFR 51.1315(c) requires emissions values included in
the base year inventory to be actual ozone season day emissions as
defined by 40 CFR 51.1300(q), which states: ``Ozone season day
emissions means an average day's emissions for a typical ozone season
work weekday. The State shall select, subject to EPA approval, the
particular month(s) in the ozone season and the day(s) in the work week
to be represented, considering the conditions assumed in the
development of RFP plans and/or emissions budgets for transportation
conformity.''
2. Wisconsin's Emissions Inventory Submittal
Wisconsin's 2017 base year emissions inventory submittal for the
2015 ozone NAAQS nonattainment areas includes VOC and NO<INF>X</INF>
emissions estimates for the following source categories: point sources,
area sources, onroad mobile sources, and nonroad mobile sources.
Point Sources
Point sources are industrial, commercial, or institutional
stationary facilities, typically located at permanent sites, which emit
specific pollutants in large enough quantities to warrant
[[Page 16607]]
individual quantification. Wisconsin created the point source emissions
inventory using annually reported point source emissions, the EPA's
Clean Air Markets Program Data (CAMPD), and approved EPA techniques for
emissions calculations (e.g., emission factors) for the 2017 point
source emissions from State inventory databases.\9\
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\9\ Information on CAMPD is available on EPA's website at:
<a href="https://campd.epa.gov/">https://campd.epa.gov/</a>.
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For electric generating unit facilities in the 2015 ozone NAAQS
nonattainment areas, Wisconsin estimated ozone season day operations by
selecting the ozone season day with the 99th percentile highest heat
input for each unit. Ozone season day emissions for VOC and
NO<INF>X</INF> were calculated by multiplying average emission rates of
VOC and NO<INF>X</INF> for the 2017 ozone season by the maximum ozone
season day heat inputs. NO<INF>X</INF> emission rates were derived from
CAMPD, and VOC emission rates were derived by dividing annual VOC
emissions reported to the Wisconsin Air Emissions Inventory (AEI)
system by the 2017 annual heat input reported to the CAMPD database.
Wisconsin tabulated the 2017 emissions inventory for non-EGU point
sources using the emissions data reported annually by each facility
operator to the Wisconsin AEI. The AEI calculates emissions for each
individual emissions unit or process line by multiplying fuel or
process throughput by the appropriate emission factor that is derived
from mass balance analysis, stack testing, continuous emissions
monitoring, engineering analysis, or the EPA's WebFIRE database.\10\
Ozone season summer day emissions were calculated for each unit at a
facility by multiplying annual emissions by a factor representing the
amount of time the unit is in operation during the third quarter of the
calendar year, and summed each unit's emissions to determine total
ozone season summer day emissions for the facility.
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\10\ Information on WebFIRE is available on EPA's website at:
<a href="https://www.epa.gov/electronic-reporting-air-emissions/webfire">https://www.epa.gov/electronic-reporting-air-emissions/webfire</a>.
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Area Sources
Area sources, also called nonpoint sources, are sources that fall
below point source reporting levels or are too small or too numerous to
be identified individually. With the exception of agricultural silage,
selected categories of solvent utilization, and the Stage II refueling
category, Wisconsin based its 2017 area source emission inventory
estimates on the 2017 NEI.\11\ Agricultural silage and the selected
categories of solvent utilization emissions estimates were adjusted by
back calculations based on data from the 2020 NEI and the EPA's 2022
Emissions Modeling Platform Version 1. Stage II refueling emissions
were estimated using the EPA's Motor Vehicle Emissions Simulator model
(MOVES4.0.1) with the same inputs used for onroad modeling.\12\
Emission calculation methodologies used in developing the 2017 area
emissions inventory are available in the EPA's 2017 NEI Technical
Support Document.\13\ To represent area source emissions for the
partial counties, emissions from the entire county were allocated to
the partial county based on population data.
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\11\ Supporting documentation for the NEI is available on EPA's
website at <a href="https://www.epa.gov/air-emissions-inventories/2017-national-emissions-inventory-nei-data?adlt=strict">https://www.epa.gov/air-emissions-inventories/2017-national-emissions-inventory-nei-data?adlt=strict</a>.
\12\ Information on MOVES4.0.1 is available on EPA's website:
<a href="https://www.epa.gov/moves/moves-versions-limited-current-use">https://www.epa.gov/moves/moves-versions-limited-current-use</a>.
\13\ The 2017 NEI Technical Support Document is available on
EPA's website: <a href="https://www.epa.gov/sites/default/files/2020-04/documents/nei2017_tsd_full_30apr2020.pdf">https://www.epa.gov/sites/default/files/2020-04/documents/nei2017_tsd_full_30apr2020.pdf</a>.
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Onroad Mobile Sources
Onroad mobile sources are motor vehicles traveling on local
highways and roads. Examples of onroad mobile sources include cars,
trucks, buses, and road motorcycles. Onroad mobile source emissions
data for the Kenosha County and the Milwaukee areas were developed by
the Southeastern Wisconsin Regional Planning Commission (SEWRPC), the
Metropolitan Planning Organization for Southeast Wisconsin. The
Wisconsin Department of Transportation (WDOT) provided onroad mobile
source emissions data for Sheboygan County. Onroad emissions estimates
were developed using the EPA's MOVES4.0.1, which was the latest model
version at the time the inventory was developed. The modeling inputs to
MOVES include detailed transportation data (e.g., average speed
distributions and vehicle miles of travel by vehicle class, road type,
and hour of day).
Nonroad Mobile Sources
Nonroad mobile sources are motorized mobile equipment and other
engines that are primarily used off public roadways. For inventory
development, these can be divided into Commercial Marine, Aircraft and
Rail Locomotive (MAR) and all other nonroad categories such as
construction, agricultural, and industrial equipment. For non-MAR
sources, the 2017 nonroad emissions were developed using the nonroad
component of the EPA's MOVES4.0.1, using the same summer day
temperatures used for onroad modeling. The default MOVES monthly
distribution of agricultural activity was updated to a distribution
developed by the Lake Michigan Air Directors Consortium (LADCO),
consistent with what the EPA used for the 2017 and 2020 NEIs. The model
was run for the months of June, July, and August. Summer day emissions
were calculated by dividing the total emissions over these three months
by the number of days in the three months. For MAR sources, Wisconsin
used annual emission estimates for each area from the EPA's 2017 NEI,
and estimated summer day emissions by dividing the annual emissions by
365. Emissions for all nonroad sources were allocated from the full
county to the partial counties in the Milwaukee 2015 ozone NAAQS
nonattainment area based on surrogates such as population, land area,
and water area, depending on the category.
Summary of the Emissions Inventory
2017 ozone season day emissions of NO<INF>X</INF> and VOC for the
Wisconsin Moderate areas are shown in Table 1.
Table 1--Base Year 2017 Summer Day Emissions for Wisconsin Areas
[Tons/day (tpd)]
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Point EGU Point non-EGU Area Onroad Nonroad Total
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Kenosha County:
VOC................................................. 0.53 0.14 5.71 1.07 0.75 8.19
NOX................................................. 10.87 0.15 1.95 2.18 1.69 16.83
Milwaukee Area:
[[Page 16608]]
VOC................................................. 0.81 9.85 71.23 13.46 14.58 109.93
NOX................................................. 19.77 5.05 23.31 27.06 18.65 93.84
Sheboygan County:
VOC................................................. 0.35 0.16 4.73 0.65 0.66 6.55
NOX................................................. 5.97 0.08 1.25 1.64 1.11 10.05
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3. Evaluation of Wisconsin's 2017 Base Year Emissions Inventory
The EPA has reviewed Wisconsin's 2017 base year emissions inventory
for consistency with sections 172(c)(3) and 182(a)(1) of the CAA and
the EPA's emissions inventory requirements. The selection of 2017 as
the base year comports with the RFP baseline year requirements set
forth in the SIP Requirements Rule and codified at 40 CFR 51.1310(b).
The EPA has reviewed the techniques used by Wisconsin to derive the
emission estimates. Wisconsin documented the procedures used to
estimate the emissions for each of the major source types. The
documentation of the emission estimation procedures is thorough and
adequate to determine that Wisconsin followed acceptable procedures to
estimate the emissions. Therefore, the EPA is proposing to approve the
emissions inventories because they satisfy all Marginal and Moderate
requirements, in accordance with CAA sections 172(c)(3) and 182(a).
B. 15% RFP Plan
1. Background
The CAA requires that States with areas designated as nonattainment
for ozone achieve RFP toward attainment of the ozone NAAQS. CAA section
172(c)(2) contains a general requirement that nonattainment plans must
provide for emissions reductions that meet RFP. For areas classified
Moderate and above, section 182(b)(1) imposes a more specific RFP
requirement that a State is required to meet through a 15% reduction in
VOC emissions from the baseline anthropogenic emissions within six
years after November 15, 1990.
The SIP Requirements Rule addressed, among other things, RFP
requirements as they apply to areas designated nonattainment and
classified as Moderate for the 2015 ozone NAAQS.\14\ RFP requirements
under the 2015 ozone NAAQS are codified at 40 CFR 51.1310. The EPA
interprets the 15% VOC emission reduction requirement in CAA section
182(b)(1) such that a State that has already met the 15% requirement
for VOC for an area under either the 1-hour ozone NAAQS or a prior 8-
hour ozone NAAQS would not have to fulfill that requirement through
reductions of VOC again. Instead, the EPA interprets CAA section
172(c)(2) to require States with such areas to obtain 15% ozone
precursor emission reductions from VOC and/or NO<INF>X</INF> over the
first six years after the baseline year for the 2015 ozone NAAQS.
Wisconsin previously met the 15% VOC reduction requirement of CAA
section 182(b)(1) for the Kenosha County, Milwaukee, and Sheboygan
County areas under the 1-hour ozone NAAQS. Therefore, Wisconsin may
rely upon both VOC and NO<INF>X</INF> emissions reductions to meet the
RFP requirement for the 2015 ozone NAAQS.
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\14\ 83 FR 62998 at 63004, December 6, 2018.
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The SIP Requirements Rule specifies that the baseline emissions
inventory for RFP plans shall be the most recent calendar year prior to
the designation for which a complete triennial inventory is required to
be submitted to the EPA under the provisions of subpart A of 40 CFR
part 51, AERR, 40 CFR 51.1 through 50. For areas designated as
nonattainment in 2018, the most recent triennial inventory year
conducted for the NEI pursuant to the AERR rule is 2017. The rule also
allows the use of an alternative RFP baseline year that corresponds
with the year of the effective date of an area's designation, i.e.,
2018 for areas designated nonattainment in 2018.\15\
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\15\ 83 FR 62998 at 63005, December 6, 2018, codified at 40 CFR
51.1310(b).
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States may not take credit for VOC or NO<INF>X</INF> reductions
occurring from sources outside the nonattainment area for purposes of
meeting the 15% RFP requirements of CAA sections 172(c)(2), 182(b)(1),
and 182(c)(2)(B).\16\
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\16\ 40 CFR 51.1310(a)(6).
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Except as specifically provided in CAA section 182(b)(1)(C) and (D)
and CAA section 182(c)(2)(B), all emission reductions from SIP approved
or Federally promulgated measures that occur after the baseline
emissions inventory year are creditable for purposes of the RFP
requirements in this section, provided the reductions meet the
requirements for creditability, including the need to be enforceable,
permanent, quantifiable, and surplus.\17\ Further, the Administrator
has determined that the four categories of control measures listed in
CAA section 182(b)(1)(D) are no longer required to be calculated for
exclusion in RFP analyses because due to the passage of time the effect
of these exclusions would be de minimis.\18\
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\17\ 40 CFR 51.1310(a)(5).
\18\ 40 CFR 51.1310(a)(7).
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2. Wisconsin's 15% RFP Plan
Emissions Inventories
To demonstrate that the Kenosha County, Milwaukee, and Sheboygan
County nonattainment areas have achieved 15% RFP over the six-year
attainment planning period, Wisconsin is using a 2017 base year
inventory and a 2023 RFP inventory. The procedures Wisconsin used to
develop the 2017 base year inventory are discussed in section II.A.,
above. Procedures used to develop the 2023 RFP inventory are as
follows. Wisconsin followed the same methodology they used to calculate
2017 emissions by multiplying average emission rates of VOC and
NO<INF>X</INF> for the ozone season by the maximum ozone season day
heat inputs. Non-EGU point sources were based on 2023 reported
emissions to the Wisconsin AEI. Area source emissions for 2023 were
estimated by extrapolating emissions for 2017 and the EPA's 2022
Emissions Modeling Platform.\19\ Area source emissions for the partial
counties were scaled from the EPA's 2022 Emissions Modeling Platform
whole counties level using county population ratios. Onroad mobile
source emissions estimates for 2023 were developed using the EPA's
MOVES4.0.1. For non-MAR nonroad
[[Page 16609]]
mobile sources, the 2023 nonroad emissions were developed using the
nonroad component of the EPA's MOVES4.0.1, with the updated monthly
distribution of agricultural activity as was done for 2017. For MAR
sources, Wisconsin obtained 2022 emissions from the EPA's 2022
Emissions Modeling Platform, Version 1, and projected 2023 emissions
with a linear extrapolation from the 2017 emissions and the 2022
modeling platform emissions. If the 2022 emissions were less than the
2017 emissions, the 2023 emissions were set to the 2022 emissions to
avoid an underestimation. All 2023 nonroad emissions were allocated to
the partial counties based on the same adjustment factors utilized for
2017 base year emissions.
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\19\ Similar to the 2017 inventories, Stage II refueling
emissions were estimated using MOVES4.0.1 with the same inputs used
for onroad modeling.
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2023 ozone season day emissions of NO<INF>X</INF> and VOC for the
Milwaukee area are shown in Table 2.
Table 2--2023 Summer Day Emissions for Wisconsin Moderate Areas
[tpd]
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Point EGU Point non-EGU Area Onroad Nonroad Total
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Kenosha County:
VOC................................................. 0.00 0.25 5.14 0.89 0.67 6.95
NOX................................................. 0.00 0.09 1.82 1.22 1.49 4.62
Milwaukee Area:
VOC................................................. 0.74 8.14 59.51 10.77 12.99 92.16
NOX................................................. 20.11 4.97 19.31 14.80 14.21 73.41
Sheboygan County:
VOC................................................. 0.18 0.10 4.27 0.56 0.57 5.68
NOX................................................. 4.24 0.08 0.86 0.95 0.81 6.94
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15% RFP Demonstration
Wisconsin demonstrated that each Moderate area has achieved 15% RFP
over the six-year attainment planning period. Wisconsin has documented
Federal control measures and State measures adopted into the Wisconsin
SIP that are permanent and enforceable and can be used to achieve
emissions reductions.
Wisconsin has implemented NO<INF>X</INF> RACM, codified at Wis.
Adm. Code NR 428.04 and 428.05, and NO<INF>X</INF> RACT, codified at
Wis. Adm. Code NR 428.22, if emission units exceed the major source
threshold of 100 tons per year. Wisconsin noted in their submittal that
We Energies Pleasant Prairie power plant's boilers B20-B23 were
permanently shut down on or around April 10, 2018, and are included in
Wisconsin construction permit 18-RAB-050-ERC. Wisconsin has also
implemented VOC RACT and National Emission Standards for Hazardous Air
Pollutants (NESHAPs). VOC RACT for major stationary sources is codified
in Wis. Adm. Code NR 424.
The EPA mobile source regulations currently being implemented
across the country include passenger vehicle, SUV, and light-duty truck
emission and fuel standards; light-duty truck and medium-duty passenger
vehicle evaporative standards; heavy-duty highway compression engine
standards; heavy-duty spark ignition engine standards; motorcycle
emission standards; Mobile Source Air Toxics fuel formulation
standards; passenger vehicle standards; and portable container emission
standards. The MOVES model incorporates these Federal emissions control
programs into its projections. These emissions reductions measures are
permanent and enforceable and are implemented nationally, including in
Wisconsin's nonattainment areas.
Table 3 through Table 5 show the calculations used to determine
that emissions reductions in each Moderate nonattainment area are
sufficient to meet the 15% RFP requirement.
Table 3--Kenosha County 15% RFP Calculations
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Description Formula VOC (tpd) NOX (tpd)
----------------------------------------------------------------------------------------------------------------
A. 2017 base year inventory......... ........................ 8.19................... 16.83.
B. RFP reductions totaling 15% (VOC% ........................ 9%..................... 6%.
+ NOX% = 15%).
C. RFP emissions reductions required A*B..................... 0.74................... 1.01.
between 2017 & 2023.
D. RFP Target Level for 2023........ A-C..................... 7.45................... 15.82.
E. Creditable reductions between ........................ 0.79................... 12.03.
2017 and 2023.
F. Compare creditable reductions to E>C?.................... Yes.................... Yes.
RFP reduction requirements to
determine if at least 15% reduction
is achieved.
G. 2023 Projected Emissions......... ........................ 6.95................... 4.62.
H. Compare RFP target with 2023 G<D?.................... Yes.................... Yes.
projected emissions to determine if
RFP requirements are met.
----------------------------------------------------------------------------------------------------------------
Wisconsin assumed a 9% reduction in VOC and 6% reduction in
NO<INF>X</INF> from 2017-2023 to meet the 15% RFP requirement for the
Kenosha County area. Emissions reductions of 0.53 tpd VOC and 10.87 tpd
NO<INF>X</INF> can be attributed to permanent and enforceable control
measures in the EGU point source category. Emission reductions of 0.18
tpd VOC and 0.96 tpd NO<INF>X</INF> were calculated in the onroad
sector. Emission reductions of 0.08 tpd VOC and 0.20 tpd NO<INF>X</INF>
were calculated in the nonroad sector.
[[Page 16610]]
Table 4--Milwaukee Area 15% RFP Calculations
----------------------------------------------------------------------------------------------------------------
Description Formula VOC (tpd) NOX (tpd)
----------------------------------------------------------------------------------------------------------------
A. 2017 base year inventory......... ........................ 109.93................. 93.84.
B. RFP reductions totaling 15% (VOC% ........................ 3%..................... 12%.
+ NOX% = 15%).
C. RFP emissions reductions required A*B..................... 3.30................... 11.26.
between 2017 & 2023.
D. RFP Target Level for 2023........ A-C..................... 106.63................. 82.58.
E. Creditable reductions between ........................ 17.77.................. 20.43.
2017 and 2023.
F. Compare creditable reductions to E>C?.................... Yes.................... Yes.
RFP reduction requirements to
determine if at least 15% reduction
is achieved.
G. 2023 Projected Emissions......... ........................ 92.16.................. 73.41.
H. Compare RFP target with 2023 G<D?.................... Yes.................... Yes.
projected emissions to determine if
RFP requirements are met.
----------------------------------------------------------------------------------------------------------------
Wisconsin assumed a 3% reduction in VOC and 12% reduction in
NO<INF>X</INF> from 2017-2023 to meet the 15% RFP requirement for the
Milwaukee area. Emissions reductions of 1.78 tpd VOC can be attributed
to permanent and enforceable control measures in the point source
category. Emission reductions of 2.69 tpd VOC and 12.26 tpd
NO<INF>X</INF> were calculated in the onroad sector. Emission
reductions of 1.59 tpd VOC and 4.44 tpd NO<INF>X</INF> were calculated
in the nonroad sector.
Table 5--Sheboygan County 15% RFP Calculations
----------------------------------------------------------------------------------------------------------------
Description Formula VOC (tpd) NOX (tpd)
----------------------------------------------------------------------------------------------------------------
A. 2017 base year inventory......... ........................ 6.55................... 10.05.
B. RFP reductions totaling 15% (VOC% ........................ 3%..................... 12%.
+ NOX% = 15%).
C. RFP emissions reductions required A*B..................... 0.20................... 1.21.
between 2017 & 2023.
D. RFP Target Level for 2023........ A-C..................... 6.35................... 8.84.
E. Creditable reductions between ........................ 0.87................... 3.11.
2017 and 2023.
F. Compare creditable reductions to E>C?.................... Yes.................... Yes.
RFP reduction requirements to
determine if at least 15% reduction
is achieved.
G. 2023 Projected Emissions......... ........................ 5.68................... 6.94.
H. Compare RFP target with 2023 G<D?.................... Yes.................... Yes.
projected emissions to determine if
RFP requirements are met.
----------------------------------------------------------------------------------------------------------------
Wisconsin assumed a 3% reduction in VOC and 12% reduction in
NO<INF>X</INF> from 2017-2023 to meet the 15% RFP requirement for
Sheboygan County. Emissions reductions of 0.23 tpd VOC and 1.73 tpd
NO<INF>X</INF> can be attributed to permanent and enforceable control
measures in the point source category. Emission reductions of 0.09 tpd
VOC and 0.66 tpd NO<INF>X</INF> were calculated in the onroad sector.
Emission reductions of 0.09 tpd VOC and 0.30 tpd NO<INF>X</INF> were
calculated in the nonroad sector.
3. Evaluation of Wisconsin's Moderate 15% RFP Plans
The EPA has reviewed Wisconsin's 15% RFP plan for consistency with
sections 172(c)(2) and 182(b)(1) of the CAA and 40 CFR 51.1310. The
selection of 2017 as the base year comports with the RFP baseline year
requirements set forth in the SIP Requirements Rule and codified at 40
CFR 51.1310(b). The EPA has reviewed the techniques used by Wisconsin
to derive the 2017 and 2023 emission estimates. Wisconsin documented
the procedures used to estimate the emissions for each of the major
source types. The documentation of emission estimation procedures is
thorough and adequate to determine that Wisconsin followed acceptable
procedures to estimate the emissions. Wisconsin has demonstrated that
these emission reductions are permanent and enforceable and will result
in at least 15% RFP in the Moderate areas over the six-year attainment
planning period beginning with the 2017 base year. Thus, the EPA is
proposing to approve Wisconsin's 15% RFP plan for the Moderate areas
for the 2015 ozone NAAQS.
C. Motor Vehicle Emissions Budgets
1. Background
Under section 176(c) of the CAA, transportation plans, programs, or
projects that receive Federal funding or support, such as the
construction of new highways, must ``conform'' to (i.e., be consistent
with) the SIP before they receive Federal funding or approval.
Conformity to the SIP means that transportation activities will not
cause or contribute to any new air quality violations, increase the
frequency or severity of any existing air quality problems, or delay
timely attainment or any required interim emissions reductions or any
other milestones. Regulations at 40 CFR part 93 subpart A set forth the
EPA policy, criteria, and procedures for demonstrating and ensuring
conformity of transportation activities to a SIP.
Transportation conformity is a requirement for nonattainment and
maintenance areas, and both are defined in 40 CFR 93.101. The Budgets
in a State's SIP serve as a ceiling on emissions from an area's planned
transportation system (see definition of ``motor vehicle emissions
budget'' in 40 CFR 93.101 and how the term is used in 40 CFR 93.109 and
93.118).
2. VOC and NO<INF>X</INF> Budgets for the Wisconsin Areas
The RFP plans for the Kenosha County area, Milwaukee area, and the
Sheboygan County area each include VOC and NO<INF>X</INF> Budgets for
2023, the milestone year for RFP. The EPA invites the public to comment
on the adequacy of these Budgets as well as on its proposed approval of
the Budgets and on other actions the EPA is proposing in this action.
For the Kenosha County and the Milwaukee areas, Wisconsin worked
[[Page 16611]]
with SEWRPC to prepare emissions inventories used to set the Budgets
for the year 2023. For Sheboygan County, Wisconsin worked with WDOT to
prepare emissions inventories used to set the Budgets for the year
2023. These inventories were developed using MOVES4.0.1, the latest
approved motor vehicle emissions model at the time Wisconsin began to
prepare this part of the SIP submission, and up-to-date assumptions
about vehicle miles traveled (VMT), socioeconomic variables, fuels
used, weather inputs, and other planning assumptions. Wisconsin's 2023
Budgets for the Moderate areas are shown in Table 6. Wisconsin included
a 7.5% increase to the projected VMT for 2023 for the Kenosha County
and the Milwaukee areas and a 15% increase to the VMT for 2023 for
Sheboygan County. This approach is consistent with the total onroad
emissions presented in Table 2, above, which accommodates future
variations in local transportation planning parameters, VMT forecasts,
and onroad fleet characteristics.
Table 6--2023 Motor Vehicle Emissions Budgets for 2023 for the Wisconsin
Ozone Nonattainment Areas
------------------------------------------------------------------------
Emissions
Area Pollutant (tpd)
------------------------------------------------------------------------
Kenosha County.................... VOC................. 0.89
NOX................. 1.22
Milwaukee Area.................... VOC................. 10.77
NOX................. 14.80
Sheboygan County.................. VOC................. 0.56
NOX................. 0.95
------------------------------------------------------------------------
3. Evaluation of the VOC and NO<INF>X</INF> Budgets
The VOC and NO<INF>X</INF> Budgets for the Kenosha County, the
Milwaukee, and the Sheboygan County areas were developed as part of an
interagency consultation process which includes Federal, State, and
local agencies. The Budgets were clearly identified and precisely
quantified. Wisconsin has demonstrated that these areas can meet the
15% RFP requirement for the 2015 ozone NAAQS, and onroad emissions will
remain under RFP target levels in 2023. The EPA is thus proposing
approval of the 2023 VOC and NO<INF>X</INF> Budgets for use in
determining transportation conformity in the Kenosha County, the
Milwaukee, and the Sheboygan County areas under the 2015 ozone NAAQS.
When reviewing submitted SIPs containing Budgets, the EPA reviews
the Budgets for adequacy. Once the EPA affirmatively finds the
submitted Budgets are adequate for transportation conformity purposes,
those Budgets must be used by metropolitan and Federal agencies in
determining whether proposed transportation projects conform to the SIP
as required by section 176(c) of the CAA.
The EPA's substantive criteria for determining adequacy of Budgets
are set out in 40 CFR 93.118(e)(4). The process for determining
adequacy is found in 40 CFR 93.118(f) and consists of three basic
steps: public notification of a SIP submission, a public comment
period, and the EPA's adequacy finding. The regulations that allow the
EPA to begin an adequacy review through a notice of proposed rulemaking
in the Federal Register are found in 40 CFR 93.118(f)(2). This proposal
notifies the public that the EPA has received a SIP submission with
Budgets that the EPA will review for adequacy and begins the public
comment period on the adequacy of the budgets. Comments must be
submitted to the docket for this proposal by the close of the comment
period on this proposal.
D. Motor Vehicle I/M Program
1. Background
In accordance with CAA section 182(b)(4), the EPA's I/M rule, at 40
CFR 51 subpart S, requires certain urbanized ozone nonattainment areas
classified as Moderate to implement a Basic motor vehicle I/M program.
The goal of I/M programs is to identify and repair high-emitting
vehicles to improve air quality in areas that are not attaining the
NAAQS.\20\ The CAA generally requires I/M programs for areas across the
country that meet certain criteria, such as air quality status,
population, and/or geographic location. The CAA also directed the EPA
to establish minimum performance standards for Basic and Enhanced I/M
programs. States have flexibility to design their own programs if they
can show that their program is as effective as the model benchmark
program of the respective performance standard detailed in the I/M
rule.
---------------------------------------------------------------------------
\20\ For more information, see Overview of Vehicle Inspection
and Maintenance (I/M) Programs (EPA-420-F-21-067, October 2021) at
<a href="https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P1013CC0.pdf">https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P1013CC0.pdf</a>.
---------------------------------------------------------------------------
Kenosha County and the Milwaukee areas were required to adopt an
Enhanced I/M program under the 1-hour ozone NAAQS. The Sheboygan County
area was required to adopt a Basic I/M program under the 1-hour ozone
NAAQS. The EPA fully approved Wisconsin's I/M program on August 16,
2001 (66 FR 42949) and approved revisions to the program on September
19, 2013 (78 FR 57501).
2. Wisconsin's I/M Certification
Wisconsin's I/M program has been in operation since 1984. It was
originally implemented in accordance with the 1977 CAA Amendments and
operated in the six counties of Kenosha, Milwaukee, Ozaukee, Racine,
Washington and Waukesha. Sheboygan County was added to the program in
July 1993, resulting in a seven-county program area that has remained
to the present. Vehicles were originally tested by measuring tailpipe
emissions using a steady-state idle test. Tampering inspections were
added in 1989. The I/M program is jointly administered by Wisconsin and
WDOT.
The 1990 CAA Amendments set additional requirements for I/M
programs. For Moderate areas, a ``Basic'' program was required under
section 182(b)(4). For serious or worse areas, an ``Enhanced'' program
was required under section 182(c)(3). The EPA's requirements for Basic
and Enhanced I/M programs are found in 40 CFR part 51, subpart S.
Wisconsin's I/M program transitioned to an Enhanced program in
December 1995. The major enhancement involved adding new test
procedures to more effectively identify high-emitting vehicles. These
new test procedures included a transient emissions test in which
tailpipe emissions were measured while the vehicle was driven on a
dynamometer, a treadmill-type device. Improving repairs and public
convenience were also major focuses of the enhancement effort.
[[Page 16612]]
Since July of 2001, all model year (MY) 1996 and later cars and
light trucks have been inspected by scanning the vehicle's computerized
second-generation on-board diagnostic (OBD) system instead of measuring
tailpipe emissions. As of July 2008, the program dropped tailpipe
testing entirely and has inspected all vehicles by scanning the OBDII
system. This change was the result of statutory changes in the State's
2007-2009 biennial budget which exempted model years of vehicles not
federally required to be equipped with the OBDII technology (MY 1995
and earlier cars and light trucks and MY 2006 and earlier heavy
trucks). To help offset the emissions reductions lost from exempting
the pre-OBDII vehicles, the program increased the testable fleet for
MYs 2007 and later by adding gasoline-powered vehicles between 10,001
to 14,000 pounds GVWR and diesel-powered vehicles of all weights up to
14,000 pounds GVWR.
The EPA fully approved Wisconsin's Enhanced I/M program on August
16, 2001 (66 FR 42949), including the program's legal authority and
administrative requirements in the Wisconsin Statutes and Wisconsin
Administrative Code. On June 7, 2012, Wisconsin submitted a SIP
revision to the EPA covering all the changes to the program since the
EPA approved the program in 2001. This submittal included a
demonstration under section 110(l) of the CAA addressing lost emission
reductions associated with the program changes. The EPA approved this
SIP revision on September 19, 2013 (78 FR 57501). Wisconsin is
certifying that the existing SIP-approved I/M program meets the Basic
I/M program requirements of CAA section 182(b)(4) for the Kenosha
County and Milwaukee areas under the 2015 ozone NAAQS.
Consistent with the I/M regulations, a State with an existing I/M
program would need to conduct and submit a performance standard
modeling analysis as well as make any necessary program revisions as
part of their Moderate area SIP submission to ensure that their I/M
program is operating at or above the Basic I/M performance standard
level for the 2015 ozone NAAQS. When certifying that an existing I/M
program meets applicable I/M requirements for a new NAAQS, it is
necessary that the State ensures that an I/M program reflects the I/M
rule's required elements for a Basic or Enhanced I/M program and the
applicable classification for the new ozone NAAQS. If an I/M program
for a previous NAAQS contains the required elements for a new NAAQS
(e.g., such as onroad mobile source testing for an Enhanced I/M
program), then the State may determine through the performance standard
modeling analysis that an existing SIP-approved program would meet the
applicable performance standard for purposes of the 2015 ozone NAAQS
without modification.
Wisconsin submitted an I/M performance standard modeling analysis
demonstrating that Wisconsin's current motor vehicle I/M program meets
the level of the EPA's Enhanced performance standard for areas
designated and classified under the 8-hour ozone standard, as specified
in 40 CFR 51.351(i). Wisconsin conducted the modeling analysis using
the EPA's mobile source emissions model, MOVES5.0.0, which was the
latest model version at the time this analysis was started.\21\ This
modeling was conducted for analysis year 2025 in accordance with the
EPA's technical guidance: ``Performance Standard Modeling for New and
Existing Vehicle Inspection and Maintenance (I/M) Programs Using the
MOVES Mobile Source Emissions Model'', EPA-420-B-22-034, October 2022
\22\ (October 2022 Performance Standard Modeling Guidance). The
performance standard modeling analysis involves a comparison of
emission reductions from the EPA's model program specified in 40 CFR
51.351(i) and Wisconsin's actual program. The analysis shows that the
emission reductions from Wisconsin's actual I/M program meet the
emission reductions modeled for the benchmark program of the Enhanced
I/M performance standards.
---------------------------------------------------------------------------
\21\ Information on MOVES5.0.0 is available on EPA's website:
<a href="https://www.epa.gov/moves/latest-version-motor-vehicle-emission-simulator-moves">https://www.epa.gov/moves/latest-version-motor-vehicle-emission-simulator-moves</a>.
\22\ <a href="https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P1015S5C.pdf">https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P1015S5C.pdf</a>.
---------------------------------------------------------------------------
3. Evaluation of Wisconsin's I/M Certification
The EPA's October 2022 Performance Modeling Guidance outlines the
process that a State may need to demonstrate that an area's current
Enhanced I/M program satisfies the Basic I/M SIP requirement: ``[I]t is
reasonable to assume that if an I/M program meets the Enhanced
performance standard, then it would also meet the Basic performance
standard so long as the analysis years are appropriate for the two 8-
hour ozone standards in question.'' \23\ The guidance goes on to
identify the attainment date as the appropriate analysis year for areas
that have been reclassified.\24\
---------------------------------------------------------------------------
\23\ October 2022 Performance Standard Modeling Guidance, p. 10.
\24\ Ibid.
---------------------------------------------------------------------------
Wisconsin's Moderate attainment date is August 3, 2024. Since the
attainment date for the 2015 ozone NAAQS has passed, based on the EPA's
October 2022 Performance Modeling Guidance, Wisconsin chose 2025 as the
analysis year, which is within the calendar year of the demonstration's
submittal. Therefore, the analysis year of 2025 is appropriate and
consistent with the EPA's guidance.
To demonstrate that an I/M program meets the Enhanced performance
standard, the actual I/M program must achieve the same or lower
emissions levels of NOX and VOC as the Federal model Enhanced program
to within 0.02 grams per mile (gpm).
As shown in Table 7, the emission rates from the Milwaukee County,
Wisconsin I/M program meet the Enhanced performance standard of 40 CFR
51.351(i) to within 0.02 gpm. Since the regional characteristics
included in the modeling and fleet emission rates were similar across
the Milwaukee program area, the EPA guidance supports modeling a single
county in the area. The Illinois-Indiana-Wisconsin area includes only a
single Wisconsin county, Milwaukee County, so only that county would
need to be modeled. Wisconsin conducted the performance modeling
analysis using the most recent version of the EPA's mobile source
emissions model, MOVES5.0.0, in accordance with the EPA's October 2022
Performance Modeling Guidance. Therefore, since Wisconsin's current I/M
program meets the applicable I/M performance requirements in all areas
in which the program is implemented and also meets the Basic I/M
requirements of CAA section 182(b)(4), we are proposing to approve
Wisconsin's I/M program SIP element for the required subject Moderate
areas under the 2015 ozone NAAQS.
[[Page 16613]]
Table 7--Summary of Wisconsin's I/M Performance Standard Evaluation for the 2015 Moderate Ozone Nonattainment
Areas
----------------------------------------------------------------------------------------------------------------
I/M performance Does existing
Wisconsin I/M I/M performance standard program meet I/M
Pollutant program emission standard benchmark plus performance
rate (gpm) benchmark (gpm) 0.02 buffer (gpm) standard?
----------------------------------------------------------------------------------------------------------------
VOC................................. 0.2422 0.2362 0.2562 Yes.
NOX................................. 0.2217 0.2212 0.2412 Yes.
----------------------------------------------------------------------------------------------------------------
E. NNSR Review
1. Background
NNSR is a preconstruction review permit program that applies to new
major stationary sources or major modifications at existing sources
within a nonattainment area and is required under CAA sections
172(c)(5) and 173. NNSR permit program requirements were adopted for
the 2015 ozone NAAQS at 40 CFR 51.1314 as part of the 2015 SIP
Requirements Rule. The minimum SIP requirements for NNSR permitting
programs for the 2015 ozone NAAQS are contained in 40 CFR 51.165. The
SIP for each ozone nonattainment area must contain NNSR provisions
that: (1) set major source thresholds for NOX and VOC pursuant to 40
CFR 51.165(a)(1)(iv)(A)(1)(i)-through(iv) and (2); (2) classify
physical changes as a major source if the change would constitute a
major source by itself pursuant to 40 CFR 51.165(a)(1)(iv)(A)(3); (3)
consider any significant net emissions increase of NOX as a significant
net emissions increase for ozone pursuant to 40 CFR 51.165(a)(1)(v)(E);
(4) consider any increase of VOC emissions in Extreme ozone
nonattainment areas as a significant net emissions increase and a major
modification for ozone pursuant to 40 CFR 51.165(a)(1)(v)(F); (5) set
significant emissions rates for VOC and NOX as ozone precursors
pursuant to 40 CFR 51.165(a)(1)(x)(A)through(C) and (E); (6) contain
provisions for emissions reductions credits pursuant to 40 CFR
51.165(a)(3)(ii)(C)(1)through(2); (7) provide that the requirements
applicable to VOC also apply to NOX pursuant to 40 CFR 51.165(a)(8);
(8) set offset ratios for VOC and NOX pursuant to 40 CFR
51.165(a)(9)(ii)through(iv); and (9) require public participation
procedures compliant with 40 CFR 51.165(i).
2. Wisconsin's NNSR Certification
Wisconsin affirms that the existing NNSR program meets the NNSR
requirements of CAA section 182(a)(2)(C) and (b)(5) for the Moderate
areas under the 2015 ozone NAAQS. Wisconsin has a long-standing and
fully implemented NNSR program. This is addressed in Wis. Adm. Code
Chapter NR 408. The EPA approved Wisconsin's NNSR program on January
19, 2022 (87 FR 2719). The major source thresholds for VOC and NOX
established in Chapter NR 408.02(21) are consistent with the major
source threshold requirements established in the CAA based on ozone
nonattainment classifications. Specifically, Chapter NR
408.02(21)(a)(1) and NR 408.02(21)(b)(1) establish major source
thresholds of 100 tons per year for VOC and NOX, respectively, in
Marginal or Moderate ozone nonattainment areas. Further, the emission
offset ratios established in Chapter NR 408.06(4) are consistent with
the emission offset ratio requirements established in the CAA based on
ozone nonattainment classifications. Specifically, Chapter NR 408.06(4)
establishes an offset ratio of 1.15 to 1 for Moderate areas, as
required by CAA section 182(b)(5).
3. Evaluation of Wisconsin's NNSR Certification
The EPA has reviewed Wisconsin's approved NNSR rules and is
proposing to approve Wisconsin's certification submittal because the
current SIP-approved NNSR program satisfies all the NNSR program
requirements currently applicable to the Moderate areas for the 2015
ozone NAAQS.
III. What action is the EPA taking?
The EPA is proposing to approve revisions to Wisconsin's SIP
pursuant to section 110 and part D of the CAA and the EPA's
regulations, because Wisconsin's April 2, 2025, attainment plan
submissions satisfy the base year emissions inventory, the RFP
demonstration including associated motor vehicle emissions budgets, I/
M, and NNSR requirements of the CAA for the Kenosha County, Milwaukee,
and the Sheboygan County areas for the 2015 ozone NAAQS. The EPA is
also initiating the adequacy process for the 2023 Budgets for the
Kenosha County, Milwaukee, and the Sheboygan County areas included in
this SIP submission.
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 approve State choices,
provided that they meet the criteria of the CAA. Accordingly, this
action merely approves State law as meeting Federal requirements and
does not impose additional requirements beyond those imposed by State
law. For these reasons, this 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 subject to Executive Order 14192 (90 FR 9065,
February 6, 2025) because SIP actions are exempt from review 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 approves 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.
[[Page 16614]]
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 rulemaking 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, Nitrogen oxides, Ozone,
Reporting and recordkeeping requirements, Volatile organic compounds.
Dated: March 26, 2026.
Anne Vogel,
Regional Administrator, Region 5.
[FR Doc. 2026-06442 Filed 4-1-26; 8:45 am]
BILLING CODE 6560-50-P
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</html>Indexed from Federal Register on April 2, 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.