[Federal Register Volume 82, Number 2 (Wednesday, January 4, 2017)]
[Proposed Rules]
[Pages 792-805]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-31635]


=======================================================================
-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R05-OAR-2016-0479; FRL-9957-60-Region 5]


Air Plan Approval; Ohio; Redesignation of the Ohio Portion of the 
Cincinnati-Hamilton, OH-IN-KY Area to Attainment of the 1997 Annual 
Standard for Fine Particulate Matter

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

-----------------------------------------------------------------------

SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
redesignate the Ohio portion of the Cincinnati-Hamilton, OH-IN-KY, 
nonattainment area (hereafter, ``the Cincinnati-Hamilton area'') to 
attainment for the 1997 fine particulate matter (PM2.5) 
annual national ambient air quality standards (NAAQS or standard). The 
Ohio portion of the Cincinnati-Hamilton area includes Butler, Clermont, 
Hamilton, and Warren Counties. Because EPA has determined that the 
Cincinnati-Hamilton area is attaining the annual PM2.5 
standard, EPA is proposing to redesignate the area to attainment and 
also proposing several additional related actions. EPA is proposing to 
approve the Reasonably Available Control Measures (RACM)-Reasonably 
Available Control Technology (RACT) portion of Ohio's Cincinnati-
Hamilton area attainment plan SIP revision as providing adequate RACM/
RACT. EPA is proposing to approve an update to the Ohio state 
implementation plan (SIP), by updating the state's approved plan for 
maintaining the 1997 annual PM2.5 NAAQS through 2027. EPA 
previously approved the base year emissions inventory for the 
Cincinnati-Hamilton area, and is proposing to approve Ohio's updated 
emission inventory which includes emission inventories for volatile 
organic compounds (VOCs) and ammonia. Ohio's approved maintenance plan 
submission includes a budget for the mobile source contribution of 
PM2.5 and nitrogen oxides (NOX) to the 
Cincinnati-Hamilton Ohio PM2.5 area for transportation 
conformity purposes, which EPA is proposing to approve and update. EPA 
is proposing to take these actions in accordance with the Clean Air Act 
(CAA) and EPA's implementation rule regarding the 1997 PM2.5 
NAAQS.

DATES: Comments must be received on or before February 3, 2017.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R05-
OAR-2016-0479 at http://www.regulations.gov, or via email to 
[email protected]. 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: Joseph Ko, Environmental Engineer, 
Attainment Planning and Maintenance Section, Air Programs Branch (AR-
18J), Environmental Protection Agency, Region 5, 77 West Jackson 
Boulevard, Chicago, Illinois 60604, (312) 886-7947, [email protected].

SUPPLEMENTARY INFORMATION: This supplementary information section is 
arranged as follows:

Contents

I. Background
II. What are the criteria for redesignation to attainment?
III. What is EPA's analysis of the state's request?
    1. Attainment
    2. Section 110 and Part D Requirements, and Approval SIP under 
Section 110(k) (Section 107(d)(3)(E)(ii) and (v))
    3. Permanent and Enforceable Reductions in Emissions (Section 
107(d)(3)(E)(iii))
    4. Maintenance Plan Pursuant to Section 175A of the CAA (Section 
107(d)(3)(E)(iv))
    5. Motor Vehicle Emissions Budget (MVEBs) for the Mobile Source 
Contribution to PM2.5 and NOX
    6. Comprehensive Emissions Inventory
IV. EPA's Proposed Actions
V. Statutory and Executive Order Reviews

I. Background

    The first air quality standards for PM2.5 were 
promulgated on July 18, 1997, at 62 FR 38652. EPA promulgated an annual 
standard at a level of 15 micrograms per cubic meter ([micro]g/m\3\) of 
ambient air, based on a three-year average of the annual mean 
PM2.5 concentrations at each monitoring site.
    On January 5, 2005, at 70 FR 944, EPA published air quality area 
designations for the 1997 annual PM2.5 standard based on air 
quality data for calendar years 2001-2003. In that rulemaking, EPA 
designated the Cincinnati-Hamilton area (the Ohio portion being Butler, 
Clermont, Hamilton, and Warren Counties) as nonattainment for the 1997 
annual PM2.5 standard.
    In this proposed redesignation, EPA takes into account two 
decisions of the D.C. Circuit. On August 21, 2012, in EME Homer City 
Generation, L.P. v. EPA, 696 F.3d 7 (D.C. Cir. 2012), the D.C. Circuit 
vacated and remanded the Cross State Air Pollution Rule (CSAPR) and 
ordered EPA to continue administering the Clean Air Interstate Rule 
(CAIR) ``pending . . . development of a valid replacement.'' EME Homer 
City at 38. The D.C. Circuit denied all

[[Page 793]]

petitions for rehearing in the case on January 24, 2013. In the second 
decision, on January 4, 2013, the D.C. Circuit remanded to EPA the 
``Final Clean Air Fine Particle Implementation Rule'' (72 FR 20586, 
April 25, 2007) and the ``Implementation of the New Source Review (NSR) 
Program for Particulate Matter Less than 2.5 Micrometers 
(PM2.5)'' final rule (73 FR 28321, May 16, 2008). Natural 
Resources Defense Council v. EPA, 706 F.3d 428 (D.C. Cir. 2013).

II. What are the criteria for redesignation to attainment?

    The CAA sets forth the requirements for redesignating a 
nonattainment area to attainment. Specifically, section 107(d)(3)(E) of 
the CAA allows for redesignation provided that: (1) The Administrator 
determines that the area has attained the applicable NAAQS based on 
current air quality data; (2) the Administrator has fully approved an 
applicable SIP 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 emission reductions resulting from 
implementation of the applicable SIP, Federal air pollution control 
regulations, or other permanent and enforceable emission reductions; 
(4) the Administrator has fully approved a maintenance plan for the 
area 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 purposes of redesignation under section 110 and part D of the 
CAA.

III. What is EPA's analysis of the state's request?

    EPA is proposing to redesignate the Ohio portion of the Cincinnati-
Hamilton area to attainment of the 1997 annual PM2.5 NAAQS, 
and is proposing to approve updates to Ohio's maintenance plan for the 
area and other related SIP revisions. EPA is also proposing to approve 
Ohio's RACM/RACT analysis. The bases for these proposed actions follow.

1. Attainment

    In accordance with section 179(c) of the CAA, 42 U.S.C. 7509(c) and 
40 CFR 51.1004(c), EPA is proposing to determine that the Cincinnati-
Hamilton area has attained the 1997 annual PM2.5 NAAQS. This 
proposed determination is based upon complete, quality-assured, and 
certified ambient air monitoring data for the 2013-2015 monitoring 
period that shows this area has monitored attainment of the 1997 
PM2.5 NAAQS.
    Under EPA's regulations at 40 CFR 50.7, the annual primary and 
secondary PM2.5 standards are met when the annual arithmetic 
mean concentration, as determined in accordance with 40 CFR part 50, 
appendix N, is less than or equal to 15.0 [micro]g/m\3\ at all relevant 
monitoring sites in the area.
    EPA has reviewed the ambient air quality monitoring data in the 
Cincinnati-Hamilton area, consistent with the provisions of 40 CFR part 
50, appendix T. EPA's review focused on data recorded in the EPA Air 
Quality System (AQS) database for the Cincinnati-Hamilton area for 
PM2.5 nonattainment area from 2013-2015.
    The Cincinnati-Hamilton area has nine monitors located in Butler 
(OH), Hamilton (OH), and Campbell (KY) Counties that reported design 
values from 2013-2015 for PM2.5 that ranged from 9.5 to 11.2 
[mu]g/m\3\ for the 1997 annual standard. The data are summarized shown 
in Table 1 below.
    There are three additional monitor sites in Butler County that are 
not listed in Table 1 because the data from these sites are not used 
for redesignation purposes. On October 31, 2014, EPA determined that 
site 39-017-0020 was located within the immediate area of several 
facilities, and that the monitoring data from the site would no longer 
be compared to the annual PM2.5 standard. On February 5, 
2015, monitor site 39-017-0022 in Bulter County became active, but 
since it is a ``special purpose monitor'', it cannot be used for 
comparison to the NAAQS before 24 months, per 40 CFR 58.20. 
Additionally, a new monitor site, 39-017-0016, became active in 2016 
but it was not included in Ohio's analysis because it does not yet have 
three years of valid data.
    All monitors in the Cincinnati-Hamilton area recorded complete data 
in accordance with criteria set forth by EPA in 40 CFR part 50 appendix 
N, where a complete year of air quality data comprises four calendar 
quarters, with each quarter containing data from at least 75% capture 
of the scheduled sampling days. Data available are considered to be 
sufficient for comparison to the NAAQS if three consecutive complete 
years of data exist. Recently the state certified data for 2013-2015 
show the area continues to attain the standard. Partial 2016 data for 
all relevant monitors also support a finding that the area continues to 
attain the standard.

               Table 1--Annual PM2.5 Design Values for the Cincinnati-Hamilton Area for 2013-2015
----------------------------------------------------------------------------------------------------------------
                                                                 Annual design values ([mu]g/m\3\)
                                                 ---------------------------------------------------------------
                   County/Site                                         Year                           Average
                                                 ---------------------------------------------------------------
                                                       2013            2014            2015          2013-2015
----------------------------------------------------------------------------------------------------------------
Butler, OH:
    39-017-0003.................................            11.1            11.3            10.3            10.9
    39-017-0016.................................            10.7            10.7             9.5            10.3
    39-017-0019.................................              11            11.2            10.2            10.8
Hamilton, OH:
    39-061-0006.................................            10.1            10.3             9.3             9.9
    39-061-0014.................................            11.6            11.3            10.7            11.2
    39-061-0040.................................            10.6            10.4             9.2            10.1
    39-061-0042.................................            11.5            11.2            10.1              11
    39-061-0010.................................            10.5            10.4             9.2              10
Campbell, KY:
    21-037-3002.................................             9.6             9.7           9.4 *             9.5
----------------------------------------------------------------------------------------------------------------
* less than 75% capture in one quarter at the primary monitor, but substitution using a secondary monitor was
  completed resulting in an AQS 'valid' design value.


[[Page 794]]

    Based on the information summarized above, EPA has found that the 
Cincinnati-Hamilton area has attained the 1997 annual PM2.5 
NAAQS.

2. Section 110 and Part D Requirements, and Approval SIP Under Section 
110(k) (Section 107(d)(3)(E)(ii) and (v))

    We have determined that, under section 110 of the CAA (general SIP 
requirements), Ohio has met all currently applicable SIP requirements 
for purposes of redesignation for the Cincinnati-Hamilton area. We are 
also proposing to find, in accordance with section 107(d)(3)(E)(v), 
that the Ohio submittal meets all SIP requirements currently applicable 
for purposes of redesignation under part D of title I of the CAA. In 
addition, we are proposing to find, in accordance with section 
107(d)(3)(E)(ii), that all applicable requirements of the Ohio SIP for 
purposes of redesignation have been approved. As discussed above, EPA 
previously approved Ohio's 2005 emissions inventory as meeting the 
section 172(c)(3) comprehensive emissions inventory requirement.
    In making these proposed determinations, we have ascertained which 
SIP requirements are applicable for purposes of redesignation, and 
concluded that the Ohio SIP includes measures meeting those 
requirements and that they are fully approved under section 110(k) of 
the CAA.
a. Section 110 General SIP Requirements
    Section 110(a) of title I of the CAA contains the general 
requirements for a SIP. Section 110(a)(2) provides that the 
implementation plan submitted by a state must have been adopted by the 
state after reasonable public notice and hearing, and, among other 
things, must: Include enforceable emission limitations and other 
control measures, means or techniques necessary to meet the 
requirements of the CAA; provide for establishment and operation of 
appropriate devices, methods, systems, and procedures necessary to 
monitor ambient air quality; provide for implementation of a source 
permit program to regulate the modification and construction of any 
stationary source within the areas covered by the plan; include 
provisions for the implementation of part C, Prevention of Significant 
Deterioration (PSD) and part D, NSR permit programs; include criteria 
for stationary source emission control measures, monitoring, and 
reporting; include provisions for air quality modeling; and provide for 
public and local agency participation in planning and emission control 
rule development.
    Section 110(a)(2)(D) of the CAA requires that SIPs contain measures 
to prevent sources in a state from significantly contributing to air 
quality problems in another state. EPA believes that the requirements 
linked with a particular nonattainment area's designation are the 
relevant measures to evaluate in reviewing a redesignation request. The 
transport SIP submittal requirements, where applicable, continue to 
apply to a state regardless of the designation of any one particular 
area in the state. Thus, we believe that these requirements should not 
be construed as the applicable requirements for purposes of 
redesignation.
    Further, we believe that the other section 110 elements described 
above that are not connected with nonattainment plan submissions and 
not linked with an area's attainment status are not applicable 
requirements for purposes of redesignation. A state remains subject to 
these requirements after an area is redesignated to attainment. We 
conclude that only the section 110 and part D requirements that are 
linked with a particular area's designation are the relevant measures 
which we may consider in evaluating a redesignation request. See 
Reading, Pennsylvania, proposed and final rulemakings (61 FR 53174-
53176, October 10, 1996) and (62 FR 24826, May 7, 1997); Cleveland-
Akron-Lorain, Ohio, final rulemaking (61 FR 20458, May 7, 1996); and 
Tampa, Florida, final rulemaking (60 FR 62748, December 7, 1995). See 
also the discussion on this issue in the Cincinnati, Ohio 1-hour ozone 
redesignation (65 FR 37890, June 19, 2000), and in the Pittsburgh, 
Pennsylvania 1-hour ozone redesignation (66 FR 50399, October 19, 
2001).
    We have reviewed the Ohio SIP and have concluded that it meets the 
general SIP requirements under section 110 of the CAA to the extent 
they are applicable for purposes of redesignation. EPA has previously 
approved provisions of Ohio's SIP addressing section 110 requirements 
(including provisions addressing particulate matter), at 40 CFR 
52.1870.
    On December 5, 2007, Ohio made a submittal addressing 
``infrastructure SIP'' elements required under CAA section 110(a)(2). 
EPA proposed approval of the December 5, 2007, submittal on April 28, 
2011, at 76 FR 23757 and published final approval on July 13, 2011, at 
76 FR 41075.
    The remaining parts of the infrastructure SIPs required by section 
110(a)(2) are not relevant to this redesignation, and are statewide 
requirements that are not linked to the PM2.5 nonattainment 
status of the Cincinnati-Hamilton area. Therefore, EPA believes that 
these SIP elements are not applicable requirements for purposes of 
review of the state's PM2.5 redesignation request.
b. Part D Requirements
    EPA has determined that, upon approval of the base year emissions 
inventories discussed in section III.6 of this rulemaking, the Ohio SIP 
will meet the applicable SIP requirements for the Cincinnati-Hamilton 
area applicable for purposes of redesignation under part D of the CAA. 
Subpart 1 of part D, found in sections 172-176 of the CAA, sets forth 
the basic nonattainment requirements applicable to all nonattainment 
areas. Subpart 4 of part D, found in sections 189 of the CAA, sets 
forth nonattainment requirements applicable for particulate matter 
nonattainment areas.
(i) RACM/RACT Requirements Under Section 172(c)(1)
    Section 172(c)(1) requires that each attainment plan ``provide for 
the implementation of all reasonably available control measures as 
expeditiously as practicable (including such reductions in emissions 
from the existing sources in the area as may be obtained through the 
adoption, at a minimum, of reasonably available control technology), 
and shall provide for attainment of the national primary ambient air 
quality standards.'' The PM2.5 Implementation Rule (72 FR 
20586) requires that the subpart 1 RACM portion of the attainment plan 
SIP revision include the list of potential measures that a state 
considered and additional information sufficient to show that the state 
has met all requirements for the determination of what constitutes RACM 
in a specific nonattainment area. See 40 CFR 51.1010(a). Any measures 
that are necessary to meet these requirements that are not already 
either federally promulgated, part of the SIP, or otherwise creditable 
in SIPs must be submitted in enforceable form as part of a state's 
attainment plan SIP revision for the area.
    In 1972, 1980, and 1991, Ohio promulgated RACM rules for 
particulate emissions from stationary sources. Ohio also has RACT rules 
found in OAC Chapter 3745-17. Lake Michigan Air Directors Consortium 
(LADCO), in consultation with two contractors, performed a series of 
studies exploring control measures for reducing both

[[Page 795]]

ozone precursors and PM2.5 precursors in Ohio, Illinois, 
Indiana, Michigan, and Wisconsin. Photochemical modeling was then 
conducted to assess the air quality benefits of the candidate control 
measures. In its attainment demonstration submitted on July 18, 2008, 
Ohio demonstrated that attainment would be achieved in the Cincinnati-
Hamilton area by 2009, based on the modeling conducted by the LADCO 
project team. Because of the projected 2009 attainment date, it would 
not have been reasonably possible or practicable for Ohio to develop 
RACM/RACT requirements, promulgate regulations and implement a control 
program prior to 2009. Ohio concluded that its RACM/RACT analysis, 
based on LADCO modeling, demonstrates that current control measures in 
Ohio satisfy RACM/RACT for the 1997 annual PM2.5 standard.
    EPA has reviewed Ohio's RACM/RACT analysis and agrees that it 
indicates that no other reasonably available measures were available, 
or necessary, to attain or advance attainment of the standard. Because 
Ohio has demonstrated with modeling that no further control measures 
would advance the attainment date in the area, EPA is proposing to 
approve Ohio's RACM/RACT portion of the attainment plan SIP revision as 
providing adequate RACM/RACT consistent with the provisions of 40 CFR 
51.1010(b).
    EPA previously redesignated the Cincinnati-Hamilton area to 
attainment for the 1997 annual PM2.5 standard, predicated in 
part on a finding that the RACM/RACT requirement (interpreted as 
reflecting those reasonable measures needed to attain the standard) was 
not an applicable requirement for purposes of redesignation of areas 
already meeting the standard. EPA has long interpreted that subpart 1 
nonattainment planning requirements, including RACM, are not 
``applicable for purposes of section 107(d)(3)(E)(ii) and (v) when an 
area is attaining the NAAQS, and, therefore, need not be approved into 
the SIP before EPA can redesignate the area. See 76 FR 80258.
    On July 14, 2015, the United States Court of Appeals for the Sixth 
Circuit (Sixth Circuit) issued an opinion in Sierra Club v. EPA, 793 
F.3d 656 (6th Cir. 2015), vacating EPA's redesignation of the Indiana 
and Ohio portions of the Cincinnati-Hamilton area to attainment for the 
1997 PM2.5 NAAQS on the basis that EPA had not approved 
subpart 1 RACM for the area into the SIP.\1\ The Sixth Circuit vacated 
the redesignation of the Ohio and Indiana portion of the area based on 
its view that RACM/RACT must be considered an applicable requirement 
for designation purposes. Consistent with that ruling, EPA is now 
finding that Ohio has satisfied this applicable requirement.
---------------------------------------------------------------------------

    \1\ The Court issued its initial decision in the case on March 
18, 2015, and subsequently issued an amended opinion on July 14 
after appeals for rehearing en banc and panel rehearing had been 
filed. The amended opinion revised some of the legal aspects of the 
Court's analysis of the relevant statutory provisions (section 
107(d)(3)(E)(ii) and section 172(c)(1)), but the overall holding of 
the opinion was unaltered. On March 28, 2016, the Supreme Court 
denied a petition for certiorari from Ohio requesting review of the 
Sixth Circuit's decision.
---------------------------------------------------------------------------

(ii) Other Section 172 Requirements
    For purposes of evaluating this redesignation request, the 
applicable section 172 SIP requirements for the Cincinnati-Hamilton 
area are contained in sections 172(c)(1)-(9). A thorough discussion of 
the requirements contained in section 172 can be found in the General 
Preamble for Implementation of Title I (57 FR 13498, April 16, 1992).
    Under section 172, states with nonattainment areas must submit 
plans providing for timely attainment and meeting a variety of other 
requirements. However, pursuant to 40 CFR 51.1004(c), EPA's 
determination that the area has attained the 1997 annual 
PM2.5 standard suspends the requirement to submit certain 
planning SIPs related to attainment, including: Attainment 
demonstration requirements, the RFP and attainment demonstration 
requirements of sections 172(c)(2) and (6) and 182(b)(1) of the CAA, 
and the requirement for contingency measures of section 172(c)(9) of 
the CAA.
    As a result, the only remaining requirements under section 172 to 
be considered are the emissions inventory requirement under section 
172(c)(3), and the RACM/RACT requirement of section 172(c)(1) per the 
6th circuit decision. As discussed previously, EPA is proposing to 
approve the VOCs and ammonia emissions inventories that Ohio submitted 
as satisfying the section 172(c)(3) requirement, and existing control 
measures as satisfying RACM/RACT requirements under section 172(c)(1).
    No SIP provisions applicable for redesignation of the Cincinnati-
Hamilton area are currently disapproved, conditionally approved, or 
partially approved. Ohio currently has a fully approved SIP for all 
requirements, as applicable for purposes of redesignation under the 
Sixth Circuit's Sierra Club decision.
    Section 172(c)(1) requires the plans for all nonattainment areas to 
provide for the implementation of RACM as expeditiously as practicable 
and to provide for attainment of the primary NAAQS. EPA interprets this 
requirement to impose a duty on all states to consider all available 
control measures for all nonattainment areas and to adopt and implement 
such measures as are reasonably available for implementation in each 
area as components of the area's attainment demonstration.
    As noted above in the previous section, the Sixth Circuit concluded 
that ``a State seeking redesignation `shall provide for the 
implementation' of RACM/RACT, even if those measures are not strictly 
necessary to demonstrate attainment with the PM2.5 NAAQS. . 
. . If a State has not done so, EPA cannot `fully approve[]' the area's 
SIP, and redesignation to attainment status is improper.'' Sierra Club, 
793 F.3d at 670.
    EPA is adhering to the Sixth Circuit's decision. Ohio has 
demonstrated that no further control measures would be necessary to 
advance the attainment date in the Cincinnati-Hamilton area, and EPA is 
proposing to approve existing control measures as satisfying RACM/RACT 
requirements under section 172(c)(1). A further discussion on RACM/RACT 
requirements can be found in the previous section entitled ``RACM/RACT 
Requirements Under Section 172(c)(1).''
    The reasonable further progress (RFP) requirement under section 
172(c)(2) is defined as progress that must be made toward attainment. 
This requirement is not relevant for purposes of the Cincinnati-
Hamilton redesignation because the area has monitored attainment of the 
1997 annual PM2.5 NAAQS. (General Preamble, 57 FR 13564). 
See also 40 CFR 51.918. The requirement to submit the section 172(c)(9) 
contingency measures is similarly not applicable for purposes of 
redesignation. Id.
    Section 172(c)(3) requires submission and approval of a 
comprehensive, accurate and current inventory of actual emissions. Ohio 
submitted a 2005 base year emissions inventory in the required 
attainment plan, and also updated the emissions inventory with VOCs and 
ammonia emissions from 2007. EPA previously approved the 2005 base year 
emissions inventory (76 FR 64825), and is proposing to approve the 
emissions inventory for VOCs and ammonia.
    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

[[Page 796]]

stationary sources anywhere in the nonattainment area. EPA approved 
Ohio's current NSR program on January 10, 2003 (68 FR 1366), but has 
not approved updates since that time. Nonetheless, since PSD 
requirements will apply after redesignation, the area need not have a 
fully-approved NSR program for purposes of redesignation, provided that 
the area demonstrates maintenance of the NAAQS without part D NSR. A 
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, 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. 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).
    Section 172(c)(6) requires the SIP to contain control measures 
necessary to provide for attainment of the standard. 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 have found that 
Ohio's SIP meets the applicable requirements of section 110(a)(2) for 
purposes of redesignation.
(iii) Section 176 Conformity Requirements
    Section 176(c) of the CAA requires states to establish criteria and 
procedures to ensure that Federally-supported or funded activities, 
including highway projects, conform to the air quality planning goals 
in the applicable SIPs. The requirement to determine conformity applies 
to transportation plans, programs and projects developed, funded or 
approved under Title 23 of the U.S. Code and the Federal Transit Act 
(transportation conformity) as well as to all other Federally-supported 
or funded projects (general conformity). State transportation 
conformity regulations must be consistent with Federal conformity 
regulations relating to consultation, enforcement, and enforceability, 
which EPA promulgated pursuant to CAA requirements.
    EPA approved Ohio's transportation conformity SIPs on March 2, 2015 
(80 FR 11134). In April 2010, EPA promulgated changes to 40 CFR 51.851, 
eliminating the requirement for states to maintain a general conformity 
SIP. Following this promulgation, EPA granted Ohio's request to remove 
its general conformity regulations from the SIP. See 80 FR 29968. EPA 
confirms that Ohio has met the applicable conformity requirements under 
section 176.
(iv) Subpart 4
    On January 4, 2013, in Natural Resources Defense Council v. EPA, 
the D.C. Circuit remanded to EPA the ``Final Clean Air Fine Particle 
Implementation Rule'' (72 FR 20586, April 25, 2007) and the 
``Implementation of the New Source Review (NSR) Program for Particulate 
Matter Less than 2.5 Micrometers (PM2.5)'' final rule (73 FR 
28321, May 16, 2008) (collectively, ``1997 PM2.5 
Implementation Rule''). 706 F.3d 428 (D.C. Cir. 2013). The Court found 
that EPA erred in implementing the 1997 PM2.5 NAAQS pursuant 
to the general implementation provisions of subpart 1 of part D of 
title I of the CAA, rather than the particulate-matter-specific 
provisions of subpart 4 of part D of title I.
    EPA has longstanding general guidance that interprets the 1990 
amendments to the CAA, making recommendations to states for meeting the 
statutory requirements for SIPs for nonattainment areas. See, ``State 
Implementation Plans; General Preamble for the Implementation of Title 
I of the Clear Air Act Amendments of 1990,'' 57 FR 13498 (April 16, 
1992) (the ``General Preamble''). In the General Preamble, EPA 
discussed the relationship of subpart 1 and subpart 4 SIP requirements, 
and pointed out that subpart 1 requirements were, to an extent, 
``subsumed by, or integrally related to, the more specific PM-10 
requirements.'' 57 FR 13538 (April 16, 1992). The subpart 1 
requirements include, among other things, provisions for attainment 
demonstrations, RACM, RFP, emissions inventories, and contingency 
measures.
    For the purposes of this redesignation, in order to identify any 
additional requirements which would apply under subpart 4, we are 
considering the Cincinnati-Hamilton area to be a ``moderate'' 
PM2.5 nonattainment area. Under section 188 of the CAA, all 
areas designated nonattainment areas under subpart 4 would initially be 
classified by operation of law as ``moderate'' nonattainment areas, and 
would remain moderate nonattainment areas unless and until EPA 
reclassifies the area as a ``serious'' nonattainment area. Accordingly, 
EPA believes that it is appropriate to limit the evaluation of the 
potential impact of subpart 4 requirements to those that would be 
applicable to moderate nonattainment areas.
    Section 189(a) and (c) of subpart 4 applies to moderate 
nonattainment areas and includes the following: (1) An approved permit 
program for construction of new and modified major stationary sources 
(section 189(a)(1)(A)); (2) an attainment demonstration (section 
189(a)(1)(B)); (3) provisions for RACM (section 189(a)(1)(C)); and (4) 
quantitative milestones demonstrating RFP toward attainment by the 
applicable attainment date (section 189(c)).
    The permit requirements of subpart 4, as contained in section 
189(a)(1)(A), refer to and apply the subpart 1 permit provisions 
requirements of sections 172 and 173 to PM10, without adding 
to them. Consequently, EPA believes that section 189(a)(1)(A) does not 
itself impose for redesignation purposes any additional requirements 
for moderate areas beyond those contained in subpart 1.\2\ In any 
event, in the context of redesignation, EPA has long relied on the 
interpretation that a fully approved nonattainment new source review 
program is not considered an applicable requirement for redesignation, 
provided the area can maintain the standard with a PSD program after 
redesignation. A 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.'' See 
also 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).
---------------------------------------------------------------------------

    \2\ The potential effect of section 189(e) on section 
189(a)(1)(A) for purposes of evaluating this redesignation is 
discussed below.
---------------------------------------------------------------------------

    With respect to the specific attainment planning requirements under 
subpart 4,\3\ when EPA evaluates a redesignation request under subpart 
1 and/or 4, any area that is attaining the PM2.5 standard is 
viewed as having satisfied the attainment planning

[[Page 797]]

requirements for these subparts. For redesignations, EPA has for many 
years interpreted attainment-linked requirements as not applicable for 
areas attaining the standard. In the General Preamble, EPA stated that:
---------------------------------------------------------------------------

    \3\ I.e., attainment demonstration, RFP, RACM, milestone 
requirements, contingency measures.

The requirements for RFP will not apply in evaluating a request for 
redesignation to attainment since, at a minimum, the air quality 
data for the area must show that the area has already attained. 
Showing that the State will make RFP towards attainment will, 
---------------------------------------------------------------------------
therefore, have no meaning at that point.

``General Preamble for the Interpretation of Title I of the CAA 
Amendments of 1990''; (57 FR 13498, 13564, April 16, 1992).
    The General Preamble also explained that:

[t]he section 172(c)(9) requirements are directed at ensuring RFP 
and attainment by the applicable date. These requirements no longer 
apply when an area has attained the standard and is eligible for 
redesignation. Furthermore, section 175A for maintenance plans . . . 
provides specific requirements for contingency measures that 
effectively supersede the requirements of section 172(c)(9) for 
these areas.

Id.
    EPA similarly stated in its September 4, 1992 Calcagni memorandum 
(Calcagni memorandum) that, ``[t]he requirements for reasonable further 
progress and other measures needed for attainment will not apply for 
redesignations because they only have meaning for areas not attaining 
the standard.''
    Elsewhere in this action, EPA proposes to determine that the area 
has attained the 1997 annual PM2.5 standard. Under its 
longstanding interpretation, EPA is proposing to determine here that 
the area meets the attainment-related plan requirements of subparts 1 
and 4. Thus, EPA is proposing to conclude that the requirements to 
submit an attainment demonstration under 189(a)(1)(B), a RACM 
determination under sections 172(c)(1) and 189(a)(1)(c), a RFP 
demonstration under section 189(c)(1), and contingency measure 
requirements under section 172(c)(9) are satisfied for purposes of 
evaluating the redesignation request.
    PM2.5 pollution can be emitted directly from a source 
(primary PM2.5) or formed secondarily through chemical 
reactions in the atmosphere involving precursor pollutants emitted from 
a variety of sources. Sulfates are a type of secondary particulate 
formed from SO2 emissions from power plants and industrial 
facilities. Nitrates, another common type of secondary particulate, are 
formed from combustion emissions of NOX from power plants, 
mobile sources, and other combustion sources.
    CAA section 189(e) specifically provides that control requirements 
for major stationary sources of direct PM10 shall also apply 
to PM10 precursors from those sources, except where EPA 
determines that major stationary sources of such precursors ``do not 
contribute significantly to PM10 levels which exceed the 
standard in the area.''
    For a number of reasons, EPA believes that this proposed 
redesignation of the Cincinnati-Hamilton area is consistent with the 
Court's decision on this aspect of subpart 4. First, while the Court, 
citing section 189(e), stated that ``for a PM10 area 
governed by subpart 4, a precursor is `presumptively regulated,' '' the 
Court expressly declined to decide the specific challenge to EPA's 1997 
PM2.5 implementation rule provisions regarding ammonia and 
VOCs as precursors. The Court had no occasion to reach whether and how 
it was substantively necessary to regulate any specific precursor in a 
particular PM2.5 nonattainment area, and did not address 
what might be necessary for purposes of acting upon a redesignation 
request.
    The Cincinnati-Hamilton area has attained the standard without any 
specific additional controls of VOCs and ammonia emissions from any 
sources in the area.
    Precursors in subpart 4 are specifically regulated under the 
provisions of section 189(e), which requires, with important 
exceptions, control requirements for major stationary sources of 
PM10 precursors.\4\ As explained below, we do not believe 
that any additional controls of ammonia and VOCs are required in the 
context of this redesignation.
---------------------------------------------------------------------------

    \4\ Under either subpart 1 or subpart 4, for purposes of 
demonstrating attainment as expeditiously as practicable, a state is 
required to evaluate all economically and technologically feasible 
control measures for direct PM emissions and precursor emissions, 
and adopt those measures that are deemed reasonably available.
---------------------------------------------------------------------------

    In the General Preamble, EPA discusses its approach to implementing 
section 189(e). See 57 FR 13538-13542. With regard to precursor 
regulation under section 189(e), the General Preamble explicitly stated 
that control of VOCs under other CAA requirements may suffice to 
relieve a state from the need to adopt precursor controls under section 
189(e) (57 FR 13542). EPA proposes to determine that Ohio has met the 
provisions of section 189(e) with respect to ammonia and VOCs as 
precursors. This proposed supplemental determination is based on our 
findings that: (1) The Cincinnati-Hamilton area contains no major 
stationary sources of ammonia, and (2) existing major stationary 
sources of VOCs are adequately controlled under other provisions of the 
CAA regulating the ozone NAAQS.\5\ In the alternative, EPA proposes to 
determine that, under the express exception provisions of section 
189(e), and in the context of the redesignation of the area, which is 
attaining the 1997 annual PM2.5 standard, at present ammonia 
and VOCs precursors from major stationary sources do not contribute 
significantly to levels exceeding the 1997 PM2.5 standard in 
the Cincinnati-Hamilton area. See 57 FR 13539-42.
---------------------------------------------------------------------------

    \5\ The Cincinnati-Hamilton area has reduced VOC emissions 
through the implementation of various SIP approved VOC control 
programs and various on-road and nonroad motor vehicle control 
programs.
---------------------------------------------------------------------------

    EPA notes that its 1997 PM2.5 implementation rule 
provisions in 40 CFR 51.1002 were not directed at evaluation of 
PM2.5 precursors in the context of redesignation, but at SIP 
plans and control measures required to bring a nonattainment area into 
attainment of the 1997 annual PM2.5 NAAQS. By contrast, 
redesignation to attainment primarily requires the area to have already 
attained due to permanent and enforceable emission reductions, and to 
demonstrate that controls in place can continue to maintain the 
standard. Thus, even if we regard the Court's January 4, 2013, decision 
as calling for ``presumptive regulation'' of ammonia and VOCs for 
PM2.5 under the attainment planning provisions of subpart 4, 
those provisions do not require additional controls of these precursors 
for an area that already qualifies for redesignation. Nor does EPA 
believe that requiring Ohio to address precursors differently than it 
has already would result in a different redesignation outcome.
    Although, as EPA has emphasized, its consideration here of 
precursor requirements under subpart 4 is in the context of a 
redesignation to attainment, EPA's existing interpretation of subpart 4 
requirements with respect to precursors in attainment plans for 
PM10 contemplates that states may develop attainment plans 
that regulate only those precursors that are necessary for purposes of 
attainment in the area in question, i.e., states may determine that 
only certain precursors need be regulated for attainment and control 
purposes.\6\ Courts have upheld this

[[Page 798]]

approach to the requirements of subpart 4 for PM10.\7\ EPA 
believes that application of this approach to PM2.5 
precursors under subpart 4 is reasonable. Because the Cincinnati-
Hamilton area has already attained the 1997 annual PM2.5 
NAAQS with its current approach to regulation of PM2.5 
precursors, EPA believes that, in the context of this redesignation, 
there is no need to revisit the attainment control strategy with 
respect to the treatment of precursors. Even if the Court's decision is 
construed to impose an obligation to consider additional precursors 
under subpart 4 in evaluating this redesignation request, it would not 
affect EPA's approval here of Ohio's request for redesignation of the 
Cincinnati-Hamilton area. Moreover, the state has shown, and EPA is 
proposing to determine, that attainment in this area is due to 
permanent and enforceable emissions reductions on all precursors 
necessary to provide for continued attainment. It follows that no 
further control of additional precursors is necessary. Accordingly, EPA 
does not view the January 4, 2013, Court decision as precluding 
redesignation of the Cincinnati-Hamilton area to attainment for the 
1997 PM2.5 NAAQS at this time.
---------------------------------------------------------------------------

    \6\ See, e.g., ``Approval and Promulgation of Implementation 
Plans for California--San Joaquin Valley PM-10 Nonattainment Area; 
Serious Area Plan for Nonattainment of the 24-Hour and Annual PM-10 
Standards,'' 69 FR 30006 (May 26, 2004) (approving a PM10 
attainment plan that impose controls on direct PM10 and 
NOX emissions and did not impose controls on 
SO2, VOC, or ammonia emissions).
    \7\ See, e.g., Assoc. of Irritated Residents v. EPA et al., 423 
F.3d 989 (9th Cir. 2005).
---------------------------------------------------------------------------

    EPA concludes that the area has met all applicable requirements for 
purposes of redesignation in accordance with section 107(d)(3)(E)(ii) 
and (v).
c. Fully Approved Applicable SIP Under Section 110(k) of the CAA
    Upon final approval of Ohio's comprehensive VOCs and ammonia 
emissions inventories, EPA will have fully approved the Ohio SIP for 
the Cincinnati-Hamilton area under section 110(k) of the CAA for all 
requirements applicable for purposes of redesignation. EPA may rely on 
prior SIP approvals in approving a redesignation request (See page 3 of 
the Calcagni memorandum; Southwestern Pennsylvania Growth Alliance v. 
Browner, 144 F.3d 984, 989-990 (6th Cir. 1998); Wall v. EPA, 265 F.3d 
426 (6th Cir. 2001)) plus any additional measures it may approve in 
conjunction with a redesignation action. See 68 FR 25413, 25426 (May 
12, 2003). Since the passage of the CAA of 1970, Ohio has adopted and 
submitted, and EPA has fully approved, provisions addressing various 
required SIP elements under particulate matter standards. In this 
action, EPA is approving Ohio's VOCs and ammonia comprehensive 
emissions inventories for the Cincinnati-Hamilton area as meeting the 
requirement of section 172(c)(3) of the CAA.

3. Permanent and Enforceable Reductions in Emissions (Section 
107(d)(3)(E)(iii))

    EPA believes that Ohio has demonstrated that the observed air 
quality improvement in the Cincinnati-Hamilton area is due to permanent 
and enforceable reductions in emissions resulting from implementation 
of the SIPs, Federal measures, and other state-adopted measures.
    In making this demonstration, Ohio has calculated the change in 
emissions between 2005, one of the years used to designate the area as 
nonattainment, and 2008, one of the years the Cincinnati-Hamilton area 
monitored attainment. 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 contributing areas have implemented, as discussed below.
a. Permanent and Enforceable Controls Implemented
    The following is a discussion of permanent and enforceable measures 
that have been implemented in the area:
i. Federal Emission Control Measures
    Reductions in direct emissions of PM2.5 and in emissions 
of PM2.5 precursors 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. EPA finalized this Federal rule in February 2000. These 
emission control requirements result in lower NOX and 
SO2 emissions from new cars and light duty trucks, including 
sport utility vehicles. Emission standards established under EPA's 
rules became effective between 2004 and 2009. EPA has estimated that, 
emissions of NOX from new vehicles have decreased by the 
following percentages: Passenger cars (light duty vehicles)--77 
percent; light duty trucks, minivans, and sports utility vehicles--86 
percent; and, larger sports utility vehicles, vans, and heavier 
trucks--69 to 95 percent. EPA expects fleet-wide average emissions to 
decline by similar percentages as new vehicles replace older vehicles. 
The Tier 2 standards also reduced the sulfur content of gasoline by up 
to 90 percent. VOCs emissions reductions will be approximately 12 
percent for passenger cars; 18 percent for smaller SUVs, light trucks, 
and minivans; and 15 percent for larger SUVs, vans, and heavier trucks.
    Heavy-Duty Diesel Engine Rule. EPA issued this rule in July 2000. 
This rule, which was phased in between 2004 and 2007, includes 
standards limiting the sulfur content of diesel fuel. This rule is 
estimated to reduce NOX emissions from diesel trucks and 
buses by approximately 40 percent. The level of sulfur in highway 
diesel fuel is also estimated to have dropped by 97 percent by mid-2006 
due to this rule.
    Nonroad Diesel Rule. In May 2004, EPA promulgated a new rule for 
large nonroad diesel engines, such as those used in construction, 
agriculture, and mining equipment, to be phased in between 2008 and 
2014. Prior to 2006, nonroad diesel fuel averaged approximately 3,000 
ppm sulfur. This rule limited nonroad diesel sulfur content to 15 ppm 
by 2010. It is estimated that compliance with this rule has cut 
emissions from nonroad diesel engines by more than 90%. This rule 
achieved some emission reductions by 2008 and was fully implemented by 
2010. The reduction in fuel sulfur content also yielded an immediate 
reduction in sulfate particle emissions from all diesel vehicles.
ii. Control Measures in Contributing Areas
    Given the significance of sulfates and nitrates in the Cincinnati-
Hamilton area, the area's air quality is strongly affected by regulated 
emissions from power plants.
    NOX SIP Call. On October 27, 1998 (63 FR 57356), EPA issued a 
NOX SIP Call requiring the District of Columbia and 22 
states to reduce emissions of NOX. Affected states were 
required to comply with Phase I of the SIP Call beginning in 2004, and 
Phase II beginning in 2007. Emission reductions resulting from 
regulations developed in response to the NOX SIP Call are 
permanent and enforceable.
    CAIR and CSAPR. EPA proposed CAIR on January 30, 2004, at 69 FR 
4566, promulgated CAIR on May 12, 2005, at 70 FR 25162, and promulgated 
associated Federal Implementation Plans (FIPs) on April 28, 2006, at 71 
FR 25328, in order to reduce SO2 and NOX 
emissions and improve air quality in many areas across the Eastern 
United States. However, on July 11, 2008, the United States Court of 
Appeals for the District of Columbia Circuit (D.C. Circuit or Court) 
issued its decision to vacate and remand both CAIR and the associated 
CAIR FIPs in their entirety (North Carolina v. EPA, 531 F.3d 836 (D.C. 
Cir. 2008)). EPA petitioned for a

[[Page 799]]

rehearing, and the Court issued an order remanding CAIR and the CAIR 
FIPs to EPA without vacatur (North Carolina v. EPA, 550 F.3d 1176 (D.C. 
Cir. 2008)). The Court, thereby, left CAIR in place in order to 
``temporarily preserve the environmental values covered by CAIR'' until 
EPA replaced it with a rule consistent with the Court's opinion (id. at 
1178). The Court directed EPA to ``remedy CAIR's flaws'' consistent 
with the July 11, 2008, opinion, but declined to impose a schedule on 
EPA for completing this action (id).
    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. 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.
    Numerous parties filed petitions for review of CSAPR in the D.C. 
Circuit, and on August 21, 2012, the court issued its ruling, vacating 
and remanding CSAPR to EPA and ordering continued implementation of 
CAIR. EME Homer City Generation, L.P. v. EPA, 696 F.3d 7, 38 (D.C. Cir. 
2012). The D.C. Circuit's vacatur of CSAPR was reversed by the United 
States Supreme Court on April 29, 2014, and the case was remanded to 
the D.C. Circuit to resolve remaining issues in accordance with the 
high court's ruling. EPA v. EME Homer City Generation, L.P., 134 S. Ct. 
1584 (2014).
    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) (EME Homer City II). The litigation over CSAPR ultimately 
delayed implementation of that rule 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. CSAPR's 
Phase 2 budgets were originally promulgated to begin on January 1, 
2014, and are now scheduled to begin on January 1, 2017. As part of the 
remand, the D.C. Circuit found the Ohio 2014 NOX budget was 
invalid, stating that based on EPA's own data, Ohio made no 
contribution to downwind states' nonattainment. On November 16, 2015, 
EPA proposed the CSAPR Update Rule (80 FR 75706) which, when finalized, 
will establish permanent and enforceable reduction through revised 
NOX ozone season budgets for Ohio.
    Because the emission reduction requirements of CAIR were 
enforceable through the 2011 control period, and because CSAPR has been 
promulgated to address the requirements previously addressed by CAIR 
and will achieve similar or greater reductions once finalized, EPA has 
determined that the EGU emission reductions that helped lead to 
attainment in the Cincinnati-Hamilton area can now be considered 
permanent and enforceable and that the requirement of CAA section 
107(d)(3)(E)(iii) has been met.
b. Emission Reductions
    Ohio developed an emissions inventory for NOX, direct 
PM2.5, and SO2 for 2005, one of the years used to 
designate the area as nonattainment, and 2008, one of the years the 
Cincinnati-Hamilton area monitored attainment of the standard.
    Emissions of SO2 and NOX from EGUs were 
derived from EPA's Clean Air Market's acid rain database. These 
emissions reflect Ohio's NOX emission budgets resulting from 
EPA's NOX SIP call. The 2008 emissions from EGUs reflect 
Ohio's emission caps under CAIR. All other point source emissions were 
obtained from Ohio's source facility emissions reporting.
    Area source emissions for the Cincinnati-Hamilton area for 2005 
were taken from periodic emissions inventories.\8\ These 2005 area 
source emission estimates were extrapolated to 2008. Source growth 
factors were supplied by LADCO. These growth factors were based on the 
U.S Department of Commerce Bureau of Economic Analysis (BEA) growth 
factors, with some updated local information.
---------------------------------------------------------------------------

    \8\ Periodic emission inventories are derived by states every 
three years and reported to EPA. These periodic emission inventories 
are required by the Federal Consolidated Emissions Reporting Rule, 
codified at 40 CFR Subpart A. EPA revised these and other emission 
reporting requirements in a final rule published on December 17, 
2008, at 73 FR 76539.
---------------------------------------------------------------------------

    Nonroad mobile source emissions were extrapolated from nonroad 
mobile source emissions reported in EPA's 2005 National Emissions 
Inventory (NEI). Contractors were employed by LADCO to estimate 
emissions for commercial marine vessels and railroads.
    On-road mobile source emissions were calculated using EPA's mobile 
source emission factor model, MOVES2010, in conjunction with 
transportation model results developed by the Ohio-Kentucky-Indiana 
Regional Council of Governments (OKI).
    All emissions estimates discussed below were documented in the 
submittals and appendices to Ohio's redesignation request submittal of 
July 22, 2016. For these data and additional emissions inventory data, 
the reader is referred to EPA's digital docket for this rule, http://www.regulations.gov, for docket number EPA-R05-OAR-2016-0479, which 
includes a digital copy of Ohio's submittal.
    Emissions data in tons per year (tpy) for the Cincinnati-Hamilton 
area are shown in Tables 2, 3, and 4 below.

 Table 2--Comparison of 2005 Emissions From the Nonattainment Year and 2008 Emissions for an Attainment Year for
                                       NOX in the Cincinnati-Hamilton Area
 
----------------------------------------------------------------------------------------------------------------
                                                                                                   Net change
                          Sector                                  2005              2008           (2008-2005)
----------------------------------------------------------------------------------------------------------------
EGU Point.................................................         55,930.44         46,853.89         -9,076.55
Non-EGU...................................................         10,371.70          9,790.50           -581.20
Non-road..................................................         12,417.57         10,561.92         -1,855.65
Other (Area)..............................................          7,810.74          7,975.67            164.93
Marine, Air, and Rail (MAR)...............................          9,352.60          9,052.95           -299.65
On-road...................................................         71,919.89         64,471.22         -7,448.67
                                                           -----------------------------------------------------

[[Page 800]]

 
    Total.................................................        167,802.94        148,706.15        -19,096.79
----------------------------------------------------------------------------------------------------------------


 Table 3--Comparison of 2005 Emissions From the Nonattainment Year and 2008 Emissions for an Attainment Year for
                                       SO2 in the Cincinnati-Hamilton Area
 
----------------------------------------------------------------------------------------------------------------
                                                                                                   Net change
                          Sector                                  2005              2008           (2008-2005)
----------------------------------------------------------------------------------------------------------------
EGU Point.................................................        218,395.56         98,334.17       -120,061.39
Non-EGU...................................................         15,532.09         13,483.92         -2,048.17
Non-road..................................................          1,057.16            416.87           -640.29
Area......................................................          3,494.39          3,520.77             26.38
MAR.......................................................          1,092.58            982.82           -109.76
On-road...................................................            392.00            277.59           -114.41
                                                           -----------------------------------------------------
    Total.................................................        239,963.78        117,016.14       -122,947.64
----------------------------------------------------------------------------------------------------------------


 Table 4--Comparison of 2005 Emissions From the Nonattainment Year and 2008 Emissions for an Attainment Year for
                                  Direct PM2.5 in the Cincinnati-Hamilton Area
 
----------------------------------------------------------------------------------------------------------------
                                                                                                   Net change
                          Sector                                  2005              2008           (2008-2005)
----------------------------------------------------------------------------------------------------------------
EGU Point.................................................          2,062.91          1,633.15           -429.76
Non-EGU...................................................          1,352.79          1,458.52            105.73
Non-road..................................................            984.35            853.89           -130.46
Area......................................................          1,828.85          1,864.80             35.95
MAR.......................................................            416.20            414.43             -1.77
On-road...................................................          2,810.30          2,679.85           -130.45
                                                           -----------------------------------------------------
    Total.................................................          9,455.40          8,904.64           -550.76
----------------------------------------------------------------------------------------------------------------

    Table 2 shows reductions in NOX emissions for the 
Cincinnati-Hamilton area by 19,096.79 tpy between 2005 (nonattainment 
year) and 2008 (attainment year). Table 3 shows that the Cincinnati-
Hamilton area reduced SO2 emissions by 122,947.64 tpy 
between 2005 and 2008. Table 4 shows reductions in direct 
PM2.5 emissions for the Cincinnati-Hamilton area by 550.76 
tpy between 2005 and 2008.
4. Maintenance Plan Pursuant to Section 175A of the CAA (Section 
107(d)(3)(E)(iv))
    EPA has fully approved an applicable maintenance plan that meets 
the requirements of section 175(a) on December 23, 2011. See 76 FR 
80253. In conjunction with Ohio's request to redesignate the 
Cincinnati-Hamilton nonattainment area to attainment, Ohio has 
submitted an updated attainment inventory of the maintenance plan to 
reflect the provisions of subpart 4 (Title I, Part D) of the CAA, and 
EPA is updating the maintenance plan to 2027.
a. What is required in a maintenance plan?
    Section 175A of the CAA sets forth the required elements of a 
maintenance plan for areas seeking redesignation from nonattainment to 
attainment. Under section 175A, the plan must demonstrate continued 
attainment of the applicable NAAQS for at least ten years after EPA 
approves a redesignation to attainment. Eight years after 
redesignation, the state must submit a revised maintenance plan which 
demonstrates that attainment will continue to be maintained for ten 
years following the initial ten year maintenance period. To address the 
possibility of future NAAQS violations, the maintenance plan must 
contain contingency measures with a schedule for implementation as EPA 
deems necessary to assure prompt correction of any future 
PM2.5 violations.
    The Calcagni memorandum provides additional guidance on the content 
of a maintenance plan. The memorandum states that a maintenance plan 
should address the following items: The attainment emissions inventory, 
a maintenance demonstration showing maintenance for the ten years of 
the maintenance period, a commitment to maintain the existing 
monitoring network, factors and procedures to be used for verification 
of continued attainment of the NAAQS, and a contingency plan to prevent 
or correct future violations of the NAAQS.
    Section 175A requires a state seeking redesignation to attainment 
to submit a SIP revision to provide for the maintenance of the NAAQS in 
the area ``for at least 10 years after the redesignation.'' EPA has 
interpreted this as a showing of maintenance ``for a period of ten 
years following redesignation.'' Calcagni memorandum, p. 9. Where the 
emissions inventory method of showing maintenance is used, its purpose 
is to show that emissions during the maintenance period will not 
increase over the

[[Page 801]]

attainment year inventory. Calcagni memorandum, pp. 9-10.
    As discussed in detail in the section below, the state's 
maintenance plan submission expressly documents that the area's 
emissions inventories will remain below the attainment year inventories 
through 2021. In addition, for the reasons set forth below, EPA 
believes that the state's submission, in conjunction with additional 
supporting information, further demonstrates that the area will 
continue to maintain the 1997 annual SO2 NAAQS at least 
through 2027. Thus, any EPA action to finalize its proposed approval of 
the redesignation request and maintenance plans in 2017, will be based 
on a showing, in accordance with section 175A, that the state's 
maintenance plan provides for maintenance for at least ten years after 
redesignation.
b. Attainment Inventory
    Ohio developed an emissions inventory for NOX, direct 
PM2.5, and SO2 for 2008, one of the years in the 
period during which the Cincinnati-Hamilton area monitored attainment 
of the 1997 annual PM2.5 standard, as described previously. 
The attainment level of emissions is summarized in Tables 2, 3, and 4, 
above. Ohio also included emissions inventories for VOCs and ammonia 
from 2007, in accordance with the provisions of Subpart 4 (Title I, 
Part D) of the CAA. These emissions are summarized in Table 6, in 
discussion of the maintenance plan below.
c. Demonstration of Maintenance
    Ohio has a fully approved maintenance plan that meets the 
requirements of Section 175(A). See 76 FR 80253. Along with the 
redesignation request, Ohio submitted an updated attainment inventory 
to reflect the provision of subpart 4. Ohio's plan demonstrates 
maintenance of the 1997 annual PM2.5 standard through 2021 
by showing that current and future emissions of NOX, 
directly emitted PM2.5 and SO2 in the area remain 
at or below attainment year emission levels. Section 175A requires a 
state seeking redesignation to attainment to submit a SIP revision to 
provide for the maintenance of the NAAQS in the area ``for at least 10 
years after the redesignation.'' EPA has interpreted this as a showing 
of maintenance ``for a period of ten years following redesignation.'' 
Calcagni memorandum, p. 9. Where the emissions inventory method of 
showing maintenance is used, its purpose is to show that emissions 
during the maintenance period will not increase over the attainment 
year inventory. Calcagni memorandum, pp. 9-10.
    As discussed in detail in the section below, Ohio's maintenance 
plan expressly documents that the area's emissions inventories will 
remain below the attainment year inventories through 2021. In addition, 
for the reasons set forth below, EPA believes that the state's 
submission, in conjunction with additional supporting information, 
further demonstrates that the area will continue to maintain the 
PM2.5 standard at least through 2027. Thus, if EPA finalizes 
its proposed approval of the redesignation request in 2017, it will be 
based on a showing, in accordance with section 175A, that the state's 
maintenance plan provides for maintenance for at least ten years after 
redesignation.
    Ohio's plan demonstrates maintenance of the 1997 annual 
PM2.5 NAAQS through 2021 by showing that current and future 
emissions of NOX, directly emitted PM2.5 and 
SO2 for the area remain at or below attainment year emission 
levels.
    The rate of decline in emissions of PM2.5, 
NOX, and SO2 from the attainment year 2008 
through 2021 indicates that the emissions inventory levels not only 
significantly decline between 2008 and 2021, but also will continue to 
decline through 2027 and beyond. PM2.5 emissions in the 
nonattainment area are projected to decrease by 270.09 tpy in 2015 and 
702.01 tpy in 2021. NOX emissions in the nonattainment area 
are projected to decrease by 42,994.13 tpy in 2015 and 69,887.02 tpy in 
2021. SO2 emissions in the nonattainment area are projected 
to decline by 4,765.88 tpy in 2015 and 28,505.87 in 2021. These rates 
of decline are consistent with monitored and projected air quality 
trends; and emissions reductions achieved through emissions controls 
and regulations that will remain in place beyond 2027, and through 
fleet turnover that will continue beyond 2027, among other factors. EPA 
is proposing that the previously approved MVEBs are adequate for 
conformity purposes. See section 5 below for further details regarding 
MVEBs.
    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 uses emissions inventory 
projections for the years 2018 and 2021 to demonstrate maintenance for 
the entire Cincinnati-Hamilton area. The projected emissions were 
estimated by Ohio, with assistance from LADCO and OKI, who used the 
MOVES2010 model for mobile source projections. Projection modeling of 
inventory emissions was done for the 2018 interim year emissions using 
estimates based on the 2009 and 2018 LADCO modeling inventory, using 
LADCO's growth factors, for all sectors. The 2021 maintenance year 
emission estimates were based on emissions estimates from the 2018 
LADCO modeling. Table 5 shows the 2008 attainment base year emission 
estimates and the 2015 and 2021 emission projections for the 
Cincinnati-Hamilton area, taken from Ohio's July 22, 2016, submission.

 Table 5--Comparison of 2008, 2015 and 2021 NOX, Direct PM2.5, and SO2 Emission Totals (tpy) for the Cincinnati-
                                                  Hamilton Area
----------------------------------------------------------------------------------------------------------------
                                              SO2                        NOX                      PM2.5
----------------------------------------------------------------------------------------------------------------
2008 (baseline)..................  117,016.14...............  148,706.15..............  8,904.64.
2015 (interim)...................  112,250.26...............  105,712.02..............  8,634.55.
2021 (maintenance)...............  88,510.27................  78,819.13...............  8,202.63.
Projected Decrease (2021-2008)...  28,505.87................  69,887.02...............  702.01.
                                   24% decrease.............  47% decrease............  8% decrease.
----------------------------------------------------------------------------------------------------------------

    Table 5 shows that, for the period between 2008 and the maintenance 
projection for 2021, the Cincinnati-Hamilton area will reduce 
NOX emissions by 69,887.02 tpy; direct PM2.5 
emissions by 702.01 tpy; and SO2 emissions by 28,505.87 tpy. 
The 2021 projected emissions levels are significantly below attainment 
year inventory levels, and, based on the rate of decline, it is highly 
improbable that any increases in these levels will occur

[[Page 802]]

in 2027 and beyond. Thus, the emissions inventories set forth in Table 
5 show that the area will continue to maintain the 1997 annual 
PM2.5 standard during the maintenance period and at least 
through 2027.
    As Table 1 demonstrates, monitored PM2.5 design value 
concentrations in the Cincinnati-Hamilton area are well below the NAAQS 
in the years beyond 2008, the attainment year for the area. Further, 
those values are trending downward as time progresses. Based on the 
future projections of emissions in 2015 and 2021 showing significant 
emissions reductions in direct PM2.5, NOX, and 
SO2, it is very unlikely that monitored PM2.5 
values in 2027 and beyond will show violations of the NAAQS. 
Additionally, the 2013-2015 design values, which range from 9.5 to 11.2 
[mu]g/m\3\, provide a sufficient margin in the unlikely event emissions 
rise slightly in the future.
Maintenance Plan Evaluation of Ammonia and VOCs
    With regard to the redesignation of the Cincinnati-Hamilton area, 
in evaluating the effect of the Court's remand of EPA's implementation 
rule, which included presumptions against consideration of VOCs and 
ammonia as PM2.5 precursors, EPA in this proposal is also 
considering the impact of the decision on the maintenance plan required 
under sections 175A and 107(d)(3)(E)(iv). To begin with, EPA notes that 
the area has attained the 1997 annual PM2.5 standard and 
that the state has shown that attainment of the standard is due to 
permanent and enforceable emission reductions.
    EPA proposes to confirm that the state's maintenance plan shows 
continued maintenance of the standard by tracking the levels of the 
precursors whose control brought about attainment of the 1997 
PM2.5 standard in the Cincinnati-Hamilton area. EPA 
therefore believes that the only additional consideration related to 
the maintenance plan requirements that results from the Court's January 
4, 2013 decision is that of assessing the potential role of VOCs and 
ammonia in demonstrating continued maintenance in this area. As 
explained below, based upon documentation provided by the state and 
supporting information, EPA believes that the maintenance plan for the 
Cincinnati-Hamilton area need not include any additional emission 
reductions of VOCs or ammonia in order to provide for continued 
maintenance of the standard.
    First, as noted above in EPA's discussion of section 189(e), VOCs 
emission levels in this area have historically been well-controlled 
under SIP requirements related to ozone and other pollutants. Second, 
total ammonia emissions throughout the Cincinnati-Hamilton area are 
very low, estimated to be less than 3,200 tpy. See Table 6 below. This 
amount of ammonia emissions appears especially small in comparison to 
the total amounts of SO2, NOX, and even direct 
PM2.5 emissions from sources in the area. Third, as 
described below, available information shows that no precursor, 
including VOCs and ammonia, is expected to increase over the 
maintenance period so as to interfere with or undermine the state's 
maintenance demonstration.
    Ohio's maintenance plan shows that emissions of direct 
PM2.5, SO2, and NOX are projected to 
decrease by 702.01 tpy, 28,505.87 tpy, and 69,887.022 tpy, 
respectively, over the maintenance period. See Table 5 above. In 
addition, emissions inventories used in the regulatory impact analysis 
(RIA) for the 2012 PM2.5 NAAQS show that VOCs and ammonia 
emissions are projected to decrease by 16,716 tpy and 119 tpy, 
respectively between 2007 and 2020. See Table 6 below. While the RIA 
emissions inventories are only projected out to 2020, there is no 
reason to believe that this downward trend would not continue through 
2027. Given that the Cincinnati-Hamilton area is already attaining the 
1997 annual PM2.5 NAAQS even with the current level of 
emissions from sources in the area, the downward trend of emissions 
inventories would be consistent with continued attainment. Indeed, 
projected emissions reductions for the precursors that the state is 
addressing for purposes of the 1997 PM2.5 NAAQS indicate 
that the area should continue to attain the NAAQS following the 
precursor control strategy that the state has already elected to 
pursue. Even if VOCs and ammonia emissions were to increase 
unexpectedly between 2020 and 2027, the overall emissions reductions 
projected in direct PM2.5, SO2, and 
NOX would be sufficient to offset any increases. For these 
reasons, EPA believes that local emissions of all of the potential 
PM2.5 precursors will not increase to the extent that they 
will cause monitored PM2.5 levels to violate the 1997 
PM2.5 standard during the maintenance period.

            Table 6--Comparison of 2007 and 2020 VOC and Ammonia Emission Totals by Source Sector (tpy) for the Cincinnati-Hamilton Area \9\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                VOC                                           Ammonia
                                                         -----------------------------------------------------------------------------------------------
                         Sector                                                             Net change                                      Net change
                                                               2007            2020          2020-2007         2007            2020          2020-2007
--------------------------------------------------------------------------------------------------------------------------------------------------------
fires...................................................             224             224               0              16              16               0
nonpoint................................................          24,149          24,080             -69           2,158           2,223              65
nonroad.................................................           9,294           5,228          -4,066              13              15               2
onroad..................................................          20,317           8,041         -12,275             890             481            -409
point...................................................           5,138           4,831            -306             109             332             222
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................          59,121          42,404         -16,716           3,186           3,067            -119
--------------------------------------------------------------------------------------------------------------------------------------------------------

    In addition, available air quality modeling analyses show continued 
maintenance of the standard during the maintenance period. The current 
annual design values for the area range from 9.5 to 11.2 [mu]g/m3 
(based on 2013-2015 air quality data), which are well below the 1997 
annual PM2.5 NAAQS of 15 [mu]g/m\3\. Moreover, the modeling 
analysis conducted for the RIA for the 2012 PM2.5 NAAQS 
indicates that the design values for this area are expected to continue 
to decline through 2020. In the RIA analysis, the highest 2020 modeled 
design value for the Cincinnati-Hamilton area is 10.5 [mu]g/m\3\. Given 
that precursor emissions are projected to decrease through 2027, it is 
reasonable to conclude that monitored PM2.5 levels

[[Page 803]]

in this area will also continue to decrease through 2027.
---------------------------------------------------------------------------

    \9\ These emissions estimates were taken from the emissions 
inventories developed for the RIA for the 2012 PM2.5 
NAAQS which can be found in the docket.
---------------------------------------------------------------------------

    Thus, EPA believes that there is ample justification to conclude 
that the Cincinnati-Hamilton area should be redesignated, even taking 
into consideration the emissions of other precursors potentially 
relevant to PM2.5. After consideration of the D.C. Circuit's 
January 4, 2013 decision, and for the reasons set forth in this notice, 
EPA proposes to approve the state's revised attainment inventory into 
the previously approved maintenance plan.
    Based on the information summarized above, Ohio has adequately 
demonstrated maintenance of the 1997 PM2.5 standard in this 
area for a period extending in excess of ten years from expected final 
action on Ohio's redesignation request. EPA finds that currently 
approved plan will provide for maintenance.
d. Monitoring Network
    Ohio's approved maintenance plan includes additional elements. 
Ohio's plan includes a commitment to continue to operate its EPA-
approved monitoring network, as necessary to demonstrate ongoing 
compliance with the NAAQS. As detailed above, there are nine monitors 
measuring PM2.5 concentrations in the Cincinnati-Hamilton 
area, and eight of the nine are operated by Ohio. The one other monitor 
is located in Kentucky.
e. Verification of Continued Attainment
    Ohio remains obligated to continue to quality-assure monitoring 
data and enter all data into the AQS in accordance with Federal 
guidelines. Ohio will use these data, supplemented with additional 
information as necessary, to assure that the area continues to attain 
the standard. Ohio will also continue to develop and submit periodic 
emission inventories as required by the Federal Consolidated Emissions 
Reporting Rule (67 FR 39602, June 10, 2002) to track future levels of 
emissions. Both of these actions will help to verify continued 
attainment in accordance with 40 CFR part 58.
f. Contingency Plan
    The contingency plan provisions are designed to promptly correct or 
prevent a violation of the NAAQS that might occur after redesignation 
of an area to attainment. Section 175A of the CAA requires that a 
maintenance plan include such contingency measures as EPA deems 
necessary to assure that the state will promptly correct a violation of 
the NAAQS that occurs after redesignation. The maintenance plan should 
identify the contingency measures to be adopted, a schedule and 
procedure for adoption and implementation of the contingency measures, 
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 adopted and implemented. The 
maintenance plan must include a requirement that the state will 
implement all pollution control measures that were contained in the SIP 
before redesignation of the area to attainment. See section 175A(d) of 
the CAA. As described above in section III.4, Ohio's previously 
approved maintenance plan includes all necessary contingency measures 
required under section 175A(d). See 76 FR 80253.
    Ohio further commits to conduct ongoing review of its data, and if 
monitored concentrations or emissions are trending upward, Ohio commits 
to take appropriate steps to avoid a violation if possible. Ohio 
commits to continue implementing SIP requirements upon and after 
redesignation.
    EPA believes that Ohio's approved contingency measures, as well as 
the commitment to continue implementing any SIP requirements, satisfy 
the pertinent requirements of section 175A(d).
    As required by section 175A(b) of the CAA, Ohio commits to submit 
to EPA an updated PM2.5 maintenance plan eight years after 
redesignation of the Cincinnati-Hamilton area to cover an additional 
ten year period beyond the initial ten year maintenance period. As 
required by section 175A of the CAA, Ohio has also committed to retain 
the PM2.5 control measures contained in the SIP prior to 
redesignation.
    For all of the reasons set forth above, EPA determines that the 
approved maintenance plan is still applicable and meets all the 
contingency plan requirements of CAA section 175A.

5. Motor Vehicle Emissions Budget (MVEBs) for the Mobile Source 
Contribution to PM2.5 and NOX

a. How are MVEBs developed and what are the MVEBs for the Cincinnati-
Hamilton area?
    Under the CAA, states are required to submit, at various times, 
control strategy SIP revisions and maintenance plans for 
PM2.5 nonattainment areas and for areas seeking 
redesignation to attainment of the PM2.5 standard. These 
emission control strategy SIP revisions (e.g., RFP and attainment 
demonstration SIP revisions) and maintenance plans create MVEBs based 
on on-road mobile source emissions for criteria pollutants and/or their 
precursors to address pollution from on-road transportation sources. 
The MVEBs are the portions 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, 
RFP, or maintenance, as applicable.
    Under 40 CFR part 93, a MVEB for an area seeking a redesignation to 
attainment is established for the last year of the maintenance plan and 
could also be established for an interim year or years. 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).
    Under section 176(c) of the CAA, new transportation plans and 
transportation improvement programs (TIPs) must be evaluated to 
determine if they conform to the purpose of the area's SIP. Conformity 
to the SIP means that transportation activities will not cause new air 
quality violations, worsen existing air quality violations, or delay 
timely attainment of the NAAQS or any required interim milestone. If a 
transportation plan or TIP does not conform, most new transportation 
projects that would expand the capacity of roadways cannot go forward. 
Regulations at 40 CFR part 93 set forth EPA policy, criteria, and 
procedures for demonstrating and assuring conformity of such 
transportation activities to a SIP.
    When reviewing SIP revisions containing MVEBs, including attainment 
strategies, rate-of-progress plans, and maintenance plans, EPA must 
affirmatively find adequate and/or approve the MVEBs for use in 
determining transportation conformity before the MVEBs can be used. 
Once EPA affirmatively approves and/or finds the submitted MVEBs to be 
adequate for transportation conformity purposes, the MVEBs must be used 
by state and Federal agencies in determining whether proposed 
transportation plans and TIPs conform to the SIP as required by section 
176(c) of the CAA. EPA's substantive criteria for determining the 
adequacy of MVEBs are set out in 40 CFR 93.118(e)(4). Additionally, to 
approve a MVEB, EPA must complete a thorough review of the SIP and 
conclude that the SIP will achieve its overall purpose. In this case, 
EPA must review Ohio's PM2.5 maintenance plan and conclude 
that it will provide for maintenance of the 1997 annual 
PM2.5 standard in the Cincinnati-Hamilton area.

[[Page 804]]

    The maintenance plans previously submitted by Ohio for the area 
contained PM2.5 and NOX MVEBs for the area for 
the year 2021. Ohio calculated the MVEBs using MOVES2010. These 
approved budgets are used in future conformity determinations and 
regional emissions analyses prepared by the OKI, and will have to be 
based on the use of MOVES2010 or the most recent version of MOVES 
required to be used in transportation conformity determinations.\10\ 
The state has determined the 2021 MVEBs for the combined Ohio and 
Indiana portions of the Cincinnati-Hamilton area to be 1,241.19 tpy for 
primary PM2.5 and 21,747.71 tpy for NOX. The Ohio 
and Indiana portion of the area included ``safety margins'' as provided 
for in 40 CFR 93.124(a) (described below) of 112.84 tpy for primary 
PM2.5 and 2,836.65 tpy for NOX in the 2021 MVEBs, 
respectively, to provide for on-road mobile source growth. Ohio did not 
provide emission budgets for SO2, VOCs, and ammonia because 
it concluded, consistent with EPA's presumptions regarding these 
precursors, that emissions of these precursors from on-road motor 
vehicles are not significant contributors to the area's 
PM2.5 air quality problem.
---------------------------------------------------------------------------

    \10\ EPA described the circumstances under which an area would 
be required to use MOVES in transportation conformity determinations 
in its March 2, 2010, Federal Register notice officially releasing 
MOVES2010 for use in SIPs and transportation conformity 
determinations. (75 FR 9413)
---------------------------------------------------------------------------

    In the Cincinnati-Hamilton area, the motor vehicle budgets 
including the safety margins and motor vehicle emission projections for 
both NOX and PM2.5 are equal to the levels in the 
attainment year.
    EPA has reviewed the previously approved budgets for 2021 including 
the added safety margins using the conformity rule's adequacy criteria 
found at 40 CFR 93.118(e)(4) and the conformity rule's requirements for 
safety margins found at 40 CFR 93.124(a). EPA has reviewed the approved 
budgets and the maintenance plan, and EPA is determining that the 2021 
direct PM2.5 and NOX budgets, including the 
requested safety margins for the Cincinnati-Hamilton area, are adequate 
for use in conformity.
b. What action is EPA taking on the submitted motor vehicle emissions 
budgets?
    EPA previously approved Ohio's MVEBs for use to determine 
transportation conformity in the Cincinnati-Hamilton area and these 
budgets remain applicable. EPA has determined that the area can 
maintain attainment of the 1997 annual PM2.5 NAAQS for the 
relevant maintenance period and no changes to the plan have been made. 
See 76 FR 80253.

6. Comprehensive Emissions Inventory

    As discussed above, section 172(c)(3) of the CAA requires areas to 
submit a comprehensive emissions inventory including direct PM and all 
four precursors (SO2, NOX, VOCs, and ammonia). 
EPA approved the Ohio 2005 base year emissions inventory on December 
23, 2011 (76 FR 80253). This previously approved base year emissions 
inventory detailed emissions of PM2.5, SO2, and 
NOX for 2005. Emissions inventories for VOCs and ammonia 
from 2007, taken from the RIA for the 2012 PM2.5 NAAQS, have 
been added as part of this submittal in accordance with the provisions 
of subpart 4 (Title I, Part D) of the CAA. Emissions contained in the 
submittal cover the general source categories of point sources, area 
sources, on-road mobile sources, and nonroad mobile sources.
    Based upon EPA's previous action and 2007 emissions inventory for 
VOCs and ammonia, the emissions inventory was complete and accurate, 
and met the requirement of CAA section 172(c)(3).
IV. EPA's Proposed Actions
    EPA is proposing to take several actions related to redesignation 
of the Cincinnati-Hamilton area to attainment for the 1997 annual 
PM2.5 NAAQS.
    EPA has previously approved Ohio's PM2.5 maintenance 
plan and MVEBs for the Cincinnati-Hamilton area. EPA is proposing to 
determine that this plan and budgets are still applicable.
    EPA has previously approved the 2005 primary PM2.5, 
NOX, and SO2 base year emissions inventory. EPA 
is proposing to approve Ohio's updated emissions inventory which 
includes emissions inventories for VOCs and ammonia from 2007. EPA is 
proposing that Ohio meets the emissions inventory requirement under 
section 107(d)(3)(E)(iii).
    EPA is proposing to approve the RACM/RACT portion of Ohio's prior 
Cincinnati-Hamilton area attainment plan SIP revision as providing 
adequate RACM/RACT consistent with the provisions of 40 CFR 51.1010(b), 
because Ohio has demonstrated with a RACM/RACT analysis that no further 
control measures would advance the attainment date in the area.
    EPA is proposing that Ohio meets the requirements for redesignation 
of the Cincinnati-Hamilton area to attainment of the 1997 annual 
PM2.5 NAAQS under section 107(d)(3)(E) of the CAA. EPA is 
thus proposing to grant Ohio's request to change the designation of its 
portion of the Cincinnati-Hamilton area from nonattainment to 
attainment for the 1997 annual PM2.5 NAAQS.
    If finalized, approval of the redesignation request would change 
the official designation of the Ohio portion of the Cincinnati-Hamilton 
area for the 1997 annual PM2.5 NAAQS, found at 40 CFR part 
81, from nonattainment to attainment. If finalized, EPA would determine 
that the previously approved maintenance plan is still applicable to 
the Cincinnati-Hamilton area for the 1997 annual PM2.5 
NAAQS.

V. 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 proposes to approve state law as 
meeting Federal requirements and, if finalized, will not impose 
additional requirements beyond those imposed by state law. For that 
reason, this actions:
     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);

[[Page 805]]

     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not 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 Clean Air Act; 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

40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Intergovernmental relations, Particulate matter.

40 CFR Part 81

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

    Dated: December 13, 2016.
Robert Kaplan,
Acting Regional Administrator, Region 5.
[FR Doc. 2016-31635 Filed 1-3-17; 8:45 am]
BILLING CODE 6560-50-P