Document ID: EPA-R04-OAR-2022-0789-0009
Agency: epa
Document Type: Proposed Rule
Title: Air Quality State Implementation Plans; Approvals and Promulgations: Kentucky; Air Quality Designation; Redesignation of the Kentucky Portion of the Louisville, KY-IN 2015 8-Hour Ozone Nonattainment Area to Attainment
Posted Date: 2023-04-18T04:00Z

[Federal Register Volume 88, Number 74 (Tuesday, April 18, 2023)]
[Proposed Rules]
[Pages 23598-23611]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-08017]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R04-OAR-2022-0789; FRL-10888-01-R4]

Air Plan Approval and Air Quality Designation; KY; Redesignation 
of the Kentucky Portion of the Louisville, KY-IN 2015 8-Hour Ozone 
Nonattainment Area to Attainment

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: On September 6, 2022, the Commonwealth of Kentucky, through 
the Kentucky Energy and Environment Cabinet (Cabinet), Division of Air 
Quality (DAQ), submitted a request for the Environmental Protection 
Agency (EPA) to redesignate the Kentucky portion (hereinafter referred 
to as the ``Louisville, KY Area'' or ``Area'') of the Louisville, 
Kentucky-Indiana, 2015 8-hour ozone nonattainment area (hereinafter 
referred to as the ``Louisville, KY-IN Area'') to attainment for the 
2015 8-hour ozone National Ambient Air Quality Standards (NAAQS or 
standards) and to approve a State Implementation Plan (SIP) revision 
containing a maintenance plan for the Area. EPA is proposing to approve 
the Commonwealth's plan for maintaining attainment of the 2015 8-hour 
ozone standard in the Louisville, KY-IN Area, including the regional 
motor vehicle emission budgets (MVEBs) for nitrogen oxides 
(NOX) and volatile organic compounds (VOC) for the years of 
2019 and 2035 for the Louisville, KY-IN Area, to incorporate the 
maintenance plan into the SIP, and to redesignate the Area to 
attainment for the 2015 8-hour ozone NAAQS. EPA previously approved the 
redesignation request and maintenance plan for the Indiana portion of 
the Louisville, KY-IN Area. EPA is also notifying the public of the 
status of EPA's adequacy determination for the MVEBs for the Area.

DATES: Comments must be received on or before May 18, 2023.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R04-
OAR-2022-0789 at http://www.regulations.gov. Follow the online 
instructions for submitting comments. Once submitted, comments cannot 
be edited or removed from Regulations.gov. EPA may publish any comment 
received to its public docket. Do not submit electronically any 
information you consider to be Confidential Business

[[Page 23599]]

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, the full 
EPA public comment policy, information about CBI or multimedia 
submissions, and general guidance on making effective comments, please 
visit https://www.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: Sarah LaRocca, Air Regulatory 
Management Section, Air Planning and Implementation Branch, Air and 
Radiation Division, U.S. Environmental Protection Agency, Region 4, 61 
Forsyth Street SW, Atlanta, Georgia 30303-8960. The telephone number is 
(404) 562-8994. Ms. Sarah LaRocca can also be reached via electronic 
mail at [email protected].

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Summary of EPA's Proposed Action
II. Background
III. Criteria for Redesignation
IV. Kentucky's SIP Submittal
V. EPA's Analysis of Kentucky's SIP Submittal
VI. EPA's Analysis of Kentucky's Proposed NOX and VOC 
MVEBs
VII. EPA's Adequacy Determination for the Proposed NOX 
and VOC MVEBs
VIII. Effect of EPA's Proposed Actions
IX. Proposed Actions
X. Statutory and Executive Order Reviews

I. Summary of EPA's Proposed Action

    EPA is proposing to take the following separate but related actions 
addressing the September 6, 2022, submittal: (1) to approve Kentucky's 
plan for maintaining the 2015 ozone NAAQS (maintenance plan), including 
the associated MVEBs for the Louisville, KY Area and incorporate the 
plan into the SIP, and (2) to redesignate the Louisville, KY Area to 
attainment for the 2015 8-hour ozone NAAQS. EPA is also notifying the 
public of the status of EPA's adequacy determination for the MVEBs for 
the Louisville, KY Area. The Louisville, KY-IN Area is composed of 
Bullitt, Jefferson, and Oldham Counties in Kentucky, and Clark and 
Floyd Counties in Indiana. These proposed actions are summarized below 
and described in greater detail throughout this notice of proposed 
rulemaking.
    EPA is proposing to approve Kentucky's maintenance plan for its 
portion of the Louisville, KY-IN Area as meeting the requirements of 
section 175A (such approval being one of the Clean Air Act (CAA or Act) 
criteria for redesignation to attainment status) and incorporate it 
into the SIP. The maintenance plan is designed to keep the Louisville, 
KY-IN Area in attainment of the 2015 8-hour ozone NAAQS through 2035. 
The maintenance plan includes 2019 and 2035 MVEBs for NOX 
and VOC for the Louisville, KY-IN Area for transportation conformity 
purposes. EPA is proposing to approve these MVEBs and incorporate them 
into the SIP.
    EPA also proposes to determine that the Louisville, KY Area has met 
the requirements for redesignation under section 107(d)(3)(E) of the 
CAA. Accordingly, EPA is proposing to approve a request to change the 
legal designation of Bullitt, Jefferson, and Oldham Counties in 
Kentucky, as found at 40 CFR part 81, from nonattainment to attainment 
for the 2015 8-hour ozone NAAQS.
    EPA is also notifying the public of the status of EPA's adequacy 
process for the MVEBs for the Louisville, KY-IN Area. The Adequacy 
comment period began on September 14, 2022, with EPA's posting of the 
availability of Kentucky's submission on EPA's Adequacy website 
(https://www.epa.gov/state-and-local-transportation/state-implementation-plans-sip-submissions-currently-under-epa). The Adequacy 
comment period for these MVEBs closed on October 14, 2022. No comments, 
adverse or otherwise, were received during the Adequacy comment period. 
Please see Section VII of this notice of proposed rulemaking for 
further explanation of this process and for more details on MVEBs.
    In summary, this notice of proposed rulemaking is in response to 
Kentucky's September 6, 2022, redesignation request and associated SIP 
submission that addresses the specific issues summarized above and the 
necessary elements described in section 107(d)(3)(E) of the CAA for 
redesignation of the Kentucky portion of the Louisville, KY-IN Area to 
attainment for the 2015 8-hour ozone NAAQS and the associated MVEBs.

II. Background

    On October 1, 2015, EPA revised both the primary and secondary 
NAAQS for ozone to a level of 0.070 parts per million (ppm) to provide 
increased protection of public health and the environment. See 80 FR 
65292 (October 26, 2015). The 2015 ozone NAAQS retains the same general 
form and averaging time as the 0.075 ppm NAAQS set in 2008 but is set 
at a more protective level. Under EPA's regulations at 40 CFR part 50, 
the 2015 8-hour ozone NAAQS is attained when the 3-year average of the 
annual fourth-highest daily maximum 8-hour average ambient air quality 
ozone concentrations is less than or equal to 0.070 ppm. See Appendix U 
of 40 CFR part 50. This 3-year average is referred to as the design 
value.
    Upon promulgation of a new or revised ozone NAAQS, section 107(d) 
of the CAA requires EPA to designate as nonattainment any area that is 
violating the NAAQS (or that contributes to ambient air quality in a 
nearby area that is violating the NAAQS). As part of the designations 
process for the 2015 8-hour ozone NAAQS, the Louisville, KY-IN Area was 
designated as a ``Marginal'' ozone nonattainment area, effective August 
3, 2018. See 83 FR 25776 (June 4, 2018). Areas that were designated as 
Marginal ozone nonattainment areas were required to attain the 2015 8-
hour ozone NAAQS no later than August 3, 2021, based on 2018, 2019, and 
2020 monitoring data. See 40 CFR 51.1303. EPA reclassified the 
Louisville, KY Area to Moderate on October 7, 2022, after failing to 
attain by the attainment date.\1\ See 87 FR 60897 (October 7, 2022) and 
40 CFR 81.318. The October 7, 2022, action requires Moderate areas to 
attain the 2015 8-hour ozone NAAQS as expeditiously as practicable, but 
no later than August 3, 2024, six years after the effective date of the 
initial nonattainment designations. See 40 CFR 51.1303.
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    \1\ EPA proposed to reclassify the Louisville, KY-IN Area as a 
moderate nonattainment area on April 13, 2022. However, prior to 
finalizing the reclassification, EPA redesignated the Indiana 
portion of the Louisville, KY-IN Area to attainment for the 2015 8-
hour ozone NAAQS. See 87 FR 30129 (July 5, 2022). EPA finalized the 
reclassification of the Kentucky portion of the Louisville, KY-IN 
Area on October 7, 2022 (87 FR 60897).
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III. Criteria for Redesignation

    The CAA provides the requirements for redesignating a nonattainment 
area to attainment. Specifically, section 107(d)(3)(E) of the CAA 
allows for redesignation providing that: (1) The EPA Administrator 
determines that the area has attained the applicable NAAQS; (2) the 
Administrator has fully approved the applicable implementation plan for 
the area under section 110(k); (3) the Administrator determines that 
the improvement in air quality is due to permanent and enforceable 
reductions in emissions resulting from implementation of the

[[Page 23600]]

applicable SIP and applicable Federal air pollutant control regulations 
and other permanent and enforceable reductions; (4) the Administrator 
has fully approved a maintenance plan for the area as meeting the 
requirements of section 175A; and (5) the state containing such area 
has met all requirements applicable to the area for purposes of 
redesignation under Section 110 and part D of the CAA.
    EPA provided guidance on redesignation in the General Preamble for 
the Implementation of title I of the CAA Amendments of 1990 on April 
16, 1992 (57 FR 13498) and supplemented that 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 (hereinafter referred to as 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 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 (hereinafter referred to as the ``Shapiro Memorandum'');
    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 (hereinafter referred to as the ``Nichols Memorandum''); 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. Kentucky's SIP Submittal

    On September 6, 2022, Kentucky requested that EPA redesignate the 
Louisville, KY Area to attainment for the 2015 8-hour ozone NAAQS and 
approve the associated SIP revision submitted on the same date 
containing a maintenance plan for the Area. EPA's evaluation indicates 
that the Louisville, KY Area meets the requirements for redesignation 
as set forth in CAA section 107(d)(3)(E), including the maintenance 
plan requirements under CAA section 175A and associated MVEBs. As a 
result of these proposed findings, EPA is proposing to take the actions 
summarized in Section I of this notice. EPA's analysis and rationale 
for this proposal is provided below.

V. EPA's Analysis of Kentucky's SIP Submittal

    As stated above, in accordance with the CAA, EPA proposes to 
approve the 2015 8-hour ozone NAAQS maintenance plan, including the 
associated MVEBs, and incorporate it into the Kentucky SIP, and to 
redesignate the Louisville, KY Area to attainment for the 2015 8-hour 
ozone NAAQS. The five redesignation criteria provided under CAA section 
107(d)(3)(E) are discussed in greater detail for the Area in the 
following paragraphs of this section.

Criterion (1)--The Louisville, KY-IN Area Has Attained the 2015 8-Hour 
Ozone NAAQS

    For redesignating a nonattainment area to attainment, the CAA 
requires EPA to determine that the area has attained the applicable 
NAAQS. See CAA section 107(d)(3)(E)(i). For ozone, an area may be 
considered attaining the 2015 8-hour ozone NAAQS if it meets the 2015 
8-hour ozone NAAQS, as determined in accordance with 40 CFR 50.19 and 
Appendix U of part 50, based on three complete, consecutive calendar 
years of quality-assured air quality monitoring data. To attain the 
2015 8-hour ozone NAAQS, the 3-year average of the annual fourth 
highest daily maximum 8-hour average ozone concentrations measured at 
each monitor within an area must not exceed 0.070 ppm. Based on the 
data handling and reporting convention described in 40 CFR part 50, 
Appendix U, the 2015 8-hour ozone NAAQS are attained if the design 
value is 0.070 ppm or below. The data must be collected and quality-
assured in accordance with 40 CFR part 58 and recorded in EPA's Air 
Quality System (AQS). The monitors generally should have remained at 
the same location for the duration of the monitoring period required 
for demonstrating attainment.
    EPA reviewed complete, quality-assured, and certified ozone 
monitoring data from monitoring stations in the Louisville, KY-IN Area 
for the 2015 8-hour ozone NAAQS for 2019 through 2021 and has 
determined that the design values for each monitor in the Louisville, 
KY-IN Area are equal to or less than the standard of 0.070 ppm for that 
time period. Based on this air quality monitoring data, EPA is 
proposing to determine that the Louisville, KY-IN Area has attained the 
2015 8-hour ozone NAAQS. The fourth-highest 8-hour ozone values at each 
monitor for 2019 through 2021 and the 3-year averages of these values 
(i.e., design values), are summarized in Table 1, below.

[[Page 23601]]

                     Table 1--2019-2021 Ozone Concentrations for the Louisville, KY-IN Area
                                                    [ppm] \2\
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                                                    Annual 4th-highest daily maximum 8-hr ozone    Design value
                                                                   concentration                 ---------------
         AQS site code          County and state ------------------------------------------------
                                                       2019            2020            2021          2019-2021
----------------------------------------------------------------------------------------------------------------
21-029-0006...................  Bullitt, KY.....           0.063           0.065           0.065           0.064
21-185-0004...................  Oldham, KY......           0.065           0.061           0.065           0.063
21-111-0067...................  Jefferson, KY...           0.068           0.071           0.069           0.069
21-111-0051...................  Jefferson, KY...           0.065           0.063           0.067           0.065
21-111-0080...................  Jefferson, KY...           0.064           0.068           0.073           0.068
18-019-0008...................  Clark, IN.......           0.064           0.062           0.063           0.063
18-043-1004...................  Floyd, IN.......           0.063           0.066           0.064           0.064
----------------------------------------------------------------------------------------------------------------

    The highest 3-year design value for 2019-2021 for the Louisville, 
KY-IN Area is 0.069 ppm at the Jefferson County, Kentucky site (21-111-
0067),\3\ which is below the NAAQS. EPA will not take final action to 
approve the redesignation of the Kentucky portion of the Louisville KY-
IN Area if the 3-year design value exceeds the NAAQS prior to EPA 
finalizing the redesignation. Preliminary 2022 ozone monitoring data 
currently indicates attaining 2022 design values for the Louisville, 
KY-IN Area. As discussed in more detail below, Kentucky has committed 
to continue monitoring in this Area in accordance with 40 CFR part 58.
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    \2\ Final air quality design values for all criteria pollutants, 
including ozone, are available at https://www.epa.gov/aqs.
    \3\ The design value for an area is the highest 3-year average 
of the annual fourth-highest daily maximum 8-hour concentration 
recorded at any monitor in the area.
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Criterion (2)--Kentucky Has a Fully Approved SIP Under Section 110(k) 
for the Louisville, KY Area; and Criterion (5)--Kentucky Has Met All 
Applicable Requirements Under Section 110 and Part D of Title I of the 
CAA

    For redesignating a nonattainment area to attainment, 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 
CAA section 107(d)(3)(E)(v), and that the state has a fully approved 
SIP under section 110(k) for the area, see CAA section 
107(d)(3)(E)(ii). EPA proposes to find that Kentucky has met all 
applicable SIP requirements for the Louisville, KY Area under section 
110 of the CAA (general SIP requirements) for purposes of 
redesignation. Additionally, EPA proposes to find that Kentucky has met 
all applicable SIP requirements for purposes of redesignation under 
part D of title I of the CAA in accordance with section 107(d)(3)(E)(v) 
and proposes to determine that the SIP is fully approved with respect 
to all requirements applicable for purposes of redesignation in 
accordance with section 107(d)(3)(E)(ii). In making these proposed 
determinations, EPA ascertained which requirements are applicable to 
the Area and, if applicable, that they are fully approved under section 
110(k). SIPs must be fully approved only with respect to requirements 
that were due prior to submittal of the complete redesignation request.
a. The Louisville, KY Area Has Met All Applicable Requirements Under 
Section 110 and Part D of the CAA
    General SIP requirements. General SIP elements and requirements are 
delineated in section 110(a)(2) of title I, part A of the CAA. These 
requirements include, but are not limited to, the following: submittal 
of a SIP that has been adopted by the state after reasonable public 
notice and hearing; provisions for establishment and operation of 
appropriate procedures needed to monitor ambient air quality; 
implementation of a source permit program; provisions for the 
implementation of part C requirements (Prevention of Significant 
Deterioration (PSD)) and provisions for the implementation of part D 
requirements (NSR permit programs); provisions for air pollution 
modeling; and provisions for public and local agency participation in 
planning and emission control rule development.
    Section 110(a)(2)(D)(i)(I) of the Act, referred to as the ``good 
neighbor provision'' or the ``interstate transport provision,'' 
requires that SIPs 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 the interstate transport of air pollutants. The 
section 110(a)(2)(D)(i)(I) requirements for a state are not linked with 
a particular nonattainment area's designation and classification in 
that state. EPA believes that the requirements linked with a particular 
nonattainment area's designation and classification are the relevant 
measures to evaluate in reviewing a redesignation request. The 
transport SIP submittal requirements, where applicable, continue to 
apply to a state regardless of the designation of any one particular 
area in the state. Thus, EPA does not believe that the CAA's interstate 
transport requirements should be construed to be applicable for 
purposes of redesignation.
    In addition, EPA believes other section 110 elements that are 
neither connected with nonattainment plan submissions nor linked with 
an area's attainment status are not applicable requirements for purpose 
of redesignation. The area will still be subject to these requirements 
after the area is redesignated. 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 61 FR 53174 (October 10, 1996) and 62 FR 
24826 (May 7, 1997) (Reading, Pennsylvania, proposed and final 
rulemakings); 61 FR 20458 (May 7, 1996) (Cleveland-Akron-Loraine, Ohio, 
final rulemaking); and 60 FR 62748, (December 7, 1995) (Tampa, Florida, 
final rulemaking)). See also 65 FR 37890 (June 19, 2000) (discussion on 
this issue in Cincinnati, Ohio, redesignation) and 66 FR 50399 (October 
19, 2001) (Pittsburgh, Pennsylvania, redesignation).
    Title I, part D, applicable SIP requirements. Section 172(c) of the 
CAA sets forth the basic requirements of attainment plans for 
nonattainment areas that are required to submit them pursuant to 
section 172(b). Subpart 2 of

[[Page 23602]]

part D, which includes section 182 of the CAA, establishes specific 
requirements for ozone nonattainment areas depending on the area's 
nonattainment classification. As provided in subpart 2, a Marginal 
ozone nonattainment area must submit an emissions inventory that 
complies with section 172(c)(3), but the specific requirements of 
section 182(a) apply in lieu of the demonstration of attainment (and 
contingency measures) required by section 172(c). See 42 U.S.C. 
7511a(a). A Moderate area must meet the Marginal area requirements of 
section 182(a) and additional requirements specific to Moderate (and 
higher) areas under section 182(b), as well as the general requirements 
of 172(c). A thorough discussion of the requirements contained in 
sections 172(c) and 182 can be found in the General Preamble for 
Implementation of Title I. See 57 FR 13498 (April 16, 1992).
    Under its longstanding interpretation of the CAA, EPA has 
interpreted section 107(d)(3)(E) to mean, as a threshold matter, that 
the part D provisions which are ``applicable'' and which must be 
approved in order for EPA to redesignate an area include only those 
which came due prior to a state's submittal of a complete redesignation 
request. See Calcagni Memorandum. See also Shapiro Memorandum; 60 FR 
12459, 12465-66 (March 7, 1995) (Final Redesignation of Detroit-Ann 
Arbor, Michigan); 68 FR 25418, 25424-27 (May 12, 2003) (Final 
Redesignation of St. Louis, Missouri); and Sierra Club v. EPA, 375 F. 
3d 537, 541 (7th Cir. 2004) (upholding EPA's redesignation rulemaking 
applying this interpretation and expressly rejecting Sierra Club's view 
that the meaning of ``applicable'' under the statute is ``whatever 
should have been in the plan at the time of attainment'' rather than 
``whatever actually was in the plan and already implemented or due at 
the time of attainment'').\4\ For the Louisville, KY Area, no section 
182(b) Part D Moderate nonattainment area requirements for the 2015 8-
hour ozone standard were due at the time that Kentucky submitted its 
redesignation request on September 6, 2022; therefore, these 
requirements are not applicable for the purposes of redesignation. See 
Section II, above (discussing the reclassification of the Louisville KY 
Area to moderate on October 7, 2022). In addition, as discussed below, 
several of the part D requirements under 182(a) are otherwise not 
applicable for the purposes of redesignation and several of the 
requirements have already been satisfied by the Commonwealth.
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    \4\ Applicable requirements of the CAA that become due after the 
area's submittal of a complete redesignation request remain 
applicable until a redesignation is approved but are not required as 
a prerequisite to redesignation. See Calcagni Memorandum; CAA 
section 175A(c).
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    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 NOX emitted within the 
boundaries of the ozone nonattainment area. This required submission 
was due by August 3, 2020, for the Louisville, KY Area. See 40 CFR 
51.1315(a). Kentucky provided an emissions inventory for the Area to 
EPA in a December 22, 2021, SIP submission, and EPA approved the 
emissions inventory in an action published on September 30, 2022. See 
87 FR 59320.
    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) of the CAA (and 
related guidance) 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. Furthermore, 
the Commonwealth complied with this requirement under the 1-hour ozone 
NAAQS for the Jefferson County, Kentucky, portion of the Louisville, 
KY-IN Area. See 59 FR 32343 (June 23, 1994).
    Section 182(a)(2)(B) requires each state with a Marginal or higher 
ozone nonattainment area classification 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 
providing for an I/M program no less stringent than that required prior 
to the 1990 amendments or already in the SIP at the time of the 
amendments, whichever is more stringent. The Louisville, KY Area is not 
subject to the section 182(a)(2)(B) requirement because the Area was 
designated as nonattainment for the 2015 8-hour ozone standard after 
the enactment of the 1990 CAA amendments.
    Regarding the permitting and offset requirements of section 
182(a)(2)(C) and section 182(a)(4), Kentucky currently has a fully 
approved part D NSR program in place. However, EPA has determined that 
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, because PSD 
requirements will apply after redesignation. A more detailed rationale 
for this view is described in the Nichols Memorandum. Kentucky's PSD 
program will become applicable in the Louisville, KY Area upon 
redesignation to attainment.
    Section 182(a)(3) requires states to submit periodic inventories 
and emissions statements. Section 182(a)(3)(A) requires states to 
submit a periodic inventory every three years. As discussed below in 
the section of this notice titled Verification of Continued Attainment, 
the Commonwealth will continue to update its emissions inventory at 
least once every three years. Under section 182(a)(3)(B), each state 
with an ozone nonattainment area must submit a SIP revision requiring 
emissions statements to be submitted to the state by certain sources 
within that nonattainment area. Kentucky provided a SIP revision to EPA 
on October 16, 2020, addressing the section 182(a)(3)(B) emissions 
statements requirements for Oldham and Bullitt Counties, and on April 
26, 2022, EPA published a final rule approving that SIP revision. See 
87 FR 24429 (April 26, 2022). Kentucky provided a SIP revision to EPA 
on August 12, 2020, addressing the section 182(a)(3)(B) emissions 
statements requirements for Jefferson County, and on March 9, 2022, EPA 
published a final rule approving that SIP revision. See 87 FR 13177 
(March 9, 2022).
    Section 182(b) Requirements. Section 182(b) of the CAA, found in 
subpart 2 of part D, establishes additional requirements for Moderate 
(and higher) ozone nonattainment areas. As noted above, no section 
182(b) moderate nonattainment area requirements for the 2015 8-hour 
ozone standard, including RACT under section 182(b)(2), were due at the 
time that Kentucky submitted its redesignation request on September 6, 
2022; therefore, these requirements are not applicable for the purposes 
of redesignation.
    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

[[Page 23603]]

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 \5\ as not applying 
for the 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 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).\6\
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    \5\ 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 the MVEBs that are established in control 
strategy SIPs and maintenance plans.
    \6\ Kentucky has an approved conformity SIP for the Louisville, 
KY Area. See 75 FR 20780 (April 21, 2010).
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    Thus, for the reasons discussed above, EPA proposes to find that 
the Louisville, KY Area has satisfied all applicable requirements for 
purposes of redesignation under section 110 and part D of title I of 
the CAA.
b. The Louisville, KY Area Has a Fully Approved Applicable SIP Under 
Section 110(k) of the CAA
    EPA has fully approved the applicable Kentucky SIP for the 
Louisville, KY Area under section 110(k) of the CAA for all 
requirements applicable for purpose of redesignation. EPA may rely on 
prior SIP approvals in approving a redesignation request, see Calcagni 
Memorandum at p. 3; Southwestern Pennsylvania Growth Alliance v. 
Browner, 144 F.3d 984, 989-90 (6th Cir. 1998); and Wall v. EPA, 265 
F.3d 426 (6th Cir. 2001), plus any additional measures it may approve 
in conjunction with a redesignation action. See 68 FR 25426 (May 12, 
2003) (including citations therein). Kentucky has adopted and 
submitted, and EPA has fully approved at various times, provisions 
addressing various SIP elements applicable for the ozone NAAQS. See 85 
FR 33021 (June 1, 2020) and 85 FR 54507 (September 2, 2020). As 
discussed above, EPA believes that the section 110 elements that are 
neither connected with nonattainment plan submissions, nor linked to an 
area's nonattainment status, are not applicable requirements for 
purposes of redesignation and believes that Kentucky has met all Part D 
requirements applicable for purpose of this redesignation.

Criterion (3)--The Air Quality Improvement in the Louisville, KY-IN 
Area Is Due to Permanent and Enforceable Reductions in Emissions 
Resulting From Implementation of the SIP and Applicable Federal Air 
Pollution Control Regulations and Other Permanent and Enforceable 
Reductions

    For redesignating a nonattainment area to attainment, 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 implementation of the SIP, applicable Federal air pollution 
control regulations, and other permanent and enforceable reductions. 
See CAA section 107(d)(3)(E)(iii). EPA has preliminarily determined 
that Kentucky has demonstrated that the observed air quality 
improvement in the Louisville, KY-IN Area is due to permanent and 
enforceable reductions in emissions resulting from Federal measures and 
from state measures adopted into the SIP and is not the result of 
unusually favorable weather conditions or the COVID-19 pandemic.\7\
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    \7\ Kentucky provided average temperature data from 2001 to 2021 
and precipitation data for 2001 to 2021 showing that meteorological 
conditions were not unusually favorable during 2019 through 2021. 
See section 2.C.iv of the Commonwealth's September 6, 2022, 
redesignation request and SIP revision and the NOAA website for 
further information. https://www.ncdc.noaa.gov/cag. Furthermore, the 
Commonwealth explains that COVID-19 did not influence emissions for 
a long enough timescale to affect the Louisville, KY-IN Area's 
design value. The Commonwealth looked specifically at emissions data 
from 2017 to 2019 to show that reductions within the state started 
occurring before the COVID-19 pandemic. The monitoring data also 
shows that the one-year 4th maximum 8-hour observations did not 
dramatically change between 2019 and 2021. The Commonwealth looked 
at the two largest NOX sources to further support these 
claims and notes that the on-road mobile emissions and EGU emissions 
dipped briefly at the start of the pandemic, but quickly recovered, 
further supporting that permanent and enforceable measures are 
responsible for the attaining 2019-2021 design value and that the 
COVID-19 pandemic was not a factor in the Area's reduced ozone 
levels. Lastly, the Commonwealth confirms with EPA that reductions 
in monitored ozone levels can be contributed to permanent and 
enforceable reductions rather than changes in meteorological 
conditions or temporary reductions due to COVID-19.
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    State measures adopted into the SIP and Federal measures enacted in 
recent years have resulted in permanent emission reductions. Kentucky's 
September 6, 2022, submittal identifies SIP-approved state measures, 
some of which implement Federal requirements, that have been 
implemented to date.\8\ Those measures specifically regulate cement 
kilns and open burning, as well as a variety of other sources, as 
explained in the following paragraphs.
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    \8\ The District's regulatory authority for air pollution 
control in Jefferson County is authorized through KRS Chapter 77.
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    Cement Kilns. Kentucky adopted regulation 401 Kentucky 
Administrative Regulation (KAR) 51:170 to regulate NOX 
emissions from cement kilns, setting a limit of 6.6 lbs per ton of 
clinker produced, averaged over a 30-day period. DAQ has also adopted 
standards for kilns in the Louisville, KY Area.
    Open Burning Bans. Kentucky first incorporated regulation 401 KAR 
63:005 Open Burning into the Kentucky SIP in 1982, with the latest 
revision to the regulation approved on October 17, 2007, and effective 
November 16, 2007. See 72 FR 58759 (October 17, 2007). This regulation 
prohibits most types of open burning from May through September of each 
year in areas that have been or are currently in violation of the ozone 
NAAQS within Kentucky. The Louisville Metro Air Pollution Control 
District (District) similarly prohibits open fires in the Louisville 
Metro area and also prohibits any open burning on any day designated by 
the District as an Air Quality Alert Day, with certain public health 
hazard exceptions.
    Other Sources. Kentucky has regulations in Chapters 59 and 61 of 
Title 401 of the KAR which limit NOX and VOC emissions for 
new and existing sources in various source categories. Jefferson County 
also regulates a variety of sources through regulations on existing and 
new sources in Parts 6 and 7 of its regulations. Jefferson County 
Regulation 6.42 specifically requires NOX and VOC-emitting 
facilities at major NOX-emitting sources and major VOC-
emitting sources, respectively, to propose RACT standards and emissions 
control technology as a source-specific SIP revision.
    Additionally, Federal measures enacted in recent years have also 
resulted in permanent emission reductions in the Louisville, KY Area. 
The Federal measures that have been implemented include the following.
    Tier 2 Emission Standards for Vehicles and Gasoline Sulfur 
Standards. Implementation began in 2004 and as newer, cleaner cars 
enter the national fleet, these standards continue to significantly 
reduce NOX emissions.\9\

[[Page 23604]]

These standards require all passenger vehicles in any manufacturer's 
fleet to meet an average standard of 0.07 grams of NOX per 
mile. Additionally, in January 2006, the sulfur content of gasoline was 
required to be on average 30 ppm which assists in lowering the 
NOX emissions.\10\ EPA expects that these standards will 
reduce NOX emissions from vehicles by approximately 74 
percent, and approximately 86 percent for minivans, light trucks, and 
small SUVs by 2030, translating to nearly 3 million tons annually by 
2030.\11\
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    \9\ EPA, Control of Air Pollution from New Motor Vehicles: Tier 
2 Motor Vehicle Emissions Standards and Gasoline Sulfur Control 
Requirements. See 65 FR 6697 (February 10, 2000).
    \10\ Id. at 6702 (discussing how lower sulfur content results in 
less degradation of catalytic converters).
    \11\ EPA, Regulatory Announcement, EPA420-F-99-051 (December 
1999), available at: https://nepis.epa.gov/Exe/ZyPDF.cgi/P1001Z9W.PDF?Dockey=P1001Z9W.PDF.
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    Tier 3 Motor Vehicle Emission and Fuel Standards.12 
Implementation began in 2017 and will continue to phase in through 
2025.\13\ These standards set new vehicle emissions standards and lower 
the allowed sulfur content of gasoline in order to reduce air pollution 
from passenger cars and trucks. Tailpipe and evaporative emissions will 
be reduced for passenger cars, light-duty trucks, medium-duty passenger 
vehicles, and some heavy-duty vehicles. The Tier 3 vehicle standards 
for light-duty vehicles, light-duty trucks, and medium-duty passenger 
vehicles will be a fleet average standard of 0.03 gram of non-methane 
organic gases (NMOG) + NOX per mile as measured on the 
Federal Test Procedure (FTP), and a fleet average standard 0.05 gram of 
NMOG + NOX per mile as measured on the Supplemental Federal 
Test Procedure (SFTP). The Tier 3 vehicle standards for heavy-duty 
pickup trucks and vans will be 0.178 gram per mile of non-methane 
organic gases (NMOG) + NOX for Class 2b vehicles and 0.247 
gram per mile of NMOG + NOX for Class 3 vehicles, as 
measured on the FTP. This standard required Federal gasoline to meet an 
annual average standard of 10 ppm of sulfur by January 1, 2017. The 
Tier 3 tailpipe standards for light-duty vehicles will reduce the fleet 
average standards for the sum of NMOG and NOX, NMOG + 
NOX, by approximately 80 percent from the current fleet 
average standards, and will reduce the per-vehicle particulate matter 
(PM) standards by 70 percent. The Tier 3 program for heavy-duty 
vehicles will reduce the fleet average standards for NMOG + 
NOX and PM by approximately 60 percent from the current 
fleet average standards. The Tier 3 program is also reducing the 
evaporative VOCs by approximately 50 percent from the current 
standards, and these standards apply to all light-duty and on-road 
gasoline-powered heavy-duty vehicles.
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    \12\ In its submittal, Kentucky refers to this as the Tier 3 
Emission Standards for Vehicles and Gasoline Sulfur Standards.
    \13\ See 79 FR 23414 (April 28, 2014).
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    Heavy-Duty Engine and Vehicle Standards and Highway Diesel Fuel 
Sulfur Control Requirements.14 EPA issued this rule in 2001. 
See 66 FR 5002 (January 18, 2001). This rule includes standards 
limiting the sulfur content of diesel fuel, which went into effect in 
2004. A second phase took effect in 2007, which further reduced the 
highway diesel fuel sulfur content to 15 ppm, leading to additional 
reductions in combustion NOX and VOC emissions.\15\ EPA 
expects that this rule will achieve a 95 percent reduction in 
NOX emissions from diesel trucks and buses and will reduce 
NOX emissions by 2.6 million tons by 2030 when the heavy-
duty vehicle fleet is completely replaced with newer heavy-duty 
vehicles that comply with these emission standards.\16\
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    \14\ The Kentucky submittal refers to this as the Heavy-Duty 
Gasoline and Diesel Highway Vehicle Standards & Ultra Low-Sulfur 
Diesel Rule.
    \15\ See 66 FR 5002 (January 18, 2001) (explaining that the new 
emissions standards ``are based on the use of high-efficiency 
catalytic exhaust emission control devices or comparably effective 
advanced technologies. Because these devices are damaged by sulfur, 
we are also reducing the level of sulfur in highway diesel fuel 
significantly by mid-2006.'').
    \16\ See id. at 5012.
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    Control of Emissions of Air Pollution from Nonroad Diesel Engines 
and Fuel.\17\ This rule was promulgated in 2004 and was phased in 
between 2008 through 2015. See 69 FR 38957 (June 29, 2004). This rule 
reduced the sulfur content in the nonroad diesel fuel and reduced 
NOX, VOC, particulate matter, and carbon monoxide emissions. 
This rule applies to diesel engines and fuel used in industries such as 
construction, agriculture, industrial, and mining. EPA estimated that 
this rule will decrease NOX emissions nationally by 738,000 
tons by 2030. EPA estimates that this rule will cut NOX from 
non-road diesel engines by approximately 90 percent.
---------------------------------------------------------------------------

    \17\ The Kentucky submittal refers to this rule as Tier 4 
Nonroad Engine Standards.
---------------------------------------------------------------------------

    National Greenhouse Gas (GHG) Emission Standards for Passenger Cars 
and Light Trucks. In 2010 and 2012, EPA issued rulemakings for Federal 
GHG and fuel economy standards that apply to light-duty cars and trucks 
in model years 2012-2016 (phase 1) and 2017-2025 (phase 2).\18\ The 
final standards are projected to result in an average industry fleet-
wide level of 163 grams/mile in carbon dioxide which is equivalent to 
54.5 miles per gallon if achieved exclusively through fuel economy 
improvements. The fuel economy standards result in less fuel being 
consumed and, therefore, slightly less VOC emissions released.
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    \18\ Final Rule for Model Year 2012-2016 Light Duty Vehicle and 
Greenhouse Gas Emission Standards and Corporate Average Fuel Economy 
Standards, 75 FR 25324 (May 7, 2010); and Final Rule for 2017 and 
Later Model Year Light-Duty Vehicle Greenhouse Gas Emissions and 
Corporate Average Fuel Economy Standards, 77 FR 62624 (October 15, 
2012).
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    EPA issued the Safer Affordable Fuel-Efficient (SAFE) Vehicles Rule 
on March 20, 2020, as an update to Phase 2. This new standard sets fuel 
economy and CO2 standards that increase 1.5 percent in 
stringency each year from model years 2021 through 2026 and applies to 
passenger cars and light trucks. On February 8, 2021, the D.C. Circuit 
issued an order granting the Federal Government's motion to stay 
litigation over the SAFE Vehicles Rule (Union of Concerned Scientists 
v. NHTSA, Case No. 19-1230 (D.C. Cir.)).
    On December 30, 2021, EPA published the Revised 2023 and Later 
Model Year Light-Duty Vehicle Greenhouse Gas Emissions Standards 
(Revised 2023 GHG Standards). See 86 FR 74434. The Revised 2023 GHG 
Standards revised, and made more stringent, the GHG standards in each 
model year from 2023 through 2026.\19\ The action also includes 
temporary targeted flexibilities to address the lead time of the final 
standards and to incentivize the production of vehicles with zero and 
near-zero emissions technology and EPA made technical amendments to 
clarify and streamline regulations. These standards will result in a 
reduction in GHG emissions. They will also result in a net reduction in 
NOX emissions by 2050.
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    \19\ The Revised 2023 GHG Standards revised GHG standards to be 
more stringent than those from in the ``The Safer Affordable Fuel-
Efficient (SAFE) Vehicles Rule for Model Years 2021-2026 Passenger 
Cars and Light Trucks,'' which had previously been stayed by the 
D.C. Circuit. See Order, Union of Concerned Scientists v. NHTSA, No. 
19-1230 (D.C. Cir. Feb. 8. 2021)).
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    National Emission Standards for Hazardous Air Pollutants from Coal- 
and Oil-Fired Electric Utility Steam Generating Units and Standards of 
Performance for Fossil-Fuel-Fired Electric Utility, Industrial-
Commercial-Institutional, and Small Industrial-Commercial-Institutional 
Steam Generating Units.20 The Mercury and Air Toxics 
Standard (MATS) and the new source performance standard

[[Page 23605]]

(NSPS) were published in 2012. See 77 FR 9304 (February 16, 2012). MATS 
was promulgated to reduce emissions of heavy metals, including mercury 
(Hg), arsenic (As), chromium (Cr), and nickel (Ni); and acid gases, 
including hydrochloric acid (HCl) and hydrofluoric acid (HF) from new 
and existing coal and oil-fired electric utility steam generating units 
(EGUs). The MATS compliance date for new sources was April 16, 2012, 
and April 16, 2015, for existing sources.
---------------------------------------------------------------------------

    \20\ Kentucky's submittal refers to these as Utility Mercury Air 
Toxics Standards (MATS) and New Source Performance Standards (NSPS).
---------------------------------------------------------------------------

    National Emission Standards for Hazardous Air Pollutants (NESHAPs) 
for Major Sources: Industrial, Commercial, and Institutional Boilers 
and Process Heaters; National Emissions Standards for Hazardous Air 
Pollutants for Stationary Reciprocating Internal Combustion 
Engines.21 The NESHAP for industrial, commercial, and 
institutional boilers (40 CFR part 63 subpart DDDDD) and the NESHAP for 
Reciprocating Internal Combustion Engines (RICE) (40 CFR part 63 
subpart ZZZZ) are projected to reduce VOC emissions. The former applies 
to boiler and process heaters located at major sources of hazardous air 
pollutants (HAPs) that burn natural gas, fuel oil, coal, biomass, 
refinery gas, or other gas and had a compliance deadline of January 31, 
2016. The latter applies to existing, new, or reconstructed stationary 
RICE located at major or area sources of HAPs, excluding stationary 
RICE being tested at a stationary RICE test cell, and has various 
compliance dates from August 16, 2004, to October 19, 2013, depending 
on the type of source and date of construction or reconstruction.
---------------------------------------------------------------------------

    \21\ The Kentucky submittal refers to these as the Boiler and 
Reciprocating Internal Combustion Engine (RICE) National Emissions 
Standards for Hazardous Air Pollutants (NESHAP).
---------------------------------------------------------------------------

    Nonroad Spark-Ignition Engines and Recreational Engines 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 were 
phased in from model year 2004 through 2012. When fully implemented by 
2030, EPA estimates an overall 75 percent reduction in VOC emissions 
and an 82 percent reduction in NOX emissions. These controls 
reduce ambient concentrations of ozone, carbon monoxide, and fine 
particulate matter.
    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 
applied beginning in 2011 and are expected to result in a 15 to 25 
percent reduction in NOX emissions from these engines. Final 
Tier 3 emission standards applied beginning in 2016 and are expected to 
result in approximately an 80 percent reduction in NOX from 
these engines.
    Transport Rulemakings. In any given location, ozone pollution 
levels are impacted by a combination of background ozone concentration, 
local emissions, and emissions from upwind sources resulting from ozone 
transport. Downwind states' ability to meet health-based air quality 
standards such as the NAAQS may be impacted by the transport of ozone 
pollution across state borders. See, e.g., 87 FR 20036 (April 6, 2022). 
EPA acknowledges the historical account in Kentucky's September 6, 
2022, submittal of national interstate transport rules and associated 
NOX ozone season trading programs \22\ that addressed 
interstate transport for previous 1979 1-hour, 1997 8-hour, and the 
2008 8-hour ozone NAAQS. These programs have provided some benefits in 
the form of NOX ozone season emission reductions for certain 
sources in the Commonwealth and regionally.
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    \22\ Kentucky's September 6, 2022, redesignation request 
identifies the following rules: October 27, 1998, NOX SIP 
Call (63 FR 57356); 2005 Clean Air Interstate Rule (CAIR) (70 FR 
25162); 2011 Cross-State Air Pollution Rule (CSAPR) (76 FR 48208); 
and 2016 CSAPR Update (81 FR 74504). The NOX SIP Call 
(including the NOX Budget Trading Program) and CAIR were 
established to reduce NOX ozone season emissions from 
EGUs and large non-EGUs for the 1-hour 1979 and 8-hour 1997 ozone 
standards. See 67 FR 17624 (April 11, 2002), 74 FR 54755 (October 
23, 2009) and 72 FR 56623 (October 4, 2007). The NOX SIP 
call NOX Budget trading program provided NOX 
emission reduction for EGUs and non-EGUs for older ozone NAAQS. 
Kentucky's redesignation request is not relying on this the 
NOX SIP Call NOX budget trading program for 
the purpose of demonstrating permanent and enforceable measures that 
attribute to the demonstration of attainment for the current and 
more stringent 2015 8-hour ozone standard. Kentucky's redesignation 
request is also not relying on CAIR to demonstrate attainment of the 
2015 ozone NAAQS for the Louisville KY-IN Area and explicitly states 
that NOX reductions achieved as a result of CAIR are not 
reflected in the emissions inventory and projections for the 
Kentucky portion of the Louisville KY-IN Area. EPA notes that the 
CAIR and the NOX SIP Call NOX Budget Trading 
programs are no longer federally enforceable due to subsequent NAAQS 
interstate transport obligations and legal challenges (North 
Carolina v. EPA, 531 F.3d 896 (D.C. Cir. 2008)). However, the 
Commonwealth still has ongoing NOX SIP call obligations 
pursuant to 40 CFR 51.121.
    The group of CSAPRs addressed the 1997 ozone and 
PM2.5 standards, 2006 PM2.5 and 2008 ozone 
NAAQS. See 76 FR 48208 (August 8, 2011) and 81 FR 74504 (October 26, 
2016). However, the NOX ozone season trading programs 
have not been approved into the Kentucky SIP. On March 15, 2023, EPA 
finalized a FIP for 23 states, including Kentucky, to address 
interstate transport downwind air quality issues for the 2015 ozone 
NAAQS. A pre-publication version of the final FIP can be found on 
EPA's website. See https://www.epa.gov/csapr/good-neighbor-plan-2015-ozone-naaqs. The final rule issues NOX emission 
budgets for EGUs in 22 states to participate in an allowance-based 
ozone season trading program beginning in 2023.
---------------------------------------------------------------------------

    EPA proposes to find that the improvements in air quality in the 
Louisville, KY Area are due to real, permanent and enforceable 
reductions in NOX and VOC emissions resulting from the 
federal and SIP-approved state measures discussed above.

Criterion (4)--The Louisville, KY Area Has a Fully Approved Maintenance 
Plan Pursuant to Section 175A of the CAA

    For redesignating a nonattainment area to attainment, the CAA 
requires EPA to determine that the area has a fully approved 
maintenance plan pursuant to section 175A of the CAA. See CAA section 
107(d)(3)(E)(iv). In conjunction with its request to redesignate the 
Louisville, KY Area to attainment for the 2015 8-hour ozone NAAQS, 
Kentucky submitted a SIP revision to provide for the maintenance of the 
2015 8-hour ozone NAAQS for at least 10 years after the effective date 
of redesignation to attainment. EPA has made the preliminary 
determination that this maintenance plan meets the requirements for 
approval under section 175A of the CAA.
a. What is required in a maintenance plan?
    Section 175A of the CAA sets forth the elements of a maintenance 
plan for areas seeking redesignation from nonattainment to attainment. 
Pursuant to section 175A, the plan must demonstrate continued 
attainment of the applicable 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 will continue to be maintained for 
the remainder of the 20-year period following the initial 10-year 
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 any future 2015 8-hour ozone 
violations. The Calcagni Memorandum provides further guidance on the 
content of a maintenance plan, explaining that a maintenance plan 
should address five requirements: the attainment emissions inventory, 
maintenance demonstration, monitoring plan, verification of continued 
attainment, and a contingency plan. As discussed more fully below, EPA 
has

[[Page 23606]]

preliminarily determined that Kentucky's maintenance plan includes all 
the necessary components and is thus proposing to approve it as a 
revision to the Kentucky SIP.
b. Attainment Emissions Inventory
    As discussed above, the Louisville, KY-IN Area has an attaining 
design value for the 2015 8-hour ozone NAAQS based on quality-assured 
monitoring data for the 3-year period from 2019-2021.\23\ The 
Louisville, KY-IN Area's preliminary 2020-2022 design value currently 
indicates that the area will likely continue to attain the 2015 ozone 
NAAQS. Kentucky selected 2019 as the base year (i.e., attainment 
emissions inventory year) for developing a comprehensive emissions 
inventory for NOX and VOC, from which projected emissions 
could be developed for 2025, 2030, and 2035. The attainment inventory 
identifies a level of emissions in the Area that is sufficient to 
attain the 2015 8-hour ozone NAAQS. Kentucky began development of the 
attainment inventory by first generating a baseline emissions inventory 
for the Area. The 2019 base year emissions were projected to 2035 for 
EGU point sources, non-EGU point sources, area sources, non-road mobile 
sources, and on-road mobile sources. The Commonwealth projected summer 
day emission inventories using projected rates of growth in population, 
traffic, economic activity, and other parameters. In addition to 
comparing the final year of the plan (2035) to the 2019 base year, 
Kentucky compared interim years to the baseline to demonstrate that 
these years are also expected to show continued maintenance of the 2015 
8-hour ozone standard.
---------------------------------------------------------------------------

    \23\ Final air quality design values for all criteria 
pollutants, including ozone, are available at https://www.epa.gov/aqs. These design values are calculated in accordance with 40 CFR 
part 50.
---------------------------------------------------------------------------

    The emissions inventory is composed of four major types of sources: 
Point, non-point, on-road, and non-road mobile. Complete descriptions 
of how the Commonwealth developed these inventories are located in 
Appendices A, B, C, and D of the September 6, 2022, SIP submittal.
Point Sources
    For point sources, Kentucky developed the 2019 attainment year 
inventory using emissions collected by the District and the Division 
directly for all sources, with the exception of airports and railyards, 
which were developed using the 2017 NEI.
    To calculate tons per ozone season/tons per summer day (tpsd) 
emissions, Kentucky used two methods, depending on whether a source 
reported seasonal operations or annual operations. With respect to 
point sources in the Louisville, KY Area that reported seasonal 
operations, Kentucky used that seasonal data to calculate summer 
emissions by dividing by 92 days (for the summer months of June, July 
and August). With respect to sources reporting annual data, Kentucky 
calculated tons per summer day emissions were by dividing annual 
emissions by four and then by the 92 days of summer.\24\
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    \24\ This calculation method for estimating summer day emissions 
is supported by the fact that the average summer (June, July, and 
August) emissions from these point sources were estimated to be 
approximately 24.6 to 26.3 percent of the annual total. Further 
supporting this estimation method, a review of data on monthly 
flights from the Louisville International Airport indicates that 
flights in June, July, and August made up almost precisely one 
quarter of total annual flights (25.1 percent).
---------------------------------------------------------------------------

    In order to develop projected year emissions, Kentucky used EPA's 
2016v2 modeling platform. The 2016v1 emissions modeling platform is a 
product from the National Emissions Inventory Collaborative, a 
collaboration between state and regional air agencies, EPA, and Federal 
Land Management agencies, and includes a full suite of base year (2016) 
and projection year (2023 and 2028) inventories, ancillary emission 
data, and scripts and software for preparing the emissions for air 
quality modeling. The 2016v2 emissions modeling platform was developed 
by EPA as an update to the 2016v1 platform because new data, model 
versions, and methods became available following the release of 
2016v1.\25\ In addition, 2016v2 makes use of a new inventory method for 
solvents, includes minor corrections to the wildfire inventory, and 
corrects for double counting of the airport emissions. The commercial 
marine vessel and rail inventories are consistent with the 2016v1 
inventories. The 2016v2 platform includes emissions for the years 2016, 
2023, 2026, and 2032. Summer day emissions were determined by using 
county monthly emissions for 2023, 2026, and 2032 for June through 
August each year from 2016v2 Platform reports, by category within each 
county for each pollutant, and divided by 92 days to calculate tons per 
summer day, which was then used to interpolate emissions for 2025, 
2030, and 2035 using Microsoft Excel's TREND function.\26\
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    \25\ The 2016 v2 platform incorporates emissions based on 
MOVES3, the 2017 NEI nonpoint inventory, the Western Regional Air 
Partnership oil and gas inventory, and updated inventories for 
Canada and Mexico.
    \26\ See page 15 of Louisville's September 6, 2022, submittal.
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Non-Point Sources
    For non-point sources, the 2019 attainment year inventory was 
developed using the 2017 NEI and with future year inventories from the 
EPA 2016v2 modeling platform and Microsoft TREND Function (linear 
regression). The 2019 emissions were interpolated based on 2017 NEI 
emissions and 2023, 2028, and 2032 projected emissions.\27\
---------------------------------------------------------------------------

    \27\ Per EPA guidance, the non-point emissions inventory did not 
include biogenic sources and fires. See EPA, Emissions Inventory 
Guidance for Implementation of Ozone and Particulate Matter National 
Ambient Air Quality Standards (NAAQS) and Regional Haze Regulations 
(May 2017) at 42, 48, 57, available at https://www.epa.gov/sites/default/files/2017-07/documents/ei_guidance_may_2017_final_rev.pdf.
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    EPA's 2016v2 was used to develop non-point projected year emissions 
in the same manner as described above for point sources.
On-Road Sources
    The 2019 on-road emissions in the Kentucky submittal and all 
projected years inventories were developed using the most recent 
information from the travel demand model (TDM) designed by Kentuckiana 
Regional Planning and Development Agency (KIPDA) and data obtained from 
EPA MOVES3 (Motor Vehicle Emissions Simulator).\28\ KIPDA is the 
metropolitan planning organization for the Louisville, KY-IN area. This 
updated data for mobile source emissions is located in Appendix B to 
Kentucky's submittal, available in the docket for this proposed action.
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    \28\ See the Response to Comment and Statement of Consideration 
documents included in Appendix N of Kentucky's submittal.
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Non-Road Sources
    Some non-road mobile emissions in the U.S. are from the non-road 
equipment segment (i.e., agricultural equipment, construction 
equipment, lawn and garden equipment, and recreational vehicles such as 
boats and jet-skis). For non-road sources, the 2019 attainment year 
inventory was developed using the 2017 NEI and with future year 
inventories from the EPA 2016v2 modeling platform and Microsoft TREND 
Function. The 2019 emissions were interpolated based on 2017 NEI 
emissions and 2023, 2028, and 2032 projected emissions. EPA's 2016v2 
was used to develop non-road projected year emissions in the same 
manner as described above for point sources.
    The 2019 base year inventory for the Area, as well as the projected

[[Page 23607]]

inventories for other years, were developed consistent with EPA 
guidance and are summarized in Tables 2 and 3 of the following 
subsection discussing the maintenance demonstration.
c. Maintenance Demonstration
    The redesignation request includes a maintenance plan which 
includes the following features:
    (i) Shows compliance with and maintenance of the 2015 8-hour ozone 
NAAQS by providing information to support the demonstration that 
current and future emissions of NOX and VOC remain at or 
below 2019 emissions levels.
    (ii) Uses 2019 as the attainment year and includes future emissions 
inventory projections for 2025, 2030, and 2035. The 2019 emissions were 
calculated by linear interpolation between 2017 and 2023. Emissions for 
2025, 2030, and 2035 were calculated by linear interpolation using 
2023, 2026 and 2032.\29\
---------------------------------------------------------------------------

    \29\ All three years of projected emissions were used to 
interpolate/extrapolate for the inventory; however, using the two 
closest years (e.g., 2023 and 2026 to interpolate 2025), was 
evaluated as an alternative but resulted in less than one ton per 
summer day difference in NOX projections each year except 
2035, where use of 2026 and 2032 alone resulted in a greater drop 
than use of all three years. Use of all three years was retained as 
the more conservative approach (i.e., an approach that produced 
higher projected emissions).
---------------------------------------------------------------------------

    (iii) Identifies an ``out year'' at least 10 years after the time 
necessary for EPA to review and approve the maintenance plan. Per 40 
CFR part 93, NOX and VOC MVEBs were established for the last 
year (2035) of the maintenance plan as well as for the base year of 
2019 (see Section VI, below).\30\
---------------------------------------------------------------------------

    \30\ Kentucky interpolated 2019 emissions using the TREND 
function based on the 2017 NEI emissions and 2023, 2028, and 2032 
projected emissions. Emissions from 2017 as well as projections from 
all future years were chosen to interpolate 2019 by using just the 
two closest years (2017 and 2023).
---------------------------------------------------------------------------

    (iv) Provides actual (2019) and projected emissions inventories, in 
tpsd, for the Louisville, KY Area, as shown in Tables 2 and 3, below.

 Table 2--Actual and Projected Average Summer Day NOX Emissions for the
                           Louisville, KY Area
                                 [tpsd]
------------------------------------------------------------------------
               Source                   2019     2025     2030     2035
------------------------------------------------------------------------
Point...............................    34.04    29.22    29.09    28.97
Non-point...........................     7.62     6.04     5.94     5.84
On-road.............................    25.31    14.22    11.08    10.26
Non-road............................     4.00     3.12     2.91     2.69
                                     -----------------------------------
    Total...........................    70.97    52.60    49.02    47.76
------------------------------------------------------------------------

 Table 3--Actual and Projected Average Summer Day VOC Emissions for the
                           Louisville, KY Area
                                 [tpsd]
------------------------------------------------------------------------
               Source                   2019     2025     2030     2035
------------------------------------------------------------------------
Point...............................    33.47    23.42    23.61    23.80
Non-point...........................    37.11    31.92    32.40    32.89
On-road.............................    10.28     5.39     3.94     3.46
Non-road............................     4.72     4.33     4.31     4.28
                                     -----------------------------------
    Total...........................    85.58    65.06    64.26    64.43
------------------------------------------------------------------------

    Tables 2 and 3 summarize the 2019 and future projected emissions of 
NOX and VOC in the Louisville, KY Area. In situations where 
local emissions were the primary contributor to nonattainment, such as 
the Louisville, KY Area, if the future projected emissions in the 
nonattainment area remain at or below the baseline emissions in the 
nonattainment area, then the related ambient air quality standard 
should not be exceeded in the future. Kentucky has projected emissions 
as described previously and determined that emissions in the 
Louisville, KY Area will remain below those in the attainment year 
inventory for the duration of the maintenance plan.
    As discussed in Section VI, below, 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. The attainment level of emissions is the level of 
emissions during one of the years in which the area met the NAAQS. 
Kentucky selected 2019 as the attainment emissions inventory year for 
the Louisville, KY Area and calculated safety margins for 2035 (see 
Table 4). Because the interim MVEB year of 2019 is also the base year 
for the maintenance plan inventory, there is no safety margin for 2019; 
therefore, no adjustments were made to the MVEBs for 2019. Kentucky, in 
consultation with the Louisville, KY-IN Area transportation partners, 
allocated a portion of the available safety margin to the 2035 MVEBs 
for the entire Louisville, KY-IN Area.

         Table 4--Safety Margins for the Louisville, KY-IN Area
                                 [tpsd]
------------------------------------------------------------------------
                         Year                             NOX      VOC
------------------------------------------------------------------------
2035..................................................    30.17    23.18
------------------------------------------------------------------------

    Kentucky has allocated 2.98 tpsd (9.9 percent) of the available 
NOX safety margin to the 2035 NOX MVEB and 0.83 
tpsd (3.6 percent) of the available VOC safety margin to the 2035 VOC 
MVEB to allow for, among other things, unanticipated growth in VMT and 
changes and uncertainty in vehicle mix assumptions that will influence 
the emission estimations. After allocation of the available safety 
margin, the remaining safety margin is 27.19 tpsd for NOX 
and 22.35 tpsd for VOC. This allocation and the resulting available

[[Page 23608]]

safety margin for the Louisville, KY Area are discussed further in 
section VI of this notice along with the MVEBs to be used for 
transportation conformity purposes.
d. Monitoring Network
    There are seven ozone monitors in the Louisville, KY-IN Area; five 
in the Kentucky portion and two in the Indiana portion. Kentucky will 
continue to operate the monitors in the Kentucky portion of the 
Louisville, KY-IN Area in compliance with 40 CFR part 58 and has thus 
addressed the requirement for the monitoring. EPA approved Kentucky's 
2021 ambient air monitoring network plan on October 27, 2021.
e. Verification of Continued Attainment
    Kentucky, through the Cabinet and District, has the legal authority 
to enforce and implement the maintenance plan for the Area. This 
includes the authority to adopt, implement, and enforce any subsequent 
emissions control contingency measures determined to be necessary to 
correct future ozone attainment problems.
    Additionally, under the Air Emissions Reporting Requirements (AERR) 
(40 CFR part 51, subpart A), every three years the Cabinet and Division 
are required to develop a comprehensive, annual, statewide emissions 
inventory that is due twelve to eighteen months after the completion of 
the inventory year. Both the Cabinet and Division will update the AERR 
inventory every three years and will use the updated emissions 
inventory to track the progress of maintenance of the NAAQS. The 
maintenance plan states that emissions information will be compared to 
the 2019 attainment year and the 2035 projected maintenance year 
inventories to assess emission trends, as necessary, and to assure 
continued compliance with the standard.
f. Contingency Measures in the Maintenance Plan
    Section 175A of the CAA requires that a maintenance plan include 
such contingency measures as EPA deems necessary to assure that the 
state will promptly correct a violation of the NAAQS that occurs after 
redesignation. The maintenance plan should identify the contingency 
measures to be adopted, a schedule and a procedure for adoption and 
implementation, and a time limit for action by the state. A state 
should also identify specific indicators to be used to determine when 
the contingency measures need to be implemented. The maintenance plan 
must include a requirement that a state will implement all measures 
with respect to control of the pollutant that were contained in the SIP 
before redesignation of the area to attainment in accordance with 
section 175A(d).
    In the September 6, 2022, submittal, Kentucky states that, at a 
minimum, contingency measures must include all measures with respect to 
the control of ozone contained in the SIP for the Area before the 
redesignation, that all such measures are in effect for the Area, and 
that DAQ and the District will continue to implement these measures. 
The contingency measures in the maintenance plan include a two-tiered 
triggering mechanism to determine when contingency measures are needed 
and a process of developing and implementing appropriate control 
measures.
    Kentucky refers to the first-tier response as an ``indicator'' 
response. An indicator response is triggered if (1) there is an annual 
fourth high monitored value of 0.071 ppm or greater in a single ozone 
season or (2) periodic emission inventory updates reveal excessive or 
unanticipated growth greater than 10 percent in ozone precursor 
emissions within the Area. For the indicator response, Kentucky will 
evaluate existing control measures to see if further emission reduction 
measures should be implemented. Kentucky commits to implementing 
necessary controls as expeditiously as possible, but no later than 12 
months from the conclusion of the most recent ozone season (October 
31).
    Kentucky refers to the second-tier response as an ``action level 
response.'' The action level trigger is the occurrence of a three-year 
average of the fourth highest monitored value of 0.071 ppm or greater 
(i.e., a violation of the 2015 ozone NAAQS). For an action level 
response, Kentucky commits to determining additional control measures 
needed to assure future attainment of the 2015 ozone NAAQS. This will 
be done in conjunction with the metropolitan planning organization or 
regional council of governments, and appropriate contingency measures 
will be implemented within 24 months of a triggered violation.
    Kentucky states that potential contingency measures may be chosen 
from the following list; however, the Commonwealth and the District 
reserve the right to implement other contingency measures if new 
control programs should be developed and deemed more advantageous for 
the Area:
     Implementation of a program to require additional emission 
reductions on stationary sources, including RACT for point sources of 
VOC and NOX, and specifically the adoption of new and 
revised RACT rules based on Groups II, III, and IV CTGs;
     Implementation of a program to enhance inspection of 
stationary sources;
     Implementation of fuel programs, including incentives for 
alternative fuels;
     Restriction of certain roads or lanes to, or construction 
of such roads or lanes for use by, passenger buses or high-occupancy 
vehicles;
     Trip-reduction ordinances;
     Employer-based transportation management plans, including 
incentives;
     Programs for new construction and major reconstructions of 
paths or tracks for use by pedestrians or by non-motorized vehicles 
when economically feasible and in the public interest;
     Implementation of a modern vehicle inspection/maintenance 
program;
     Implementation of diesel retrofit programs, including 
incentives for performing retrofits for fleet vehicle operations; and
     Additional engine idling reduction programs.
    EPA preliminarily finds that the maintenance plan adequately 
provides the five basic required components of a maintenance plan: the 
attainment emissions inventory, maintenance demonstration, monitoring 
plan, verification of continued attainment, and a contingency plan. 
Therefore, EPA proposes to find that the maintenance plan SIP revision 
submitted by Kentucky for the Louisville, KY Area meets the 
requirements of section 175A of the CAA and is approvable.

VI. EPA's Analysis of Kentucky's Proposed NOX and VOC MVEBs

    Under section 176(c) of the CAA, new transportation plans, 
programs, and projects, such as the construction of new highways, must 
``conform'' to (i.e., be consistent with) the part of the state's air 
quality plan that addresses pollution from cars and trucks. Conformity 
to the SIP means that transportation activities will not cause new air 
quality violations, worsen existing violations, or delay timely 
attainment of the NAAQS or any interim milestones. If a transportation 
plan does not conform, most new projects that would expand the capacity 
of roadways cannot go forward. Regulations at 40 CFR part 93 set forth 
EPA policy, criteria, and procedures for demonstrating and assuring 
conformity of such transportation activities to a SIP. The regional 
emissions analysis is one, but not the only, requirement for

[[Page 23609]]

implementing transportation conformity. Transportation conformity is a 
requirement for nonattainment and maintenance areas. Maintenance areas 
are areas that were previously designated as nonattainment for a 
particular NAAQS but have since been redesignated to attainment with an 
approved maintenance plan for that NAAQS.
    Under the CAA, states are required to submit at various times 
control strategy SIPs and maintenance plans for nonattainment areas. 
These control strategy SIPs (including reasonable further progress and 
attainment demonstration requirements) and maintenance plans create 
MVEBs for criteria pollutants and/or their precursors to address 
pollution from cars and trucks. Per 40 CFR part 93, a MVEB must be 
established for the last year of the maintenance plan. A state may 
adopt MVEBs for other years as well. The MVEB is the portion of the 
total allowable emissions in the maintenance demonstration that is 
allocated to highway and transit vehicle use and emissions. See 40 CFR 
93.101. 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. 
See 58 FR 62188. The preamble also describes how to establish the MVEB 
in the SIP and how to revise the MVEB.
    After interagency consultation with the transportation partners for 
the Louisville, KY-IN Area, MVEBs for NOX and VOC for that 
area were developed. Kentucky developed these MVEBs for the last year 
of the maintenance plan (2035) and for the interim year (2019). Because 
the interim MVEB year of 2019 is also the base year for the maintenance 
plan inventory, there is no safety margin; therefore, no adjustments 
were made to the MVEBs for 2019. The 2035 MVEBs reflect the total 
projected on-road emissions for 2035, plus an allocation from the 
available NOX and VOC safety margins. Under 40 CFR 93.101, 
the term ``safety margin'' is the difference between the attainment 
level (from all sources) and the projected level of emissions (from all 
sources) in the maintenance plan. The safety margin can be allocated to 
the transportation sector; however, the total emissions must remain 
below the attainment level. The NOX and VOC MVEBs and 
allocation from the safety margin were developed in consultation with 
the transportation partners and were added to account for uncertainties 
in population growth, changes in model vehicle miles traveled, and new 
emission factor models. The NOX and VOC MVEBs for the Area 
are identified in Table 5, below.

            Table 5--Louisville, KY-IN Area NOX and VOC MVEBs
                                 [tpsd]
------------------------------------------------------------------------
                                                          2019     2035
------------------------------------------------------------------------
NOX On-Road Emissions.................................    33.03    14.20
NOX Safety Margin Allocated to MVEB...................  .......     2.98
    NOX MVEB..........................................    33.03    17.18
VOC On-Road Emissions.................................    13.65     4.68
VOC Safety Margin Allocated to MVEB...................  .......     0.83
    VOC MVEB..........................................    13.65     5.51
------------------------------------------------------------------------

    Kentucky, in consultation with the transportation partners for the 
Louisville, KY-IN Area chose to allocate a portion of the available 
safety margin to the 2035 NOX and VOC MVEBs for the Area 
after consideration of continued air quality improvements, known future 
motor vehicle and fuels controls, projected fleet turnover, expected 
future growth, possible future regulation, and model uncertainty. 
Kentucky allocated 2.98 tpsd of the NOX safety margin to the 
2035 NOX MVEB and 0.83 tpsd of the VOC safety margin to the 
2035 VOC MVEB.\31\ The remaining safety margins for 2035 are 30.17 tpsd 
and 23.18 tpsd for NOX and VOC, respectively.
---------------------------------------------------------------------------

    \31\ The safety margins and safety margin allocations are based 
on the most recent information from the TDM designed by KIPDA and 
data from EPA MOVES3 (see page 34 of the SIP submittal). The final 
safety margins are roughly 20% of projected 2035 NOX 
emissions and 18% of projected VOC emissions.
---------------------------------------------------------------------------

    Through this proposed rulemaking, EPA is proposing to approve the 
MVEBs for NOX and VOC for years 2019 and 2035 for the Area 
because EPA has determined that the Area maintains the 2015 8-hour 
ozone NAAQS with the emissions at the levels of the budgets. If the 
MVEBs for the Area are approved or found adequate (whichever comes 
first), they must be used for future conformity determinations.

VII. EPA's Adequacy Determination for the Proposed NOX and VOC MVEBs

    When reviewing submitted ``control strategy'' SIPs or maintenance 
plans containing MVEBs, EPA may affirmatively find the MVEB contained 
therein adequate for use in determining transportation conformity. Once 
EPA affirmatively finds the submitted MVEB is adequate for 
transportation conformity purposes, that MVEB must be used by state and 
federal agencies in determining whether proposed transportation 
projects conform to the SIP as required by section 176(c) of the CAA.
    EPA's substantive criteria for determining adequacy of a MVEB are 
set out in 40 CFR 93.118(e)(4). The process for determining adequacy 
consists of three basic steps: public notification of a SIP submission, 
a public comment period, and EPA's adequacy determination. This process 
for determining the adequacy of submitted MVEBs for transportation 
conformity purposes was initially outlined in EPA's May 14, 1999, 
guidance, ``Conformity Guidance on Implementation of March 2, 1999, 
Conformity Court Decision.'' EPA adopted regulations to codify the 
adequacy process in the Transportation Conformity Rule Amendments for 
in an action titled ``New 8-Hour Ozone and PM2.5 National 
Ambient Air Quality Standards and Miscellaneous Revisions for Existing 
Areas; Transportation Conformity Rule Amendments--Response to Court 
Decision and Additional Rule Change,'' on July 1, 2004. See 69 FR 
40004. Additional information on the adequacy process for 
transportation conformity purpose is available in the proposed rule 
titled ``Transportation Conformity Rule Amendments: Response to Court 
Decision and Additional Rule Changes.'' See 68 FR 38974, 38984 (June 
30, 2003).
    As discussed earlier, Kentucky's maintenance plan includes 
NOX and VOC MVEBs for the Louisville, KY-IN Area for the 
interim and base year 2019 and for 2035, the last year of the 
maintenance plan. EPA reviewed the NOX and VOC MVEBs through 
the adequacy process described in Section I.

[[Page 23610]]

EPA intends to make its determination on the adequacy of the 2019 and 
2035 MVEBs for the Area for transportation conformity purposes in the 
near future by completing the adequacy process that was started on 
September 14, 2022.\32\ If EPA finds the 2019 and 2035 MVEBs adequate 
or approves them, the new MVEBs for NOX and VOC must be used 
for future transportation conformity determinations. For required 
regional emissions analysis years that involve 2019 through 2034, the 
2019 MVEBs will be used, and for years 2035 and beyond, the applicable 
budgets will be the new 2035 MVEBs established in the maintenance plan.
---------------------------------------------------------------------------

    \32\ As discussed above, comments were due on October 14, 2022. 
See https://www.epa.gov/state-and-local-transportation/state-implementation-plans-sip-submissions-currently-under-epa.
---------------------------------------------------------------------------

VIII. Effect of EPA's Proposed Actions

    EPA's proposed actions establish the basis upon which EPA may take 
final action on the issues being proposed for approval. Approval of 
Kentucky's redesignation request would change the legal designation of 
Bullitt, Jefferson, and Oldham Counties, found at 40 CFR part 81, from 
nonattainment to attainment for the 2015 8-hour ozone NAAQS. Approval 
of Kentucky's associated SIP revision would also incorporate a plan for 
maintaining the 2015 8-hour ozone NAAQS in the Area through 2035 into 
the Kentucky SIP. The maintenance plan establishes NOX and 
VOC MVEBs for 2019 and 2035 for the Louisville KY-IN Area and includes 
contingency measures to remedy any future violations of the 2015 8-hour 
ozone NAAQS and procedures for evaluating potential violations.

IX. Proposed Actions

    EPA is proposing to: (1) approve the maintenance plan for the 
Louisville, KY Area, including the NOX and VOC MVEBs for 
2019 and 2035, and incorporate it into the Kentucky SIP, and (2) 
approve Kentucky's redesignation request for the 2015 8-hour ozone 
NAAQS for the Area. Further, as part of this proposed action, EPA is 
also describing the status of its adequacy determination for the 
NOX and VOC MVEBs for the 2019 and 2035 in accordance with 
40 CFR 93.118(f)(1). Within 24 months from the effective date of EPA's 
adequacy determination for the MVEBs or the effective date for the 
final rule for this action, whichever is earlier, the transportation 
partners will need to demonstrate conformity to the new NOX 
and VOC MVEBs pursuant to 40 CFR 93.104(e)(3).
    If finalized, approval of the redesignation request would change 
the official 2015 8-hour ozone NAAQS designation of Bullitt, Jefferson, 
and Oldham Counties in Kentucky from nonattainment to attainment, as 
found at 40 CFR part 81.

X. 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 Act and applicable Federal regulations. See 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. 
These actions merely propose to approve state law as meeting Federal 
requirements and do not impose additional requirements beyond those 
imposed by state law. For that reason, these proposed actions:
     Are not significant regulatory actions 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);
     Do not impose an information collection burdens under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Are 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.);
     Do not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Do not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Are not economically significant regulatory actions based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Are not significant regulatory actions subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001); and
     Are not subject to requirements of Section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because application of those requirements would be inconsistent 
with the CAA.
    In addition, the SIP is not approved to apply on any Indian 
reservation land or in any other area where EPA or an Indian tribe has 
demonstrated that a tribe has jurisdiction. In those areas of Indian 
country, the rules do not have tribal implications as specified by 
Executive Order 13175 (65 FR 67249, November 9, 2000).
    Executive Order 12898 (Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations, 59 FR 7629, 
Feb. 16, 1994) directs Federal agencies to identify and address 
``disproportionately high and adverse human health or environmental 
effects'' of their actions on minority populations and low-income 
populations to the greatest extent practicable and permitted by law. 
EPA defines environmental justice (EJ) as ``the fair treatment and 
meaningful involvement of all people regardless of race, color, 
national origin, or income with respect to the development, 
implementation, and enforcement of environmental laws, regulations, and 
policies.'' EPA further defines the term fair treatment to mean that 
``no group of people should bear a disproportionate burden of 
environmental harms and risks, including those resulting from the 
negative environmental consequences of industrial, governmental, and 
commercial operations or programs and policies.''
    The Cabinet and District did not evaluate EJ considerations as part 
of its redesignation request or SIP submittal; the CAA and applicable 
implementing regulations neither prohibit nor require such an 
evaluation. EPA did not perform an EJ analysis and did not consider EJ 
as part of Kentucky's redesignation request or SIP submittal in these 
actions. Consideration of EJ is not required as part of these actions, 
and there is no information in the record inconsistent with the stated 
goal of E.O. 12898 of achieving EJ for people of color, low-income 
populations, and Indigenous peoples.

List of Subjects

 40 CFR Part 52

    Environmental protection, Air pollution control, Carbon monoxide, 
Incorporation by reference, Intergovernmental relations, Nitrogen 
dioxide, Ozone, Reporting and recordkeeping requirements, Volatile 
organic compounds.

[[Page 23611]]

40 CFR Part 81

    Environmental protection, Air pollution control, National parks, 
Wilderness areas.

    Authority: 42 U.S.C. 7401 et seq.

    Dated: April 11, 2023.
Daniel Blackman,
Regional Administrator, Region 4.
[FR Doc. 2023-08017 Filed 4-17-23; 8:45 am]
BILLING CODE 6560-50-P