[Federal Register Volume 81, Number 188 (Wednesday, September 28, 2016)]
[Proposed Rules]
[Pages 66602-66617]
[FR Doc No: 2016-23301]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R05-OAR-2016-0269; FRL-9953-12-Region 5]

Air Plan Approval; Ohio; Redesignation of the Ohio Portion of the
Cincinnati-Hamilton, Ohio-Kentucky-Indiana Area to Attainment of the
2008 Ozone Standard

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to find
that the Cincinnati-Hamilton, Ohio-Kentucky-Indiana area is attaining
the 2008 8-hour ozone National Ambient Air Quality Standard (NAAQS or
standard) and to approve a request from the Ohio Environmental
Protection Agency (Ohio EPA) to redesignate the Ohio portion of the
Cincinnati-Hamilton area to attainment for the 2008 ozone NAAQS because
the request meets the statutory requirements for redesignation under
the Clean Air Act (CAA or Act). The Cincinnati-Hamilton area includes
Butler, Clermont, Clinton, Hamilton, and Warren Counties in Ohio;
Lawrenceburg Township in Dearborn County, Indiana; and, Boone,
Campbell, and Kenton Counties in Kentucky. Ohio EPA submitted this
request on April 21, 2016. EPA is also proposing to approve, as a
revision to the Ohio State Implementation Plan (SIP), the state's plan
for maintaining the 2008 8-hour ozone standard through 2030 in the
Cincinnati-Hamilton area. Finally, EPA finds adequate and is proposing
to approve the state's 2020 and 2030 volatile organic compound (VOC)
and oxides of nitrogen (NOX) Motor Vehicle Emission Budgets
(MVEBs) for the Ohio and Indiana portion of the Cincinnati-Hamilton
area.

DATES: Comments must be received on or before October 28, 2016.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R05-
OAR-2016-0269 at http://www.regulations.gov or via email to
<EMAIL_ADDRESS>For

comments submitted at Regulations.gov, follow the online instructions
for submitting comments. Once submitted, comments cannot be edited or
removed from Regulations.gov. For either manner of submission, EPA may
publish any comment received to its public docket. Do not submit
electronically any information you consider to be Confidential Business
Information (CBI) or other information whose disclosure is restricted
by statute. Multimedia submissions (audio, video, etc.) must be
accompanied by a written comment. The written comment is considered the
official comment and should include discussion of all points you wish
to make. EPA will generally not consider comments or comment contents
located outside of the primary submission (i.e. on the Web, cloud, or
other file sharing system). For additional submission methods, please
contact the person identified in the For Further Information Contact
section. For the full EPA public comment policy, information about CBI
or multimedia submissions, and general guidance on making effective
comments, please visit http://www2.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: Kathleen D'Agostino, Environmental
Scientist, Attainment Planning and Maintenance Section, Air Programs
Branch (AR-18J), Environmental Protection Agency, Region 5, 77 West
Jackson Boulevard, Chicago, Illinois 60604,<PHONE_NUMBER>,
<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION: Throughout this document whenever ``we,''
``us,'' or ``our'' is used, we mean EPA. This supplementary information
section is arranged as follows:

I. What are the actions EPA is proposing?
II. What is the background for these actions?
III. What are the criteria for redesignation?
IV. What is EPA's analysis of Ohio's redesignation request?
    A. Has the Cincinnati-Hamilton area attained the 2008 8-hour
ozone NAAQS?
    B. Has Ohio met all applicable requirements of section 110 and
part D of the CAA for the Cincinnati-Hamilton area, and does the
Ohio portion of the area have a fully approved SIP under section
110(k) of the CAA?
    1. Ohio Has Met All Applicable Requirements of Section 110 and
Part D of the CAA Applicable to the Ohio Portion of the Cincinnati-
Hamilton Area for Purposes of Redesignation
    2. The Ohio Portion of the Cincinnati-Hamilton Area Has a Fully
Approved SIP for Purposes of Redesignation Under Section 110(k) of
the CAA
    C. Are the air quality improvements in the Cincinnati-Hamilton
area due to permanent and enforceable emission reductions?
    1. Permanent and Enforceable Emission Controls Implemented
    2. Emission Reductions
    3. Meteorology
    D. Does Ohio have a fully approvable ozone maintenance plan for
the Cincinnati-Hamilton area?
    1. Attainment Inventory
    2. Has the state documented maintenance of the ozone standard in
the Cincinnati-Hamilton area?
    3. Continued Air Quality Monitoring
    4. Verification of Continued Attainment
    5. What is the contingency plan for the Cincinnati-Hamilton
area?
V. Has the state adopted approvable motor vehicle emission budgets?
    A. Motor Vehicle Emission Budgets
    B. What is the status of EPA's adequacy determination for the
proposed VOC and NOX MVEBs for the Cincinnati-Hamilton
area?
    C. What is a safety margin?
VI. Proposed Actions
VII. Statutory and Executive Order Reviews

I. What are the actions EPA is proposing?

    EPA is proposing to take several related actions. EPA is proposing
to determine that the Cincinnati-Hamilton nonattainment area is
attaining the 2008 ozone standard, based on quality-assured and
certified monitoring data for 2013-2015 and that the Ohio portion of
this area has met the requirements for redesignation under section
107(d)(3)(E) of the CAA. EPA is thus proposing to approve Ohio EPA's
request to change the legal designation of the Ohio portion of the
Cincinnati-Hamilton area from nonattainment to attainment for the 2008
ozone standard. EPA is also proposing to approve, as a revision to the
Ohio SIP, the state's maintenance plan (such approval being one of the
CAA criteria for redesignation to attainment status) for the area. The
maintenance plan is designed to keep the Cincinnati-Hamilton area in
attainment of the 2008 ozone NAAQS through 2030. Finally, EPA finds
adequate and is proposing to approve the newly-established 2020 and
2030 MVEBs for the Indiana and Ohio portion of the Cincinnati-Hamilton
area. The adequacy comment period for the MVEBs began on July 22, 2016,
with EPA's posting of the availability of the submittal on EPA's
Adequacy Web site (at http://www.epa.gov/otaq/stateresources/transconf/adequacy.htm). The adequacy comment period for these MVEBs ended on
August 22, 2016. EPA did not receive any requests for this submittal,
or adverse comments on this submittal during the adequacy comment
period. In a letter dated August 23, 2016, EPA informed Ohio EPA that
we found the 2020 and 2030 MVEBs to be 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 Ohio portion of the
Cincinnati-Hamilton area,'' for further explanation of this process.
Therefore, we find adequate, and are proposing to approve, the States'
2020 and 2030 MVEBs for transportation conformity purposes.

II. What is the background for these actions?

    EPA has determined that ground-level ozone is detrimental to human
health. On 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 in an area when the 3-year average of the annual fourth
highest daily maximum 8-hour average concentration is equal to or less
than 0.075 ppm, when truncated after the thousandth decimal place, at
all of the ozone monitoring sites in the area. See 40 CFR 50.15 and
appendix P to 40 CFR part 50.
    Upon promulgation of a new or revised NAAQS, section 107(d)(1)(B)
of the CAA requires EPA to designate as nonattainment any areas that
are violating the NAAQS, based on the most recent three years of
quality assured ozone monitoring data. The Cincinnati-Hamilton area was
designated as a marginal nonattainment area for the 2008 ozone NAAQS on
May 21, 2012 (77 FR 30088) (effective 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 section 181(a) of the CAA. This established an
attainment date three years after the July 20, 2012, effective
designation date for areas classified as marginal nonattainment for the
2008 ozone NAAQS. Therefore, the attainment date for the Cincinnati-
Hamilton area was July 20, 2015. On May 4, 2016 (81 FR 26697), in
accordance with section 181(b)(2)(A) of

the CAA and the provisions of the SIP Requirements Rule (40 CFR
51.1103), EPA made a determination that the Cincinnati-Hamilton area
attained the standard by its July 20, 2015, attainment date for the
2008 ozone NAAQS. EPA's determination was based upon 3 years of
complete, quality-assured and certified data for the 2012-2014 time
period.
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    \1\ This rule, titled ``Implementation of the 2008 National
Ambient Air Quality Standards for Ozone: State Implementation Plan
Requirements'' and published at 80 FR 12264 (March 6, 2015),
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 anti-backsliding
requirements that apply when the 1997 ozone NAAQS is revoked.
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III. What are the criteria for redesignation?

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

    1. ``Ozone and Carbon Monoxide Design Value Calculations,''
Memorandum from Bill Laxton. Director, Technical Support Division,
June 18, 1990;
    2. ``Maintenance Plans for Redesignation of Ozone and Carbon
Monoxide Nonattainment Areas,'' Memorandum from G.T. Helms, Chief,
Ozone/Carbon Monoxide Programs Branch, April 30, 1992;
    3. ``Contingency Measures for Ozone and Carbon Monoxide (CO)
Redesignations,'' Memorandum from G.T. Helms, Chief, Ozone/Carbon
Monoxide Programs Branch, June 1, 1992;
    4. ``Procedures for Processing Requests to Redesignate Areas to
Attainment,'' Memorandum from John Calcagni, Director, Air Quality
Management Division, September 4, 1992 (the ``Calcagni
Memorandum'');
    5. ``State Implementation Plan (SIP) Actions Submitted in
Response to Clean Air Act (CAA) Deadlines,'' Memorandum from John
Calcagni, Director, Air Quality Management Division, October 28,
1992;
    6. ``Technical Support Documents (TSDs) for Redesignation of
Ozone and Carbon Monoxide (CO) Nonattainment Areas,'' Memorandum
from G.T. Helms, Chief, Ozone/Carbon Monoxide Programs Branch,
August 17, 1993;
    7. ``State Implementation Plan (SIP) Requirements for Areas
Submitting Requests for Redesignation to Attainment of the Ozone and
Carbon Monoxide (CO) National Ambient Air Quality Standards (NAAQS)
On or After November 15, 1992,'' Memorandum from Michael H. Shapiro,
Acting Assistant Administrator for Air and Radiation, September 17,
1993;
    8. ``Use of Actual Emissions in Maintenance Demonstrations for
Ozone and CO Nonattainment Areas,'' Memorandum from D. Kent Berry,
Acting Director, Air Quality Management Division, November 30, 1993;
    9. ``Part D New Source Review (Part D NSR) Requirements for
Areas Requesting Redesignation to Attainment,'' Memorandum from Mary
D. Nichols, Assistant Administrator for Air and Radiation, October
14, 1994; and
    10. ``Reasonable Further Progress, Attainment Demonstration, and
Related Requirements for Ozone Nonattainment Areas Meeting the Ozone
National Ambient Air Quality Standard,'' Memorandum from John S.
Seitz, Director, Office of Air Quality Planning and Standards, May
10, 1995.

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

A. Has the Cincinnati-Hamilton area attained the 2008 8-hour ozone
NAAQS?

    For redesignation of a nonattainment area to attainment, the CAA
requires EPA to determine that the area has attained the applicable
NAAQS (CAA section 107(d)(3)(E)(i)). An area is attaining the 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
3-year period must also meet data completeness requirements. An ozone
design value is valid if daily maximum 8-hour average concentrations
are available for at least 90 percent of the days within the ozone
monitoring seasons,\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. For the 2012-2014 and 2013-2015 time periods, the ozone seasons
for Ohio, Indiana, and Kentucky were April-October, April-September,
and March-October, respectively. Beginning in 2016, the ozone
seasons for Ohio, Indiana and Kentucky are March-October. See, 80 FR
65292, 65466-67 (October 26, 2015).
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    On May 4, 2016, in accordance with section 181(b)(2)(A) of the CAA
and the provisions of the SIP Requirements Rule (40 CFR 51.1103), EPA
made a determination that the Cincinnati-Hamilton area attained the
standard by its July 20, 2015 attainment date for the 2008 ozone NAAQS.
This determination was based upon 3 years of complete, quality-assured
and certified data for the 2012-2014 time period. In addition, EPA has
reviewed the available ozone monitoring data from monitoring sites in
the Cincinnati-Hamilton area for the 2013-2015 time period. These data
have been quality assured, are recorded in the AQS, and have been
certified. These data demonstrate that the Cincinnati-Hamilton area is
attaining the 2008 ozone NAAQS. The annual fourth-highest 8-hour ozone
concentrations and the 3-year average of these concentrations
(monitoring site ozone design values) for each monitoring site are
summarized in Table 1.

 Table 1--Annual 4th High Daily Maximum 8-Hour Ozone Concentrations and 3-Year Average of the 4th High Daily Maximum 8-Hour Ozone Concentrations for the
                                                                Cincinnati-Hamilton Area
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                                                                                2013  4th high  2014  4th high  2015  4th high     2013-2015
                  State                              County                 Monitor            (ppm)           (ppm)           (ppm)       Average (ppm)
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Ohio                                      Butler.....................        39-017-0004           0.068           0.070           0.070           0.069
                                                                             39-017-0018           0.068           0.069           0.070           0.069

                                                                             39-017-9991           0.069           0.069           0.068           0.068
                                          Clermont...................        39-025-0022           0.066           0.068           0.070           0.068
                                          Clinton....................        39-027-1002           0.064           0.070           0.070           0.068
                                          Hamilton...................        39-061-0006           0.069           0.070           0.072           0.070
                                                                             39-061-0010           0.064           0.073           0.070           0.069
                                                                             39-061-0040           0.069           0.069           0.071           0.069
                                          Warren.....................        39-165-0007           0.067           0.071           0.071           0.069
Kentucky................................  Boone......................        21-015-0003           0.059           0.062           0.062           0.061
                                          Campbell...................        21-037-3002           0.072           0.071           0.071           0.071
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    The 3-year ozone design value for 2013-2015 is 0.071 ppm,\3\ which
meets the 2008 ozone NAAQS. Therefore, in today's action, EPA proposes
to determine that the Cincinnati-Hamilton area is attaining the 2008
ozone NAAQS.
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    \3\ The monitor ozone design value for the monitor with the
highest 3-year averaged concentration.
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    EPA will not take final action to determine that the Cincinnati-
Hamilton area is attaining the NAAQS nor to approve the redesignation
of this area if the design value of a monitoring site in the area
exceeds the NAAQS after proposal but prior to final approval of the
redesignation. Preliminary 2016 data indicate that this area continues
to attain the 2008 ozone NAAQS. As discussed in section IV.D.3. below,
Ohio EPA has committed to continue monitoring ozone in this area to
verify maintenance of the ozone standard.

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

    As criteria for redesignation of an area from nonattainment to
attainment of a NAAQS, the CAA requires EPA to determine that the state
has met all applicable requirements under section 110 and part D of
title I of the CAA (see section 107(d)(3)(E)(v) of the CAA) and that
the state has a fully approved SIP under section 110(k) of the CAA (see
section 107(d)(3)(E)(ii) of the CAA). EPA proposes to find that Ohio
has a fully approved SIP under section 110(k) of the CAA. Additionally,
EPA proposes to find that the Ohio SIP satisfies the criterion that it
meet applicable SIP requirements, for purposes of redesignation, under
section 110 and part D of title I of the CAA (requirements specific to
nonattainment areas for the 2008 ozone NAAQS). In making these proposed
determinations, EPA ascertained which CAA requirements are applicable
to the Cincinnati-Hamilton area and the Ohio SIP and, if applicable,
whether the required Ohio SIP elements are fully approved under section
110(k) and part D of the CAA. As discussed more fully below, SIPs must
be fully approved only with respect to currently applicable
requirements of the CAA.
    The September 4, 1992 Calcagni memorandum (see ``Procedures for
Processing Requests to Redesignate Areas to Attainment,'' Memorandum
from John Calcagni, Director, Air Quality Management Division,
September 4, 1992) describes EPA's interpretation of section
107(d)(3)(E) of the CAA. Under this interpretation, a state and the
area it wishes to redesignate must meet the relevant CAA requirements
that are due prior to the state's submittal of a complete redesignation
request for the area. See also the September 17, 1993, Michael Shapiro
memorandum and 60 FR 12459, 12465-66 (March 7, 1995) (redesignation of
Detroit-Ann Arbor, Michigan to attainment of the 1-hour ozone NAAQS).
Applicable requirements of the CAA that come due subsequent to the
state's submittal of a complete request remain applicable until a
redesignation to attainment is approved, but are not required as a
prerequisite to redesignation. See section 175A(c) of the CAA. Sierra
Club v. EPA, 375 F.3d 537 (7th Cir. 2004). See also 68 FR 25424, 25427
(May 12, 2003) (redesignation of the St. Louis/East St. Louis area to
attainment of the 1-hour ozone NAAQS).
1. Ohio Has Met All Applicable Requirements of Section 110 and Part D
of the CAA Applicable to the Ohio Portion of the Cincinnati-Hamilton
Area for Purposes of Redesignation
a. Section 110 General Requirements for Implementation Plans
    Section 110(a)(2) of the CAA delineates the general requirements
for a SIP. Section 110(a)(2) provides that the SIP must have been
adopted by the state after reasonable public notice and hearing, and
that, among other things, it must: (1) Include enforceable emission
limitations and other control measures, means or techniques necessary
to meet the requirements of the CAA; (2) provide for establishment and
operation of appropriate devices, methods, systems and procedures
necessary to monitor ambient air quality; (3) provide for
implementation of a source permit program to regulate the modification
and construction of stationary sources within the areas covered by the
plan; (4) include provisions for the implementation of part C
prevention of significant deterioration (PSD) and part D new source
review (NSR) permit programs; (5) include provisions for stationary
source emission control measures, monitoring, and reporting; (6)
include provisions for air quality modeling; and, (7) provide for
public and local agency participation in planning and emission control
rule development.
    Section 110(a)(2)(D) of the CAA requires SIPs to contain measures
to prevent sources in a state from significantly contributing to air
quality problems in another state. To implement this provision, EPA has
required certain states to establish programs to address transport of
certain air pollutants, e.g., NOX SIP call.\4\

However, like many of the 110(a)(2) requirements, the section
110(a)(2)(D) SIP requirements are not linked with a particular area's
ozone designation and classification. EPA concludes that the SIP
requirements linked with 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,
we believe these requirements are not applicable requirements for
purposes of redesignation. See 65 FR 37890 (June 15, 2000), 66 FR 50399
(October 19, 2001), 68 FR 25418, 25426-27 (May 13, 2003).
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    \4\ On October 27, 1992 (63 FR 57356), EPA issued a
NOX SIP call requiring the District of Columbia and 22
states to reduce emissions of NOX in order to reduce the
transport of ozone and ozone precursors. In compliance with EPA's
NOX SIP call, Ohio developed rules governing the control
of NOX emissions from Electric Generating Units (EGUs),
major non-EGU industrial boilers and turbines, and major cement
kilns. EPA approved Ohio's rules as fulfilling Phase I of the
NOX SIP Call on August 5, 2003 (68 FR 46089) and June 27,
2005 (70 FR 36845), and as meeting Phase II of the NOX
SIP Call on February 4, 2008 (73 FR 6427).
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    In addition, EPA believes that other section 110 elements that are
neither connected with nonattainment plan submissions nor linked with
an area's ozone attainment status are not applicable requirements for
purposes of redesignation. The area will still be subject to these
requirements after the area is redesignated to attainment of 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 in reviewing a redesignation request.
This approach is consistent with EPA's existing policy on applicability
(i.e., for redesignations) of conformity and oxygenated fuels
requirements, as well as with section 184 ozone transport requirements.
See Reading, Pennsylvania proposed and final rulemakings, 61 FR 53174-
53176 (October 10, 1996) and 62 FR 24826 (May 7, 1997); Cleveland-
Akron-Loraine, Ohio final rulemaking, 61 FR 20458 (May 7, 1996); and
Tampa, Florida final rulemaking, 60 FR 62748 (December 7, 1995). See
also the discussion of this issue in the Cincinnati, Ohio ozone
redesignation (65 FR 37890, June 19, 2000), and the Pittsburgh,
Pennsylvania ozone redesignation (66 FR 50399, October 19, 2001).
    We have reviewed Ohio's SIP and have concluded that it meets the
general SIP requirements under section 110 of the CAA, to the extent
those requirements are applicable for purposes of redesignation. On
October 16, 2014 (79 FR 62019), EPA approved elements of the SIP
submitted by Ohio 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 8-hour ozone
nonattainment status of the Cincinnati-Hamilton area. Therefore, EPA
concludes that these infrastructure requirements are not applicable
requirements for purposes of review of the state's 8-hour ozone
redesignation request.
b. Part D Requirements
    Section 172(c) of the CAA sets forth the basic requirements of air
quality plans for states with nonattainment areas that are required to
submit them pursuant to section 172(b). Subpart 2 of part D, which
includes section 182 of the CAA, establishes specific requirements for
ozone nonattainment areas depending on the areas' nonattainment
classifications.
    The Cincinnati-Hamilton 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).
i. Subpart 1 Section 172 Requirements
    As provided in subpart 2, for marginal ozone nonattainment areas
such as the Cincinnati-Hamilton area, the specific requirements of
section 182(a) apply in lieu of the attainment planning requirements
that would otherwise apply under section 172(c), including the
attainment demonstration and reasonably available control measures
(RACM) under section 172(c)(1), reasonable further progress (RFP) under
section 172(c)(2), and contingency measures under section 172(c)(9). 42
U.S.C. 7511a(a).
    Section 172(c)(3) requires submission and approval of a
comprehensive, accurate and current inventory of actual emissions. This
requirement is superseded by the inventory requirement in section
182(a)(1) discussed below.
    Section 172(c)(4) requires the identification and quantification of
allowable emissions for major new and modified stationary sources in an
area, and section 172(c)(5) requires source permits for the
construction and operation of new and modified major stationary sources
anywhere in the nonattainment area. EPA approved Ohio's NSR program on
January 10, 2003 (68 FR 1366) and February 25, 2010 (75 FR 8496).
Nonetheless, EPA has determined that, since PSD requirements will apply
after redesignation, areas being redesignated need not comply with the
requirement that a NSR program be approved prior to redesignation,
provided that the area demonstrates maintenance of the NAAQS without
part D NSR. A more detailed rationale for this view is described in a
memorandum from Mary Nichols, Assistant Administrator for Air and
Radiation, dated October 14, 1994, entitled, ``Part D New Source Review
Requirements for Areas Requesting Redesignation to Attainment.'' Ohio
has demonstrated that the Cincinnati-Hamilton area will be able to
maintain the standard without part D NSR in effect; therefore, EPA
concludes that the state need not have a fully approved part D NSR
program prior to approval of the redesignation request. See rulemakings
for Detroit, Michigan (60 FR 12467-12468, March 7, 1995); Cleveland-
Akron-Lorain, Ohio (61 FR 20458, 20469-20470, May 7, 1996); Louisville,
Kentucky (66 FR 53665, October 23, 2001); and Grand Rapids, Michigan
(61 FR 31834-31837, June 21, 1996). Ohio's PSD program will become
effective in the Cincinnati-Hamilton area upon redesignation to
attainment. EPA approved Ohio's PSD program on January 22, 2003 (68 FR
2909) and February 25, 2010 (75 FR 8496).
    Section 172(c)(6) requires the SIP to contain control measures
necessary to provide for attainment of the NAAQS. Because attainment
has been reached, no additional measures are needed to provide for
attainment.
    Section 172(c)(7) requires the SIP to meet the applicable
provisions of section 110(a)(2). As noted above, we believe the Ohio
SIP meets the requirements of section 110(a)(2) for purposes of
redesignation.
ii. Section 176 Conformity Requirements
    Section 176(c) of the CAA requires states to establish criteria and
procedures to ensure that Federally supported or funded projects
conform to the air quality planning goals in the applicable SIP. The
requirement to determine conformity applies to transportation plans,
programs and projects that are developed, funded or approved under
title 23 of the United States Code (U.S.C.) and the Federal Transit Act
(transportation conformity)

as well as to all other Federally supported or funded projects (general
conformity). State transportation conformity SIP revisions must be
consistent with Federal conformity regulations relating to
consultation, enforcement and enforceability that EPA promulgated
pursuant to its authority under the CAA.
    EPA interprets the conformity SIP requirements \5\ as not applying
for purposes of evaluating a redesignation request under section 107(d)
because state conformity rules are still required after redesignation
and Federal conformity rules apply where state conformity rules have
not been approved. See Wall v. EPA, 265 F.3d 426 (6th Cir. 2001)
(upholding this interpretation); see also 60 FR 62748 (December 7,
1995) (redesignation of Tampa, Florida). Nonetheless, Ohio has an
approved conformity SIP for the Cincinnati-Hamilton area. See 80 FR
11133 (March 2, 2015).
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    \5\ CAA section 176(c)(4)(E) requires states to submit revisions
to their SIPs to reflect certain Federal criteria and procedures for
determining transportation conformity. Transportation conformity
SIPs are different from SIPs requiring the development of Motor
Vehicle Emission Budgets (MVEBs), such as control strategy SIPs and
maintenance plans.
---------------------------------------------------------------------------

iii. Section 182(a) Requirements
    Section 182(a)(1) requires states to submit a comprehensive,
accurate, and current inventory of actual emissions from sources of VOC
and NOX emitted within the boundaries of the ozone
nonattainment area. Ohio EPA submitted a 2008 base year emissions
inventory for the Cincinnati-Hamilton area on July 18, 2014. EPA
approved this emissions inventory as a revision to the Ohio SIP on
March 10, 2016 (81 FR 12591).
    Under section 182(a)(2)(A), states with ozone nonattainment areas
that were designated prior to the enactment of the 1990 CAA amendments
were required to submit, within six months of classification, all rules
and corrections to existing VOC reasonably available control technology
(RACT) rules that were required under section 172(b)(3) prior to the
1990 CAA amendments. The Cincinnati-Hamilton 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 Ohio complied with
this requirement for the Cincinnati-Hamilton area under the prior 1-
hour ozone NAAQS. See 59 FR 23796 (May 9, 1994) and 60 FR 15235 (March
23, 1995).
    Section 182(a)(2)(B) requires each state with a marginal ozone
nonattainment area that implemented or was required to implement a
vehicle inspection and maintenance (I/M) program prior to the 1990 CAA
amendments to submit a SIP revision for an I/M program no less
stringent than that required prior to the 1990 CAA amendments or
already in the SIP at the time of the CAA amendments, whichever is more
stringent. For the purposes of the 2008 ozone standard and the
consideration of Ohio's redesignation request for this standard, the
Cincinnati-Hamilton area is not subject to the section 182(a)(2)(B)
requirement because the Cincinnati-Hamilton 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), Ohio currently has a fully-approved
part D NSR program in place. EPA approved Ohio's PSD program on January
22, 2003 (68 FR 2909) and February 25, 2010 (75 FR 8496). As discussed
above, Ohio has demonstrated that the Cincinnati-Hamilton area will be
able to maintain the standard without part D NSR in effect; therefore,
EPA concludes that the state need not have a fully approved part D NSR
program prior to approval of the redesignation request. The state's PSD
program will become effective in the Cincinnati-Hamilton area upon
redesignation to attainment.
    Section 182(a)(3) requires states to submit periodic emission
inventories and a revision to the SIP to require the owners or
operators of stationary sources to annually submit emission statements
documenting actual VOC and NOX emissions. As discussed below
in section IV.D.4. of this proposed rule, Ohio will continue to update
its emissions inventory at least once every three years. With regard to
stationary source emission statements, EPA approved Ohio's emission
statement rule on September 27, 2007 (72 FR 54844). On July 18, 2014,
Ohio certified that this approved SIP regulation remains in place and
remains enforceable for the 2008 ozone standard. EPA approved Ohio's
certification on March 10, 2016 (81 FR 12591).
    The Ohio portion of the Cincinnati-Hamilton area has satisfied all
applicable requirements for purposes of redesignation under section 110
and part D of title I of the CAA.
2. The Ohio Portion of the Cincinnati-Hamilton Area Has a Fully
Approved SIP for Purposes of Redesignation Under Section 110(k) of the
CAA
    Ohio has adopted and submitted and EPA has approved at various
times, provisions addressing the various SIP elements applicable for
the ozone NAAQS. As discussed above, EPA has fully approved the Ohio
SIP for the Cincinnati-Hamilton area under section 110(k) for 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,
989-990 (6th Cir. 1998); Wall v. EPA, 265 F.3d 426), plus any
additional measures it may approve in conjunction with a redesignation
action (see 68 FR 25426 (May 12, 2003) and citations therein).

C. Are the air quality improvements in the Cincinnati-Hamilton area 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 other permanent and enforceable
emission reductions. EPA has determined that Ohio has demonstrated that
that the observed ozone air quality improvement in the Cincinnati-
Hamilton 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
Cincinnati-Hamilton area and upwind areas have implemented in recent
years. In addition, Ohio EPA provided an analysis to demonstrate the
improvement in air quality was not due to unusually favorable
meteorology. Based on the information summarized below, Ohio has
adequately demonstrated that the improvement in air quality is due to
permanent and enforceable emissions reductions.

1. Permanent and Enforceable Emission Controls Implemented
a. Regional NOX Controls
    Clean Air Interstate Rule (CAIR)/Cross State Air Pollution Rule
(CSAPR). CAIR created regional cap-and-trade programs to reduce sulfur
dioxide (SO2) and NOX emissions in 27 eastern
states, including Ohio, that contributed to downwind nonattainment and
maintenance of the 1997 8-hour ozone NAAQS and the 1997 fine
particulate matter (PM2.5) NAAQS. See 70 FR 25162 (May 12,
2005). EPA approved Ohio's CAIR regulations into the Ohio SIP on
February 1, 2008 (73 FR 6034), and September 25, 2009 (74 FR 48857). In
2008, the United States Court of Appeals for the District of Columbia
Circuit (D.C. Circuit) initially vacated CAIR, North Carolina v. EPA,
531 F.3d 896 (D.C. Cir. 2008), but ultimately remanded the rule to EPA
without vacatur to preserve the environmental benefits provided by
CAIR, North Carolina v. EPA, 550 F.3d 1176, 1178 (D.C. Cir. 2008). On
August 8, 2011 (76 FR 48208), acting on the D.C. Circuit's remand, EPA
promulgated CSAPR to replace CAIR and thus to address the interstate
transport of emissions contributing to nonattainment and interfering
with maintenance of the two air quality standards covered by CAIR as
well as the 2006 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 \6\ was reversed by the
United States Supreme Court on April 29, 2014, and the case was
remanded to the D.C. Circuit to resolve remaining issues in accordance
with the high court's ruling. EPA v. EME Homer City Generation, L.P.,
134 S. Ct. 1584 (2014). On remand, the D.C. Circuit affirmed CSAPR in
most respects, but invalidated without vacating some of the CSAPR
budgets as to a number of states. EME Homer City Generation, L.P. v.
EPA, 795 F.3d 118 (D.C. Cir. 2015). The remanded budgets include the
Phase 2 NOX ozone season emissions budgets for Ohio. 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 were originally
promulgated to begin on January 1, 2014, and are now scheduled to begin
on January 1, 2017. CSAPR will continue to operate under the existing
emissions budgets until EPA addresses the D.C. Circuit's remand.
---------------------------------------------------------------------------

    \6\ EME Homer City Generation, L.P. v. EPA, 696 F.3d 7, 38 (D.C.
Cir. 2012).
---------------------------------------------------------------------------

    While the reduction in NOX emissions from the
implementation of CSAPR will result in lower concentrations of
transported ozone entering the Cincinnati-Hamilton area throughout the
maintenance period, EPA is proposing to approve the redesignation of
the Ohio portion of the Cincinnati-Hamilton area without relying on
those measures within Ohio as having led to attainment of the 2008
ozone NAAQS or contributing to maintenance of that standard. In so
doing, we are proposing to determine that the D.C. Circuit's
invalidation of the Ohio CSAPR Phase 2 ozone season NOX
emissions budget does not bar today's proposed redesignation.
    The improvement in ozone air quality in the Cincinnati-Hamilton
area from 2011 (a year when the design value for the area was above the
NAAQS) to 2014 (a year when the design value was below the NAAQS) is
not due to CSAPR emissions reductions because, as noted above, CSAPR
did not go into effect until January 1, 2015, after the area was
already attaining the standard. As a general matter, because CSAPR is
CAIR's replacement, emissions reductions associated with CAIR will for
most areas be made permanent and enforceable through implementation of
CSAPR. In addition, EPA has preliminarily determined that the vast
majority of reductions in emissions in the Ohio portion of the
Cincinnati-Hamilton area from 2011-2014 were due to permanent and
enforceable reductions in mobile source VOC and NOX
emissions.
    EPA found that from 2011 to 2014, onroad and nonroad mobile source
emission reductions accounted for 80 percent of the total
NOX reductions and 98 percent of the total VOC reductions in
the Ohio portion of the Cincinnati-Hamilton area. As laid out in the
State's maintenance demonstration, NOX and VOC emissions in
the Ohio portion of the area are projected to continue their downward
trend throughout the maintenance period, driven primarily by mobile
source measures. From 2014 to 2030, Ohio projected that 75 percent of
the NOX emission reductions and 96 percent of the VOC
reductions in the Ohio portion of the area would be due to mobile
source measures based on EPA-approved mobile source modeling. Even if
no NOX reductions are assumed from point sources within the
Ohio portion of the Cincinnati-Hamilton area, NOX emissions
in 2030 are projected to be 30 percent less than in attainment year
2014.
    Given the particular facts and circumstances associated with the
Cincinnati-Hamilton area, EPA does not believe that the D.C. Circuit's
invalidation of Ohio's CSAPR Phase 2 NOX ozone season
budget, which replaced CAIR's NOX ozone season budget, is a
bar to EPA's redesignation of the Ohio portion of the Cincinnati-
Hamilton area for the 2008 ozone NAAQS.
b. Federal 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 include the following.
    Tier 2 Emission Standards for Vehicles and Gasoline Sulfur
Standards. On February 10, 2000 (65 FR 6698), EPA promulgated Tier 2
motor vehicle emission standards and gasoline sulfur control
requirements. These emission control requirements result in lower VOC
and 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.
    Tier 3 Emission Standards for Vehicles and Gasoline Sulfur
Standards. On April 28, 2014 (79 FR 23414), EPA promulgated Tier 3
motor vehicle

emission and fuel standards to reduces both tailpipe and evaporative
emissions and to further reduce the sulfur content in fuels. The rule
will be phased in between 2017 and 2025. Tier 3 sets new tailpipe
standards for the sum of VOC and NOX and for particulate
matter. The VOC and NOX tailpipe standards for light-duty
vehicles represent approximately an 80% reduction from today's fleet
average and a 70% reduction in per-vehicle particulate matter (PM)
standards. Heavy-duty tailpipe standards represent about a 60%
reduction in both fleet average VOC and NOX and per-vehicle
PM standards. The evaporative emissions requirements in the rule will
result in approximately a 50 percent reduction from current standards
and apply to all light-duty and onroad gasoline-powered heavy-duty
vehicles. Finally, the rule lowers the sulfur content of gasoline to an
annual average of 10 ppm by January 2017. While these reductions did
not aid the area in attaining the standard, emission reductions will
occur during the maintenance period.
    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
rule. 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. As projected by these estimates and demonstrated in the
on-road emission modeling for the Cincinnati-Hamilton area, some of
these emission reductions occurred by the attainment years and
additional emission reductions will occur throughout the maintenance
period, as older vehicles are replaced with newer, compliant model
years.
    Nonroad Diesel Rule. On June 29, 2004 (69 FR 38958), EPA issued a
rule adopting emissions standards for nonroad diesel engines and sulfur
reductions in nonroad diesel fuel. This rule applies to diesel engines
used primarily in construction, agricultural, and industrial
applications. Emission standards are phased in for 2008 through 2015
model years based on engine size. The SO2 limits for nonroad
diesel fuels were phased in from 2007 through 2012. EPA estimates that
when fully implemented, compliance with this rule will cut
NOX emissions from these nonroad diesel engines by
approximately 90 percent. Some of these emission reductions occurred by
the attainment years and additional emission reductions will occur
throughout the maintenance period.
    Nonroad Spark-Ignition Engines and Recreational Engine Standards.
On November 8, 2002 (67 FR 68242), EPA adopted emission standards for
large spark-ignition engines such as those used in forklifts and
airport ground-service equipment; recreational vehicles such as off-
highway motorcycles, all-terrain vehicles, and snowmobiles; and
recreational marine diesel engines. These emission standards are phased
in from model year 2004 through 2012. When fully implemented, EPA
estimates an overall 72 percent reduction in VOC emissions from these
engines and an 80 percent reduction in 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
9648), 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 is fully implemented in 2013, NOX and
VOC emissions from these engines will 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 Cincinnati-Hamilton Area
    Changes at several EGUs have resulted in reductions in
NOX emissions. Tanner's Creek Generating Station in Dearborn
County, Indiana permanently shut down in May 2015. Prior to the
shutdown, NOX emissions had dropped from 15.08 tons per
summer day (TPSD) in 2011 to 10.6 TPSD in 2014. The Walter C. Beckjord
facility in Clermont County, Ohio permanently shut down in October of
2014. Prior to the shutdown, NOX emissions from EGUs in
Clermont County dropped from 43.41 TPSD in 2011 to 41.17 TPSD in 2014,
partly attributable to the Walter C. Beckjord facility. Finally, Unit 3
(163 megawatts) of the Miami Fort facility in Hamilton County, Ohio
permanently shut down in June of 2015. Prior to shutdown,
NOX emissions from EGUs in Hamilton County dropped from
17.72 TPSD in 2011 to 17.46 TPSD in 2014, partly attributable to
reductions at unit 3 at Miami Fort.
2. Emission Reductions
    Ohio is using a 2011 inventory as the nonattainment base year.
Area, nonroad mobile, airport related emissions (AIR), and point source
emissions (EGUs and non-EGUs) were collected from the Ozone NAAQS
Implementation Modeling platform (2011v6.1). For 2011, this represents
actual data reported to EPA by the states 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 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. Onroad
mobile source emissions were developed in conjunction with the Ohio-
Kentucky-Indiana Regional Council of Governments (OKI) and were
calculated from emission factors produced by EPA's 2014 Motor Vehicle
Emission Simulator (MOVES) model and data extracted from the region's
travel-demand model.
    For the attainment inventory, Ohio is using 2014, one of the years
the Cincinnati-Hamilton area monitored attainment of the 2008 ozone
standard. Because the 2014 NEI inventory was not available at the time
Ohio EPA was compiling the redesignation request, the state was unable
to use the 2014 NEI inventory directly. For area, nonroad mobile, and
AIR, 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 databases, 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 in conjunction
with OKI using the same methodology described above for the 2011
inventory.
    Using the inventories described above, Ohio's submittal documents
changes in VOC and NOX emissions from 2011 to 2014 for the
Cincinnati-Hamilton area. Emissions data are shown in Tables 2 through
7.

                                   Table 2--Cincinnati-Hamilton Area NOX Emissions for Nonattainment Year 2011 (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                         County                                Point            AIR           Nonroad          Area           Onroad           Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ohio:
    Butler..............................................           10.67            0.02            4.27            4.78           12.24           31.98
    Clermont............................................           43.55            0.00            2.27            1.14            7.52           54.48
    Clinton.............................................            0.00            0.00            1.15            0.52            4.53            6.20
    Hamilton............................................           26.29            0.02            8.56           10.09           33.69           78.65
    Warren..............................................            1.55            0.00            3.24            1.66            9.84           16.29
Indiana:
    Dearborn............................................           17.79            0.00            0.53            0.47            1.03           19.82
Kentucky:
    Boone...............................................            7.19            2.03            1.06            0.43            6.90           17.61
    Campbell............................................            0.17            0.00            0.38            0.49            4.30            5.34
    Kenton..............................................            0.01            0.00            0.77            1.02            6.53            8.33
                                                         -----------------------------------------------------------------------------------------------
        Ohio Totals.....................................           82.06            0.04           19.49           18.19           67.82          187.60
                                                         -----------------------------------------------------------------------------------------------
            Area Totals.................................          107.22            2.07           22.23           20.60           86.58          238.70
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                   Table 3--Cincinnati-Hamilton Area VOC Emissions for Nonattainment Year 2011 (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                         County                                Point            AIR           Nonroad          Area           Onroad           Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ohio:
    Butler..............................................            3.09            0.03            2.93            9.59           10.21           25.85
    Clermont............................................            0.49            0.01            1.95            5.41            6.27           14.13
    Clinton.............................................            0.00            0.01            0.84            2.49            2.27            5.61
    Hamilton............................................            2.62            0.04            7.44           21.88           28.09           60.07
    Warren..............................................            0.62            0.01            2.12            5.71            8.21           16.67
Indiana:
    Dearborn............................................            4.28            0.00            0.42            1.75            0.86            7.31
Kentucky:
    Boone...............................................            1.73            0.42            1.49            2.66            3.30            9.60
    Campbell............................................            0.22            0.00            0.40            1.29            2.05            3.96
    Kenton..............................................            0.51            0.00            0.62            2.51            3.12            6.76
                                                         -----------------------------------------------------------------------------------------------
        Ohio Totals.....................................            6.82            0.10           15.28           45.08           55.05          122.33
                                                         -----------------------------------------------------------------------------------------------
            Area Totals.................................           13.56            0.52           18.21           53.29           64.38          149.96
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                     Table 4--Cincinnati-Hamilton Area NOX Emissions for Attainment Year 2014 (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                         County                                Point            AIR           Nonroad          Area           Onroad           Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ohio:
    Butler..............................................           12.70            0.02            3.39            4.78            8.85           29.74
    Clermont............................................           41.20            0.00            1.81            1.14            5.44           49.59
    Clinton.............................................            0.00            0.00            0.96            0.52            3.51            4.99
    Hamilton............................................           21.65            0.02            6.76           10.08           24.37           62.88
    Warren..............................................            0.96            0.00            2.55            1.66            7.12           12.29
Indiana:
    Dearborn............................................           11.74            0.00            0.44            0.47            0.74           13.39
Kentucky:
    Boone...............................................            7.37            2.07            0.88            0.43            5.46           16.21
    Campbell............................................            0.17            0.00            0.32            0.49            3.41            4.39
    Kenton..............................................            0.01            0.00            0.64            1.02            5.17            6.84
                                                         -----------------------------------------------------------------------------------------------
        Ohio Totals.....................................           76.51            0.04           15.47           18.18           49.29          159.49
                                                         -----------------------------------------------------------------------------------------------
            Area Totals.................................           95.80            2.11           17.75           20.59           64.07          200.32
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                     Table 5--Cincinnati-Hamilton Area VOC Emissions for Attainment Year 2014 (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                         County                                Point            AIR           Nonroad          Area           Onroad           Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ohio:
    Butler..............................................            2.96            0.03            2.61            9.51            7.59           22.70
    Clermont............................................            0.63            0.01            1.73            5.36            4.66           12.39
    Clinton.............................................            0.01            0.01            0.71            2.51            1.53            4.77
    Hamilton............................................            2.73            0.04            6.54           21.66           20.88           51.85
    Warren..............................................            0.51            0.01            1.93            5.66            6.10           14.21
Indiana:
    Dearborn............................................            5.54            0.00            0.36            1.75            0.64            8.29
Kentucky:
    Boone...............................................            1.73            0.42            1.30            2.56            2.53            8.54
    Campbell............................................            0.22            0.00            0.34            1.26            1.58            3.40
    Kenton..............................................            0.51            0.00            0.55            2.43            2.39            5.88
                                                         -----------------------------------------------------------------------------------------------
        Ohio Totals.....................................            6.84            0.10           13.52           44.70           40.76          105.92
                                                         -----------------------------------------------------------------------------------------------
            Area Totals.................................           14.84            0.52           16.07           52.70           47.90          132.03
--------------------------------------------------------------------------------------------------------------------------------------------------------

               Table 6--Change in NOX and VOC Emissions Between 2011 and 2014 for the Ohio Portion of the Cincinnati-Hamilton Area (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                NOX                                             VOC
                                                         -----------------------------------------------------------------------------------------------
                                                                                Net change                                      Net change
                                                               2011            2014         (2011-2014)        2011            2014         (2011-2014)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...................................................           82.06           76.51           -5.55            6.82            6.84            0.02
AIR.....................................................            0.04            0.04            0.00            0.10            0.10            0.00
Nonroad.................................................           19.49           15.47           -4.02           15.28           13.52           -1.76
Area....................................................           18.19           18.18           -0.01           45.08           44.70           -0.38
Onroad..................................................           67.82           49.29          -18.53           55.05           40.76          -14.29
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................          187.60          159.49          -28.11          122.33          105.92          -16.41
--------------------------------------------------------------------------------------------------------------------------------------------------------

                      Table 7--Change in NOX and VOC Emissions Between 2011 and 2014 for the Entire Cincinnati-Hamilton Area (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                NOX                                             VOC
                                                         -----------------------------------------------------------------------------------------------
                                                                                Net change                                      Net change
                                                               2011            2014         (2011-2014)        2011            2014         (2011-2014)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...................................................          107.22           95.80          -11.42           13.56           14.84            1.28
AIR.....................................................            2.07            2.11            0.04            0.52            0.52            0.00
Nonroad.................................................           22.23           17.75           -4.48           18.21           16.07           -2.14
Area....................................................           20.60           20.59           -0.01           53.29           52.70           -0.59
Onroad..................................................           86.58           64.07          -22.51           64.38           47.90          -16.48
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................          238.70          200.32          -38.38          149.96          132.03          -17.93
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Table 7 shows that the Cincinnati-Hamilton area reduced
NOX and VOC emissions by 38.38 TPSD and 17.93 TPSD,
respectively, between 2011 and 2014. As shown in Table 6, the Ohio
portion of the Cincinnati-Hamilton area alone reduced NOX
and VOC emissions by 28.11 TPSD and 16.41 TPSD, respectively, between
2011 and 2014.
3. Meteorology
    To further support Ohio EPA's demonstration that the improvement in
air quality between the year violations occurred and the year
attainment was achieved, is due to permanent and enforceable emission
reductions and not on favorable meteorology, an analysis was performed
by the Lake Michigan Air Directors Consortium (LADCO). A classification
and regression tree (CART) analysis was conducted with 2000 through
2014 data from three Cincinnati-Hamilton area ozone sites. The goal of
the analysis was to determine the meteorological and air quality
conditions associated with ozone episodes, and construct trends for the
days identified as sharing similar meteorological conditions.
    Regression trees were developed for the three monitors to classify
each summer day by its ozone concentration and associated
meteorological conditions. By grouping days with similar meteorology,
the influence of meteorological variability on the underlying trend in
ozone concentrations is partially removed and the remaining trend is
presumed to be due to trends in precursor emissions or other non-
meteorological influences. The CART analysis showed the resulting
trends in ozone concentrations declining over the period examined,
supporting the conclusion that the improvement in air quality was not
due to unusually favorable meteorology.

D. Does Ohio have a fully approvable ozone maintenance plan for the
Cincinnati-Hamilton area?

    As one of the criteria for redesignation to attainment section
107(d)(3)(E)(iv) of the CAA requires EPA to determine that the area has
a fully approved maintenance plan pursuant to section 175A of the CAA.
Section 175A of the CAA sets forth the elements of a maintenance plan
for areas seeking redesignation from nonattainment to attainment. Under
section 175A, the maintenance plan must demonstrate continued
attainment of the NAAQS for at least 10 years after the Administrator
approves a redesignation to attainment. Eight years after the
redesignation, the state must submit a revised maintenance plan which
demonstrates that attainment of the NAAQS will continue for an
additional 10 years beyond the initial 10 year maintenance period. To
address the possibility of future NAAQS violations, the maintenance
plan must contain contingency measures, as EPA deems necessary, to
assure prompt correction of the future NAAQS violation.
    The Calcagni Memorandum provides further guidance on the content of
a maintenance plan, explaining that a maintenance plan should address
five elements: (1) An attainment emission inventory; (2) a maintenance
demonstration; (3) a commitment for continued air quality monitoring;
(4) a process for verification of continued attainment; and (5) a
contingency plan. In conjunction with its request to redesignate the
Ohio portion of the Cincinnati-Hamilton area to attainment for the 2008
ozone standard, Ohio EPA submitted a SIP revision to provide for
maintenance of the 2008 ozone standard through 2030, more than 10 years
after the expected effective date of the redesignation to attainment.
As is discussed more fully below, EPA proposes to find that Ohio's
ozone maintenance plan includes the necessary components and is
proposing to approve the maintenance plan as a revision of the Ohio
SIP.
1. Attainment Inventory
    EPA is proposing to determine that the Cincinnati-Hamilton area has
attained the 2008 8-hour ozone NAAQS based on monitoring data for the
period of 2013-2015. Ohio EPA selected 2014 as the attainment emissions
inventory year to establish attainment emission levels for VOC and
NOX. The attainment emissions inventory identifies the
levels of emissions in the Cincinnati-Hamilton area that are sufficient
to attain the 2008 ozone NAAQS. The derivation of the attainment year
emissions was discussed above in section IV.C.2. of this proposed rule.
The attainment level emissions, by source category, are summarized in
Tables 4 and 5 above.
2. Has the state documented maintenance of the ozone standard in the
Cincinnati-Hamilton area?
    Ohio has demonstrated maintenance of the 2008 ozone standard
through 2030 by assuring that current and future emissions of VOC and
NOX for the Cincinnati-Hamilton area remain at or below
attainment year emission levels. A maintenance demonstration need not
be based on modeling. See Wall v. EPA, 265 F.3d 426 (6th Cir. 2001),
Sierra Club v. EPA, 375 F.3d 537 (7th Cir. 2004). See also 66 FR 53094,
53099-53100 (October 19, 2001), 68 FR 25413, 25430-25432 (May 12,
2003).
    Ohio is using emissions inventories for the years 2020 and 2030 to
demonstrate maintenance. 2030 is more than 10 years after the expected
effective date of the redesignation to attainment and 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.
    To develop the 2020 and 2030 inventories, the state collected data
from the Ozone NAAQS Emissions Modeling platform (2011v6.1) inventories
for years 2011, 2018 and 2025. 2020 emissions for area, nonroad mobile,
AIR, and point source sectors were derived by interpolating between
2018 and 2025. 2030 emissions for area, nonroad mobile, AIR, and point
source sectors were derived using the TREND function in Excel. If the
trend function resulted in a negative value the emissions were assumed
not to change. Summer day inventories were derived for these sectors
using the methodology described in section IV.C.2. above. Finally,
onroad mobile source emissions were developed in conjunction with OKI
using the same methodology described in section IV.C.2. above for the
2011 inventory. Emissions data are shown in Tables 8 through 13 below.

                                Table 8--Cincinnati-Hamilton Area NOX Emissions for Interim Maintenance Year 2020 (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                         County                                Point            AIR           Nonroad          Area           Onroad           Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ohio:
    Butler..............................................            9.77            0.02            2.03            4.78            4.74           21.34
    Clermont............................................           31.32            0.00            1.11            1.14            2.91           36.48
    Clinton.............................................            0.00            0.00            0.64            0.52            1.86            3.02
    Hamilton............................................           18.73            0.02            4.06           10.08           13.05           45.94
    Warren..............................................            1.54            0.00            1.50            1.66            3.81            8.51
Indiana:
    Dearborn............................................            2.96            0.00            0.30            0.48            0.40            4.14
Kentucky:
    Boone...............................................            7.86            2.29            0.60            0.43            2.41           13.59
    Campbell............................................            0.17            0.00            0.23            0.49            1.50            2.39
    Kenton..............................................            0.01            0.00            0.43            1.02            2.28            3.74
                                                         -----------------------------------------------------------------------------------------------
        Ohio Totals.....................................           61.36            0.04            9.34           18.18           26.37          115.29
                                                         -----------------------------------------------------------------------------------------------
            Area Totals.................................           72.36            2.33           10.90           20.60           32.96          139.15
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                Table 9--Cincinnati-Hamilton Area VOC Emissions for Interim Maintenance Year 2020 (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                         County                                Point            AIR           Nonroad          Area           Onroad           Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ohio:
    Butler..............................................            2.98            0.03            2.23            9.38            4.79           19.41

    Clermont............................................            0.51            0.01            1.43            5.28            2.94           10.17
    Clinton.............................................            0.00            0.01            0.51            2.54            0.93            3.99
    Hamilton............................................            2.54            0.04            5.42           21.30           13.18           42.48
    Warren..............................................            0.60            0.01            1.54            5.59            3.85           11.59
Indiana:
    Dearborn............................................            4.06            0.00            0.29            1.77            0.40            6.52
Kentucky:
    Boone...............................................            1.73            0.45            1.03            2.41            1.38            7.00
    Campbell............................................            0.22            0.00            0.25            1.22            0.86            2.55
    Kenton..............................................            0.49            0.00            0.47            2.31            1.30            4.57
                                                         -----------------------------------------------------------------------------------------------
        Ohio Totals.....................................            6.63            0.10           11.13           44.09           25.69           87.64
                                                         -----------------------------------------------------------------------------------------------
            Area Totals.................................           13.13            0.55           13.17           51.80           29.63          108.28
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                    Table 10--Cincinnati-Hamilton Area NOX Emissions for Maintenance Year 2030 (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                         County                                Point            AIR           Nonroad          Area           Onroad           Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ohio:
    Butler..............................................            9.83            0.00            1.16            4.79            2.44           18.22
    Clermont............................................           31.32            0.00            0.63            1.15            1.50           34.60
    Clinton.............................................            0.00            0.00            0.29            0.53            1.28            2.10
    Hamilton............................................           18.75            0.00            2.59           10.10            6.71           38.15
    Warren..............................................            1.54            0.00            0.78            1.67            1.96            5.95
Indiana:
    Dearborn............................................            2.96            0.00            0.18            0.48            0.21            3.83
Kentucky:
    Boone...............................................            8.51            0.29            0.38            0.44            1.05           10.67
    Campbell............................................            0.17            0.00            0.15            0.49            0.65            1.46
    Kenton..............................................            0.01            0.00            0.27            1.02            0.99            2.29
                                                         -----------------------------------------------------------------------------------------------
        Ohio Totals.....................................           61.44            0.00            5.45           18.24           13.89           99.02
                                                         -----------------------------------------------------------------------------------------------
            Area Totals.................................           73.09            0.29            6.43           20.67           16.79          117.27
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                    Table 11--Cincinnati-Hamilton Area VOC Emissions for Maintenance Year 2030 (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                         County                                Point            AIR           Nonroad          Area           Onroad           Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ohio:
    Butler..............................................            3.00            0.01            2.43            9.31            2.88           17.63
    Clermont............................................            0.64            0.00            1.46            5.20            1.77            9.07
    Clinton.............................................            0.01            0.00            0.42            2.61            0.71            3.75
    Hamilton............................................            2.62            0.00            5.87           21.01            7.92           37.42
    Warren..............................................            0.58            0.00            1.51            5.52            2.32            9.93
Indiana:
    Dearborn............................................            4.06            0.00            0.27            1.85            0.24            6.42
Kentucky:
    Boone...............................................            1.73            0.06            0.92            2.36            0.77            5.84
    Campbell............................................            0.21            0.00            0.22            1.19            0.48            2.10
    Kenton..............................................            0.47            0.00            0.50            2.25            0.73            3.95
                                                         -----------------------------------------------------------------------------------------------
        Ohio Totals.....................................            6.85            0.01           11.69           43.65           15.60           77.80
                                                         -----------------------------------------------------------------------------------------------
            Area Totals.................................           13.32            0.07           13.60           51.30           17.82           96.11
--------------------------------------------------------------------------------------------------------------------------------------------------------

               Table 12--Change in NOX and VOC Emissions Between 2014 and 2030 for the Ohio Portion of the Cincinnati-Hamilton Area (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          NOX                                                 VOC
                                                 -------------------------------------------------------------------------------------------------------
                                                                                Net Change                                          Net Change
                                                      2014         2020         2030     (2014-2030)      2014         2020         2030     (2014-2030)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...........................................        76.51        61.36        61.44       -15.07         6.84         6.63         6.85         0.01
AIR.............................................         0.04         0.04         0.00        -0.04         0.10         0.10         0.01        -0.09
Nonroad.........................................        15.47         9.34         5.45       -10.02        13.52        11.13        11.69        -1.83
Area............................................        18.18        18.18        18.24         0.06        44.70        44.09        43.65        -1.05

Onroad..........................................        49.29        26.37        13.89       -35.40        40.76        25.69        15.60       -25.16
                                                 -------------------------------------------------------------------------------------------------------
    Total.......................................       159.49       115.29        99.02       -60.47       105.92        87.64        77.80       -28.12
--------------------------------------------------------------------------------------------------------------------------------------------------------

                     Table 13--Change in NOX and VOC Emissions Between 2014 and 2030 for the Entire Cincinnati-Hamilton Area (TPSD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          NOX                                                 VOC
                                                 -------------------------------------------------------------------------------------------------------
                                                                                Net Change                                          Net Change
                                                      2014         2020         2030     (2014-2030)      2014         2020         2030     (2014-2030)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...........................................        95.80        72.36        73.09       -22.71        14.84        13.13        13.32        -1.52
AIR.............................................         2.11         2.33         0.29        -1.82         0.52         0.55         0.07        -0.45
Nonroad.........................................        17.75        10.90         6.43       -11.32        16.07        13.17        13.60        -2.47
Area............................................        20.59        20.60        20.67         0.08        52.70        51.80        51.30        -1.40
Onroad..........................................        64.07        32.96        16.79       -47.28        47.90        29.63        17.82       -30.08
                                                 -------------------------------------------------------------------------------------------------------
    Total.......................................       200.32       139.15       117.27       -83.05       132.03       108.28        96.11       -35.92
--------------------------------------------------------------------------------------------------------------------------------------------------------

    In summary, the maintenance demonstration for the Cincinnati-
Hamilton area shows maintenance of the 2008 ozone standard by providing
emissions information to support the demonstration 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 13 shows NOX and
VOC emissions in the Cincinnati-Hamilton area are projected to decrease
by 83.05 TPSD and 35.92 TPSD, respectively, between 2014 and 2030. As
shown in Table 12, NOX and VOC emissions in the Ohio portion
of the Cincinnati-Hamilton area alone are projected to decrease by
60.47 TPSD and 28.12 TPSD, respectively, between 2014 and 2030.
3. Continued Air Quality Monitoring
    Ohio EPA has committed to continue to operate the ozone monitors
listed in Table 1 above. Ohio EPA has committed to consult with EPA
prior to making changes to the existing monitoring network should
changes become necessary in the future. Ohio remains obligated to meet
monitoring requirements and continue to quality assure monitoring data
in accordance with 40 CFR part 58, and to enter all data into the Air
Quality System (AQS) in accordance with Federal guidelines.
4. Verification of Continued Attainment
    The State of Ohio, has the legal authority to enforce and implement
the requirements of the maintenance plan for the Ohio portion of the
Cincinnati-Hamilton 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. Ohio EPA will continue to
operate the current ozone monitors located in the Ohio portion of the
Cincinnati-Hamilton area. There are no plans to discontinue operation,
relocate, or otherwise change the existing ozone monitoring network
other than through revisions in the network approved by the EPA.
    In addition, to track future levels of emissions, Ohio EPA will
continue to develop and submit to EPA updated emission inventories for
all source categories at least once every three years, consistent with
the requirements of 40 CFR part 51, subpart A, and in 40 CFR 51.122.
The Consolidated Emissions Reporting Rule (CERR) was promulgated by EPA
on June 10, 2002 (67 FR 39602). The CERR was replaced by the Annual
Emissions Reporting Requirements (AERR) on December 17, 2008 (73 FR
76539). The most recent triennial inventory for Ohio was compiled for
2014. Point source facilities covered by Ohio's emission statement
rule, Ohio Administrative Code Chapter 3745-24, will continue to submit
VOC and NOX emissions on an annual basis.
5. What is the contingency plan for the Cincinnati-Hamilton area?
    Section 175A of the CAA requires that the state must adopt a
maintenance plan, as a SIP revision, that includes such contingency
measures as EPA deems necessary to assure that the state will promptly
correct a violation of the NAAQS that occurs after redesignation of the
area to attainment of the NAAQS. The maintenance plan must identify:
The contingency measures to be considered and, if needed for
maintenance, adopted and implemented; a schedule and procedure for
adoption and implementation; and, a time limit for action by the state.
The state should also identify specific indicators to be used to
determine when the contingency measures need to be considered, adopted,
and implemented. The maintenance plan must include a commitment that
the state will implement all measures with respect to the control of
the pollutant that were contained in the SIP before redesignation of
the area to attainment in accordance with section 175A(d) of the CAA.
    As required by section 175A of the CAA, Ohio has adopted a
contingency plan for the Cincinnati-Hamilton area to address possible
future ozone air quality problems. The contingency plan adopted by Ohio
has two levels of

response, a warning level response and an action level response.
    In Ohio's plan, a warning level response will be triggered when an
annual fourth high monitored value of 0.079 ppm or higher is monitored
within the maintenance area. A warning level response will consist of
Ohio EPA conducting a study to determine whether the ozone value
indicates a trend toward higher ozone values or whether emissions
appear to be increasing. The studies will evaluate whether the trend,
if any, is likely to continue and, if so, the control measures
necessary to reverse the trend. The studies will consider ease and
timing of implementation as well as economic and social impacts.
Implementation of necessary controls in response to a warning level
response trigger will take place within 12 months from the conclusion
of the most recent ozone season.
    In Ohio's plan, an action level response is triggered when a two-
year average fourth high value of 0.076 ppm or greater is monitored
within the maintenance area. A violation of the standard within the
maintenance area also triggers an action level response. When an action
level response is triggered, Ohio EPA, in conjunction with the
metropolitan planning organization or regional council of governments,
will determine what additional control measures are needed to assure
future attainment of the ozone standard. Control measures selected will
be adopted and implemented within 18 months from the close of the ozone
season that prompted the action level. Ohio EPA may also consider if
significant new regulations not currently included as part of the
maintenance provisions will be implemented in a timely manner and would
thus constitute an adequate contingency measure response.
    Ohio EPA included the following list of potential contingency
measures in its maintenance plan:

    1. Implementation of an enhanced I/M program (E-Check) in
Butler, Clermont, Hamilton and Warren Counties.
    2. Tighten or adopt VOC RACT on existing sources covered by EPA
Control Technique Guidelines issued after the 1990 CAA.
    3. Apply VOC RACT to smaller existing sources.
    4. One or more transportation control measures sufficient to
achieve at least half a percent reduction in actual area wide VOC
emissions. Transportation measures will be selected from the
following, based upon the factors listed above after consultation
with affected local governments:
    a. Trip reduction programs, including, but not limited to,
employer-based transportation management plans, area wide rideshare
programs, work schedule changes, and telecommuting;
    b. traffic flow and transit improvements; and
    c. other new or innovative transportation measures not yet in
widespread use that affected local governments deem appropriate.
    5. Alternative fuel and diesel retrofit programs for fleet
vehicle operations.
    6. Require VOC or NOX emission offsets for new and
modified major sources.
    7. Increase the ratio of emission offsets required for new
sources.
    8. Require VOC or NOX controls on new minor sources
(less than 100 tons).
    9. Adopt NOX RACT for existing combustion sources.

    EPA has concluded that the maintenance plan adequately addresses
the five basic components of a maintenance plan: Attainment inventory,
maintenance demonstration, monitoring network, verification of
continued attainment, and a contingency plan. In addition, as required
by section 175A(b) of the CAA, Ohio EPA has committed to submit to EPA
an updated ozone maintenance plan eight years after redesignation of
the Ohio portion of the Cincinnati-Hamilton area to cover an additional
ten years beyond the initial 10 year maintenance period. Thus, EPA
proposes to find that the maintenance plan SIP revision submitted by
Ohio EPA for the Ohio portion of the Cincinnati-Hamilton area meets the
requirements of section 175A of the CAA.

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

A. Motor Vehicle Emission Budgets

    Under section 176(c) of the CAA, new transportation plans,
programs, or projects that receive Federal funding or support, such as
the construction of new highways, must ``conform'' to (i.e., be
consistent with) the SIP. Conformity to the SIP means that
transportation activities will not cause new air quality violations,
worsen existing air quality problems, or delay timely attainment of the
NAAQS or interim air quality milestones. Regulations at 40 CFR part 93
set forth EPA policy, criteria, and procedures for demonstrating and
assuring conformity of transportation activities to a SIP.
Transportation conformity is a requirement for nonattainment and
maintenance areas. Maintenance areas are areas that were previously
nonattainment for a particular NAAQS, but that have been redesignated
to attainment with an approved maintenance plan for the NAAQS.
    Under the CAA, states are required to submit, at various times,
control strategy SIPs for nonattainment areas and maintenance plans for
areas seeking redesignations to attainment of the ozone standard and
maintenance areas. See the SIP requirements for the 2008 ozone standard
in EPA's March 6, 2015 implementation rule (80 FR 12264). 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. See 40 CFR 93.101.
    Under 40 CFR part 93, a MVEB for an area seeking a redesignation to
attainment must be established, at minimum, for the last year of the
maintenance plan. A state may adopt MVEBs for other years as well. The
MVEB serves as a ceiling on emissions from an area's planned
transportation system. The MVEB concept is further explained in the
preamble to the November 24, 1993, Transportation Conformity Rule (58
FR 62188). The preamble also describes how to establish the MVEB in the
SIP and how to revise the MVEB, if needed, subsequent to initially
establishing a MVEB in the SIP.

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

    Whan reviewing submitted control strategy SIPs or maintenance plans
containing MVEBs, 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 in 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). Additional
information on the adequacy process for transportation conformity
purposes is available in the proposed rule titled, ``Transportation
Conformity Rule Amendments: Response to Court Decision and Additional
Rule Changes,'' 68 FR 38974, 38984 (June 30, 2003).
    As discussed earlier, Ohio's maintenance plan includes
NOX and VOC MVEBs for the Cincinnati-Hamilton area for 2030
and 2020, the last year of the maintenance period and an interim year.
EPA reviewed the VOC and NOX MVEBs through the adequacy
process. Ohio's April 21, 2016, maintenance plan SIP submission,
including the VOC and NOX MVEBs for the Ohio and Indiana
portion of the Cincinnati-Hamilton area was open for public comment on
EPA's adequacy Web site on July 22, 2016, found at: http://www.epa.gov/otaq/stateresources/transconf/currsips.htm. The EPA public comment
period on adequacy of the 2020 and 2030 MVEBs for the Ohio and Indiana
portion of the Cincinnati-Hamilton area closed on August 22, 2016. 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 (or his or her designee) and was subject to a
state public hearing. The MVEBS were developed as part of an
interagency consultation process which includes Federal, state, and
local agencies. The MVEBS were clearly identified and precisely
quantified. These MVEBs, when considered together with all other
emissions sources, are consistent with maintenance of the 2008 8-hour
ozone standard.

                                 Table 14--MVEBs for the Ohio and Indiana Portion of the Cincinnati-Hamilton Area, TPSD
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Attainment         2020                                            2030
                                             year 2014       Estimated      2020 Mobile                      Estimated      2030 Mobile
                                              onroad          onroad       safety margin    2020 MVEBs        onroad       safety margin    2030 MVEBs
                                             emissions       emissions      allocation                       emissions      allocation
--------------------------------------------------------------------------------------------------------------------------------------------------------
VOC.....................................           41.40           26.09            3.91           30.00           15.84            2.38           18.22
NOX.....................................           50.03           26.77            4.02           30.79           14.10            2.12           16.22
--------------------------------------------------------------------------------------------------------------------------------------------------------

    As shown in Table 14, the 2020 and 2030 MVEBs exceed the estimated
2020 and 2030 onroad sector emissions. In an effort to accommodate
future variations in travel demand models and vehicle miles traveled
forecast, Ohio EPA allocated a portion of the safety margin (described
further below) to the mobile sector. Ohio has demonstrated that the
Cincinnati-Hamilton area can maintain the 2008 ozone NAAQS with mobile
source emissions in the Ohio and Indiana portion of the area of 30.00
TPSD and 18.22 TPSD of VOC and 26.77 TPSD and 16.22 TPSD of
NOX in 2020 and 2030, respectively, since despite partial
allocation of the safety margin, emissions will remain under attainment
year emission levels. EPA, has found adequate and is proposing to
approve the MVEBs for use to determine transportation conformity in the
Ohio and Indiana portion of the Cincinnati-Hamilton area, because EPA
has determined that the area can maintain attainment of the 2008 ozone
NAAQS for the relevant maintenance period with mobile source emissions
at the levels of the MVEBs.

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 12, the
emissions in the Ohio portion of the Cincinnati-Hamilton area are
projected to have safety margins of 60.47 TPSD for NOX and
28.12 TPSD for VOC in 2030 (the difference between the attainment year,
2014, emissions and the projected 2030 emissions for all sources in the
Ohio portion of the Cincinnati-Hamilton area). Similarly, there is a
safety margin of 44.20 TPSD for NOX and 18.28 TPSD for VOC
in 2020. Even if emissions reached the full level of the safety margin,
the counties would still demonstrate maintenance since emission levels
would equal those in the attainment year.
    As shown in Table 14 above, Ohio is allocating a portion of that
safety margin to the mobile source sector. Specifically, in 2020, Ohio
is allocating 3.91 TPSD and 4.02 TPSD of the VOC and NOX
safety margins, respectively. In 2030, Ohio is allocating 2.38 TPSD and
2.12 TPSD of the VOC and NOX safety margins, respectively.
Ohio EPA is not requesting allocation to the MVEBs of the entire
available safety margins reflected in the demonstration of maintenance.
In fact, the amount allocated to the MVEBs represents only a small
portion of the 2020 and 2030 safety margins. Therefore, even though the
State is requesting MVEBs that exceed the projected onroad mobile
source emissions for 2020 and 2030 contained in the demonstration of
maintenance, the increase in onroad mobile source emissions that can be
considered for transportation conformity purposes is well within the
safety margins of the ozone maintenance demonstration. Further, once
allocated to mobile sources, these safety margins will not be available
for use by other sources.

VI. Proposed Actions

    EPA is proposing to determine that the Cincinnati-Hamilton
nonattainment is attaining the 2008 ozone standard, based on quality-
assured and certified monitoring data for 2013-2015 and that the Ohio
portion of this area has met the requirements for redesignation under
section 107(d)(3)(E) of the CAA. EPA is thus proposing to approve Ohio
EPA's request to change the legal designation of the Ohio portion of
the Cincinnati-Hamilton area from nonattainment to attainment for the
2008 ozone standard. EPA is also proposing to approve, as a revision to
the Ohio SIP, the state's maintenance plan for the area. The
maintenance plan is designed to keep the Cincinnati-Hamilton area in
attainment of the 2008 ozone NAAQS through 2030. Finally, EPA finds
adequate and is proposing to approve the newly-established 2020 and
2030 MVEBs for the Indiana and Ohio portion of the Cincinnati-Hamilton
area.

VII. Statutory and Executive Order Reviews

    Under the CAA, redesignation of an area to attainment and the
accompanying approval of a maintenance plan under section 107(d)(3)(E)
are actions that affect the

status of a geographical area and do not impose any additional
regulatory requirements on sources beyond those imposed by state law. A
redesignation to attainment does not in and of itself create any new
requirements, but rather results in the applicability of requirements
contained in the CAA for areas that have been redesignated to
attainment. Moreover, the Administrator is required to approve a SIP
submission that complies with the provisions of the CAA and applicable
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in
reviewing SIP submissions, EPA's role is to approve state choices,
provided that they meet the criteria of the CAA. Accordingly, this
action merely approves state law as meeting Federal requirements and
does not impose additional requirements beyond those imposed by state
law. For that reason, this action:
     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);
     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 Section 12(d) of the
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272
note) because application of those requirements would be inconsistent
with the CAA; and
     Does not provide EPA with the discretionary authority to
address, as appropriate, disproportionate human health or environmental
effects, using practicable and legally permissible methods, under
Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, the SIP is not approved to apply on any Indian
reservation land or in any other area where EPA or an Indian tribe has
demonstrated that a tribe has jurisdiction. In those areas of Indian
country, this rule does not have tribal implications as specified by
Executive Order 13175 (65 FR 67249, November 9, 2000), because
redesignation is an action that affects the status of a geographical
area and does not impose any new regulatory requirements on tribes,
impact any existing sources of air pollution on tribal lands, nor
impair the maintenance of ozone national ambient air quality standards
in tribal lands.

List of Subjects in 40 CFR Part 52

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

    Dated: September 19, 2016.
Robert A. Kaplan,
Acting Regional Administrator, Region 5.
[FR Doc. 2016-23301 Filed 9-27-16; 8:45 am]
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