[Federal Register Volume 87, Number 29 (Friday, February 11, 2022)]
[Proposed Rules]
[Pages 7978-7991]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-02945]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R05-OAR-2021-0949; FRL-9532-01-R5]


Air Plan Approval; Ohio; Redesignation of the Ohio Portion of the 
Cincinnati, Ohio-Kentucky Area to Attainment of the 2015 Ozone Standard

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to find 
that the Cincinnati, Ohio-Kentucky area (Area) is attaining the 2015 8-
hour ozone National Ambient Air Quality Standard (NAAQS or standard) 
and to approve a request from the Ohio Environmental Protection Agency 
(OEPA) to redesignate the Ohio portion of the Area to attainment for 
the 2015 ozone NAAQS because the request meets the statutory 
requirements for redesignation under the Clean Air Act (CAA). The Area 
includes Butler, Clermont, Hamilton, and Warren Counties in Ohio and 
Boone, Campbell, and Kenton Counties in Kentucky. OEPA submitted this 
request on December 21, 2021. EPA is also proposing to approve, as a 
revision to the Ohio State Implementation Plan (SIP), the state's plan 
for maintaining the 2015 8-hour ozone standard through

[[Page 7979]]

2035 in the Area. Finally, EPA is proposing to approve the state's 2026 
and 2035 volatile organic compound (VOC) and oxides of nitrogen 
(NO<INF>X</INF>) Motor Vehicle Emission Budgets (MVEBs) for the Ohio 
portion of the Area.

DATES: Comments must be received on or before March 14, 2022.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R05-
OAR-2021-0949 at https://www.regulations.gov or via email to 
<a href="/cdn-cgi/l/email-protection#98f9eaeaf9b6ebf9eaf9f0d8fde8f9b6fff7ee"><span class="__cf_email__" data-cfemail="1f7e6d6d7e316c7e6d7e775f7a6f7e31787069">[email protected]</span></a>. For comments submitted at Regulations.gov, follow 
the online instructions for submitting comments. Once submitted, 
comments cannot be edited or removed from Regulations.gov. For either 
manner of submission, EPA may publish any comment received to its 
public docket. Do not submit electronically any information you 
consider to be Confidential Business Information (CBI) or other 
information whose disclosure is restricted by statute. Multimedia 
submissions (audio, video, etc.) must be accompanied by a written 
comment. The written comment is considered the official comment and 
should include discussion of all points you wish to make. EPA will 
generally not consider comments or comment contents located outside of 
the primary submission (i.e. on the web, cloud, or other file sharing 
system). For additional submission methods, please contact the person 
identified in the FOR FURTHER INFORMATION CONTACT section. For the full 
EPA public comment policy, information about CBI or multimedia 
submissions, and general guidance on making effective comments, please 
visit https://www2.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: Olivia Davidson, Environmental 
Scientist, Attainment Planning and Maintenance Section, Air Programs 
Branch (AR-18J), Environmental Protection Agency, Region 5, 77 West 
Jackson Boulevard, Chicago, Illinois 60604, (312) 886-0266, 
<a href="/cdn-cgi/l/email-protection#1b7f7a6d727f687475357477726d727a5b7e6b7a357c746d"><span class="__cf_email__" data-cfemail="fe9a9f88979a8d9190d091929788979fbe9b8e9fd0999188">[email protected]</span></a>. The EPA Region 5 office is open from 8:30 a.m. 
to 4:30 p.m., Monday through Friday, excluding Federal holidays and 
facility closures due to COVID-19.

SUPPLEMENTARY INFORMATION: Throughout this document whenever ``we,'' 
``us,'' or ``our'' is used, we mean EPA. This supplementary information 
section is arranged as follows:

I. What are the actions EPA is proposing?
II. What is the background for these actions?
III. What are the criteria for redesignation?
IV. What is EPA's analysis of Ohio's redesignation request?
    A. Has the area attained the 2015 8-hour ozone NAAQS?
    B. Has Ohio met all applicable requirements of section 110 and 
part D of the CAA for the Area, and does the Ohio portion of the 
area have a fully approved SIP under section 110(k) of the CAA?
    C. Are the air quality improvements in the Area due to permanent 
and enforceable emission reductions?
    D. Does Ohio have a fully approvable ozone maintenance plan for 
the Area?
V. Has the state adopted approvable motor vehicle emission budgets?
    A. Motor Vehicle Emission Budgets
    B. What is a safety margin?
VI. Proposed Actions
VII. Statutory and Executive Order Reviews

I. What are the actions EPA is proposing?

    EPA is proposing to take several related actions. EPA is proposing 
to determine that the Area, currently designated nonattainment, is 
attaining the 2015 ozone standard. This is based on quality-assured and 
certified monitoring data for 2019-2021 and EPA's findings that the 
Ohio portion of the Area has met the requirements for redesignation 
under section 107(d)(3)(E) of the CAA. EPA is thus proposing to approve 
OEPA's request to change the legal designation of the Ohio portion of 
the Area from nonattainment to attainment for the 2015 ozone standard. 
EPA is also proposing to approve, as a revision to the Ohio SIP, the 
state's maintenance plan (such approval being one of the CAA criteria 
for redesignation to attainment status) for the Area. The maintenance 
plan is designed to keep the Area in attainment of the 2015 ozone NAAQS 
through 2035. Finally, EPA is proposing to approve the newly 
established 2026 and 2035 MVEBs for the Ohio portion of the Area for 
transportation conformity purposes.

II. What is the background for these actions?

    EPA has determined that ground-level ozone is detrimental to human 
health. On October 1, 2015, EPA promulgated a revised 8-hour ozone 
NAAQS of 0.070 parts per million (ppm). See 80 FR 65291 (October 26, 
2015). Under EPA's regulations at 40 CFR part 50, the 2015 8-hour ozone 
NAAQS is attained in an area when the 3-year average of the annual 
fourth highest daily maximum 8-hour average concentration is equal to 
or less than 0.070 ppm, when truncated after the thousandth decimal 
place, at all of the ozone monitoring sites in the area. See 40 CFR 
50.15 and appendix P to 40 CFR part 50.
    Upon promulgation of a new or revised NAAQS, section 107(d)(1)(B) 
of the CAA requires EPA to designate as nonattainment any areas that 
are violating the NAAQS, based on the most recent three years of 
quality assured ozone monitoring data. The Cincinnati area was 
designated as a marginal nonattainment area for the 2015 ozone NAAQS on 
June 4, 2018 (83 FR 25776, effective August 3, 2018).

III. What are the criteria for redesignation?

    Section 107(d)(3)(E) of the CAA allows redesignation of an area to 
attainment of the NAAQS provided that: (1) The Administrator (EPA) 
determines that the area has attained the NAAQS; (2) the Administrator 
has fully approved the applicable implementation plan for the area 
under section 110(k) of the CAA; (3) the Administrator determines that 
the improvement in air quality is due to permanent and enforceable 
reductions in emissions resulting from implementation of the applicable 
SIP, applicable Federal air pollutant control regulations, and other 
permanent and enforceable emission reductions; (4) the Administrator 
has fully approved a maintenance plan for the area as meeting the 
requirements of section 175A of the CAA; and (5) the state containing 
the area has met all requirements applicable to the area for the 
purposes of redesignation under section 110 and part D of the CAA.
    On April 16, 1992, EPA provided guidance on redesignations in the 
General Preamble for the Implementation of Title I of the CAA 
Amendments of 1990 (57 FR 13498) and supplemented this guidance on 
April 28, 1992 (57 FR 18070). EPA has provided further guidance on 
processing redesignation requests in the following documents:

    1. ``Ozone and Carbon Monoxide Design Value Calculations,'' 
Memorandum from Bill Laxton. Director, Technical Support Division, 
June 18, 1990;
    2. ``Maintenance Plans for Redesignation of Ozone and Carbon 
Monoxide Nonattainment Areas,'' Memorandum from G.T. Helms, Chief, 
Ozone/Carbon Monoxide Programs Branch, April 30, 1992;
    3. ``Contingency Measures for Ozone and Carbon Monoxide (CO) 
Redesignations,'' Memorandum from G.T. Helms, Chief, Ozone/Carbon 
Monoxide Programs Branch, June 1, 1992;
    4. ``Procedures for Processing Requests to Redesignate Areas to 
Attainment,'' Memorandum from John Calcagni, Director, Air Quality 
Management Division, September 4, 1992 (the ``Calcagni 
Memorandum'');
    5. ``State Implementation Plan (SIP) Actions Submitted in 
Response to Clean Air Act (CAA) Deadlines,'' Memorandum from John 
Calcagni, Director, Air Quality Management Division, October 28, 
1992;
    6. ``Technical Support Documents (TSDs) for Redesignation of 
Ozone and Carbon

[[Page 7980]]

Monoxide (CO) Nonattainment Areas,'' Memorandum from G.T. Helms, 
Chief, Ozone/Carbon Monoxide Programs Branch, August 17, 1993;
    7. ``State Implementation Plan (SIP) Requirements for Areas 
Submitting Requests for Redesignation to Attainment of the Ozone and 
Carbon Monoxide (CO) National Ambient Air Quality Standards (NAAQS) 
On or After November 15, 1992,'' Memorandum from Michael H. Shapiro, 
Acting Assistant Administrator for Air and Radiation, September 17, 
1993;
    8. ``Use of Actual Emissions in Maintenance Demonstrations for 
Ozone and CO Nonattainment Areas,'' Memorandum from D. Kent Berry, 
Acting Director, Air Quality Management Division, November 30, 1993;
    9. ``Part D New Source Review (Part D NSR) Requirements for 
Areas Requesting Redesignation to Attainment,'' Memorandum from Mary 
D. Nichols, Assistant Administrator for Air and Radiation, October 
14, 1994; and
    10. ``Reasonable Further Progress, Attainment Demonstration, and 
Related Requirements for Ozone Nonattainment Areas Meeting the Ozone 
National Ambient Air Quality Standard,'' Memorandum from John S. 
Seitz, Director, Office of Air Quality Planning and Standards, May 
10, 1995.

IV. What is EPA's analysis of Ohio's redesignation request?

A. Has the area attained the 2015 8-hour ozone NAAQS?

    For redesignation of a nonattainment area to attainment, the CAA 
requires EPA to determine that the area has attained the applicable 
NAAQS (CAA section 107(d)(3)(E)(i)). An area is attaining the 2015 
ozone NAAQS if it meets the 2015 ozone NAAQS, as determined in 
accordance with 40 CFR 50.15 and appendix P of part 50, based on three 
complete, consecutive calendar years of quality-assured air quality 
data for all monitoring sites in the area. To attain the NAAQS, the 
three-year average of the annual fourth-highest daily maximum 8-hour 
average ozone concentrations (ozone design values) at each monitor must 
not exceed 0.070 ppm. The air quality data must be collected and 
quality-assured in accordance with 40 CFR part 58 and recorded in EPA's 
Air Quality System (AQS). Ambient air quality monitoring data for the 
3-year period must also meet data completeness requirements. An ozone 
design value is valid if daily maximum 8-hour average concentrations 
are available for at least 90 percent of the days within the ozone 
monitoring seasons,\1\ on average, for the three-year period, with a 
minimum data completeness of 75 percent during the ozone monitoring 
season of any year during the three-year period. See section 4 of 
appendix U to 40 CFR part 50.
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    \1\ The ozone season is defined by state in 40 CFR 58 appendix 
D. For the 2012-2014 and 2013-2015 time periods, the ozone seasons 
for Ohio, Indiana, and Kentucky were April-October, April-September, 
and March-October, respectively. Beginning in 2016, the ozone 
seasons for Ohio, Indiana and Kentucky are March-October. See, 80 FR 
65292, 65466-67 (October 26, 2015).
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    EPA has reviewed the available ozone monitoring data from 
monitoring sites in the Area for the 2019-2021 period. These data have 
been quality assured, are recorded in the AQS, and have been certified. 
These data demonstrate that the Area is attaining the 2015 ozone NAAQS. 
The annual fourth-highest 8-hour ozone concentrations and the 3-year 
average of these concentrations (monitoring site ozone design values) 
for each monitoring site are summarized in Table 1.

 Table 1--Annual 4th High Daily Maximum 8-Hour Ozone Concentrations and 3-Year Average of the 4th High Daily Maximum 8-Hour Ozone Concentrations for the
                                                                          Area
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                                                                                           2019 4th high   2020 4th high   2021 4th high     2019-2021
                  State                               County                  Monitor          (ppm)           (ppm)           (ppm)      average  (ppm)
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Ohio....................................  Butler........................     39-017-0018           0.067           0.070           0.064           0.067
                                                                             39-017-0023           0.067           0.067           0.066           0.066
                                                                             39-017-9991           0.065           0.064           0.063           0.064
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                                          Clermont......................     39-025-0022           0.071           0.064           0.065           0.066
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                                          Hamilton......................     39-061-0006           0.072           0.070           0.070           0.070
                                                                             39-061-0010           0.067           0.070           0.064           0.067
                                                                             39-061-0040           0.071           0.068           0.069           0.069
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                                          Warren........................     39-165-0007           0.070           0.071           0.069           0.070
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Kentucky................................  Boone.........................     21-015-0003           0.062           0.062           0.061           0.061
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                                          Campbell......................     21-037-3002           0.062           0.063           0.064           0.063
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    The 3-year ozone design value for 2019-2021 is 0.07 ppm,\2\ which 
meets the 2015 ozone NAAQS. Therefore, in today's action, EPA proposes 
to determine that the Area is attaining the 2015 ozone NAAQS.
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    \2\ The monitor ozone design value for the monitor with the 
highest 3-year averaged concentration.
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    EPA will not take final action to determine that the Area is 
attaining the NAAQS nor to approve the redesignation of this area if 
the design value of a monitoring site in the area exceeds the NAAQS 
after proposal but prior to final approval of the redesignation. As 
discussed in section IV.D.3. below, OEPA has committed to continue 
monitoring ozone in this area to verify maintenance of the 2015 ozone 
NAAQS.

B. Has Ohio met all applicable requirements of section 110 and part D 
of the CAA for the area, and does the Ohio portion of the area have a 
fully approved SIP under section 110(k) of the CAA?

    As criteria for redesignation of an area from nonattainment to 
attainment of a NAAQS, the CAA requires EPA to determine that the state 
has met all applicable requirements under section 110 and part D of 
title I of the CAA (see section 107(d)(3)(E)(v) of the CAA) and that 
the state has a fully approved SIP under section 110(k) of the CAA (see 
section 107(d)(3)(E)(ii) of the CAA). EPA proposes to find that Ohio 
has a fully approved SIP under section 110(k) of the CAA. Additionally, 
EPA proposes to find that the Ohio SIP satisfies the criterion that it 
meets applicable SIP requirements, for purposes of redesignation, under 
section 110 and

[[Page 7981]]

part D of title I of the CAA (requirements specific to nonattainment 
areas for the 2015 ozone NAAQS). In making these proposed 
determinations, EPA ascertained which CAA requirements are applicable 
to the Area and the Ohio SIP and, if applicable, whether the required 
Ohio SIP elements are fully approved under section 110(k) and part D of 
the CAA. As discussed more fully below, SIPs are required to be fully 
approved only with respect to currently applicable requirements of the 
CAA.
    The September 4, 1992, Calcagni memorandum (see ``Procedures for 
Processing Requests to Redesignate Areas to Attainment,'' Memorandum 
from John Calcagni, Director, Air Quality Management Division, 
September 4, 1992) describes EPA's interpretation of section 
107(d)(3)(E) of the CAA. Under this interpretation, a state and the 
area it wishes to redesignate must meet the relevant CAA requirements 
that are due prior to the state's submittal of a complete redesignation 
request for the area. See also the September 17, 1993, Michael Shapiro 
memorandum and 60 FR 12459, 12465-66 (March 7, 1995) (redesignation of 
Detroit-Ann Arbor, Michigan to attainment of the 1-hour ozone NAAQS). 
Applicable requirements of the CAA that come due subsequent to the 
state's submittal of a complete request remain applicable until a 
redesignation to attainment is approved but are not required as a 
prerequisite to redesignation. See section 175A(c) of the CAA. Sierra 
Club v. EPA, 375 F.3d 537 (7th Cir. 2004). See also 68 FR 25424, 25427 
(May 12, 2003) (redesignation of the St. Louis/East St. Louis area to 
attainment of the 1-hour ozone NAAQS).
1. Ohio Has Met All Applicable Requirements of Section 110 and Part D 
of the CAA Applicable to the Ohio Portion of the Area for Purposes of 
Redesignation
a. Section 110 General Requirements for Implementation Plans
    Section 110(a)(2) of the CAA delineates the general requirements 
for a SIP. Section 110(a)(2) provides that the SIP must have been 
adopted by the state after reasonable public notice and hearing, and 
that, among other things, it must: (1) Include enforceable emission 
limitations and other control measures, means or techniques necessary 
to meet the requirements of the CAA; (2) provide for establishment and 
operation of appropriate devices, methods, systems and procedures 
necessary to monitor ambient air quality; (3) provide for 
implementation of a source permit program to regulate the modification 
and construction of stationary sources within the areas covered by the 
plan; (4) include provisions for the implementation of part C 
prevention of significant deterioration (PSD) and part D new source 
review (NSR) permit programs; (5) include provisions for stationary 
source emission control measures, monitoring, and reporting; (6) 
include provisions for air quality modeling; and, (7) provide for 
public and local agency participation in planning and emission control 
rule development.
    Section 110(a)(2)(D) of the CAA requires SIPs to contain measures 
to prevent sources in a state from significantly contributing to air 
quality problems in another state. To implement this provision, EPA has 
required certain states to establish programs to address transport of 
certain air pollutants, e.g., NO<INF>X</INF> SIP call.\3\ However, like 
many of the 110(a)(2) requirements, the section 110(a)(2)(D) SIP 
requirements are not linked with a particular area's ozone designation 
and classification. EPA concludes that the SIP requirements linked with 
an area's ozone designation and classification are the relevant 
measures to evaluate when reviewing a redesignation request for the 
area. The section 110(a)(2)(D) requirements, where applicable, continue 
to apply to a state regardless of the designation of any one particular 
area within the state. Thus, we believe these requirements are not 
applicable requirements for purposes of redesignation. See 65 FR 37890 
(June 15, 2000), 66 FR 50399 (October 19, 2001), 68 FR 25418, 25426-27 
(May 13, 2003).
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    \3\ On October 27, 1992 (63 FR 57356), EPA issued a 
NO<INF>X</INF> SIP call requiring the District of Columbia and 22 
states to reduce emissions of NO<INF>X</INF> in order to reduce the 
transport of ozone and ozone precursors. In compliance with EPA's 
NO<INF>X</INF> SIP call, Ohio developed rules governing the control 
of NO<INF>X</INF> emissions from Electric Generating Units (EGUs), 
major non-EGU industrial boilers and turbines, and major cement 
kilns. EPA approved Ohio's rules as fulfilling Phase I of the 
NO<INF>X</INF> SIP Call on August 5, 2003 (68 FR 46089) and June 27, 
2005 (70 FR 36845), and as meeting Phase II of the NO<INF>X</INF> 
SIP Call on February 4, 2008 (73 FR 6427).
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    In addition, EPA believes that other section 110 elements that are 
neither connected with nonattainment plan submissions nor linked with 
an area's ozone attainment status are not applicable requirements for 
purposes of redesignation. The relevant area will still be subject to 
these requirements after the area is redesignated to attainment of the 
2015 ozone NAAQS. The section 110 and part D requirements which are 
linked with a particular area's designation and classification are the 
relevant measures to evaluate in reviewing a redesignation request. 
This approach is consistent with EPA's existing policy on applicability 
(i.e., for redesignations) of conformity and oxygenated fuels 
requirements, as well as with section 184 ozone transport requirements. 
See Reading, Pennsylvania proposed and final rulemakings, 61 FR 53174-
53176 (October 10, 1996) and 62 FR 24826 (May 7, 1997); Cleveland-
Akron-Loraine, Ohio final rulemaking, 61 FR 20458 (May 7, 1996); and 
Tampa, Florida final rulemaking, 60 FR 62748 (December 7, 1995). See 
also the discussion of this issue in the Cincinnati, Ohio ozone 
redesignation 65 FR 37890 (June 19, 2000), and the Pittsburgh, 
Pennsylvania ozone redesignation 66 FR 50399 (October 19, 2001).
    We have reviewed Ohio's SIP and have concluded that it meets the 
general SIP requirements under section 110 of the CAA, to the extent 
those requirements are applicable for purposes of redesignation. On 
August 11, 2021 (86 FR 43962), EPA approved elements of the SIP 
submitted by Ohio to meet the requirements of section 110 for the 2015 
ozone standard. The requirements of section 110(a)(2), however, are 
statewide requirements that are not linked to the 8-hour ozone 
nonattainment status of the Area. Therefore, EPA concludes that these 
infrastructure requirements are not applicable requirements for 
purposes of review of the state's 8-hour ozone redesignation request.
b. Part D Requirements.
    Section 172(c) of the CAA sets forth the basic requirements of air 
quality plans for states with nonattainment areas that are required to 
submit them pursuant to section 172(b). Subpart 2 of part D, which 
includes section 182 of the CAA, establishes specific requirements for 
ozone nonattainment areas depending on the areas' nonattainment 
classifications.
    The Area was classified as marginal under subpart 2 for the 2015 
ozone NAAQS. As such, the Area is subject to the subpart 1 requirements 
contained in section 172(c) and section 176. Similarly, the Area is 
subject to the subpart 2 requirements contained in section 182(a) 
(marginal nonattainment area requirements). A thorough discussion of 
the requirements contained in section 172(c) and 182 can be found in 
the General Preamble for Implementation of Title I (57 FR 13498).

[[Page 7982]]

i. Subpart 1 Section 172 Requirements
    As provided in subpart 2, for marginal ozone nonattainment areas 
such as the Area, the specific requirements of section 182(a) apply in 
lieu of the attainment planning requirements that would otherwise apply 
under section 172(c), including the attainment demonstration and 
reasonably available control measures (RACM) under section 172(c)(1), 
reasonable further progress (RFP) under section 172(c)(2), and 
contingency measures under section 172(c)(9). 42 U.S.C. 7511a(a).
    Section 172(c)(3) requires submission and approval of a 
comprehensive, accurate and current inventory of actual emissions. This 
requirement is superseded by the inventory requirement in section 
182(a)(1) discussed below.
    Section 172(c)(4) requires the identification and quantification of 
allowable emissions for major new and modified stationary sources in an 
area, and section 172(c)(5) requires source permits for the 
construction and operation of new and modified major stationary sources 
anywhere in the nonattainment area. EPA approved Ohio's NSR program on 
January 10, 2003 (68 FR 1366) and February 25, 2010 (75 FR 8496). 
Nonetheless, EPA has determined that, since PSD requirements will apply 
after redesignation, areas being redesignated need not comply with the 
requirement that a NSR program be approved prior to redesignation, 
provided that the area demonstrates maintenance of the NAAQS without 
part D NSR. A more detailed rationale for this view is described in a 
memorandum from Mary Nichols, Assistant Administrator for Air and 
Radiation, dated October 14, 1994, entitled, ``Part D New Source Review 
Requirements for Areas Requesting Redesignation to Attainment.'' Ohio 
has demonstrated that the Area will be able to maintain the standard 
without part D NSR in effect; therefore, EPA concludes that the state 
need not have a fully approved part D NSR program prior to approval of 
the redesignation request. See rulemakings for Detroit, Michigan (60 FR 
12467-12468, March 7, 1995); Cleveland-Akron-Lorain, Ohio (61 FR 20458, 
20469-20470, May 7, 1996); Louisville, Kentucky (66 FR 53665, October 
23, 2001); and Grand Rapids, Michigan (61 FR 31834-31837, June 21, 
1996). Ohio's PSD program will become effective in the Area upon 
redesignation to attainment. EPA approved Ohio's PSD program on January 
22, 2003 (68 FR 2909) and February 25, 2010 (75 FR 8496).
    Section 172(c)(6) requires the SIP to contain control measures 
necessary to provide for attainment of the NAAQS. Because attainment 
has been reached, no additional measures are needed to provide for 
attainment.
    Section 172(c)(7) requires the SIP to meet the applicable 
provisions of section 110(a)(2). As noted above, we believe the Ohio 
SIP meets the requirements of section 110(a)(2) for purposes of 
redesignation.
ii. Section 176 Conformity Requirements
    Section 176(c) of the CAA requires states to establish criteria and 
procedures to ensure that Federally supported or funded projects 
conform to the air quality planning goals in the applicable SIP. The 
requirement to determine conformity applies to transportation plans, 
programs and projects that are developed, funded or approved under 
title 23 of the United States Code (U.S.C.) and the Federal Transit Act 
(transportation conformity) as well as to all other Federally supported 
or funded projects (general conformity). State transportation 
conformity SIP revisions must be consistent with Federal conformity 
regulations relating to consultation, enforcement and enforceability 
that EPA promulgated pursuant to its authority under the CAA.
    EPA interprets the conformity SIP requirements \4\ as not applying 
for purposes of evaluating a redesignation request under section 107(d) 
because state conformity rules are still required after redesignation 
and Federal conformity rules apply where state conformity rules have 
not been approved. See Wall v. EPA, 265 F.3d 426 (6th Cir. 2001) 
(upholding this interpretation); see also 60 FR 62748 (December 7, 
1995) (redesignation of Tampa, Florida). Nonetheless, Ohio has an 
approved conformity SIP for the Area. See 80 FR 11133 (March 2, 2015).
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    \4\ CAA section 176(c)(4)(E) requires states to submit revisions 
to their SIPs to reflect certain Federal criteria and procedures for 
determining transportation conformity. Transportation conformity 
SIPs are different from SIPs requiring the development of Motor 
Vehicle Emission Budgets (MVEBs), such as control strategy SIPs and 
maintenance plans.
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iii. Section 182(a) Requirements
    Section 182(a)(1) requires states to submit a comprehensive, 
accurate, and current inventory of actual emissions from sources of VOC 
and NO<INF>X</INF> emitted within the boundaries of the ozone 
nonattainment area. OEPA submitted a 2014 base year emissions inventory 
for the Area on July 24, 2020. EPA approved this emissions inventory as 
a revision to the Ohio SIP on March 3, 2021 (86 FR 12270).
    Under section 182(a)(2)(A), states with ozone nonattainment areas 
that were designated prior to the enactment of the 1990 CAA amendments 
were required to submit, within six months of classification, all rules 
and corrections to existing VOC reasonably available control technology 
(RACT) rules that were required under section 172(b)(3) prior to the 
1990 CAA amendments. The Area is not subject to the section 182(a)(2) 
RACT ``fix up'' requirement for the 2015 ozone NAAQS because it was 
designated as nonattainment for this standard after the enactment of 
the 1990 CAA amendments and because Ohio complied with this requirement 
for the Area under the prior 1-hour ozone NAAQS. See 59 FR 23796 (May 
9, 1994) and 60 FR 15235 (March 23, 1995).
    Section 182(a)(2)(B) requires each state with a marginal ozone 
nonattainment area that implemented or was required to implement a 
vehicle inspection and maintenance (I/M) program prior to the 1990 CAA 
amendments to submit a SIP revision for an I/M program no less 
stringent than that required prior to the 1990 CAA amendments or 
already in the SIP at the time of the CAA amendments, whichever is more 
stringent. For the purposes of the 2015 ozone standard and the 
consideration of Ohio's redesignation request for this standard, the 
Area is not subject to the section 182(a)(2)(B) requirement because the 
Area was designated as nonattainment for the 2015 ozone standard after 
the enactment of the 1990 CAA amendments.
    Regarding the source permitting and offset requirements of section 
182(a)(2)(C) and section 182(a)(4), Ohio currently has a fully approved 
part D NSR program in place. EPA approved Ohio's PSD program on January 
22, 2003 (68 FR 2909) and February 25, 2010 (75 FR 8496). As discussed 
above, Ohio has demonstrated that the Area will be able to maintain the 
standard without part D NSR in effect; therefore, EPA concludes that 
the state need not have a fully approved part D NSR program prior to 
approval of the redesignation request. The state's PSD program will 
become effective in the Area upon redesignation to attainment.
    Section 182(a)(3) requires states to submit periodic emission 
inventories and a revision to the SIP to require the owners or 
operators of stationary sources to annually submit emission statements 
documenting actual VOC and NO<INF>X</INF> emissions. As discussed below 
in section IV.D.4. of this proposed rule,

[[Page 7983]]

Ohio will continue to update its emissions inventory at least once 
every three years. With regard to stationary source emission 
statements, EPA approved Ohio's emission statement rule on September 
27, 2007 (72 FR 54844). On July 24, 2020, Ohio certified that this 
approved SIP regulation remains in place and remains enforceable for 
the 2015 ozone standard. EPA approved Ohio's certification on March 3, 
2021 (81 FR 12270).
    The Ohio portion of the Area has satisfied all applicable 
requirements for purposes of redesignation under section 110 and part D 
of title I of the CAA.
2. The Ohio Portion of the Area Has a Fully Approved SIP for Purposes 
of Redesignation Under Section 110(k) of the CAA
    Ohio has adopted and submitted and EPA has approved at various 
times, provisions addressing the various SIP elements applicable for 
the ozone NAAQS. As discussed above, EPA has fully approved the Ohio 
SIP for the Area under section 110(k) for all requirements applicable 
for purposes of redesignation under the 2015 ozone NAAQS. EPA may rely 
on prior SIP approvals in approving a redesignation request (see the 
Calcagni memorandum at page 3; Southwestern Pennsylvania Growth 
Alliance v. Browner, 144 F.3d 984, 989-990 (6th Cir. 1998); Wall v. 
EPA, 265 F.3d 426), plus any additional measures it may approve in 
conjunction with a redesignation action (see 68 FR 25426 (May 12, 2003) 
and citations therein).

C. Are the air quality improvements in the Area due to permanent and 
enforceable emission reductions?

    To redesignate an area from nonattainment to attainment, section 
107(d)(3)(E)(iii) of the CAA requires EPA to determine that the air 
quality improvement in the area is due to permanent and enforceable 
reductions in emissions resulting from the implementation of the SIP 
and applicable Federal air pollution control regulations and other 
permanent and other permanent and enforceable emission reductions. EPA 
has determined that Ohio has demonstrated that that the observed ozone 
air quality improvement in the Area is due to permanent and enforceable 
reductions in VOC and NO<INF>X</INF> emissions resulting from state 
measures adopted into the SIP and Federal measures.
    In making this demonstration, the state has calculated the change 
in emissions between 2014 and 2019. The reduction in emissions and the 
corresponding improvement in air quality over this time period can be 
attributed to a number of regulatory control measures that the Area and 
upwind areas have implemented in recent years. In addition, OEPA 
provided an analysis to demonstrate the improvement in air quality was 
not due to unusually favorable meteorology. Based on the information 
summarized below, Ohio has adequately demonstrated that the improvement 
in air quality is due to permanent and enforceable emissions 
reductions.
1. Permanent and Enforceable Emission Controls Implemented
a. Regional NO<INF>X</INF> Controls
    Clean Air Interstate Rule (CAIR)/Cross State Air Pollution Rule 
(CSAPR). CAIR created regional cap-and-trade programs to reduce sulfur 
dioxide (SO<INF>2</INF>) and NO<INF>X</INF> emissions in 27 eastern 
states, including Ohio, that contributed to downwind nonattainment and 
maintenance of the 1997 8-hour ozone NAAQS and the 1997 fine 
particulate matter (PM<INF>2.5</INF>) NAAQS. See 70 FR 25162 (May 12, 
2005). EPA approved Ohio's CAIR regulations into the Ohio SIP on 
February 1, 2008 (73 FR 6034), and September 25, 2009 (74 FR 48857). In 
2008, the United States Court of Appeals for the District of Columbia 
Circuit (D.C. Circuit) initially vacated CAIR, North Carolina v. EPA, 
531 F.3d 896 (D.C. Cir. 2008), but ultimately remanded the rule to EPA 
without vacatur to preserve the environmental benefits provided by 
CAIR, North Carolina v. EPA, 550 F.3d 1176, 1178 (D.C. Cir. 2008). On 
August 8, 2011 (76 FR 48208), acting on the D.C. Circuit's remand, EPA 
promulgated CSAPR to replace CAIR and thus to address the interstate 
transport of emissions contributing to nonattainment and interfering 
with maintenance of the two air quality standards covered by CAIR as 
well as the 2006 PM<INF>2.5</INF> NAAQS. CSAPR requires substantial 
reductions of SO<INF>2</INF> and NO<INF>X</INF> emissions from electric 
generating units (EGUs) in 28 states in the Eastern United States.
    The D.C. Circuit's initial vacatur of CSAPR \5\ was reversed by the 
United States Supreme Court on April 29, 2014, and the case was 
remanded to the D.C. Circuit to resolve remaining issues in accordance 
with the high court's ruling. EPA v. EME Homer City Generation, L.P., 
134 S. Ct. 1584 (2014). On remand, the D.C. Circuit affirmed CSAPR in 
most respects, but invalidated without vacating some of the CSAPR 
budgets as to a number of states. EME Homer City Generation, L.P. v. 
EPA, 795 F.3d 118 (D.C. Cir. 2015). The remanded budgets include the 
Phase 2 NO<INF>X</INF> ozone season emissions budgets for Ohio. On 
September 7, 2016, in response to the remand, EPA finalized an update 
to CSAPR requiring further reductions in NO<INF>X</INF> emissions from 
EGUs beginning in May 2017. This final rule was projected to result in 
a 20% reduction in ozone season NO<INF>X</INF> emissions from EGUs in 
the eastern United States, a reduction of 800,000 tons in 2017 compared 
to 2015 levels.
---------------------------------------------------------------------------

    \5\ EME Homer City Generation, L.P. v. EPA, 696 F.3d 7, 38 (D.C. 
Cir. 2012).
---------------------------------------------------------------------------

    The improvement in ozone air quality in the Area from 2014 (a year 
when the design value for the area was above the NAAQS) to 2019 is 
partially due to CSAPR emissions reductions.
b. Federal Emission Control Measures
    A large portion of reductions in emissions in the Ohio portion of 
the Area from 2014-2019 were due to permanent and enforceable 
reductions in mobile source VOC and NO<INF>X</INF> emissions.
    From 2014 to 2019, onroad and nonroad mobile source emission 
reductions accounted for 63 percent of the total NO<INF>X</INF> 
reductions and 69 percent of the total VOC reductions in the Ohio 
portion of the Area. As laid out in the State's maintenance 
demonstration, NO<INF>X</INF> and VOC emissions in the Ohio portion of 
the area are projected to continue their downward trend throughout the 
maintenance period, driven primarily by point source emission 
reductions from source retirements for NO<INF>X</INF> and onroad and 
nonroad mobile source reductions for VOC. From 2019 to 2035, Ohio 
projected that 67 percent of the NO<INF>X</INF> emission reductions 
would be due to point source emission reductions and 95 percent of the 
VOC reductions in the Ohio portion of the area would be due to mobile 
source measures based on EPA-approved mobile source modeling.
    Reductions in VOC and NO<INF>X</INF> emissions have occurred 
statewide and in upwind areas as a result of Federal emission control 
measures, with additional emission reductions expected to occur in the 
future. Federal emission control measures include the following.
    Tier 2 Emission Standards for Vehicles and Gasoline Sulfur 
Standards. On February 10, 2000 (65 FR 6698), EPA promulgated Tier 2 
motor vehicle emission standards and gasoline sulfur control 
requirements. These emission control requirements result in lower VOC 
and NO<INF>X</INF> emissions from new cars and light duty trucks, 
including sport utility vehicles. With respect to fuels, this rule 
required refiners and importers of gasoline to meet lower standards for 
sulfur in gasoline, which were phased

[[Page 7984]]

in between 2004 and 2006. By 2006, refiners were required to meet a 30 
ppm average sulfur level, with a maximum cap of 80 ppm. This reduction 
in fuel sulfur content ensures the effectiveness of low emission-
control technologies. The Tier 2 tailpipe standards established in this 
rule were phased in for new vehicles between 2004 and 2009. EPA 
estimates that, when fully implemented, this rule will cut 
NO<INF>X</INF> and VOC emissions from light-duty vehicles and light-
duty trucks by approximately 76 and 28 percent, respectively. 
NO<INF>X</INF> and VOC reductions from medium-duty passenger vehicles 
included as part of the Tier 2 vehicle program are estimated to be 
approximately 37,000 and 9,500 tons per year, respectively, when fully 
implemented. In addition, EPA estimates that beginning in 2007, a 
reduction of 30,000 tons per year of NO<INF>X</INF> will result from 
the benefits of sulfur control on heavy-duty gasoline vehicles. Some of 
these emission reductions occurred by the attainment years and 
additional emission reductions will occur throughout the maintenance 
period, as older vehicles are replaced with newer, compliant model 
years.
    Tier 3 Emission Standards for Vehicles and Gasoline Sulfur 
Standards. On April 28, 2014 (79 FR 23414), EPA promulgated Tier 3 
motor vehicle emission and fuel standards to reduces both tailpipe and 
evaporative emissions and to further reduce the sulfur content in 
fuels. The rule will be phased in between 2017 and 2025. Tier 3 sets 
new tailpipe standards for the sum of VOC and NO<INF>X</INF> and for 
particulate matter. The VOC and NO<INF>X</INF> tailpipe standards for 
light-duty vehicles represent approximately an 80% reduction from 
today's fleet average and a 70% reduction in per-vehicle particulate 
matter (PM) standards. Heavy-duty tailpipe standards represent about a 
60% reduction in both fleet average VOC and NO<INF>X</INF> and per-
vehicle PM standards. The evaporative emissions requirements in the 
rule will result in approximately a 50 percent reduction from current 
standards and apply to all light-duty and onroad gasoline-powered 
heavy-duty vehicles. Finally, the rule lowers the sulfur content of 
gasoline to an annual average of 10 ppm by January 2017. As projected 
by these estimates and demonstrated in the onroad emission modeling for 
the Area, some of these emission reductions occurred by the attainment 
years and additional emission reductions will occur throughout the 
maintenance period, as older vehicles are replaced with newer, 
compliant model years.
    Heavy-Duty Diesel Engine Rules. In July 2000, EPA issued a rule for 
on-highway heavy-duty diesel engines that includes standards limiting 
the sulfur content of diesel fuel. Emissions standards for 
NO<INF>X</INF>, VOC and PM were phased in between model years 2007 and 
2010. In addition, the rule reduced the highway diesel fuel sulfur 
content to 15 parts per million by 2007, leading to additional 
reductions in combustion NO<INF>X</INF> and VOC emissions. EPA has 
estimated future year emission reductions due to implementation of this 
rule. Nationally, EPA estimated that 2015 NO<INF>X</INF> and VOC 
emissions would decrease by 1,260,000 tons and 54,000 tons, 
respectively. Nationally, EPA estimated that 2030 NO<INF>X</INF> and 
VOC emissions will decrease by 2,570,000 tons and 115,000 tons, 
respectively. As projected by these estimates and demonstrated in the 
on-road emission modeling for the Area, some of these emission 
reductions occurred by the attainment years and additional emission 
reductions will occur throughout the maintenance period, as older 
vehicles are replaced with newer, compliant model years.
    Nonroad Diesel Rule. On June 29, 2004 (69 FR 38958), EPA issued a 
rule adopting emissions standards for nonroad diesel engines and sulfur 
reductions in nonroad diesel fuel. This rule applies to diesel engines 
used primarily in construction, agricultural, and industrial 
applications. Emission standards are phased in for 2008 through 2015 
model years based on engine size. The SO<INF>2</INF> limits for nonroad 
diesel fuels were phased in from 2007 through 2012. EPA estimates that 
when fully implemented, compliance with this rule will cut 
NO<INF>X</INF> emissions from these nonroad diesel engines by 
approximately 90 percent. Some of these emission reductions occurred by 
the attainment years and additional emission reductions will occur 
throughout the maintenance period.
    Nonroad Spark-Ignition Engines and Recreational Engine Standards. 
On November 8, 2002 (67 FR 68242), EPA adopted emission standards for 
large spark-ignition engines such as those used in forklifts and 
airport ground-service equipment; recreational vehicles such as off-
highway motorcycles, all-terrain vehicles, and snowmobiles; and 
recreational marine diesel engines. These emission standards are phased 
in from model year 2004 through 2012. When fully implemented, EPA 
estimates an overall 72 percent reduction in VOC emissions from these 
engines and an 80 percent reduction in NO<INF>X</INF> emissions. Some 
of these emission reductions occurred by the attainment years and 
additional emission reductions will occur throughout the maintenance 
period.
    Category 3 Marine Diesel Engine Standards. On April 30, 2010 (75 FR 
22896) EPA issued emission standards for marine compression-ignition 
engines at or above 30 liters per cylinder. Tier 2 emission standards 
apply beginning in 2011, and are expected to result in a 15 to 25 
percent reduction in NO<INF>X</INF> emissions from these engines. Final 
Tier 3 emission standards apply beginning in 2016 and are expected to 
result in approximately an 80 percent reduction in NO<INF>X</INF> from 
these engines. Some of these emission reductions occurred by the 
attainment years and additional emission reductions will occur 
throughout the maintenance period.
c. Control Measures Specific to the Area
    Changes at several EGUs have resulted in reductions in 
NO<INF>X</INF> emissions. The Walter C. Beckjord facility in Clermont 
County, Ohio permanently shut down in October of 2014. NO<INF>X</INF> 
emissions from EGUs in Clermont County dropped from 44.88 Tons per 
summer day (TPSD) in 2014 to 15.87 TPSD in 2019, partly attributable to 
closure of the Walter C. Beckjord facility. Further, the DTE St. 
Bernard facility converted to natural gas from coal-fired boilers in 
November of 2015. NO<INF>X</INF> emissions from EGUs in Hamilton County 
dropped from 4.10 TPSD in 2014 to 2.40 TPSD in 2019, partially 
attributable to the DTE St. Bernard facility fuel conversion.
2. Emission Reductions
    Ohio is using a 2014 emissions inventory as the nonattainment year. 
This is appropriate because it was one of the years used to designate 
the area as nonattainment. Ohio is using a 2019 inventory as the 
attainment year inventory for the purposes of comparison, which is 
appropriate because it is one of the years in the 2019-2021 period used 
to demonstrate attainment. Area (including airports and railyards), 
nonroad mobile, and point source emissions (EGUs and non-EGUs) were 
collected from data available on EPA's Air Emissions Modeling 
website.\6\ Using Emissions Modeling platforms 2014v7.1 and 2016v2, 
OEPA collected data for the 2014 National Emissions Inventory (NEI) 
year and the 2016 NEI for the 2023, 2026 and 2032 projected emissions, 
versions 2014fd, 2016fj,

[[Page 7985]]

2023fj, 2026fj and 2032fd respectively. OEPA determined the 2016v2 
inventory was the appropriate inventory for the projected emission data 
as it represents the best available emission data, updated with EGU 
impacts of the CSAPR Update and improvements in methodologies related 
to solvents. TPSD emissions were then derived by dividing July 
emissions by the number of days in July. 2014 emissions were derived 
from the 2014v7.1 platform without modification. 2019 emissions were 
derived by interpolating between the 2016 and projected 2026 emissions 
from the 2016v2 (versions 2016fd and 2023fd) platform.
---------------------------------------------------------------------------

    \6\ https://www.epa.gov/air-emissions-modeling/2014-2016-version-7-air-emissions-modeling-platforms.
---------------------------------------------------------------------------

    OEPA compiled 2014 and 2019 actual point source emissions from 
state inventory databases. TPSD emissions were then derived by applying 
a conversion factor to the annual emissions. The conversion factor was 
derived from the emissions modeling platform 2016v2 as the ratio of the 
average July day to annual emissions for the non-EGU sector.
    Onroad mobile source emissions were developed in conjunction with 
the Ohio-Kentucky-Indiana Regional Council of Governments (OKI) and 
were calculated from emission factors produced by EPA's 2020 Motor 
Vehicle Emission Simulator (MOVES3) model and data extracted from the 
region's travel-demand model.
    Using the inventories described above, Ohio's submittal documents 
changes in VOC and NO<INF>X</INF> emissions from 2014 to 2019 for the 
Area. Emissions data are shown in Tables 2 through 7.

                             Table 2--Area NOX Emissions for Nonattainment Year 2014
                                                     [TPSD]
----------------------------------------------------------------------------------------------------------------
             County                    Point          Nonroad          Area           Onroad           Total
----------------------------------------------------------------------------------------------------------------
Ohio:
    Butler......................           11.06            4.21            2.46           12.40           30.13
    Clermont....................           44.91            2.33            1.14            6.90           55.28
    Hamilton....................           23.13            8.19            7.70           32.60           71.62
    Warren......................            0.94            3.21            1.03           11.00           16.18
Kentucky:
    Boone.......................           12.96            1.61            3.65            7.10           25.32
    Campbell....................            0.28            0.60            1.65            2.50            5.03
    Kenton......................            0.28            1.19            1.48            5.90            8.85
                                 -------------------------------------------------------------------------------
        Ohio Totals.............           80.04           17.94           12.33           62.90          173.21
                                 -------------------------------------------------------------------------------
        Area Totals.............           93.56           21.34           19.11           78.40          212.41
----------------------------------------------------------------------------------------------------------------


                             Table 3--Area VOC Emissions for Nonattainment Year 2014
                                                     [TPSD]
----------------------------------------------------------------------------------------------------------------
             County                    Point          Nonroad          Area           Onroad           Total
----------------------------------------------------------------------------------------------------------------
Ohio:
    Butler......................            2.93            3.26           13.38            6.10           25.67
    Clermont....................            0.67            2.51            6.26            3.50           12.94
    Hamilton....................            2.76            8.39           31.81           13.70           56.66
    Warren......................            0.51            2.89            8.91            3.70           16.01
Kentucky:
    Boone.......................            1.95            2.70            9.28            1.60           15.53
    Campbell....................            0.49            0.68            2.48            0.90            4.55
    Kenton......................            0.46            0.98            4.03            1.60            7.07
                                 -------------------------------------------------------------------------------
        Ohio Totals.............            6.87           17.05           60.36           27.00          111.28
                                 -------------------------------------------------------------------------------
        Area Totals.............            9.77           21.41           76.15           31.10          138.43
----------------------------------------------------------------------------------------------------------------


                              Table 4--Area NOX Emissions for Attainment Year 2019
                                                     [TPSD]
----------------------------------------------------------------------------------------------------------------
             County                    Point          Nonroad          Area           Onroad           Total
----------------------------------------------------------------------------------------------------------------
Ohio:
    Butler......................            8.63            2.01            2.26            7.00           19.90
    Clermont....................           15.87            1.43            1.09            3.80           22.19
    Hamilton....................           36.16            5.90            5.34           18.00           65.40
    Warren......................            2.08            2.01            1.04            6.20           11.33
Kentucky:
    Boone.......................            5.99            0.74            2.54            4.70           13.97
    Campbell....................            0.29            0.38            0.92            2.20            3.79
    Kenton......................            0.28            0.57            1.53            5.30            7.68
                                 -------------------------------------------------------------------------------
        Ohio Totals.............           62.74           11.35            9.73           35.00          118.82
                                 -------------------------------------------------------------------------------
        Area Totals.............           69.30           13.04           14.72           47.20          144.26
----------------------------------------------------------------------------------------------------------------


[[Page 7986]]


                              Table 5--Area VOC Emissions for Attainment Year 2019
                                                     [TPSD]
----------------------------------------------------------------------------------------------------------------
             County                    Point          Nonroad          Area           Onroad           Total
----------------------------------------------------------------------------------------------------------------
Ohio:
    Butler......................            2.41            2.52           12.28            3.90           21.11
    Clermont....................            0.46            2.17            6.84            2.20           11.67
    Hamilton....................            2.21            6.15           27.26            8.40           44.02
    Warren......................            0.74            2.49            8.88            2.40           14.51
Kentucky:
    Boone.......................            2.75            1.49            7.29            1.30           12.83
    Campbell....................            0.40            0.52            2.23            0.80            3.95
    Kenton......................            0.43            0.74            4.11            1.50            6.78
                                 -------------------------------------------------------------------------------
        Ohio Totals.............            5.82           13.33           55.26           16.90           91.31
                                 -------------------------------------------------------------------------------
        Area Totals.............            9.40           16.08           68.89           20.50          114.87
----------------------------------------------------------------------------------------------------------------


                             Table 6--Change in NOX and VOC Emissions Between 2014 and 2019 for the Ohio Portion of the Area
                                                                         [TPSD]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                NOX                                             VOC
                                                         -----------------------------------------------------------------------------------------------
                                                                                            Net change                                      Net change
                                                               2014            2019         (2014-2019)        2014            2019         (2014-2019)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...................................................           80.04           62.74          -17.30            6.87            5.82           -1.05
Nonroad.................................................           17.94           11.35           -6.59           17.05           13.33           -3.72
Area....................................................           12.33            9.73           -2.60           60.36           55.26           -5.10
Onroad..................................................           62.90           35.00          -27.90           27.00           16.90          -10.10
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................          173.21          118.82          -54.39          111.28           91.31          -19.97
--------------------------------------------------------------------------------------------------------------------------------------------------------


                                   Table 7--Change in NOX and VOC Emissions Between 2014 and 2019 for the Entire Area
                                                                         [TPSD]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                NOX                                             VOC
                                                         -----------------------------------------------------------------------------------------------
                                                                                            Net change                                      Net change
                                                               2014            2019         (2014-2019)        2014            2019         (2014-2019)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...................................................           93.56           69.30          -24.26            9.77            9.40           -0.37
Nonroad.................................................           21.34           13.04           -8.30           21.41           16.08           -5.33
Area....................................................           19.11           14.72           -4.39           76.15           68.89           -7.26
Onroad..................................................           78.40           47.20          -31.20           31.10           20.50          -10.60
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................          212.41          144.26          -68.15          138.43          114.87          -23.56
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Table 7 shows that the Area reduced NO<INF>X</INF> and VOC 
emissions by 68.15 TPSD and 23.56 TPSD, respectively, between 2014 and 
2019. As shown in Table 6, the Ohio portion of the Area alone reduced 
NO<INF>X</INF> and VOC emissions by 54.39 TPSD and 19.97 TPSD, 
respectively, between 2014 and 2019.
3. Meteorology
    To further support OEPA's demonstration that the improvement in air 
quality between the year violations occurred and the year attainment 
was achieved, is due to permanent and enforceable emission reductions 
and not on favorable meteorology, an analysis was performed by the Lake 
Michigan Air Directors Consortium (LADCO). A classification and 
regression tree (CART) analysis was conducted with 2005 through 2020 
data from Area ozone sites that had average ozone concentrations of 
greater than 50 parts per billion (ppb). The goal of the analysis was 
to determine the meteorological and air quality conditions associated 
with ozone episodes, and construct trends for the days identified as 
sharing similar meteorological conditions.
    Regression trees were developed for the Area ozone data to classify 
each summer day by its ozone concentration and associated 
meteorological conditions. By grouping days with similar meteorology, 
the influence of meteorological variability on the underlying trend in 
ozone concentrations is partially removed and the remaining trend is 
presumed to be due to trends in precursor emissions or other non-
meteorological influences. The CART analysis showed the resulting 
trends in ozone concentrations declining over the period examined, 
supporting the conclusion that the improvement in air quality was not 
due to unusually favorable meteorology.

D. Does Ohio have a fully approvable ozone maintenance plan for the 
Area?

    As one of the criteria for redesignation to attainment section 
107(d)(3)(E)(iv) of the CAA requires EPA to determine that the area has 
a fully approved maintenance plan pursuant to section 175A of the CAA. 
Section 175A of the CAA sets forth the elements of a maintenance plan 
for areas seeking redesignation from nonattainment to attainment. Under 
section 175A, the maintenance plan must demonstrate

[[Page 7987]]

continued attainment of the NAAQS for at least 10 years after the 
Administrator approves a redesignation to attainment. Eight years after 
the redesignation, the state must submit a revised maintenance plan 
which demonstrates that attainment of the NAAQS will continue for an 
additional 10 years beyond the initial 10 year maintenance period. To 
address the possibility of future NAAQS violations, the maintenance 
plan must contain contingency measures, as EPA deems necessary, to 
assure prompt correction of the future NAAQS violation.
    The Calcagni Memorandum provides further guidance on the content of 
a maintenance plan, explaining that a maintenance plan should address 
five elements: (1) An attainment emission inventory; (2) a maintenance 
demonstration; (3) a commitment for continued air quality monitoring; 
(4) a process for verification of continued attainment; and (5) a 
contingency plan. In conjunction with its request to redesignate the 
Ohio portion of the Area to attainment for the 2015 ozone standard, 
OEPA submitted a SIP revision to provide for maintenance of the 2015 
ozone standard through 2035, more than 10 years after the expected 
effective date of the redesignation to attainment. As is discussed more 
fully below, EPA proposes to find that Ohio's ozone maintenance plan 
includes the necessary components and is proposing to approve the 
maintenance plan as a revision of the Ohio SIP.
1. Attainment Inventory
    EPA is proposing to determine that the Area has attained the 2015 
8-hour ozone NAAQS based on monitoring data for the period of 2019-
2021. OEPA selected 2019 as the attainment emissions inventory year to 
establish attainment emission levels for VOC and NO<INF>X</INF>. The 
attainment emissions inventory identifies the levels of emissions in 
the Area that are sufficient to attain the 2015 ozone NAAQS. The 
derivation of the attainment year emissions was discussed above in 
section IV.C.2. of this proposed rule. The attainment level emissions, 
by source category, are summarized in Tables 4 and 5 above.
2. Has the state documented maintenance of the ozone standard in the 
Area?
    Ohio has demonstrated maintenance of the 2015 ozone standard 
through 2035 by assuring that current and future emissions of VOC and 
NO<INF>X</INF> for the Area remain at or below attainment year emission 
levels. A maintenance demonstration need not be based on modeling. See 
Wall v. EPA, 265 F.3d 426 (6th Cir. 2001), Sierra Club v. EPA, 375 F. 
3d 537 (7th Cir. 2004). See also 66 FR 53094, 53099-53100 (October 19, 
2001), 68 FR 25413, 25430-25432 (May 12, 2003).
    Ohio is using emissions inventories for the years 2026 and 2035 to 
demonstrate maintenance. 2035 is more than 10 years after the expected 
effective date of the redesignation to attainment and 2026 was selected 
to demonstrate that emissions are not expected to spike in the interim 
between the attainment year and the final maintenance year. The 
emissions inventories were developed as described below.
    To develop the 2026 and 2035 inventories, the state collected data 
from the Ozone NAAQS Emissions Modeling platform (2016v2) inventories 
for the base year 2016 and the 2023, 2026 and 2032 projected 
inventories. 2026 emissions for area, nonroad mobile, AIR, and point 
source sectors were derived from 2026 EPA-projected emissions from the 
2016v2 platform (version 2026fd) without modification. 2035 emissions 
for area, nonroad mobile, AIR, and point source sectors were derived by 
extrapolating from the 2032 EPA-projected emissions from the 2016v2 
platform (version 2032fd) and using the TREND function in Excel. If the 
trend function resulted in a negative value, the emissions were assumed 
to be the same as in 2032. Summer day inventories were derived for 
these sectors using the methodology described in section IV.C.2. above. 
Finally, onroad mobile source emissions were developed in conjunction 
with OKI using the same methodology described in section IV.C.2. above 
for the 2016 inventory. Emissions data are shown in Tables 8 through 13 
below.

                          Table 8--Area NOX Emissions for Interim Maintenance Year 2026
                                                     [TPSD]
----------------------------------------------------------------------------------------------------------------
             County                    Point          Nonroad          Area           Onroad           Total
----------------------------------------------------------------------------------------------------------------
Ohio:
    Butler......................            9.07            1.46            2.02            4.40           16.95
    Clermont....................           10.43            1.07            0.93            2.30           14.73
    Hamilton....................           13.72            4.12            5.03           11.30           34.17
    Warren......................            2.23            1.44            1.00            4.00            8.67
Kentucky:
    Boone.......................            2.13            0.58            3.22            2.60            8.53
    Campbell....................            0.28            0.29            0.70            0.90            2.17
    Kenton......................            0.29            0.41            1.22            2.40            4.32
                                 -------------------------------------------------------------------------------
        Ohio Totals.............           35.45            8.09            8.98           22.00           74.52
                                 -------------------------------------------------------------------------------
        Area Totals.............           38.15            9.37           14.12           27.90           89.54
----------------------------------------------------------------------------------------------------------------


                          Table 9--Area VOC Emissions for Interim Maintenance Year 2026
                                                     [TPSD]
----------------------------------------------------------------------------------------------------------------
             County                    Point          Nonroad          Area           Onroad           Total
----------------------------------------------------------------------------------------------------------------
Ohio:
    Butler......................            1.75            2.24           12.47            2.90           19.36
    Clermont....................            0.19            1.68            7.41            1.60           10.88
    Hamilton....................            1.46            5.53           26.21            6.00           39.20
    Warren......................            0.82            1.86           10.14            1.80           14.62
Kentucky:

[[Page 7988]]

 
    Boone.......................            1.68            1.28            8.21            1.00           12.17
    Campbell....................            0.42            0.40            2.22            0.50            3.54
    Kenton......................            0.64            0.71            4.21            1.00            6.56
                                 -------------------------------------------------------------------------------
        Ohio Totals.............            4.22           11.31           56.23           12.30           84.06
                                 -------------------------------------------------------------------------------
        Area Totals.............            6.96           13.70           70.87           14.80          106.33
----------------------------------------------------------------------------------------------------------------


                             Table 10--Area NOX Emissions for Maintenance Year 2035
                                                     [TPSD]
----------------------------------------------------------------------------------------------------------------
             County                    Point          Nonroad          Area           Onroad           Total
----------------------------------------------------------------------------------------------------------------
Ohio:
    Butler......................            8.31            1.26            1.90            3.30           15.19
    Clermont....................            0.01            0.90            0.81            1.60            3.32
    Hamilton....................            2.66            3.60            4.69            8.60           19.66
    Warren......................            2.05            1.20            0.95            3.00            7.20
Kentucky:
    Boone.......................            2.35            0.54            3.85            2.00            8.74
    Campbell....................            0.28            0.26            0.58            0.60            1.72
    Kenton......................            0.30            0.37            1.06            1.60            3.33
                                 -------------------------------------------------------------------------------
        Ohio Totals.............           13.03            6.96            8.35           16.50           45.37
                                 -------------------------------------------------------------------------------
        Area Totals.............           15.96            8.13           13.84           20.70           59.16
----------------------------------------------------------------------------------------------------------------


                             Table 11--Area VOC Emissions for Maintenance Year 2035
                                                     [TPSD]
----------------------------------------------------------------------------------------------------------------
             County                    Point          Nonroad          Area           Onroad           Total
----------------------------------------------------------------------------------------------------------------
Ohio:
    Butler......................            1.67            2.18           12.65            2.10           18.65
    Clermont....................            0.06            1.54            7.87            1.20           10.67
    Hamilton....................            1.28            5.46           25.54            4.50           36.79
    Warren......................            0.82            1.67           11.18            1.40           15.07
Kentucky:
    Boone.......................            1.68            1.25            8.99            0.80           12.72
    Campbell....................            0.42            0.37            2.22            0.30            3.31
    Kenton......................            0.64            0.72            4.28            0.70            6.34
                                 -------------------------------------------------------------------------------
        Ohio Totals.............            3.83           10.85           57.24            9.20           81.18
                                 -------------------------------------------------------------------------------
        Area Totals.............            6.57           13.19           72.73           11.00          103.55
----------------------------------------------------------------------------------------------------------------


                            Table 12--Change in NOX and VOC Emissions Between 2019 and 2035 for the Ohio Portion of the Area
                                                                         [TPSD]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          NOX                                                 VOC
                                                 -------------------------------------------------------------------------------------------------------
                                                                                        Net change                                          Net change
                                                     2019        2026        2035       (2019-2035)      2019        2026        2035       (2019-2035)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...........................................       62.74       35.45       13.03          -49.71        5.82        4.22        3.83           -1.99
Nonroad.........................................       11.35        8.09        6.96           -4.39       13.33       11.31       10.85           -2.48
Area............................................        9.73        8.98        8.35           -1.38       55.26       56.23       57.24            1.98
Onroad..........................................       35.00       22.00       16.50          -18.50       16.90       12.30        9.20           -7.70
                                                 -------------------------------------------------------------------------------------------------------
    Total.......................................      118.82       74.52       44.84          -73.98       91.31       84.06       81.12          -10.19
--------------------------------------------------------------------------------------------------------------------------------------------------------


[[Page 7989]]


                                   Table 13--Change in NOX and VOC Emissions Between 2019 and 2035 for the Entire Area
                                                                         [TPSD]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          NOX                                                 VOC
                                                 -------------------------------------------------------------------------------------------------------
                                                                                        Net change                                          Net change
                                                     2019        2026        2035       (2019-2035)      2019        2026        2035       (2019-2035)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...........................................       69.30       38.15       15.96          -53.34        9.40        6.96        6.57           -2.83
Nonroad.........................................       13.04        9.37        8.13           -4.91       16.08       13.70       13.19           -2.89
Area............................................       14.72       14.12       13.84           -0.88       68.89       70.87       72.73            3.84
Onroad..........................................       47.20       27.90       20.70          -26.50       20.50       14.80       11.00           -9.50
                                                 -------------------------------------------------------------------------------------------------------
    Total.......................................      144.26       89.54       59.16          -55.10      114.87      106.33      103.55          -11.32
--------------------------------------------------------------------------------------------------------------------------------------------------------

    In summary, the maintenance demonstration for the Area shows 
maintenance of the 2015 ozone standard by providing emissions 
information to support the demonstration that future emissions of 
NO<INF>X</INF> and VOC will remain at or below 2019 emission levels 
when taking into account both future source growth and implementation 
of future controls. Table 13 shows NO<INF>X</INF> and VOC emissions in 
the Area are projected to decrease by 55.10 TPSD and 11.32 TPSD, 
respectively, between 2019 and 2035. As shown in Table 12, 
NO<INF>X</INF> and VOC emissions in the Ohio portion of the Area alone 
are projected to decrease by 73.98 TPSD and 10.19 TPSD, respectively, 
between 2019 and 2035.
3. Continued Air Quality Monitoring
    OEPA has committed to continue to operate the ozone monitors listed 
in Table 1 above. OEPA has committed to consult with EPA prior to 
making changes to the existing monitoring network should changes become 
necessary in the future. Ohio remains obligated to meet monitoring 
requirements and continue to quality assure monitoring data in 
accordance with 40 CFR part 58, and to enter all data into the Air 
Quality System (AQS) in accordance with Federal guidelines.
4. Verification of Continued Attainment
    The State of Ohio has the legal authority to enforce and implement 
the requirements of the maintenance plan for the Ohio portion of the 
Area. This includes the authority to adopt, implement, and enforce any 
subsequent emission control measures determined to be necessary to 
correct future ozone attainment problems.
    Verification of continued attainment is accomplished through 
operation of the ambient ozone monitoring network and the periodic 
update of the area's emissions inventory. OEPA will continue to operate 
the current ozone monitors located in the Ohio portion of the Area. 
There are no plans to discontinue operation, relocate, or otherwise 
change the existing ozone monitoring network other than through 
revisions in the network approved by the EPA.
    In addition, to track future levels of emissions, OEPA will 
continue to develop and submit to EPA updated emission inventories for 
all source categories at least once every three years, consistent with 
the requirements of 40 CFR part 51, subpart A, and in 40 CFR 51.122. 
The Consolidated Emissions Reporting Rule (CERR) was promulgated by EPA 
on June 10, 2002 (67 FR 39602). The CERR was replaced by the Annual 
Emissions Reporting Requirements (AERR) on December 17, 2008 (73 FR 
76539). The most recent triennial inventory for Ohio was compiled for 
2017. Point source facilities covered by Ohio's emission statement 
rule, Ohio Administrative Code Chapter 3745-24, will continue to submit 
VOC and NO<INF>X</INF> emissions on an annual basis.
5. What is the contingency plan for the Area?
    Section 175A of the CAA requires that the state must adopt a 
maintenance plan, as a SIP revision, that includes such contingency 
measures as EPA deems necessary to assure that the state will promptly 
correct a violation of the NAAQS that occurs after redesignation of the 
area to attainment of the NAAQS. The maintenance plan must identify: 
The contingency measures to be considered and, if needed for 
maintenance, adopted and implemented; a schedule and procedure for 
adoption and implementation; and a time limit for action by the state. 
The state should also identify specific indicators to be used to 
determine when the contingency measures need to be considered, adopted, 
and implemented. The maintenance plan must include a commitment that 
the state will implement all measures with respect to the control of 
the pollutant that were contained in the SIP before redesignation of 
the area to attainment in accordance with section 175A(d) of the CAA.
    As required by section 175A of the CAA, Ohio has adopted a 
contingency plan for the Area to address possible future ozone air 
quality problems. The contingency plan adopted by Ohio has two levels 
of response, a warning level response and an action level response.
    In Ohio's plan, a warning level response will be triggered when an 
annual fourth high monitored value of 0.074 ppm or higher is monitored 
within the maintenance area. A warning level response will consist of 
OEPA conducting a study to determine whether the ozone value indicates 
a trend toward higher ozone values or whether emissions appear to be 
increasing. The study will evaluate whether the trend, if any, is 
likely to continue and, if so, the control measures necessary to 
reverse the trend. The study will consider ease and timing of 
implementation as well as economic and social impacts. Implementation 
of necessary controls in response to a warning level response trigger 
will take place within 12 months from the conclusion of the most recent 
ozone season.
    In Ohio's plan, an action level response is triggered when a two-
year average fourth high value of 0.071 ppm or greater is monitored 
within the maintenance area. A violation of the 2015 ozone NAAQS within 
the maintenance area also triggers an action level response. When an 
action level response is triggered, OEPA, in conjunction with the 
metropolitan planning organization or regional council of governments, 
will determine what additional control measures are needed to assure 
future attainment of the 2015 ozone NAAQS. Control measures selected 
will be adopted and implemented within 18 months from the close of the 
ozone season that prompted the action level. OEPA may also consider if 
significant new regulations not currently included as part of the 
maintenance provisions will

[[Page 7990]]

be implemented in a timely manner and would thus constitute an adequate 
contingency measure response.
    OEPA included the following list of potential contingency measures 
in its maintenance plan:
    1. Adopt VOC RACT on existing sources covered by EPA Control 
Technique Guidelines issued after the 1990 CAA.
    2. Apply VOC RACT to smaller existing sources.
    3. One or more transportation control measures sufficient to 
achieve at least half a percent reduction in actual area wide VOC 
emissions. Transportation measures will be selected from the following, 
based upon the factors listed above after consultation with affected 
local governments:
    a. Trip reduction programs, including, but not limited to, 
employer-based transportation management plans, area wide rideshare 
programs, work schedule changes, and telecommuting;
    b. traffic flow and transit improvements; and
    c. other new or innovative transportation measures not yet in 
widespread use that affected local governments deem appropriate.
    4. Alternative fuel and diesel retrofit programs for fleet vehicle 
operations.
    5. Require VOC or NO<INF>X</INF> emission offsets for new and 
modified major sources.
    6. Increase the ratio of emission offsets required for new sources.
    7. Require VOC or NO<INF>X</INF> controls on new minor sources 
(less than 100 tons).
    8. Adopt NO<INF>X</INF> RACT for existing combustion sources.
    9. High volume, low pressure coating application requirements for 
autobody facilities.
    10. Requirements for cold cleaner degreaser operations (low vapor 
pressure solvents).
    To qualify as contingency measure, emissions reductions from that 
measure must not be factored into the emissions projections used in the 
maintenance plan.
    EPA has concluded that the maintenance plan adequately addresses 
the five basic components of a maintenance plan: Attainment inventory, 
maintenance demonstration, monitoring network, verification of 
continued attainment, and a contingency plan. In addition, as required 
by section 175A(b) of the CAA, OEPA has committed to submit to EPA an 
updated ozone maintenance plan eight years after redesignation of the 
Ohio portion of the Area to cover an additional ten years beyond the 
initial 10-year maintenance period. Thus, EPA proposes to find that the 
maintenance plan SIP revision submitted by OEPA for the Ohio portion of 
the Area meets the requirements of section 175A of the CAA and EPA 
proposes to approve it as a revision to the Ohio SIP.

V. Has the state adopted approvable motor vehicle emission budgets?

A. Motor Vehicle Emission Budgets

    Under section 176(c) of the CAA, new 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. Conformity to the SIP means that 
transportation activities will not cause new air quality violations, 
worsen existing air quality problems, or delay timely attainment of the 
NAAQS or interim air quality milestones. Regulations at 40 CFR part 93 
set forth EPA policy, criteria, and procedures for demonstrating and 
assuring conformity of transportation activities to a SIP. 
Transportation conformity is a requirement for nonattainment and 
maintenance areas. Maintenance areas are areas that were previously 
nonattainment for a particular NAAQS, but that have been redesignated 
to attainment with an approved maintenance plan for the NAAQS.
    Under the CAA, states are required to submit, at various times, 
control strategy SIPs for nonattainment areas and maintenance plans for 
areas seeking redesignations to attainment of the ozone standard and 
maintenance areas. See the SIP requirements for the 2015 ozone standard 
in EPA's December 6, 2018 implementation rule (83 FR 62998). These 
control strategy SIPs (including reasonable further progress plans and 
attainment plans) and maintenance plans must include MVEBs for criteria 
pollutants, including ozone, and their precursor pollutants (VOC and 
NO<INF>X</INF> for ozone) to address pollution from onroad 
transportation sources. The MVEBs are the portion of the total 
allowable emissions that are allocated to highway and transit vehicle 
use that, together with emissions from other sources in the area, will 
provide for attainment or maintenance. See 40 CFR 93.101.
    Under 40 CFR part 93, a MVEB for an area seeking a redesignation to 
attainment must be established, at minimum, for the last year of the 
maintenance plan. A state may adopt MVEBs for other years as well. The 
MVEB serves as a ceiling on emissions from an area's planned 
transportation system. The MVEB concept is further explained in the 
preamble to the November 24, 1993, Transportation Conformity Rule (58 
FR 62188). The preamble also describes how to establish the MVEB in the 
SIP and how to revise the MVEB, if needed, subsequent to initially 
establishing a MVEB in the SIP.
    As discussed earlier, Ohio's maintenance plan includes 
NO<INF>X</INF> and VOC MVEBs for the Area for 2035 and 2026, the last 
year of the maintenance period and an interim year. The MVEBS were 
developed as part of an interagency consultation process which includes 
Federal, state, and local agencies. The MVEBS were clearly identified 
and precisely quantified. These MVEBs, when considered together with 
all other emissions sources, are consistent with maintenance of the 
2015 8-hour ozone standard.

                                                    Table 14--MVEBs for the Ohio Portion of the Area
                                                                         [TPSD]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Attainment
                                             year 2019    2026 estimated    2026 mobile                   2035 estimated    2035 mobile
                                              onroad          onroad       safety margin    2026 MVEBs        onroad       safety margin    2035 MVEBs
                                             emissions       emissions      allocation                       emissions      allocation
--------------------------------------------------------------------------------------------------------------------------------------------------------
VOC.....................................           15.58           12.30            1.85           14.15            9.20            1.38           10.58
NOX.....................................           31.90           22.00            3.30           25.30           16.50            2.48           18.98
--------------------------------------------------------------------------------------------------------------------------------------------------------

    As shown in Table 14, the 2026 and 2035 MVEBs exceed the estimated 
2026 and 2035 onroad sector emissions. In an effort to accommodate 
future variations in travel demand models and vehicle miles traveled 
forecast, OEPA allocated a portion of the safety margin (described 
further below) to the mobile sector. Ohio has demonstrated that the 
Area

[[Page 7991]]

can maintain the 2015 ozone NAAQS with mobile source emissions in the 
Ohio portion of the area of 14.15 TPSD and 10.58 TPSD of VOC and 25.3 
TPSD and 18.98 TPSD of NO<INF>X</INF> in 2026 and 2035, respectively, 
since despite partial allocation of the safety margin, emissions will 
remain under attainment year emission levels. EPA is proposing to 
approve the MVEBs for use to determine transportation conformity in the 
Ohio portion of the Area, because EPA has determined that the area can 
maintain attainment of the 2015 ozone NAAQS for the relevant 
maintenance period with mobile source emissions at the levels of the 
MVEBs.

B. What is a safety margin?

    A ``safety margin'' is the difference between the attainment level 
of emissions (from all sources) and the projected level of emissions 
(from all sources) in the maintenance plan. As noted in Table 12, the 
emissions in the Ohio portion of the Area are projected to have safety 
margins of 55.10 TPSD for NO<INF>X</INF> and 11.32 TPSD for VOC in 2035 
(the difference between the attainment year, 2019, emissions and the 
projected 2035 emissions for all sources in the Ohio portion of the 
Area). Similarly, there is a safety margin of 30.38 TPSD for 
NO<INF>X</INF> and 2.78 TPSD for VOC in 2026. Even if emissions reached 
the full level of the safety margin, the counties would still 
demonstrate maintenance since emission levels would equal those in the 
attainment year.
    As shown in Table 14 above, Ohio is allocating a portion of that 
safety margin to the mobile source sector. Specifically, in 2026, Ohio 
is allocating 1.85 TPSD and 3.30 TPSD of the VOC and NO<INF>X</INF> 
safety margins, respectively. In 2035, Ohio is allocating 1.38 TPSD and 
2.48 TPSD of the VOC and NO<INF>X</INF> safety margins, respectively. 
OEPA is not requesting allocation to the MVEBs of the entire available 
safety margins reflected in the demonstration of maintenance. In fact, 
the amount allocated to the MVEBs represents only a small portion of 
the 2026 and 2035 safety margins. Therefore, even though the state is 
requesting MVEBs that exceed the projected onroad mobile source 
emissions for 2026 and 2035 contained in the demonstration of 
maintenance, the increase in onroad mobile source emissions that can be 
considered for transportation conformity purposes is well within the 
safety margins of the ozone maintenance demonstration. Further, once 
allocated to mobile sources, these safety margins will not be available 
for use by other sources.

VI. Proposed Actions

    EPA is proposing to determine that the Area is attaining the 2015 
ozone standard, based on quality-assured and certified monitoring data 
for 2019-2021 and that the Ohio portion of this area has met the 
requirements for redesignation under section 107(d)(3)(E) of the CAA. 
EPA is thus proposing to approve OEPA's request to change the legal 
designation of the Ohio portion of the Area from nonattainment to 
attainment for the 2015 ozone standard. EPA is also proposing to 
approve, as a revision to the Ohio SIP, the state's maintenance plan 
for the area. The maintenance plan is designed to keep the Area in 
attainment of the 2015 ozone NAAQS through 2035. Finally, EPA is 
proposing to approve the newly established 2026 and 2035 MVEBs for the 
Ohio portion of the Area.

VII. Statutory and Executive Order Reviews

    Under the CAA, redesignation of an area to attainment and the 
accompanying approval of a maintenance plan under section 107(d)(3)(E) 
are actions that affect the status of a geographical area and do not 
impose any additional regulatory requirements on sources beyond those 
imposed by state law. A redesignation to attainment does not in and of 
itself create any new requirements, but rather results in the 
applicability of requirements contained in the CAA for areas that have 
been redesignated to attainment. Moreover, 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, 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 that reason, this action:
    <bullet> Is not a significant regulatory action subject to review 
by the Office of Management and Budget under Executive Orders 12866 (58 
FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011);
    <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 (Public Law 104-4);
    <bullet> Does not have federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
    <bullet> Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
    <bullet> Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
    <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; and
    <bullet> Does not provide EPA with the discretionary authority to 
address, as appropriate, disproportionate human health or environmental 
effects, using practicable and legally permissible methods, under 
Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, the SIP is not approved to apply on any Indian 
reservation land or in any other area where EPA or an Indian tribe has 
demonstrated that a tribe has jurisdiction. In those areas of Indian 
country, this rule does not have tribal implications as specified by 
Executive Order 13175 (65 FR 67249, November 9, 2000), because 
redesignation is an action that affects the status of a geographical 
area and does not impose any new regulatory requirements on tribes, 
impact any existing sources of air pollution on tribal lands, nor 
impair the maintenance of ozone national ambient air quality standards 
in tribal lands.

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Intergovernmental relations, Oxides of nitrogen, Ozone, 
Volatile organic compounds.

    Dated: February 4, 2022.
Debra Shore,
Regional Administrator, Region 5.
[FR Doc. 2022-02945 Filed 2-10-22; 8:45 am]
BILLING CODE 6560-50-P


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