Document ID: EPA-R07-OAR-2017-0349-0001
Agency: epa
Document Type: Proposed Rule
Title: Air Quality State Implementation Plans; Approvals and Promulgations: Redesignation of Missouri Portion of St. Louis-St. Charles-Farmington, MO-IL 2008 Ozone Area to Attainment
Posted Date: 2018-06-25T04:00Z

[Federal Register Volume 83, Number 122 (Monday, June 25, 2018)]
[Proposed Rules]
[Pages 29486-29499]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-13442]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R07-OAR-2017-0349; FRL-9979-84--Region 7]

Approval of Missouri Air Quality Implementation Plans; 
Redesignation of the Missouri Portion of the St. Louis-St. Charles-
Farmington, MO-IL 2008 Ozone Area to Attainment

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
approve a request from the Missouri Department of Natural Resources 
(MDNR) to redesignate the Missouri portion of the St. Louis-St. 
Charles-Farmington, MO-IL nonattainment area (``St. Louis area'' or 
``area'') to attainment for the 2008 ozone National Ambient Air Quality 
Standard (NAAQS). MDNR submitted this request on September 12, 2016, 
with a supplemental submission on February 16, 2018, to include a 
revised motor vehicle emissions budget. EPA is proposing this action 
because the request meets the statutory requirements for redesignation 
under the Clean Air Act (CAA). As part of this action, EPA is also 
proposing to approve, as a revision to the Missouri State 
Implementation Plan (SIP), the state's plan for maintaining the 2008 8-
hour ozone NAAQS through 2030. Finally, EPA finds adequate and is 
proposing to approve, as a SIP revision, the State's 2030 volatile 
organic compound (VOC) and oxides of nitrogen (NOX) Motor 
Vehicle Emission Budgets (MVEBs) for the Missouri portion of the St. 
Louis area. EPA addressed the Illinois portion of the St. Louis area in 
a separate rulemaking action on March 1, 2018. 83 FR 8756.

DATES: Comments must be received on or before July 25, 2018.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R07-
OAR-2017-0349, to https://www.regulations.gov. Follow the online 
instructions for submitting comments. Once submitted, comments cannot 
be edited or removed from Regulations.gov. The EPA may publish any 
comment received to its public docket. Do not submit electronically any 
information

[[Page 29487]]

you consider to be Confidential Business Information (CBI) or other 
information whose disclosure is restricted by statute. Multimedia 
submissions (audio, video, etc.) must be accompanied by a written 
comment. The written comment is considered the official comment and 
should include discussion of all points you wish to make. The EPA will 
generally not consider comments or comment contents located outside of 
the primary submission (i.e. on the web, cloud, or other file sharing 
system). For additional submission methods, the full EPA public comment 
policy, information about CBI or multimedia submissions, and general 
guidance on making effective comments, please visit https://www2.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: Lachala Kemp, Environmental Protection 
Agency, Air Planning and Development Branch, 11201 Renner Boulevard, 
Lenexa, Kansas 66219 at (913) 551-7214, or by email at 
[email protected].

SUPPLEMENTARY INFORMATION: Throughout this document ``we,'' ``us,'' and 
``our'' refer to EPA. This section provides additional information by 
addressing the following:

Table of Contents

I. What is being addressed in this document?
II. Background Information
III. What are the criteria for redesignation?
IV. What is EPA's analysis of Missouri's redesignation request?
    A. Criteria (1)--The St. Louis Area Has Attained the 2008 8-Hour 
Ozone NAAQS
    B. Criteria (2)--Missouri Has a Fully Approved SIP Under Section 
110(k) for the St. Louis Area; and Criteria (5) Missouri Has Met All 
Applicable Requirements for the St. Louis Area of Section 110 and 
Part D of the CAA
    C. Criteria (3)--The Air Quality Improvement in the St. Louis 
Area Is Due to Permanent and Enforceable Emission Reductions
    D. Criteria (4)--The Area Has a Fully Approvable Ozone 
Maintenance Plan Pursant to Section 175 of the CAA
V. Has the State adopted approvable motor vehicle emission budgets?
    A. Motor Vehicle Emission Budgets
    B. What is the status of the EPA's adequacy determination for 
the proposed VOC and NOX MVEBs for the St. Louis area?
    C. What is a safety margin?
VI. Proposed Action
VII. Statutory and Executive Order Reviews

I. What is being addressed in this document?

    EPA is proposing to approve MDNR's request to change the 
designation of the Missouri portion of the St. Louis area from 
nonattainment to attainment for the 2008 ozone NAAQS, based on quality-
assured and certified data monitoring data for 2013-2015, and that the 
Missouri portion of the St. Louis area has met the requirements for 
redesignation under section 107(d)(3)(E) of the CAA.
    EPA is also proposing to approve the state's maintenance plan as a 
revision to the Missouri SIP; the maintenance plan is designed to keep 
the Missouri portion of the St. Louis area in attainment of the 2008 
ozone NAAQS through 2030.
    Finally, EPA finds adequate and is proposing to approve into the 
SIP the newly-established 2030 MVEBs for the area. The adequacy comment 
period for the MVEBs began on April 10, 2018, with EPA's posting of the 
availability of Missouri's submittal on EPA's Adequacy website (at 
https://www.epa.gov/state-and-local-transportation/adequacy-review-state-implementation-plan-sip-submissions-conformity). The adequacy 
comment period for these MVEBs ended on May 10, 2018. EPA did not 
receive any adverse comments on this submittal during the adequacy 
comment period. In a letter dated May 15, 2018, EPA informed Missouri 
that the 2030 MVEBs are adequate for use in transportation conformity 
analyses. Please see section V.B. of this rulemaking, ``What is the 
status of EPA's adequacy determination for the proposed VOC and 
NOX MVEBs for the St. Louis area?'' for further explanation 
of this process.

II. Background Information

    EPA has determined that ground-level ozone is detrimental to human 
health. On March 12, 2008, EPA promulgated a revised 8-hour ozone NAAQS 
of 0.075 parts per million (ppm). See 73 FR 16436 (March 27, 2008). 
Under EPA's regulations at 40 CFR part 50, the 2008 8-hour ozone NAAQS 
is attained when the three-year average of the annual fourth highest 
daily maximum 8-hour average concentration is equal to or less than 
0.075 ppm at all of the ozone monitoring sites in the area. See 40 CFR 
50.15 and appendix P to 40 CFR part 50.
    Upon promulgation of a new or revised NAAQS, section 107(d)(1)(B) 
of the CAA requires EPA to designate as nonattainment any areas that 
are violating the NAAQS based on the most recent three years of quality 
assured ozone monitoring data. The St. Louis area was designated as a 
marginal nonattainment area for the 2008 ozone NAAQS on May 21, 2012 
(77 FR 30088); the designation became effective on July 20, 2012.
    In a final implementation rule for the 2008 ozone NAAQS (SIP 
Requirements Rule),\1\ EPA established ozone standard attainment dates 
based on table 1 of CAA section 181(a). For the areas classified as 
marginal nonattainment, this established an attainment date three years 
after the July 20, 2012 effective date.
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    \1\ This rule, titled ``Implementation of the 2008 National 
Ambient Air Quality Standards for Ozone: State Implementation Plan 
Requirements,'' published on March 6, 2015. 80 FR 12264. The rule 
addresses nonattainment area SIP requirements for the 2008 ozone 
NAAQS, including requirements pertaining to attainment 
demonstrations, reasonable further progress (RFP), reasonably 
available control technology (RACT), reasonably available control 
measures (RACM), new source review (NSR), emission inventories, and 
the timing requirements for SIP submissions and compliance with 
emission control measures in the SIP. This rule also addresses the 
revocation of the 1997 ozone NAAQS and the antibacksliding 
requirements that apply when the 1997 ozone NAAQS is revoked.
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    CAA section 181(b)(2) requires EPA to determine, based on an area's 
ozone design value as of the area's attainment deadline, whether the 
area has attained the ozone standard by that date. The statute provides 
a mechanism by which states that meet certain criteria may request, and 
be granted by the Administrator, a one year extension of an area's 
attainment deadline. On May 4, 2016, based on EPA's evaluation and 
determination that the areas met the criteria of CAA section 181(a)(5), 
EPA granted the St. Louis area a one year extension of the marginal 
area attainment date; the revised attainment date became July 20, 2016. 
81 FR 26697.
    On June 27, 2016, in accordance with CAA section 181(b)(2)(A) and 
the provisions of the SIP Requirements Rule, EPA determined that the 
St. Louis area attained the 2008 8-hour ozone standard by its July 20, 
2016, attainment date. 81 FR 41444. EPA's determination was based upon 
three years of complete, quality assured and certified data for the 
2013-2015 time period.
    On September 12, 2016, with a supplemental revision on February 16, 
2018, Missouri submitted to EPA a request to redesignate the Missouri 
portion of the St. Louis area, to attainment for the 2008 ozone NAAQS, 
and to approve the maintenance plan for that area, including the 2030 
MVEBs, as a revision to the SIP.

III. What are the criteria for redesignation?

    Section 107(d)(3)(E) of the CAA allows redesignation of a 
nonattainment area to attainment of the NAAQS provided that: (1) The 
Administrator determines that the area has attained the NAAQS; (2) the 
Administrator has fully approved the applicable implementation plan for 
the area under section 110(k) of the CAA; (3) the

[[Page 29488]]

Administrator determines that the improvement in air quality is due to 
permanent and enforceable reductions in emissions resulting from 
implementation of the applicable SIP, applicable Federal air pollutant 
control regulations, and other permanent and enforceable emission 
reductions; (4) the Administrator has fully approved a maintenance plan 
for the area as meeting the requirements of section 175A of the CAA; 
and (5) the state containing the area has met all requirements 
applicable to the area for the purposes of redesignation under section 
110 and part D of the CAA.
    On April 16, 1992, EPA provided guidance on redesignations in the 
General Preamble for the Implementation of Title I of the CAA 
Amendments of 1990 (57 FR 13498) and supplemented this guidance on 
April 28, 1992 (57 FR 18070). EPA has provided further guidance on 
processing redesignation requests in the following documents:
    1. ``Ozone and Carbon Monoxide Design Value Calculations,'' 
Memorandum from Bill Laxton, Director, Technical Support Division, June 
18, 1990;
    2. ``Maintenance Plans for Redesignation of Ozone and Carbon 
Monoxide Nonattainment Areas,'' Memorandum from G.T. Helms, Chief, 
Ozone/Carbon Monoxide Programs Branch, April 30, 1992;
    3. ``Contingency Measures for Ozone and Carbon Monoxide (CO) 
Redesignations,'' Memorandum from G.T. Helms, Chief, Ozone/Carbon 
Monoxide Programs Branch, June 1, 1992;
    4. ``Procedures for Processing Requests to Redesignate Areas to 
Attainment,'' Memorandum from John Calcagni, Director, Air Quality 
Management Division, September 4, 1992 (the ``Calcagni Memorandum'');
    5. ``State Implementation Plan (SIP) Actions Submitted in Response 
to Clean Air Act (CAA) Deadlines,'' Memorandum from John Calcagni, 
Director, Air Quality Management Division, October 28, 1992;
    6. ``Technical Support Documents (TSDs) for Redesignation of Ozone 
and Carbon Monoxide (CO) Nonattainment Areas,'' Memorandum from G.T. 
Helms, Chief, Ozone/Carbon Monoxide Programs Branch, August 17, 1993;
    7. ``State Implementation Plan (SIP) Requirements for Areas 
Submitting Requests for Redesignation to Attainment of the Ozone and 
Carbon Monoxide (CO) National Ambient Air Quality Standards (NAAQS) On 
or After November 15, 1992,'' Memorandum from Michael H. Shapiro, 
Acting Assistant Administrator for Air and Radiation, September 17, 
1993;
    8. ``Use of Actual Emissions in Maintenance Demonstrations for 
Ozone and CO Nonattainment Areas,'' Memorandum from D. Kent Berry, 
Acting Director, Air Quality Management Division, November 30, 1993;
    9. ``Part D New Source Review (part D NSR) Requirements for Areas 
Requesting Redesignation to Attainment,'' Memorandum from Mary D. 
Nichols, Assistant Administrator for Air and Radiation, October 14, 
1994; and
    10. ``Reasonable Further Progress, Attainment Demonstration, and 
Related Requirements for Ozone Nonattainment Areas Meeting the Ozone 
National Ambient Air Quality Standard,'' Memorandum from John S. Seitz, 
Director, Office of Air Quality Planning and Standards, May 10, 1995.

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

A. Criteria (1)--The St. Louis Area Has Attained the 2008-Hour Ozone 
NAAQS

    For redesignation of a nonattainment area to attainment, the CAA 
section 107(d)(3)(E)(i) requires EPA to determine that the area has 
attained the applicable NAAQS. An area is attaining the 2008 ozone 
NAAQS if it meets the 2008 ozone NAAQS, as determined in accordance 
with 40 CFR 50.15 and appendix P of part 50, based on three complete, 
consecutive calendar years of quality assured air quality data for all 
monitoring sites in the area. To attain the NAAQS, the three-year 
average of the annual fourth-highest daily maximum 8-hour average ozone 
concentrations (ozone design values) at each monitor must not exceed 
0.075 ppm. The air quality data must be collected and quality-assured 
in accordance with 40 CFR part 58 and recorded in EPA's Air Quality 
System (AQS). Ambient air quality monitoring data for the three year 
period must also meet data completeness requirements. An ozone design 
value is valid if daily maximum 8-hour average concentrations are 
available for at least 90 percent of the days within the ozone 
monitoring seasons,\2\ on average, for the three-year period, with a 
minimum data completeness of 75 percent during the ozone monitoring 
season of any year during the three year period. See section 2.3 of 
appendix P to 40 CFR part 50.
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    \2\ The ozone season is defined by state in 40 CFR 58 appendix 
D. The ozone season for the St. Louis area runs from March-October.
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    On June 27, 2016, in accordance with CAA section 181(b)(2)(A) and 
the provisions of the SIP Requirements Rule, EPA determined that the 
St. Louis area attained the 2008 ozone NAAQS by its July 20, 2016, 
attainment date. See 81 FR 41444. EPA's determination was based upon 
three years of complete, quality assured and certified data that had 
been recorded in AQS for the 2013-2015 time period. The data 
demonstrated that the St. Louis area is attaining the 2008 ozone NAAQS. 
The annual fourth-highest 8-hour ozone concentrations and the three-
year average of these concentrations (monitoring site ozone design 
values) for each monitoring site are summarized in table 1.

 Table 1--Annual 4th Highest Daily Maximum 8-Hour Ozone Concentrations and 3-Year Averages for the St. Louis-St.
                                         Charles-Farmington, MO-IL Area
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                                                                4th Highest values                   2013-2015
            County               Monitoring site ------------------------------------------------  Design value
                                      name          2013 (ppm)      2014 (ppm)      2015 (ppm)         (ppm)
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St. Charles, MO...............  Orchard Farm....           0.071           0.072           0.066           0.069
St. Charles, MO...............  West Alton......           0.071           0.072           0.070           0.071
St. Louis City, MO............  Blair Street....           0.066           0.066           0.063           0.065
St. Louis, MO.................  Maryland Heights           0.070           0.072           0.069           0.070
St. Louis, MO.................  Pacific.........           0.067           0.065           0.065           0.065
Jefferson, MO.................  Arnold West.....           0.069           0.072           0.069           0.070
Madison, IL...................  Alhambra........           0.071           0.068           0.067           0.068

[[Page 29489]]

 
Madison, IL...................  Alton...........           0.072           0.072           0.069           0.071
Madison, IL...................  Maryville.......           0.075           0.070           0.064           0.069
Madison, IL...................  Wood River......           0.069           0.070           0.069           0.069
St. Clair, IL.................  East St. Louis..           0.066           0.067           0.066           0.066
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    The most recent certified, quality assured data for 2017 indicates 
that the area continues to attain the 2008 ozone NAAQS. If the design 
value of a monitoring site in the area exceeds the NAAQS after 
proposal, but before final approval of the redesignation, EPA will not 
take final action to approve the redesignation of the St. Louis area to 
attainment.
    The three-year ozone design value for 2013-2015 is 0.071 ppm,\3\ 
which meets the 2008 ozone NAAQS. Therefore, in this action, EPA 
proposes to determine that the St. Louis area is attaining the 2008 
ozone NAAQS.
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    \3\ The ozone design value for the monitor with the highest 
three-year averaged concentration.
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B. Criteria (2)--Missouri Has a Fully Approved SIP Under Section 110(k) 
for the St. Louis Area; and Criteria (5)--Missouri Has Met All 
Applicable Requirements for the St. Louis Area of Section 110 and Part 
D of the CAA

    As criteria for redesignation of an area from nonattainment to 
attainment of a NAAQS, the CAA requires EPA to determine that the state 
has met all applicable requirements under CAA section 110 and part D of 
title I of the CAA (see section 107(d)(3)(E)(v) of the CAA) and that 
the state has a fully approved SIP under CAA section 110(k) (see 
section 107(d)(3)(E)(ii) of the CAA). EPA proposes to find that 
Missouri has met all currently applicable SIP requirements for purposes 
of redesignation of the St. Louis area to attainment of the 2008 ozone 
standard under section 110 and part D of the CAA in accordance with 
section 107(d)(2)(E)(v). In making these proposed determinations, EPA 
ascertained which CAA requirements are applicable to the St. Louis area 
and the Missouri SIP and, if applicable, whether the required Missouri 
SIP elements are fully approved under section 110(k) and part D of the 
CAA. As discussed more fully below, SIPs must be fully approved only 
with respect to currently applicable requirements of the CAA.\4\
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    \4\ See section 175A(c) of the CAA. See September 4, 1992 
Calcagni Memorandum. See Sierra Club v. EPA, 375 F.3d 537 (7th Cir. 
2004). See also 68 FR 25418 (May 12, 2003, pages 68 FR 25424 and 68 
FR 25427) (redesignation of the St. Louis/East St. Louis area to 
attainment of the 1-hour ozone NAAQS). See also the September 17, 
1993, Michael Shapiro memorandum and 60 FR 12459, 60 FR 12465-60 FR 
12466 (March 7, 1995) (redesignation of Detroit Ann Arbor, Michigan 
to attainment of the 1-hour ozone NAAQS).
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1. Missouri Has Met All Applicable Requirements of Section 110 and Part 
D of the CAA Applicable to the Missouri Portion of the St. Louis Area 
for Purposes of Redesignation
    General SIP Requirements. Section 110(a)(2) of the CAA delineates 
the general requirements for a SIP. Section 110(a)(2) provides that the 
SIP must have been adopted by the state after reasonable public notice 
and hearing, and that, among other things, it must: (1) Include 
enforceable emission limitations and other control measures, means or 
techniques necessary to meet the requirements of the CAA; (2) provide 
for establishment and operation of appropriate devices, methods, 
systems, and procedures necessary to monitor ambient air quality; (3) 
provide for implementation of a source permit program to regulate the 
modification and construction of stationary sources within the areas 
covered by the plan; (4) include provisions for the implementation of 
part C prevention of significant deterioration (PSD) and part D new 
source review (NSR) permit programs; (5) include provisions for 
stationary source emission control measures, monitoring, and reporting; 
(6) include provisions for air quality modeling; and, (7) provide for 
public and local agency participation in planning and emission control 
rule development.
    Section 110(a)(2)(D) of the CAA requires SIPs to contain measures 
to prevent sources in a state from significantly contributing to air 
quality problems in another state. To implement this provision, EPA has 
required certain states to establish programs to address transport of 
certain air pollutants.\5\ However, like many of the 110(a)(2) 
requirements, the section 110(a)(2)(D) SIP requirement is not linked 
with a particular area's ozone designation and classification. EPA 
believes that the SIP requirements linked with the area's ozone 
designation and classification are the relevant measures to evaluate 
when reviewing a redesignation request for the area. The section 
110(a)(2)(D) requirements, where applicable, continue to apply to a 
state regardless of the designation of any one particular area within 
the state. Thus, EPA does not believe these requirements should be 
construed to be applicable requirements for the purposes of 
redesignation.\6\
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    \5\ Nitrogen oxides (NOX) are precursor pollutants to 
ozone formation. On October 27, 1992 (63 FR 57356), EPA issued a 
NOX SIP call requiring 22 states and the District of 
Columbia to reduce emissions of NOX in order to reduce 
the transport of ozone and ozone precursors.
    \6\ See 65 FR 37890 (June 15, 2000), 66 FR 50399 (October 19, 
2001), 68 FR 25418, 68 FR 25426-27 (May 13, 2003).
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    In addition, EPA believes that other section 110 elements are 
neither connected with nonattainment plan submissions, nor linked with 
an area's ozone attainment status and are not applicable requirements 
for purposes of redesignation. The area will still be subject to these 
requirements after the area is redesignated to attainment for the 2008 
ozone NAAQS. The section 110 and part D requirements which are linked 
with a particular area's designation and classification are the 
relevant measures to evaluate when 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.\7\ EPA has reviewed

[[Page 29490]]

Missouri's SIP revision and has concluded that it meets the general SIP 
requirements under section 110 of the CAA to the extent that those 
requirements are applicable for purposes of redesignation. On March 22, 
2018 (83 FR 12496), EPA approved elements of the SIP submitted by 
Missouri to meet the requirements of section 110 for the 2008 ozone 
standard. The requirements of section 110(a)(2), however, are statewide 
requirements that are not linked to the ozone nonattainment status of 
the St. Louis area. Therefore, EPA concludes that these infrastructure 
requirements are not applicable requirements for purposes of review of 
the state's ozone redesignation request.
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    \7\ See Reading, Pennsylvania proposed and final rulemakings, 61 
FR 53174-61 FR 53176 (October 10, 1996) and 62 FR 24826 (May 7, 
1997); Cleveland-Akron-Loraine, Ohio final rulemaking, 61 FR 20458 
(May 7, 1996); and Tampa, Florida final rulemaking, 60 FR 62748 
(December 7, 1995). See also the discussion of this issue in the 
Cincinnati, Ohio ozone redesignation (65 FR 37890, June 19, 2000), 
and the Pittsburgh, Pennsylvania ozone redesignation (66 FR 50399, 
October 19, 2001).
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    Part D Requirements. Section 172(c) of the CAA sets forth the basic 
requirements of air quality plans for states with nonattainment areas 
that are required to submit them pursuant to section 172(b). Subpart 2 
of part D, which includes section 182 of the CAA, establishes specific 
requirements for ozone nonattainment areas depending on the areas' 
nonattainment classifications.
    The Missouri portion of the St. Louis area was classified as 
marginal under subpart 2 for the 2008 ozone NAAQS. As such, the area is 
subject to the subpart 1 requirements contained in section 172(c) and 
section 176. Similarly, the area is subject to the subpart 2 
requirements contained in section 182(a) (marginal nonattainment area 
requirements). A thorough discussion of the requirements contained in 
section 172(c) and 182 can be found in the General Preamble for 
Implementation of title I (57 FR 13498).
    Subpart 1 Section 172 Requirements. As provided in subpart 2, for 
marginal ozone nonattainment areas such as the St. Louis area, the 
specific requirements of section 182(a) apply in lieu of the attainment 
planning requirements that would otherwise apply under section 172(c), 
including the attainment demonstration and reasonably available control 
measures (RACM) under section 172(c)(1), reasonable further progress 
(RFP) under section 172(c)(2), and contingency measures under section 
172(c)(9).\8\
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    \8\ See 42 U.S.C. 7511a(a).
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    Section 172(c)(3) requires submission and approval of a 
comprehensive, accurate and current inventory of actual emissions. This 
requirement is superseded by the inventory requirement in section 
182(a)(1) discussed below.
    Section 172(c)(4) requires the identification and quantification of 
allowable emissions for major new and modified stationary sources in an 
area, and section 172(c)(5) requires source permits for the 
construction and operation of new and modified major stationary sources 
anywhere in the nonattainment area. EPA most recently approved 
Missouri's NSR program on June 4, 2015 (80 FR 31844).\9\ EPA has 
determined that, since PSD requirements will apply after redesignation, 
areas being redesignated need not comply with the requirement that a 
NSR program be approved prior to redesignation, provided that the area 
demonstrates maintenance of the NAAQS without part D NSR. A more 
detailed rationale for this view is described in the Nichols 
Memorandum. See also rulemakings for the Illinois portion of the St. 
Louis Area (77 FR 34819, 77 FR 34826, June 12, 2012); Louisville, 
Kentucky (66 FR 53665, 66 FR 53669, October 23, 2001); Grand Rapids, 
Michigan (61 FR 31831, 61 FR 31834-61 FR 31837, June 21, 1996); 
Cleveland-Akron-Lorain, Ohio (61 FR 20458, 61 FR 20469-61 FR 20470, May 
7, 1996); Detroit, Michigan (60 FR 12459, 61 FR 12467-61 FR 12468, 
March 7, 1995). Missouri has demonstrated that the area will be able to 
maintain the standard without part D NSR in effect; therefore, EPA 
concludes that the state need not have a fully approved part D NSR 
program prior to approval of the redesignation request. Missouri's PSD 
program will become effective in the area upon redesignation to 
attainment.
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    \9\ The ``Marginal Area Plan for the Missouri Portion of the St. 
Louis Nonattainment Area for the 2008 8-Hour Ground Level Ozone 
National Ambient Air Quality Standard'' submitted by the state on 
September 9, 2014 noted that the state's NSR program was approved by 
EPA and that no ``corrections'' needed to be made in the SIP. This 
SIP revision was approved on February 25, 2016 (81 FR 9346).
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    Section 172(c)(6) requires the SIP to contain control measures 
necessary to provide for attainment of the NAAQS. Because attainment 
has been reached, no additional measures are needed to provide for 
attainment.
    Section 172(c)(7) requires the SIP to meet the applicable 
provisions of section 110(a)(2). As noted above, we believe the 
Missouri SIP meets the requirements of section 110(a)(2) for purposes 
of redesignation.
    Subpart 1 Section 176 Conformity Requirements. Section 176(c) of 
the CAA requires states to establish criteria and procedures to ensure 
that Federally supported or funded projects conform to the air quality 
planning goals in the applicable SIP. The requirement to determine 
conformity applies to transportation plans, programs and projects that 
are developed, funded or approved under title 23 of the United States 
Code (U.S.C.) and the Federal Transit Act (transportation conformity) 
as well as to all other Federally supported or funded projects (general 
conformity). State transportation conformity SIP revisions must be 
consistent with Federal conformity regulations relating to 
consultation, enforcement and enforceability that EPA promulgated 
pursuant to its authority under the CAA.
    EPA interprets the conformity SIP requirements as not applying for 
purposes of evaluating a redesignation request under section 107(d) 
because state conformity rules are still required after redesignation 
and Federal conformity rules apply where state conformity rules have 
not been approved.\10\ 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). Nevertheless, Missouri has an 
approved conformity SIP for the St. Louis-St. Charles-Farmington, MO-IL 
area. See 78 FR 53247 (August 29, 2013).
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    \10\ CAA section 176(c)(4)(E) requires states to submit 
revisions to their SIPs to reflect certain Federal criteria and 
procedures for determining transportation conformity. Transportation 
conformity SIPs are different from SIPs requiring the development of 
Motor Vehicle Emission Budgets (MVEBs), such as control strategy 
SIPs and maintenance plans.
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    Section 182(a) Requirements. Section 182(a)(1) requires states to 
submit a comprehensive, accurate, and current inventory of actual 
emissions from sources of volatile organic compounds (VOCs) and 
nitrogen oxides (NOX) emitted within the boundaries of the 
ozone nonattainment area. The state's ``Marginal Area Plan for the 
Missouri Portion of the St. Louis Nonattainment Area for the 2008 8-
Hour Ground Level Ozone National Ambient Air Quality Standard'' 
submitted by the state on September 9, 2014, included a 2011 base year 
emissions inventory for the Missouri portion of the St. Louis area. EPA 
approved this emissions inventory as a revision to the Missouri SIP on 
February 25, 2016 (81 FR 9346).
    Under section 182(a)(2)(A), states with ozone nonattainment areas 
that were designated before 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

[[Page 29491]]

control technology (RACT) rules that were required under section 
172(b)(3) before the 1990 CAA amendments. The St. Louis area is not 
subject to the section 182(a)(2) RACT ``fix up'' requirement for the 
2008 ozone NAAQS because it was designated as nonattainment for this 
standard after the enactment of the 1990 CAA amendments and because 
Missouri complied with this requirement for the St. Louis area under 
the prior 1-hour ozone NAAQS.\11\
---------------------------------------------------------------------------

    \11\ See 65 FR 31482 (June 18, 2000) and 61 FR 10968 (March 18, 
1996).
---------------------------------------------------------------------------

    Section 182(a)(2)(B) requires each state with a marginal ozone 
nonattainment area that implemented or was required to implement a 
vehicle inspection and maintenance (I/M) program before the 1990 CAA 
amendments to submit a SIP revision for an I/M program no less 
stringent than that required prior to the 1990 CAA amendments or 
already in the SIP at the time of the CAA amendments, whichever is more 
stringent. For the purposes of the 2008 ozone standard and the 
consideration of Missouri's redesignation request for this standard, 
the St. Louis area is not subject to the section 182(a)(2)(B) 
requirement because the St. Louis area was designated as nonattainment 
for the 2008 ozone standard after the enactment of the 1990 CAA 
amendments.
    Regarding the source permitting and offset requirements of section 
182(a)(2)(C) and section 182(a)(4), as previously noted, Missouri 
currently has a fully-approved part D NSR program in place. The state's 
``Marginal Area Plan for the Missouri Portion of the St. Louis 
Nonattainment Area for the 2008 8-Hour Ground Level Ozone National 
Ambient Air Quality Standard'' submitted in September 2014, included an 
offset ratio. As noted in the September 2014 SIP revision, the 
requirement for emission offset reductions is part of Missouri's NSR 
program and codified in the state's regulations at 10 CSR 10-
6.060(7)(B)1. The corresponding offset ratio for each ozone area 
classification (i.e. 1.1:1 for Marginal) is found in the Federal code 
at 40 CFR 51.165(a)(3)(9). Thus Missouri has satisfied the CAA section 
182(a)(4) requirement for Marginal Area Plan submissions in 
establishing a Marginal Area emission offset reduction ratio of 1.1:1 
in its NSR program by SIP-approved rule consistent with the 
corresponding Federal code. EPA approved the September 2014 SIP 
revision on February 25, 2016 (81 FR 9346).
    Section 182(a)(3) requires states to submit periodic emission 
inventories and a revision to the SIP to require the owners or 
operators of stationary sources to annually submit emission statements 
documenting actual VOC and NOX emissions. As discussed 
below, Missouri will continue to update its emissions inventory at 
least once every three years. With regard to stationary source emission 
statements, EPA last approved Missouri's emission statement rule on 
March 19, 2015 (80 FR 14312). In MDNR's May 22, 2015 submittal, 
Missouri stated that this approved SIP regulation remains in place and 
remains enforceable for the 2008 ozone standard. The state's ``Marginal 
Area Plan for the Missouri Portion of the St. Louis Nonattainment Area 
for the 2008 8-Hour Ground Level Ozone National Ambient Air Quality 
Standard'' SIP revision submitted in September 2014, noted that SIP 
approved state regulation 10 CSR 10-6.110 Reporting Emission Data, 
Emission Fees, and Process Information requires permitted sources to 
file an annual report on air pollutant emissions to include emissions 
data, process information, and annual emissions fees. EPA approved the 
September 2014 SIP revision on February 25, 2016 (81 FR 9346).
    EPA is proposing to approve that the Missouri portion of the St. 
Louis area has satisfied all applicable requirements for purposes of 
redesignation under section 110 and part D of title I of the CAA.
2. The St. Louis Area Has a Fully Approved SIP for Purposes of 
Redesignation Under Section 110(k) of the CAA
    As discussed above, EPA has fully approved the Missouri SIP for the 
St. Louis area under section 110(k) all requirements applicable for 
purposes of redesignation under the 2008 ozone NAAQS. EPA may rely on 
prior SIP approvals in approving a redesignation request (see the 
Calcagni memorandum at page 3; Southwestern Pennsylvania Growth 
Alliance v. Browner, 144 F.3d 984, 989-90 (6th Cir. 1998); Wall v. EPA, 
265 F.3d 426), plus any additional measures it may approve in 
conjunction with a redesignation action (see 68 FR 25426 (May 12, 2003) 
and citations therein). Missouri has adopted and submitted, and EPA has 
fully approved at various times, provisions addressing the various SIP 
elements applicable for the ozone NAAQS.
    As indicated 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. EPA has approved all part D requirements 
applicable for purposes of this redesignation.

C. Criteria (3)--The Air Quality Improvement in the St. Louis Area Is 
Due to Permanent and Enforceable Emission Reductions

    To support the redesignation of an area from nonattainment to 
attainment, section 107(d)(3)(E)(iii) of the CAA requires EPA to 
determine that the air quality improvement in the area is due to 
permanent and enforceable reductions in emissions resulting from the 
implementation of the SIP and applicable Federal air pollution control 
regulations and other permanent and enforceable emission reductions. 
EPA is proposing to determine that Missouri has demonstrated that the 
observed ozone air quality improvement in the St. Louis area is due to 
permanent and enforceable reductions in VOC and NOX 
emissions resulting from state measures adopted into the SIP and 
Federal measures.
    In making this demonstration, the state has calculated the change 
in emissions between 2011 and 2014. The reduction in emissions and the 
corresponding improvement in air quality over this time period can be 
attributed to a number of regulatory control measures that the St. 
Louis area and upwind areas have implemented in recent years. Based on 
the information summarized below, Missouri has adequately demonstrated 
that the improvement in air quality is due to permanent and enforceable 
emissions reductions.
1. Permanent and Enforceable Emission Controls Implemented
a. Regional NOX Controls
    Clean Air Interstate Rule (CAIR)/Cross State Air Pollution Rule 
(CSAPR)/CSAPR Update. CAIR created regional cap-and-trade programs to 
reduce sulfur dioxide (SO2) and NOX emissions in 
twenty seven eastern states, including Missouri, that contributed to 
downwind nonattainment and maintenance of the 1997 8-hour ozone NAAQS 
and the 1997 fine particulate matter (PM2.5) NAAQS. See 70 
FR 25162 (May 12, 2005). EPA approved Missouri's CAIR regulations into 
the Missouri SIP on December 14, 2007 (72 FR 71073). In 2008, the 
United States Court of Appeals for the District of Columbia Circuit 
(D.C. Circuit) initially vacated CAIR, North Carolina v. EPA, 531 F.3d 
896 (D.C. Cir. 2008), but ultimately remanded the rule to EPA without

[[Page 29492]]

vacatur to preserve the environmental benefits provided by CAIR, North 
Carolina v. EPA, 550 F.3d 1176, 1178 (D.C. Cir. 2008). On August 8, 
2011 (76 FR 48208), acting on the D.C. Circuit's remand, EPA 
promulgated CSAPR to replace CAIR and thus to address the interstate 
transport of emissions contributing to nonattainment and interfering 
with maintenance of the two air quality standards covered by CAIR as 
well as the 2006 PM2.5 NAAQS. CSAPR requires substantial 
reductions of SO2 and NOX emissions from electric 
generating units (EGUs) in 28 states in the Eastern United States.
    The D.C. Circuit's initial vacatur of CSAPR was reversed by the 
United States Supreme Court on April 29, 2014, and the case was 
remanded to the D.C. Circuit to resolve remaining issues in accordance 
with the high court's ruling. EPA v. EME Homer City Generation, L.P., 
134 S. Ct. 1584 (2014).\12\ On remand, the D.C. Circuit affirmed CSAPR 
in most respects, but invalidated without vacating some of the CSAPR 
budgets as to a number of states. EME Homer City Generation, L.P. v. 
EPA, 795 F.3d 118 (D.C. Cir. 2015). This litigation ultimately delayed 
implementation of CSAPR for three years, from January 1, 2012, when 
CSAPR's cap-and-trade programs were originally scheduled to replace the 
CAIR cap-and-trade programs, to January 1, 2015. Thus, the rule's Phase 
2 budgets that were originally promulgated to begin on January 1, 2014, 
began on January 1, 2017.
---------------------------------------------------------------------------

    \12\ EME Homer City Generation, L.P. v. EPA, 696 F. 3d 7, 38 
(D.C. Cir. 2012).
---------------------------------------------------------------------------

    On November 21, 2014, the Administrator signed an action that 
published in the Federal Register on December 3, 2014 (79 FR 71163), 
amending the regulatory text of CSAPR to reflect the Court's October 
23, 2014, order tolling all deadlines in CSAPR by three years, 
including provisions governing the sunsetting of CAIR. CAIR therefore 
sunset at the end of 2014 and was replaced by CSAPR beginning January 
1, 2015, which continue to remain in place. Relative to CAIR, CSAPR 
required similar or greater emission reductions from relevant upwind 
areas starting in 2015 and beyond, and Missouri's emissions budgets 
were not affected by the Court's remand of some of the ozone-season and 
SO2 budgets.
    While the reduction in NOX emissions from the 
implementation of CSAPR will result in lower concentrations of 
transported ozone and ozone precursors entering the St. Louis area 
throughout the maintenance period, EPA is proposing to approve the 
redesignation of the St. Louis area without relying on those measures 
within Missouri as having led to attainment of the 2008 ozone NAAQS or 
contributing to maintenance of that standard because, as noted above, 
CSAPR did not go into effect until January 1, 2015. As a general 
matter, EPA expects that the implementation of CSAPR will preserve the 
reductions achieved by CAIR and result in additional SO2 and 
NOX emission reductions throughout the maintenance period.
    In addition, on October 26, 2016 (81 FR 74504), EPA finalized the 
Cross-State Air Pollution Rule Update for the 2008 Ozone NAAQS (CSAPR 
Update). This new rule replaces the CSAPR rule for purposes of 
transport of ozone pollution with respect to the 2008 ozone NAAQS. The 
finalized rule issued a Federal Implementation Plan (FIP) that 
generally provided updated CSAPR NOX ozone season emission 
budgets for the EGUs within twenty two states in the eastern United 
States, and implements these budgets via modifications to the CSAPR 
NOX ozone season allowance trading program established under 
the original CSAPR. The CSAPR Update rule became effective on December 
27, 2016.
b. Federal and State Emission Control Measures
    Reductions in VOC and NOX emissions have occurred 
statewide and in upwind areas as a result of Federal emission control 
measures, with additional emission reductions expected to occur in the 
future. Federal emission control measures are described below.
    Tier 2 Emission Standards for Vehicles and Gasoline Sulfur 
Standards. On February 10, 2000 (65 FR 6698), EPA promulgated Tier 2 
motor vehicle emission standards and gasoline sulfur control 
requirements. These emission control requirements result in lower VOC 
and NOX emissions from new cars and light duty trucks, 
including sport utility vehicles. With respect to fuels, this rule 
required refiners and importers of gasoline to meet lower standards for 
sulfur in gasoline, which were phased in between 2004 and 2006. By 
2006, refiners were required to meet a 30 ppm average sulfur level, 
with a maximum cap of 80 ppm. This reduction in fuel sulfur content 
ensures the effectiveness of low emission-control technologies. The 
Tier 2 tailpipe standards established in this rule were phased in for 
new vehicles between 2004 and 2009. EPA estimates that, when fully 
implemented, this rule will cut NOX and VOC emissions from 
light-duty vehicles and light-duty trucks by approximately 76 and 28 
percent, respectively. NOX and VOC reductions from medium-
duty passenger vehicles included as part of the Tier 2 vehicle program 
are estimated to be approximately 37,000 and 9,500 tons per year, 
respectively, when fully implemented. In addition, EPA estimates that 
beginning in 2007, a reduction of 30,000 tons per year of 
NOX will result from the benefits of sulfur control on 
heavy-duty gasoline vehicles. Some of these emission reductions 
occurred by the attainment years and additional emission reductions 
will occur throughout the maintenance period, as older vehicles are 
replaced with newer, compliant model years.
    Heavy-Duty Diesel Engine Rules. In July 2000, EPA issued a rule for 
on-highway heavy-duty diesel engines that includes standards limiting 
the sulfur content of diesel fuel. Emissions standards for 
NOX, VOC and PM were phased in between model years 2007 and 
2010. In addition, the rule reduced the highway diesel fuel sulfur 
content to 15 parts per million by 2007, leading to additional 
reductions in combustion NOX and VOC emissions. EPA has 
estimated future year emission reductions due to implementation of this 
rulemaking. Nationally, EPA estimated that 2015 NOX and VOC 
emissions would decrease by 1,260,000 tons and 54,000 tons, 
respectively. Nationally, EPA estimated that 2030 NOX and 
VOC emissions will decrease by 2,570,000 tons and 115,000 tons, 
respectively.
    Nonroad Diesel Rule. On June 29, 2004 (69 FR 38958), EPA issued a 
rule adopting emissions standards for nonroad diesel engines and sulfur 
reductions in nonroad diesel fuel. This rule applies to diesel engines 
used primarily in construction, agricultural, and industrial 
applications. The rule is being phased between 2008 through 2015, and 
when fully implemented will reduce emissions of NOX, VOC, 
particulate matter, and carbon monoxide from these engines. It is 
estimated that compliance with this rule will cut NOX 
emissions from these nonroad diesel engines by approximately 90 percent 
nationwide.
    Nonroad Spark-Ignition Engines and Recreational Engine Standards. 
On November 8, 2002 (67 FR 68242), EPA adopted emission standards for 
large spark-ignition engines such as those used in forklifts and 
airport ground-service equipment; recreational vehicles such as off-
highway motorcycles, all-terrain vehicles, and snowmobiles; and 
recreational marine diesel engines. These emission standards are phased 
in

[[Page 29493]]

from model year 2004 through 2012. When fully implemented, EPA 
estimates an overall 72 percent reduction in VOC emissions from these 
engines and an 80 percent reduction in NOX emissions. Some 
of these emission reductions occurred by the attainment years and 
additional emission reductions will occur throughout the maintenance 
period.
    National Emission Standards for Hazardous Air Pollutants (NESHAP) 
for Reciprocating Internal Combustion Engines. On March 3, 2010 (75 FR 
9684), EPA issued a rule to reduce hazardous air pollutants from 
existing diesel powered stationary reciprocating internal combustion 
engines, also known as compression ignition engines. Amendments to this 
rule were finalized on January 14, 2013 (78 FR 6674). EPA estimated 
that when this rule was fully implemented in 2013, NOX and 
VOC emissions from these engines would be reduced by approximately 
9,600 and 36,000 tons per year, respectively.
    Category 3 Marine Diesel Engine Standards. On April 30, 2010 (75 FR 
22896), EPA issued emission standards for marine compression-ignition 
engines at or above 30 liters per cylinder. Tier 2 emission standards 
apply beginning in 2011, and are expected to result in a 15 to 25 
percent reduction in NOX emissions from these engines. Final 
Tier 3 emission standards apply beginning in 2016 and are expected to 
result in approximately an 80 percent reduction in NOX from 
these engines. Some of these emission reductions occurred by the 
attainment years and additional emission reductions will occur 
throughout the maintenance period.
c. Control Measures Specific to the St. Louis Area
    Gateway Vehicle Inspection Program. On March 3, 2015 (80 FR 11323), 
EPA approved Missouri's Gateway Vehicle Inspection Program which is 
found in the Missouri Code of State Regulation (CSR) at 10 CSR 5.381. 
This regulation is permanent and enforceable, and will result in 
continued significant reductions in both NOX and VOC 
emissions from 2014 to 2030.
2. Emission Reductions
    Missouri is using a 2011 emissions inventory as the nonattainment 
base year. Area, nonroad mobile, onroad mobile, and point source 
emissions (EGUs and non-EGUs) were collected from the Ozone NAAQS 
Implementation Modeling platform (2011v6.1). MDNR also provided an 
emissions inventory for wildfires (Event) and biogenic sources. For 
2011, this represents actual data Missouri reported to EPA for the 2011 
National Emissions Inventory (NEI). Because emissions from state 
inventory databases, the NEI, and the Ozone NAAQS Emissions Modeling 
platform are annual totals, tons per summer day (tpd) were derived 
according to EPA's guidance document ``Temporal Allocation of Annual 
Emissions Using EMCH Temporal Profiles'' dated April 29, 2002, using 
the temporal allocation references accompanying the 2011v6.1 modeling 
inventory files.
    For the attainment inventory, Missouri used 2014, one of the years 
the St. Louis area monitored attainment of the 2008 ozone standard. 
Because the 2014 NEI inventory was not available at the time MDNR was 
compiling the redesignation request, the state was unable to use the 
2014 NEI inventory directly. For area, nonroad mobile, wildfire, and 
biogenic sources, 2014 emissions were derived by interpolating between 
2011 and 2018 Ozone NAAQS Emissions Modeling platform inventories. The 
point source sector for the 2014 inventory was developed using actual 
2014 point source emissions reported to the state database, which serve 
as the basis for the point source emissions reported to EPA for the 
NEI. Summer day inventories were derived for these sectors using the 
methodology described above. Finally, onroad mobile source emissions 
were developed using the same methodology described above for the 2011 
inventory.
    Using the inventories described above, Missouri's submittal 
documents changes in VOC and NOX emissions from 2011 to 2014 
for the Missouri portion of the St. Louis area. Emissions data are 
shown in tables 2 through 6.

            Table 2--Missouri Portion of the St. Louis Area NOX Emissions for Nonattainment Year 2011
                                                      [tpd]
----------------------------------------------------------------------------------------------------------------
                     County                            Point           Area           Onroad          Nonroad
----------------------------------------------------------------------------------------------------------------
Franklin........................................           27.75            0.49            7.83            5.72
Jefferson.......................................           16.66            0.62           12.45            3.33
St. Charles.....................................           25.04            0.68           21.04            8.34
St. Louis.......................................           16.74            2.65           66.34           23.85
St. Louis City..................................            4.49            1.16           16.55            6.31
                                                 ---------------------------------------------------------------
    Total.......................................           90.68            5.60          124.21           47.55
----------------------------------------------------------------------------------------------------------------

            Table 3--Missouri Portion of the St. Louis Area VOC Emissions for Nonattainment Year 2011
                                                      [tpd]
----------------------------------------------------------------------------------------------------------------
                     County                            Point           Area           Onroad          Nonroad
----------------------------------------------------------------------------------------------------------------
Franklin........................................            2.52            3.36             2.4            3.31
Jefferson.......................................            1.63            7.48            4.24            3.12
St. Charles.....................................            3.34           11.21            6.73            6.23
St. Louis.......................................             3.5           38.68           20.17           22.99
St. Louis City..................................            3.59           12.04            4.46            3.38
                                                 ---------------------------------------------------------------
    Total.......................................           14.58           72.77           38.00           39.03
----------------------------------------------------------------------------------------------------------------

[[Page 29494]]

             Table 4--Missouri Portion of the St. Louis Area NOX Emissions for Attainment Year 2014
                                                      [tpd]
----------------------------------------------------------------------------------------------------------------
                     County                            Point           Area           Onroad          Nonroad
----------------------------------------------------------------------------------------------------------------
Franklin........................................           21.13            0.46            8.00            5.24
Jefferson.......................................           17.96            0.42           12.87            3.04
St. Charles.....................................           21.05            0.89           19.68            7.40
St. Louis.......................................           16.79            3.77           60.29           17.53
St. Louis City..................................            4.78            0.93           10.92            5.23
                                                 ---------------------------------------------------------------
    Total.......................................           81.71            6.47          111.76           38.44
----------------------------------------------------------------------------------------------------------------

             Table 5--Missouri Portion of the St. Louis Area VOC Emissions for Attainment Year 2014
                                                      [tpd]
----------------------------------------------------------------------------------------------------------------
                     County                            Point           Area           Onroad          Nonroad
----------------------------------------------------------------------------------------------------------------
Franklin........................................            2.08            5.80            2.57            2.91
Jefferson.......................................            1.91            5.44            4.65            2.72
St. Charles.....................................            4.12           11.50            7.75            5.25
St. Louis.......................................            2.87           35.88           19.01           19.61
St. Louis City..................................            2.88           11.19            4.23            2.92
                                                 ---------------------------------------------------------------
    Total.......................................           13.86           69.81           38.21           33.42
----------------------------------------------------------------------------------------------------------------

                      Table 6--Change in NOX and VOC Emissions in the Missouri Portion of the St. Louis Area Between 2011 and 2014
                                                                          [tpd]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                NOX                                             VOC
                                                         -----------------------------------------------------------------------------------------------
                                                               2011            2014         Net change         2011            2014         Net change
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...................................................           90.68           81.70           -8.98           14.58           13.86           -0.72
Area....................................................            5.60            6.47            0.87           72.77           69.81           -2.96
Onroad..................................................          124.21          111.76          -12.45           38.00           38.21            0.21
Nonroad.................................................           47.55           38.44           -9.11           39.03           33.42           -5.61
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................          268.04          238.37          -29.67          164.38          155.30           -9.08
--------------------------------------------------------------------------------------------------------------------------------------------------------

    As indicated in table 6, total NOX and VOC emissions 
decreased by nearly 30 and 9 tpd respectively from the base year to the 
attainment year.\13\ Based on the control measures identified above in 
conjuction with the emission reductions, Missouri has adequately 
deomonstrated that the improvement in air quality is due to permanent 
and enforceable emission reductions.
---------------------------------------------------------------------------

    \13\ In a letter submitted by MDNR and received by EPA August 7, 
2017, the state provided clarifying information on NOx and VOC 
emissions. This letter and the original submission can be found in 
the docket for this action.
---------------------------------------------------------------------------

D. Criteria (4)--The Area Has a Fully Approvable Ozone Maintenance Plan 
Pursant to Section 175 of the CAA

    As one of the criteria for redesignation to attainment, section 
107(d)(3)(E)(iv) of the CAA requires EPA to determine that the area has 
a fully approved maintenance plan pursuant to section 175A of the CAA. 
Section 175A of the CAA sets forth the elements of a maintenance plan 
for areas seeking redesignation from nonattainment to attainment. Under 
section 175A, the maintenance plan must demonstrate continued 
attainment of the NAAQS for at least ten years after the Administrator 
approves a redesignation to attainment. Eight years after the 
redesignation, the state must submit a revised maintenance plan which 
demonstrates that attainment of the NAAQS will continue for an 
additional ten years beyond the initial ten year maintenance period. To 
address the possibility of future NAAQS violations, the maintenance 
plan must contain contingency measures, as EPA deems necessary, to 
assure prompt correction of the future NAAQS violation.
    In conjunction with its request to redesignate the Missouri portion 
of the St. Louis area to attainment for the 2008 ozone standard, MDNR 
submitted a SIP revision to provide for maintenance of the 2008 ozone 
standard through 2030, more than ten years after the expected effective 
date of the redesignation to attainment. As discussed below, EPA is 
proposing that this maintenance plan meets the requirements for 
approval under section 175A of the CAA.
    The Calcagni Memorandum provides further guidance on the content of 
a maintenance plan, explaining that a maintenance plan should address 
five elements: (1) An attainment emission inventory; (2) a maintenance 
demonstration; (3) a commitment for continued air quality monitoring; 
(4) a process for verification of continued attainment; and (5) a 
contingency plan. EPA is proposing to find that Missouri's ozone 
maintenance plan includes these necessary components and, as part of 
this action, is proposing to approve the maintenance plan as a revision 
of the Missouri SIP.
1. Attainment Emissions Inventory
    EPA is proposing to determine that the St. Louis area has attained 
the 2008 ozone NAAQS based on monitoring data for the period of 2013-
2015. As previously stated, MDNR selected 2014 as the attainment 
emissions inventory

[[Page 29495]]

year to establish attainment emission levels for NOX and 
VOC. The attainment emissions inventory identifies the levels of 
emissions in the Missouri portion of the St. Louis area that are 
sufficient to attain the 2008 ozone NAAQS. The derivation of the 
attainment year emissions is discussed above in section IV of this 
proposed rule. The attainment level emissions, by source category, are 
summarized in tables 4 and 5.
2. Maintenance Demonstration
    Missouri has demonstrated maintenance of the 2008 ozone standard 
through 2030 by assuring that current and future emissions of VOC and 
NOX for the St. Louis area remain at or below attainment 
year emission levels. A maintenance demonstration does not need to be 
based on modeling.\14\
---------------------------------------------------------------------------

    \14\ See Wall v. EPA, 265 F.3d 426 (6th Cir. 2001), Sierra Club 
v. EPA, 375 F. 3d 537 (7th Cir. 2004). See also 66 FR 53094, 66 FR 
53099-66 FR 53100 (October 19, 2001), 68 FR 25413, 68 FR 25430-68 FR 
25432 (May 12, 2003).
---------------------------------------------------------------------------

    Missouri used emissions for the 2014 year as a baseline and 
compared them to projected emissions for 2020 and 2030 to demonstrate 
maintenance. The year 2030 is more than ten years after the expected 
effective date of the redesignation to attainment and the year 2020 was 
selected to demonstrate that emissions are not expected to spike in the 
interim between the attainment year and the final maintenance year. The 
emissions inventories were developed as described below.
    For point, area, and nonroad emissions inventory development, 
Missouri estimated 2030 emissions by using the 2014 base year inventory 
and applying growth factors appropriate for each source category. For 
area sources, Stage II refueling emissions were calculated using MOVES 
and assumed that Stage II vehicle refueling vapor recovery controls 
would no longer be required by 2030.\15\
---------------------------------------------------------------------------

    \15\ Missouri developed and submitted a SIP revision to remove 
Stage II vapor recovery requirements in the Missouri portion of the 
St. Louis-St. Charles-Farmington, MO-IL area. EPA approved the 
revision and the action became effective on December 10, 2015. See 
80 FR 69602.
---------------------------------------------------------------------------

    For non-EGU and nonpoint emissions inventory development, Missouri 
collected data from the 2011NEIv2-based platform (2011v6.2) inventories 
for years 2011, 2017, and 2025. Missouri then calculated growth factors 
for years 2017 and 2025 by dividing 2011 annual emissions by 2017 and 
2025 annual emissions. Then, to estimate 2020 and 2030 growth factors, 
the program interpolated the 2017 and 2025 growth factors and then 
extrapolated to 2030. Missouri then used the TREND function in Excel to 
obtain data for 2026-2030. Summer day inventories were derived for 
these sectors using the methodology described above.
    For EGU emissions, Missouri decided to use 2011v6.2 emissions from 
2017 for 2020 and emissions from 2025 for 2030 because MDNR believes 
that it was not appropriate to use the same growth methodology for non-
EGUs and EGUs, as growth in the EGU sector depends on energy demand and 
environmental, transmission, dispatch, and reliability constraints.
    Finally, onroad mobile source emissions were developed using EPA's 
MOVES program with Vehicle Miles Traveled (VMT) data gathered from the 
East-West Gateway Council of Governments (EWGW) in coordination with 
the St. Louis Transportation Conformity Interagency Consultation Group. 
Missouri specifically used MOVES version 2014a-20151201 as it was the 
latest release at the time of inventory development. In developing the 
future year inventories, Missouri developed several future year model 
input tables, specifically age distribution, VMT, and vehicle 
population tables for 2020 and 2030. These input tables were developed 
with the help of MODOT, the Federal Highway Administration, and the 
EWGW. The emissions data for 2020 and 2030 is shown below in tables 7 
through 11.

         Table 7--Missouri Portion of the St. Louis Area NOX Emissions for Interim Maintenance Year 2020
                                                      [tpd]
----------------------------------------------------------------------------------------------------------------
                     County                            Point           Area           Onroad          Nonroad
----------------------------------------------------------------------------------------------------------------
Franklin........................................           30.92            3.11            5.99            4.03
Jefferson.......................................           23.58            1.18            4.99            2.19
St. Charles.....................................            8.82            2.41            7.89            5.28
St. Louis.......................................           21.19            6.37           23.60           12.65
St. Louis City..................................            4.09            3.79            3.95            4.13
                                                 ---------------------------------------------------------------
    Total.......................................            88.6           16.87           46.42           28.27
----------------------------------------------------------------------------------------------------------------

         Table 8--Missouri Portion of the St. Louis Area VOC Emissions for Interim Maintenance Year 2020
                                                      [tpd]
----------------------------------------------------------------------------------------------------------------
                     County                            Point           Area           Onroad          Nonroad
----------------------------------------------------------------------------------------------------------------
Franklin........................................            2.50            5.87            7.89            2.06
Jefferson.......................................            1.75            5.38            2.41            2.17
St. Charles.....................................            4.17           11.39            3.90            4.21
St. Louis.......................................            3.06           35.03           10.47           17.84
St. Louis City..................................            2.84           11.16            1.97            2.44
                                                 ---------------------------------------------------------------
    Total.......................................           14.32           68.86           26.64           28.71
----------------------------------------------------------------------------------------------------------------

         Table 9--Missouri Portion of the St. Louis Area NOX Emissions for Interim Maintenance Year 2030
                                                      [tpd]
----------------------------------------------------------------------------------------------------------------
                     County                            Point           Area           Onroad          Nonroad
----------------------------------------------------------------------------------------------------------------
Franklin........................................           30.92            2.20            3.22            1.97

[[Page 29496]]

 
Jefferson.......................................           27.72            0.88            2.73            2.32
St. Charles.....................................            8.87            1.81            4.34            5.88
St. Louis.......................................           21.75            5.44           13.10           16.93
St. Louis City..................................            3.82            2.70            2.18            2.80
                                                 ---------------------------------------------------------------
    Total.......................................           93.08           13.03           25.57           29.90
----------------------------------------------------------------------------------------------------------------

        Table 10--Missouri Portion of the St. Louis Area VOC Emissions for Interim Maintenance Year 2030
                                                      [tpd]
----------------------------------------------------------------------------------------------------------------
                     County                            Point           Area           Onroad          Nonroad
----------------------------------------------------------------------------------------------------------------
Franklin........................................            2.32            5.82            5.45            1.79
Jefferson.......................................            1.96            5.38            1.70            2.13
St. Charles.....................................            4.17           11.38            2.72            4.04
St. Louis.......................................            3.08           35.11            7.21           19.45
St. Louis City..................................            2.78           11.12            1.34            2.60
                                                 ---------------------------------------------------------------
    Total.......................................           14.31           68.80           18.42           30.01
----------------------------------------------------------------------------------------------------------------

                      Table 11--Change in NOX and VOC Emissions in the Missouri Portion of the St. Louis Area Between 2014 and 2030
                                                                          [tpd]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          NOX                                                 VOC
                                                 -------------------------------------------------------------------------------------------------------
                                                                                          Net change                                          Net change
                                                      2014         2020         2030     (2014-2030)      2014         2020         2030     (2014-2030)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...........................................        81.70         88.6        93.08        11.38        13.86        14.32        14.31         0.45
Area............................................         6.47        16.87        13.03         6.58        69.81        68.86        68.80        -1.01
Onroad..........................................       111.76        46.42        25.57       -86.19        38.21        26.64        18.42       -19.79
Nonroad.........................................        38.44        28.27        29.90        -8.54        33.42        28.71        30.01        -3.41
                                                 -------------------------------------------------------------------------------------------------------
    Total.......................................       238.37       180.16       161.58       -76.79       155.30       138.53       131.54       -23.76
--------------------------------------------------------------------------------------------------------------------------------------------------------

    In summary, the maintenance demonstration for the Missouri portion 
of the St. Louis area demonstrates maintenance of the 2008 ozone 
standard. It does so by providing emissions information that future 
emissions of NOX and VOC will remain at or below 2014 
emission levels when taking into account both future source growth and 
implementation of future controls.
    Table 11 shows NOX and VOC emissions in the Missouri 
portion of the St. Louis area are projected to decrease by 76.79 tpd 
and 23.76 tpd, respectively, between 2014 and 2030.
    In addition, since the St. Louis area covers both Missouri and 
Illinois, MDNR provided data from the Illinois portion of the St. Louis 
area. This data is summarized below in table 12 and shows that the 
Illinois portion of the St. Louis area will also show decreases in 
NOX and VOC emissions from 2014 to 2030. This data is 
provided here for informational purposes only as the EPA is not 
proposing to redesignate the Illinois portion of the St. Louis area in 
this action.

       Table 12--Change in NOX and VOC Emissions in the Illinois Portion of the St. Louis-St. Charles-Farmington, MO-IL Area Between 2014 and 2030
                                                                          [tpd]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        NOX                                                  VOC
                                               ---------------------------------------------------------------------------------------------------------
                                                                                        Net change                                           Net change
                                                    2014         2020         2030      (2014-2030)      2014         2020         2030      (2014-2030)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point.........................................        23.29        16.81        16.93         -6.36         9.38         9.03         8.53         -0.84
Area..........................................         1.53         1.51         1.51         -0.02        19.06        18.39        18.05         -1.00
Onroad........................................        26.94        13.22         6.71        -20.24        10.11         6.38         3.76         -6.36
Nonroad.......................................        24.62        18.44        11.31        -13.31         7.47         5.65         5.09         -2.38
                                               ---------------------------------------------------------------------------------------------------------
    Total.....................................        76.38        49.98        36.46        -39.93        46.02        39.45        35.43        -10.58
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 29497]]

3. Continued Air Quality Monitoring
    MDNR has committed to continue to operate the ozone monitors listed 
in table 1 above and has committed to consult with the EPA prior to 
making changes to the existing monitoring network should changes become 
necessary in the future. Missouri remains obligated to meet monitoring 
requirements and continue to quality assure monitoring data in 
accordance with 40 CFR part 58, and to enter all data into the Air 
Quality System (AQS) in accordance with Federal guidelines. EPA 
approved Missouri's monitoring plan on December 19, 2017. See https://www.epa.gov/mo/region-7-states-air-quality-monitoring-plans-missouri.
4. Verification of Continued Attainment
    The State of Missouri has the legal authority to enforce and 
implement the requirements of the maintenance plan for the Missouri 
portion of the St. Louis area. This includes the authority to adopt, 
implement, and enforce any subsequent emission control measures 
determined to be necessary to correct future ozone attainment problems.
    Verification of continued attainment is accomplished through 
operation of the ambient ozone monitoring network and the periodic 
update of the area's emissions inventory. MDNR will continue to operate 
the current ozone monitors located in the Missouri portion of the St. 
Louis area. There are no plans to discontinue operation, relocate, or 
otherwise change the existing ozone monitoring network other than 
through revisions in the network approved by the EPA.\16\
---------------------------------------------------------------------------

    \16\ EPA approved the 2016 Missouri Monitoring Network Plan on 
December 29, 2016.
---------------------------------------------------------------------------

    In addition, to track future levels of emissions, MDNR will 
continue to develop and submit to the EPA updated emission inventories 
for all source categories at least once every three years, consistent 
with the requirements of 40 CFR part 51, subpart A, and in 40 CFR 
51.122. The Consolidated Emissions Reporting Rule (CERR) was 
promulgated by EPA on June 10, 2002 (67 FR 39602). The CERR was 
replaced by the Annual Emissions Reporting Requirements (AERR) on 
December 17, 2008 (73 FR 76539). The most recent triennial inventory 
for Missouri was compiled for 2014. Point source facilities are covered 
by Missouri's emission statement rule, 10 CSR 10-6.110 (Reporting 
Emission Data, Emission Fees, and Process Information), and they will 
continue to submit VOC and NOX emissions on an annual basis.
5. Contingency Measures in the Maintenance Plan
    Section 175A of the CAA requires that the state must adopt a 
maintenance plan, as a SIP revision, that includes such contingency 
measures as the EPA deems necessary to assure that the state will 
promptly correct a violation of the NAAQS that occurs after 
redesignation of the area to attainment of the NAAQS. The maintenance 
plan must identify the following items: The contingency measures to be 
considered and, if needed for maintenance, adopted and implemented; a 
schedule and procedure for adoption and implementation; and, a time 
limit for action by the state. The state should also identify specific 
indicators to be used to determine when the contingency measures need 
to be considered, adopted, and implemented. The maintenance plan must 
include a commitment that the state will implement all measures with 
respect to the control of the pollutant that were contained in the SIP 
before redesignation of the area to attainment in accordance with 
section 175A(d) of the CAA.
    As required by section 175A of the CAA, Missouri has adopted a 
contingency plan for the Missouri portion of the St. Louis area to 
address possible future ozone air quality problems. The contingency 
plan adopted by Missouri has two levels of response, a warning level 
response and an action level response.
    In Missouri's plan, a Level I warning would occur if the fourth 
highest 8-hour ozone concentration at any monitoring site in the 
maintenance area (including sites in Missouri and Illinois) exceeds 
0.079 ppm in any year. A warning level response will consist of 
Missouri conducting a study to determine whether the ozone value 
indicates a trend toward higher ozone values or whether emissions 
appear to be increasing. The study will evaluate whether the trend, if 
any, is likely to continue and, if so, the control measures necessary 
to reverse the trend. The evaluation will be completed as expeditiously 
as possible, but no later than twenty-four months after MDNR has 
determined that a Level I trigger has occurred.
    In Missouri's plan, an action Level II response is triggered when a 
violation (based on the average of the last three (3) years' 4th 
highest maximum daily 8-hour average concentrations (40 CFR 50.15)) of 
the NAAQS at any monitoring station in the maintenance area occurs. 
When an action level response is triggered, MDNR will conduct an 
analysis to determine the appropriate measures to address the cause of 
the violation. This analysis will be completed within six months of the 
violation. Selected measures will be implemented as expeditiously as 
practicable, taking into consideration the ease of implementation and 
the technical and economic feasibility of the selected measure. The 
state committed to the implementation of contingency measures, under 
Level I or Level II triggers, taking place as expeditiously as 
practicable, but in no event later than twenty-four months after the 
state makes a determination that a trigger has occurred, based on 
quality-assured ambient data that has been entered into AQS. Missouri 
included the following list of potential contingency measures in its 
maintenance plan:
     Identify local sources with significant NOX 
and/or VOC emissions and develop controls through rules, NSR/PSD 
permits, or consent agreements;
     Work with MODOT and EWGW to implement transportation 
control measures (TCMs) through the Transportation Planning Process;
     Lower the applicability thresholds in existing rules that 
control NOX and VOCs;
     Lower emission limits in existing rules, specifically 
revisit current RACT rules;
     Develop new, or strengthen Alternative Control Techniques 
(ACTs) and Control Technique Guidelines (CTGs) for NOX and 
VOC sources;
     Develop rules to address contributing parts of Missouri 
outside of the St. Louis-St. Charles-Farmington, MO-IL area;
     Enhance the Heavy-Duty Diesel Anti-Idling Program;
     Update 10 CSR 10-6.130 (Controlling Emissions During 
Episodes of High Air Pollution Potential), specifically: Lowering the 
alert/action trigger levels, amending the rule to require alert/action 
level abatement plans at more facilities, and requiring existing 
abatement plans to be amended with more current emission reduction 
measures;
     Review other states' or multi-state organizations' rules 
and determine their applicability and effectiveness (i.e., reviewing 
the Ozone Transport Commission (OTC) model rules).
    EPA has concluded that the maintenance plan adequately addresses 
the five basic components of a maintenance plan: An attainment emission 
inventory, a maintenance demonstration, continued air quality 
monitoring, verification of continued attainment, and a contingency 
plan. In addition, as required by section 175A(b)

[[Page 29498]]

of the CAA, the state has committed to submit to the EPA an updated 
ozone maintenance plan eight years after redesignation of the Missouri 
portion of the St. Louis-St. Charles-Farmington, MO-IL area to cover an 
additional ten years beyond the initial ten-year maintenance period. 
Thus, the maintenance plan SIP revision submitted by MDNR for the 
Missouri portion of the St. Louis area meets the requirements of 
section 175A of the CAA, EPA proposes to approve it as a revision to 
the Missouri SIP.

V. Has the state adopted approvable Motor Vehicle Emission Budgets?

A. Motor Vehicle Emission Budgets

    Under section 176(c) of the CAA, new transportation plans, 
programs, or projects that receive Federal funding or support, such as 
the construction of new highways, must ``conform'' to (i.e., be 
consistent with) the SIP. Conformity to the SIP means that 
transportation activities will not cause new air quality violations, 
worsen existing air quality problems, or delay timely attainment of the 
NAAQS or interim air quality milestones. Regulations at 40 CFR part 93 
set forth the EPA policy, criteria, and procedures for demonstrating 
and assuring conformity of transportation activities to a SIP. 
Transportation conformity is a requirement for nonattainment and 
maintenance areas. Maintenance areas are areas that were previously 
nonattainment for a particular NAAQS, but that have been redesignated 
to attainment with an approved maintenance plan for the NAAQS.
    Under the CAA, states are required to submit, at various times, 
control strategy SIPs for nonattainment areas and maintenance plans for 
areas seeking redesignations to attainment of the ozone standard and 
maintenance areas.\17\ These control strategy SIPs (including 
reasonable further progress plans and attainment plans) and maintenance 
plans must include MVEBs for criteria pollutants, including ozone, and 
their precursor pollutants (VOC and NOX for ozone) to 
address pollution from onroad transportation sources. The MVEBs are the 
portion of the total allowable emissions that are allocated to highway 
and transit vehicle use that, together with emissions from other 
sources in the area, will provide for attainment or maintenance.\18\
---------------------------------------------------------------------------

    \17\ See the SIP requirements for the 2008 ozone standard in the 
EPA's March 6, 2015 implementation rule (80 FR 12264).
    \18\ See 40 CFR 93.101.
---------------------------------------------------------------------------

    Under 40 CFR part 93, a MVEB for an area seeking a redesignation to 
attainment must be established, at minimum, for the last year of the 
maintenance plan; a state may adopt MVEBs for other years as well. The 
MVEB serves as a ceiling on emissions from an area's planned 
transportation system and is further explained in the preamble to the 
November 24, 1993, Transportation Conformity Rule (58 FR 62188). The 
preamble also describes how to establish the MVEB in the SIP and how to 
revise the MVEB, if needed, subsequent to initially establishing a MVEB 
in the SIP.

B. What is the status of the EPA's adequacy determination for the 
proposed VOC and NOX MVEBs for the St. Louis area?

    When reviewing submitted control strategy SIPs or maintenance plans 
containing MVEBs, the EPA must affirmatively find that the MVEBs 
contained therein are adequate for use in determining transportation 
conformity. Once EPA affirmatively finds that the submitted MVEBs are 
adequate for transportation purposes, the MVEBs 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 at 40 CFR 93.118(e)(4). The process for determining adequacy 
consists of three basic steps: Public notification of a SIP submission; 
provision for 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 the ``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 (69 FR 40004).
    As discussed earlier, Missouri's maintenance plan includes 
NOX and VOC MVEBs for the Missouri portion of the St. Louis 
area for 2014 and 2030, the attainment level year and the last year of 
the maintenance period. EPA reviewed the VOC and NOX MVEBs 
with the adequacy process. Missouri's September 12, 2016 and February 
16, 2018, maintenance plan SIP submissions, including the VOC and 
NOX MVEBs for the area, were open for public comment on 
EPA's adequacy website on April 10, 2018, at: https://www.epa.gov/state-and-local-transportation/adequacy-review-state-implementation-plan-sip-submissions-conformity.
    The EPA public comment period on adequacy of the 2030 MVEBs for the 
Missouri portion of the St. Louis area closed on May 10, 2018. No 
comments on the submittal were received during the adequacy comment 
period. The submitted maintenance plan, which included the MVEBs, was 
endorsed by the Governor's designee, was subject to a state public 
hearing, and was developed as part of an interagency consultation 
process which includes Federal, state, and local agencies. These MVEBs, 
when considered together with all other emissions sources, are 
consistent with maintenance of the 2008 8-hour ozone standard.

                         Table 13--MVEBs for the Missouri Portion of the St. Louis Area
                                                      [tpd]
----------------------------------------------------------------------------------------------------------------
                                       Attainment year                         2030 mobile
                                         2014 onroad       2030 estimated     safety margin        2030 MVEBs
                                          emissions       onroad emissions      allocation
----------------------------------------------------------------------------------------------------------------
VOC.................................              38.21              18.42               3.58                 22
NOX.................................             111.76              25.57              14.43                 40
----------------------------------------------------------------------------------------------------------------

[[Page 29499]]

    As shown in table 13, the 2030 MVEBs exceed the estimated 2030 
onroad sector emissions. In an effort to accommodate future variations 
in travel demand models and vehicle miles traveled forecast, MDNR 
allocated a portion of the safety margin (described further below) to 
the mobile sector. Missouri has demonstrated that the Missouri portion 
of the St. Louis area can maintain the 2008 ozone NAAQS with mobile 
source emissions in the area of 22 tpd of VOC and 40 tpd of 
NOX in 2030, since despite partial allocation of the safety 
margin, emissions will remain under attainment year emission levels. 
Based on this analysis, the St. Louis area should maintain attainment 
of the 2008 ozone NAAQS for the relevant maintenance period with mobile 
source emissions at the levels of the MVEBs.
    Therefore, EPA has found that the MVEBs are adequate and is 
proposing to approve the MVEBs for use in determining transportation 
conformity in the Missouri portion of the St. Louis-St. Charles-
Farmington, MO-IL area.

C. What is a safety margin?

    A ``safety margin'' is the difference between the attainment level 
of emissions (from all sources) and the projected level of emissions 
(from all sources) in the maintenance plan. As noted in table 11, the 
emissions in the Missouri portion of the St. Louis-St. Charles-
Farmington, MO-IL area are projected to have safety margins of 76.79 
tpd for NOX and 23.76 tpd for VOC in 2030 (the difference 
between the attainment year 2014 emissions, and the projected 2030 
emissions for all sources in the Missouri portion of the St. Louis-St. 
Charles-Farmington, MO-IL area). Even if emissions reached the full 
level of the safety margin, the counties would still demonstrate 
maintenance since emission levels would equal less than those in the 
attainment year.
    As shown in table 13 above, Missouri is allocating a portion of 
that safety margin to the mobile source sector. Specifically, in 2030, 
Missouri is allocating 3.58 tpd and 14.43 tpd of the VOC and the 
NOX safety margins, respectively. MDNR is not requesting 
allocation to the MVEBs of the entire available safety margins 
reflected in the demonstration of maintenance. Therefore, even though 
the state is requesting MVEBs that exceed the projected onroad mobile 
source emissions for 2030 contained in the maintenance demonstration, 
the increase in onroad mobile source emissions that can be considered 
for transportation conformity purposes is well within the safety 
margins of the ozone maintenance demonstration. Further, once allocated 
to mobile sources, these safety margins will not be available for use 
by other sources.

VI. Proposed Action

    EPA is proposing to determine that the Missouri portion of the St. 
Louis nonattainment area is attaining the 2008 ozone standard based on 
quality-assured and certified monitoring data for 2013-2015 and that 
the Missouri portion of the St. Louis area has met the requirements for 
redesignation under section 107(d)(3)(E) of the CAA.
    EPA is also proposing to approve the state's request to change the 
designation of the Missouri portion of the St. Louis area for the 2008 
ozone standard from nonattainment to attainment. EPA is also proposing 
to approve, as a revision to the Missouri SIP, the state's maintenance 
plan for the area. The maintenance plan is designed to keep the 
Missouri portion of the St. Louis area in attainment of the 2008 ozone 
NAAQS through 2030. Finally, EPA finds adequate and is proposing to 
approve the newly-establisheed 2030 MVEBs for the Missouri portion of 
the St. Louis area.

VII. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submission that complies with the provisions of the Act and applicable 
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in 
reviewing SIP submissions, EPA's role is to approve state choices, 
provided that they meet the criteria of the CAA. Accordingly, this 
action merely approves state law as meeting Federal requirements and 
does not impose additional requirements beyond those imposed by state 
law. For that reason, this action:
     Is not a significant regulatory action subject to review 
by the Office of Management and Budget under Executive Orders 12866 (58 
FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011);
     Is not an Executive Order 13771 (82 FR 9339, February 2, 
2017) regulatory action because SIP approvals are exempted under 
Executive Order 12866.
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of the National Technology 
Transfer and Advancement Act (NTTA) because this rulemaking does not 
involve technical standards; and
     Does not provide EPA with the discretionary authority to 
address, as appropriate, disproportionate human health or environmental 
effects, using practicable and legally permissible methods, under 
Executive Order 12898 (59 FR 7629, February 16, 1994).
    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 rule does 
not have tribal implications and will not impose substantial direct 
costs on tribal governments or preempt tribal law as specified by 
Executive Order 13175 (65 FR 67249, November 9, 2000).

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Intergovernmental relations, Nitrogen dioxide, Ozone, 
Volatile organic compounds.

    Dated: June 13, 2018.
James B. Gulliford,
Regional Administrator, Region 7.
[FR Doc. 2018-13442 Filed 6-22-18; 8:45 am]
 BILLING CODE 6560-50-P