[Federal Register Volume 86, Number 97 (Friday, May 21, 2021)]
[Rules and Regulations]
[Pages 27524-27532]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-10510]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R09-OAR-2019-0440; FRL-10022-39-Region 9]


Clean Air Plans; 2008 8-Hour Ozone Nonattainment Area 
Requirements; Western Nevada County, California

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Environmental Protection Agency (EPA) is taking final 
action to approve, or conditionally approve, all or portions of a state 
implementation plan (SIP) revision submitted by the State of California 
to meet Clean Air Act (CAA or ``Act'') requirements for the 2008 8-hour 
ozone national ambient air quality standards (NAAQS or ``standards'') 
in the Nevada County (Western part), California ozone nonattainment 
area (``Western Nevada County''). The SIP revision is the ``Ozone 
Attainment Plan, Western Nevada County, State Implementation Plan for 
the 2008 Primary Federal 8-Hour Ozone Standard of .075 ppm'' (``2018 
Western Nevada County Ozone Plan'' or ``Plan''). The 2018 Western 
Nevada County Ozone Plan addresses the ``Serious'' nonattainment area 
requirements for the 2008 ozone NAAQS, including the requirements for 
emissions inventories, attainment demonstration, reasonable further 
progress, reasonably available control measures, and contingency 
measures, among others; and establishes motor vehicle emissions 
budgets. The EPA is approving the 2018 Western Nevada County Ozone Plan 
as meeting all the applicable ozone nonattainment area requirements 
except for the contingency measure requirement, which the EPA is 
conditionally approving.

DATES: This rule is effective on June 21, 2021.

ADDRESSES: The EPA has established a docket for this action under 
Docket ID No. EPA-R09-OAR-2019-0440. All documents in the docket are 
listed on the https://www.regulations.gov website. Although listed in 
the index, some information is not publicly available, e.g., 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Certain other material, such as 
copyrighted material, is not placed on the internet and will be 
publicly available only in hard copy form. Publicly available docket 
materials are available through https://www.regulations.gov, or please 
contact the person identified in the FOR FURTHER INFORMATION CONTACT 
section for additional availability information. If you need assistance 
in a language other than English or if you are a person with 
disabilities who needs a reasonable accommodation at no cost to you, 
please contact the person identified in the FOR FURTHER INFORMATION 
CONTACT section.

FOR FURTHER INFORMATION CONTACT: T. Khoi Nguyen, Air Planning Office 
(AIR-2), EPA Region IX, 75 Hawthorne Street, San Francisco, CA 94105, 
(415) 947-4120, or by email at [email protected].

SUPPLEMENTARY INFORMATION: 

Table of Contents

I. Summary of the Proposed Action
II. Public Comments and EPA Responses
III. Final Action
IV. Statutory and Executive Order Reviews

I. Summary of the Proposed Action

    On January 12, 2021, the EPA proposed to approve, under CAA section 
110(k)(3), and to conditionally approve, under CAA section 110(k)(4), a 
submittal from the California Air Resources Board (CARB) and the 
Northern Sierra Air Quality Management District (NSAQMD or 
``District'') as a revision to the California SIP for the Western 
Nevada County nonattainment area.\1\ The SIP revision is the 2018 
Western Nevada County Ozone Plan.\2\ We refer to our January 12, 2021, 
proposed rule as the ``proposed rule.''
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    \1\ 86 FR 2318 (January 12, 2021). The Western Nevada County 
nonattainment area for the 2008 ozone NAAQS consists of the portion 
of Nevada County west of the ridge of the Sierra Nevada mountains. 
For a precise definition of the boundaries of the Western Nevada 
County 2008 ozone nonattainment area, see 40 CFR 81.305.
    \2\ Letter dated December 2, 2018, from Richard Corey, Executive 
Officer, CARB, to Mike Stoker, Regional Administrator, U.S. 
Environmental Protection Agency Region IX. The 2018 Western Nevada 
County Ozone Plan was submitted electronically through the EPA's 
State Planning Electronic Collaboration System on December 7, 2018, 
making this date the effective date of submittal. The Plan was 
deemed complete by operation of law six months after submittal, on 
June 7, 2019. Our proposed rule incorrectly identified the December 
2, 2018 letter date as the submittal date, and June 2, 2019 as the 
date that the Plan was deemed complete by operation of law.
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    In our proposed rule, we provided background information on the 
ozone standards,\3\ area designations, and related SIP revision 
requirements under the CAA and the EPA's implementing regulations for 
the 2008 ozone standards, referred to as the 2008 Ozone SIP 
Requirements Rule (``2008 Ozone SRR'').\4\ To summarize, the Western 
Nevada County ozone nonattainment area is classified as Serious for the 
2008 ozone NAAQS, and the 2018 Western Nevada County Ozone Plan was 
developed to address the statutory and regulatory requirements for 
revisions to the SIP for the Western Nevada County Serious ozone 
nonattainment area.
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    \3\ The 1-hour ozone NAAQS is 0.12 parts per million (ppm) (one-
hour average), the 1997 ozone NAAQS is 0.08 ppm (eight-hour 
average), and the 2008 ozone NAAQS is 0.075 ppm (eight-hour 
average).
    \4\ 2008 Ozone SRR, 80 FR 12264, 12283 (March 6, 2015).
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    Our proposed conditional approval of the contingency measures 
element of the 2018 Western Nevada County Ozone Plan relied on specific 
commitments: (1) From the District to adopt a rule that

[[Page 27525]]

would provide for additional emissions reductions in the event that 
Western Nevada County fails to meet a reasonable further progress (RFP) 
milestone or fails to attain the 2008 ozone NAAQS by the applicable 
attainment date, and (2) from CARB to submit the adopted District rule 
to the EPA as a SIP revision within 12 months of our final action.\5\ 
For more information on the SIP revision submittals and related 
commitments, please see our proposed rule.
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    \5\ Letter dated November 16, 2020, from Richard Corey, 
Executive Officer, CARB, to John Busterud, Regional Administrator, 
EPA Region IX. CARB's letter also forwarded the District's 
commitment letter to the EPA. The District's letter is dated October 
26, 2020, from Gretchen Bennitt, NSAQMD Air Pollution Control 
Officer, to Richard Corey, CARB Executive Officer.
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    In our proposed rule, we reviewed the various SIP elements 
contained in the 2018 Western Nevada County Ozone Plan, evaluated them 
for compliance with statutory and regulatory requirements, and 
concluded that they meet all applicable requirements, except for the 
contingency measure requirement, for which the EPA proposed conditional 
approval. More specifically, in our proposed rule, we based our 
proposed actions on the following determinations:
     CARB and the District met all applicable procedural 
requirements for public notice and hearing prior to the adoption and 
submittal of the 2018 Western Nevada County Ozone Plan; \6\
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    \6\ 86 FR 2318, 2321.
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     The 2011 base year emissions inventory from the 2018 
Western Nevada County Ozone Plan is comprehensive, accurate, and 
current, and therefore meets the requirements of CAA sections 172(c)(3) 
and 182(a)(1) and 40 CFR 51.1115. Additionally, the future year 
baseline projections reflect appropriate calculation methods and the 
latest planning assumptions and are properly supported by the SIP-
approved stationary and mobile source measures; \7\
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    \7\ Id. at 2321-2322 and 2326-2330.
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     The process followed by the District to identify 
reasonably available control measures (RACM) is generally consistent 
with the EPA's recommendations; the District's rules provide for the 
implementation of RACM for stationary and area sources of oxides of 
nitrogen (NOX) and volatile organic compounds (VOC); \8\ 
CARB and the Nevada County Transportation Commission (NCTC) provide for 
the implementation of RACM for mobile sources of NOX and 
VOC; there are no additional RACM that would advance attainment of the 
2008 ozone NAAQS in Western Nevada County by at least one year; and 
therefore, the 2018 Western Nevada County Ozone Plan provides for the 
implementation of all RACM as required by CAA section 172(c)(1) and 40 
CFR 51.1112(c); \9\
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    \8\ Ground-level ozone pollution is formed from the reaction of 
VOC and NOX in the presence of sunlight. CARB refers to 
reactive organic gases (ROG) in some of its ozone-related 
submittals. The CAA and the EPA's regulations refer to VOC, rather 
than ROG, but both terms cover essentially the same set of gases. In 
this final rule, we use the term VOC to refer to this set of gases.
    \9\ 86 FR 2318, 2323-2326.
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     The photochemical modeling in the 2018 Western Nevada 
County Ozone Plan shows that existing CARB and District control 
measures are sufficient to attain the 2008 ozone NAAQS by the 
applicable attainment date in Western Nevada County; given the 
documentation in the 2018 Western Nevada County Ozone Plan of modeling 
procedures and good model performance, the modeling is adequate to 
support the attainment demonstration; and therefore the 2018 Western 
Nevada County Ozone Plan meets the attainment demonstration 
requirements of CAA section 182(c)(2)(A) and 40 CFR 51.1108; \10\
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    \10\ Id. at 2326-2328.
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     The 15 percent rate-of-progress (ROP) demonstration 
element in the 2018 Western Nevada County Ozone Plan meets the 
requirements of CAA section 182(b)(1); \11\
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    \11\ Id. at 2330.
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     The RFP demonstration in the 2018 Western Nevada County 
Ozone Plan provides for emissions reductions of VOC or NOX 
of at least 3 percent per year on average for each three-year period, 
beginning 6 years after the baseline year until the attainment date, 
and thereby meets the requirements of CAA sections 172(c)(2) and 
182(c)(2)(B) and 40 CFR 51.1110(a)(2)(ii); \12\
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    \12\ Id. at 2330-2332.
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     The motor vehicle emissions budgets in the 2018 Western 
Nevada County Ozone Plan are consistent with the RFP demonstration, are 
clearly identified and precisely quantified, and meet all other 
applicable statutory and regulatory requirements in 40 CFR 93.118(e), 
including the adequacy criteria in 40 CFR 93.118(e)(4) and (5); \13\ 
and
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    \13\ Id. at 2334-2335.
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     Through previous EPA approvals of the 1993 Photochemical 
Assessment Monitoring Station SIP revision, the ``Annual Network Plan 
Covering Monitoring Operations in 25 California Air Districts, July 
2020'' with respect to the Western Nevada County element,\14\ and 
CARB's enhanced monitoring plan submittal for Western Nevada 
County,\15\ the enhanced monitoring requirements under CAA section 
182(c)(1) and 40 CFR 51.1102 for Western Nevada County have been 
met.\16\
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    \14\ Letter dated November 5, 2020, from Gwen Yoshimura, 
Manager, Air Quality Analysis Office, EPA Region IX, to Ravi 
Ramalingam, Chief, Consumer Products and Air Quality Assessment 
Branch, Air Quality Planning and Science Division, CARB.
    \15\ Letter dated November 9, 2020, from Dr. Michael T. 
Benjamin, Chief, Air Quality Planning and Science Division, CARB, to 
Meredith Kurpius, Assistant Director, EPA Region IX, enclosing the 
``2020 Monitoring Network Assessment (October 2020).'' The 
assessment includes a five-year network assessment and an updated 
enhanced monitoring plan, as required by 40 CFR 58, Appendix D, 
Section 5(a).
    \16\ 86 FR 2318, 2336.
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    In light of the decision from the Ninth Circuit Court of Appeals in 
Bahr v. EPA (``Bahr''),\17\ the District \18\ and CARB \19\ committed 
to supplement the contingency measure element through submission, as a 
SIP revision (within one year of our final conditional approval 
action), of a revised District rule or rules that would add new limits 
or other requirements if an RFP milestone is not met or if the area 
fails to attain the 2008 ozone NAAQS by the applicable attainment 
date.\20\ The EPA proposed to conditionally approve the contingency 
measure element as meeting the requirements of CAA sections 172(c)(9) 
and 182(c)(9).
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    \17\ Bahr v. EPA, 836 F.3d 1218 (9th Cir. 2016) (rejecting 
early-implementation of contingency measures and concluding that the 
contingency measure requirement of CAA section 172(c)(9) can only be 
satisfied by a measure that takes effect at the time the area fails 
to make RFP or attain by the applicable attainment date, not 
before).
    \18\ Letter dated October 26, 2020, from Gretchen Bennitt, 
NSAQMD Air Pollution Control Officer, to Richard Corey, CARB 
Executive Officer.
    \19\ Letter dated November 16, 2020, from Richard Corey, 
Executive Officer, CARB, to John Busterud, Regional Administrator, 
EPA Region IX. CARB's letter also forwarded the District's 
commitment letter to the EPA.
    \20\ 86 FR 2318, 2332-2333.
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    For the emissions statement element, the proposed rule states that 
District Rule 513, ``Emissions Statements and Recordkeeping,'' approved 
as a revision to the California SIP on June 21, 2017,\21\ fulfills the 
relevant emissions statement requirements of CAA section 
182(a)(3)(B)(i).\22\ Accordingly, the emissions statement element was 
previously satisfied through the EPA's approval of Rule 513 on June 21, 
2017. However, the EPA's December 11, 2017 finding of failure to submit 
action incorrectly identified the emissions statement element for 
Western Nevada County as not having been submitted.\23\ Additionally, 
we note that language in

[[Page 27526]]

the proposed rule stating that the EPA was ``propos[ing] to find'' that 
Rule 513 meets the emissions statement requirements could be read to 
indicate that the EPA was proposing to address this element in the 
proposed rule. Therefore, we now clarify that the EPA's June 21, 2017 
approval of Rule 513 satisfied the emissions statement element for 
Western Nevada County prior to the finding of failure to submit action 
and prior to the proposed rule.\24\
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    \21\ 82 FR 28240 (June 21, 2017).
    \22\ 86 FR 2318, 2323.
    \23\ 82 FR 58118 (December 11, 2017).
    \24\ 82 FR 28240, 28241 (finding that Rule 513 fulfills relevant 
emission statement requirements of CAA 182(a)(3)(B)(i)).
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    For the clean fuels fleet program element, the proposed rule states 
that through the 1994 ``Opt-Out Program'' SIP revision, the clean fuels 
fleet program requirements in CAA sections 182(c)(4) and 246 and 40 CFR 
51.1102 for Western Nevada County have been met with respect to the 
2008 ozone NAAQS.\25\ However, CAA section 246(a)(3) applies only to 
certain ozone nonattainment areas with a 1980 population of 250,000 or 
more. As indicated in our proposed rule, Western Nevada County has a 
population of 83,000,\26\ and the area's population was below 250,000 
in 1980.\27\ Therefore, we now clarify that Western Nevada County is 
not subject to the clean fuels fleet program element for the 2008 ozone 
NAAQS.
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    \25\ See 86 FR 2318, 2335.
    \26\ See id. at 2320.
    \27\ See Demographic Information About the County, County of 
Nevada, California, available at https://www.mynevadacounty.com/378/Demographic-Information-About-the-County.
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    Please see our proposed rule for more information concerning the 
background for this action and for a more detailed discussion of the 
rationale for approval or conditional approval of the above-listed 
elements of the 2018 Western Nevada County Ozone Plan.

II. Public Comments and EPA Responses

    The public comment period on the proposed rule opened on January 
12, 2021, the date of its publication in the Federal Register, and 
closed on February 11, 2021. During this period, the EPA received one 
comment letter submitted by Air Law for All, Ltd. on behalf of the 
Center for Biological Diversity and the Center for Environmental Health 
(collectively referred to herein as ``CBD''). We address CBD's comments 
in the following paragraphs of this final rule.
    Comment #1: CBD asserts that the EPA has conflated the requirements 
for contingency measures under subparts 1 and 2 of part D of title I of 
the CAA. CBD distinguishes the generally applicable subpart 1 RFP 
requirements for attainment plans under section 172(c)(2) (the 
commenter refers to these as ``attainment RFP'' requirements) from the 
subpart 2 RFP requirements applicable to ``Moderate'' and above and 
also Serious and above ozone nonattainment areas under CAA 
182(b)(1)(A)(i) and 182(c)(2)(B) respectively (the commenter refers to 
these as ``VOC RFP'' requirements). Similarly, CBD distinguishes the 
subpart 1 contingency measure requirements at CAA 172(c)(9) (which, 
according to the commenter, are applicable upon a failure to make 
``attainment RFP'' or to attain a NAAQS by the applicable attainment 
date) from the subpart 2 contingency measure requirements at CAA 
182(c)(9) (which, according to the commenter, are applicable upon a 
failure to meet any applicable ``VOC RFP'' milestone). CBD argues that 
under CAA 182(c)(9), the subpart 2 VOC RFP contingency measure 
requirements are ``in addition to'' the subpart 1 attainment RFP 
contingency measures, and that this language compels the EPA to require 
separate, distinct VOC RFP contingency measures, including not only the 
triggers for these measures, but the substantive contingency measures 
themselves. CBD asserts that the subpart 1 RFP and contingency measure 
requirements are distinct in purpose from the subpart 2 RFP and 
contingency measure requirements, and that CAA 172(c)(9) attainment RFP 
contingency measures are intended to make progress towards attainment 
while a state assesses the additional reductions needed to timely 
attain the ozone standards, whereas CAA 182(c)(9) VOC RFP contingency 
measures are intended to make progress in VOC emission reductions if 
the state elects to trigger them instead of reclassification or 
adoption of an economic incentive program.
    Additionally, CBD asserts that the EPA entirely fails to discuss 
CAA 182(c)(9)'s clear language, the structural distinction between what 
the commenter asserts are separate attainment RFP and VOC RFP 
requirements, and the corresponding need to have distinct attainment 
RFP contingency measures and VOC RFP contingency measures. Given this 
distinction, CBD says, the EPA cannot approve the single submitted 
contingency measure as meeting both attainment RFP and VOC RFP 
contingency measure requirements. CBD concludes that the EPA must 
propose for comment its theory for how it can reconcile these distinct 
RFP requirements in order to approve the submission as meeting the 
contingency measure requirement for both.
    Response to Comment #1: As the commenter notes, Serious ozone 
nonattainment areas are subject to both the general requirements for 
nonattainment plans in subpart 1, and the specific requirements for 
ozone areas in subpart 2, including the requirements related to RFP and 
contingency measures. This is consistent with the structure of the CAA 
as modified under the 1990 amendments, which introduced additional 
subparts to part D of title I of the CAA to address requirements for 
specific NAAQS pollutants, including ozone (subpart 2), carbon monoxide 
(CO) (subpart 3), particulate matter (subpart 4), and sulfur oxides, 
nitrogen dioxide, and lead (subpart 5).
    These subparts apply tailored requirements for these pollutants, 
including those based on an area's designation and classification, in 
addition to and often in place of the generally applicable provisions 
retained in subpart 1. While CAA 172(c)(2) of subpart 1 states only 
that nonattainment plans ``shall require reasonable further progress,'' 
CAA 182(b)(1) and 182(c)(2)(B) of subpart 2 provide specific percent 
reduction targets for ozone nonattainment areas to meet the RFP 
requirement. Put another way, subpart 2 further defines RFP for ozone 
nonattainment areas by specifying the incremental amount of emissions 
reduction required by set dates for those areas.\28\ In the context of 
section 182(c)(2)(B), the percentage reduction target constitutes an 
RFP ``milestone'' as described in section 182(g), by which the EPA 
determines a Serious ozone nonattainment area's compliance with the RFP 
requirements. For Serious and above ozone nonattainment areas, CAA 
section 182(c)(2)(B) defines RFP by setting specific annual percent 
reductions and allows averaging over a 3-year period, and 182(g) 
establishes an RFP tracking mechanism called a ``milestone'' such that 
failure to meet a milestone equates to failure to meet the RFP 
requirement; they are one and the

[[Page 27527]]

same.\29\ Similarly, while CAA 172(c)(9) establishes the general 
requirement for nonattainment plans to provide contingency measures 
that are triggered in the event that the area fails to make RFP or to 
attain a NAAQS by the applicable attainment date, CAA 182(c)(9) 
specifies that a Serious area nonattainment plan for an ozone NAAQS 
must provide for the implementation of contingency measures to address 
a failure to meet a milestone, which, per the terms of CAA 182(g), is 
the same as failing to make RFP. Likewise, for CO nonattainment areas, 
section 187(a)(3) of subpart 3 addresses contingency measure provisions 
based on consistency between previously projected and actual or 
subsequently projected VMT levels, as well as failure to attain by the 
required deadline. These pollutant-specific contingency measure 
provisions are described in the EPA's General Preamble for the 
Implementation of Title I of the Clean Air Act Amendments of 1990 
(``General Preamble''), which explains that the additional contingency 
measure provisions in subparts 2 and 3 are similar to the general 
contingency measure requirements at CAA 172(c)(9), except that the 
focus is on the planning requirements applicable to ozone and CO.\30\
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    \28\ CAA 171(1) defines reasonable further progress as ``such 
annual incremental reductions in emissions of the relevant air 
pollutant as are required by this part or may reasonably be required 
by the Administrator for the purpose of ensuring attainment of the 
applicable national ambient air quality standard by the applicable 
date.'' As the commenter notes, the words ``this part'' in the 
statutory definition of RFP refer to part D of title I of the CAA, 
which contains both the general requirements in subpart 1 and the 
pollutant-specific requirements in subparts 2-5 (including the 
ozone-specific RFP requirements in CAA 182(b)(1) and 182(c)(2)(B) 
for Serious areas).
    \29\ See CAA 182(g)(1) (explaining that an ``applicable 
milestone'' is the emissions reduction required to be achieved by 
the end of an interval pursuant to the RFP provisions at CAA 
182(b)(1) and the corresponding RFP requirements of 182(c)(2)(B) and 
(C) for Serious areas).
    \30\ 57 FR 13498, 13511 (April 16, 1992).
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    As CBD notes, CAA 182(c)(9) specifies that plans for ozone 
nonattainment areas classified as Serious or above must provide for the 
implementation of contingency measures for failure to meet an ozone RFP 
milestone, ``[i]n addition to the contingency provisions'' required 
under CAA 172(c)(9). The commenter argues that this language requires 
states to submit contingency measures specifically allocated to address 
the section 182(c)(9) RFP milestones, in addition to other separate 
contingency measures to address the general RFP and attainment 
requirements in CAA 172(c)(9). This interpretation is based upon the 
commenter's related interpretation of the subpart 2 RFP milestones as 
distinct requirements separate from the general RFP requirements in 
subpart 1, reflected in the commenter's distinction of ``attainment 
RFP'' and ``VOC RFP.''
    These interpretations run counter to the EPA's longstanding 
approach to the RFP and contingency measure provisions for the ozone 
NAAQS, and we disagree that the statutory text compels the commenter's 
suggested approach. Contrary to the commenter's suggestion, an area 
that is subject to the subpart 2 RFP milestones is not subject to any 
separate milestones or requirements for demonstrating ozone RFP under 
the general RFP provisions in subpart 1. This point is specifically 
addressed in the General Preamble, which specifies that a state that 
meets the specific subpart 2 milestones ``will also satisfy the general 
RFP requirements of section 172(c)(2) for the time period discussed.'' 
\31\ This approach is retained in the implementation rules for the 1997 
and 2008 ozone NAAQS, which specify RFP milestones for ozone 
nonattainment areas that incorporate both the general RFP requirements 
in subpart 1 as well as the ozone-specific RFP requirements in subpart 
2, depending on the area's classification and whether the area already 
has an approved 15 percent rate-of-progress plan for a prior ozone 
NAAQS.\32\
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    \31\ General Preamble, 57 FR 13498, 13510 (for CAA 182(b)(1) 
milestones); id. at 13518 (for 182(c)(2)(B) milestones).
    \32\ 40 CFR 51.1110; see also 70 FR 71612, 71615 (November 29, 
2005); 80 FR 12264, 12271 (March 6, 2015).
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    We disagree with the commenter that the subpart 1 and subpart 2 RFP 
requirements have distinct purposes that require the EPA to establish 
separate milestones or requirements for each. Under either subpart, the 
purpose of RFP is to ensure attainment by the applicable attainment 
date.\33\ As described above, the RFP requirements in CAA 182(b)(1) and 
182(c)(2)(B) define specific RFP milestones applicable to, 
respectively, Moderate and above and Serious and above ozone 
nonattainment areas, for purposes of demonstrating compliance with the 
general RFP requirement at CAA 172(c)(2).
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    \33\ See CAA 171(1); see also 70 FR 71612, 71648 (November 29, 
2005) (``[W]hether dealing with the general RFP requirement of 
section 172(c)(2), or the more specific RFP requirements of subpart 
2 for classified ozone nonattainment areas (i.e., the 15 percent 
plan requirement of section 182(b)(1) and the 3 percent per year 
requirement of section 182(c)(2)), the purpose of RFP is to ensure 
attainment by the applicable attainment date.'').
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    Because there are no separate milestones or requirements for 
demonstrating ozone RFP under the general RFP provisions in subpart 1, 
and because the purposes of RFP are the same under each subpart, we 
similarly disagree with the commenter that a state would be required to 
submit separate contingency measures to address the RFP and milestone 
requirements of subparts 1 and 2. The commenter asserts that the 
language in CAA 182(c)(9) stating the requirements for contingency 
measures in Serious and above ozone nonattainment areas are ``in 
addition to the contingency provisions required under section 
[172(c)(9)]'' refers to both the triggers for contingency measures and 
the contingency measures themselves. In other words, the commenter 
asserts that the EPA must require the state to submit contingency 
measures to address RFP failures under subpart 1 and additional 
contingency measures to address such failures under subpart 2.
    As explained above, CAA 182(c)(9) requires state nonattainment 
plans for Serious and above ozone nonattainment areas to provide for 
the implementation of contingency measures to be undertaken if an area 
fails to meet an applicable milestone, i.e., RFP. Because a 
``milestone,'' as the term is used in CAA section 182(g), is applicable 
only to areas classified as Serious and above, CAA 182(c)(9) represents 
an additional requirement that states must address in an ozone 
nonattainment plan submission for these areas. Section 182(c)(9) 
requires that certain state submissions must provide for the 
implementation of contingency measures in the event of a failure to 
meet a milestone; it does not require the state to submit separate and 
distinct contingency measures allocated exclusively for a failure to 
meet a milestone. Serious and above areas remain subject to the general 
contingency measure requirement described at CAA 172(c)(9), including 
the requirement for contingency measures to take effect in the event of 
a failure to attain the NAAQS by the applicable attainment date (which 
is not provided for in CAA 182(c)(9)), as well as the requirement for 
contingency measures to address a failure to make RFP (i.e., under CAA 
182(c)(9), a failure to meet an applicable milestone under CAA 182(g)). 
CAA 182(c)(9) therefore applies a more specific requirement ``in 
addition to'' the general requirements at CAA 172(c)(9), by 
establishing failure to meet a CAA 182(g) milestone as a specific 
trigger for contingency measures in Serious and above ozone 
nonattainment areas.\34\
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    \34\ As explained above and in the proposed rule, the District 
and CARB have met this requirement by committing to supplement the 
contingency measures element by submitting, within one year of our 
final conditional approval action, a SIP revision that establishes 
contingency measures that will be triggered if the area fails to 
meet an RFP milestone for the 2008 ozone NAAQS or fails to reach 
attainment by the applicable attainment date. See 86 FR 2318, 2320.
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    This is consistent with the EPA's longstanding interpretation of 
the contingency measure requirements, as set out in the General 
Preamble and the

[[Page 27528]]

EPA's implementation rules for the 1997 and 2008 ozone NAAQS. For all 
of the foregoing reasons, this interpretation is reasonable and 
appropriate.
    We also disagree with the commenter's suggestion that the EPA would 
be required to re-propose and take comment on our rationale for 
reconciling the subpart 1 and subpart 2 contingency measures 
requirements. As described above, our approach in this action reflects 
the EPA's longstanding interpretation of the statutory requirements as 
set out in the General Preamble and in the ozone NAAQS implementation 
rules, including the implementation rule for the 2008 ozone NAAQS, for 
which the EPA solicited and received public comment on our proposed 
approaches to RFP, contingency measures, and other topics.
    Comment #2: CBD notes that the milestone provisions at CAA 182(g) 
provide an enforceable tracking and triggering mechanism for subpart 2 
contingency measures, and asserts that because the EPA has conflated 
attainment RFP contingency measures and VOC RFP contingency measures, 
it has not created any separate, enforceable mechanism for tracking and 
triggering the subpart 1 contingency measures. CBD asserts that the EPA 
cannot reasonably approve contingency measures that cannot be 
triggered, and argues that the EPA's failure to provide an enforceable 
tracking and triggering mechanism for the subpart 1 contingency 
measures is an impermissible interpretation of CAA 172(c)(9) because it 
is unmoored from the purposes and concerns of that part. CBD asserts 
that without an enforceable commitment by the state to track and report 
on annual emission reductions, the EPA's discretionary authorities, 
such as a SIP call under CAA 110(k)(5), are inadequate to address this 
failure, and that those authorities do not allow the EPA to trigger the 
subpart 1 contingency measures by determining that attainment RFP has 
not been met.
    Response to Comment #2: Under CAA 172(c)(9), attainment contingency 
measures are triggered by the EPA's finding under CAA 181(b)(2) that an 
area has failed to attain a NAAQS by the applicable attainment date. 
This finding is based on the design value for the area as of the 
attainment date, which represents ambient ozone concentration data 
collected for the area. A finding of failure to attain by the 
attainment date triggers contingency measures to be implemented in the 
area, without further action by the state or the EPA.\35\ Therefore, 
the enforceable tracking and triggering mechanism for attainment 
contingency measures are the EPA's determinations under CAA 181(b)(2) 
regarding whether the ozone nonattainment areas are in attainment by 
their applicable attainment date. Further, contingency measures are 
also triggered by an area's failure to reach an RFP milestone, as 
described by the commenter.
---------------------------------------------------------------------------

    \35\ See General Preamble, 57 FR 13498, 13512.
---------------------------------------------------------------------------

    As explained above, the RFP requirements for the 2008 ozone NAAQS 
are described in the 2008 ozone SRR \36\ and codified at 40 CFR 
51.1110. These requirements incorporate the subpart 1 and subpart 2 RFP 
requirements as they apply to nonattainment areas for the 2008 ozone 
NAAQS, depending on classification and whether the area has an approved 
15 percent rate-of-progress plan for the 1-hour or 1997 ozone NAAQS. 
The percentage reductions described therein represent the applicable 
subpart 1 and subpart 2 obligations for an area to demonstrate RFP for 
the 2008 ozone NAAQS,\37\ and a failure to meet these obligations will 
trigger RFP contingency measures as described above and in the proposed 
rule. Accordingly, we disagree with the commenter that there is not an 
enforceable mechanism for tracking and triggering the RFP contingency 
measures under subpart 1.
---------------------------------------------------------------------------

    \36\ 80 FR 12264, 12263 (March 6, 2015).
    \37\ See General Preamble, 57 FR 13498, 13510 and 13518 
(explaining that an area that meets the RPF milestones specified in 
subpart 2 ``will also satisfy the general RFP requirements of 
section 172(c)(2) for the time period discussed.'').
---------------------------------------------------------------------------

    Comment #3: CBD recounts the backgrounds and outcomes of the Bahr 
decision and the recent Sierra Club decision from the D.C. Circuit 
Court of Appeals,\38\ and discusses policy implications of those 
decisions. CBD also negatively critiques the LEAN decision from the 
Fifth Circuit Court of Appeals,\39\ which the commenter asserts was in 
error.
---------------------------------------------------------------------------

    \38\ Sierra Club v. EPA, 985 F.3d 1055 (D.C. Cir. 2021).
    \39\ Louisiana Environmental Action Network v. EPA, 382 F.3d 575 
(5th Cir. 2004) (``LEAN'') (upholding contingency measures that were 
previously required and implemented where they were in excess of the 
attainment demonstration and RFP SIP).
---------------------------------------------------------------------------

    Response to Comment #3: Our proposed rule explains that we have 
reviewed the contingency measures element of the 2018 Western Nevada 
County Ozone Plan in light of the Bahr decision which is applicable 
within the jurisdiction of the Ninth Circuit Court of Appeals. The more 
recent Sierra Club decision, issued after our proposed rule, is 
consistent with the Bahr decision's treatment of contingency measures. 
For the purposes of our review and action on the 2018 Western Nevada 
County Ozone Plan, we agree that the Bahr and Sierra Club decisions 
govern our review of the contingency measures element.
    Comment #4: CBD notes that longstanding EPA policy states 
contingency measures should equal one year of RFP, and states that the 
EPA is nonetheless proposing to conditionally approve contingency 
measures that fall far short of this amount, based on surplus emission 
reductions from already-implemented measures. CBD asserts that 
consideration of surplus emissions reductions from already-implemented 
measures in evaluating the adequacy of contingency measures is 
functionally no different than simply approving the already-implemented 
measures as contingency measures, which the commenter says is 
inconsistent with the Bahr and Sierra Club decisions.
    CBD views the EPA's consideration of surplus reductions from 
already-implemented measures as relying on a factor Congress has not 
intended the Agency to consider in evaluating the adequacy of 
contingency measures under CAA section 172(c)(9). According to CBD, the 
plain language of sections 172(c)(9) and 182(c)(9), as explained by the 
Bahr and Sierra Club decisions, explicitly limits the factors that the 
EPA may consider by prohibiting use of already implemented measures 
either as de jure or de facto contingency measures. CBD indicates that 
it disagrees with the EPA's response to recent similar comments that 
CBD submitted for our action on the Ventura County 2008 ozone plan.\40\
---------------------------------------------------------------------------

    \40\ 85 FR 38081, 38084 (June 25, 2020).
---------------------------------------------------------------------------

    Response to Comment #4: Neither the CAA nor the EPA's implementing 
regulations for the ozone NAAQS establish a specific amount of 
emissions reductions that implementation of contingency measures must 
achieve. However, consistent with our longstanding guidance, we agree 
that contingency measures should generally provide for emissions 
reductions approximately equivalent to one year's worth of progress, 
which, for Serious ozone nonattainment areas such as Western Nevada 
County, amounts to reductions of 3 percent of the RFP baseline 
emissions inventory for the nonattainment area.
    As we described in the prior response document referenced in this 
comment, in recommending that contingency measures typically achieve 
one year's worth of RFP, the EPA considers the overarching purpose of 
such measures in the context of attainment planning. The purpose of 
emissions reductions

[[Page 27529]]

from implementation of contingency measures is to ensure that, in the 
event of a failure to meet an RFP milestone or a failure to attain the 
NAAQS by the applicable attainment date, the state will continue to 
make progress toward attainment though additional emissions reductions 
at a rate similar to that specified under the RFP requirements. The 
intent is that the state will achieve the emissions reductions from the 
contingency measures while conducting additional control measure 
development and implementation, as necessary to correct the RFP 
shortfall to meet the next applicable milestone or as part of a new 
attainment demonstration plan.\41\ The facts and circumstances of a 
given nonattainment area may justify larger or smaller amounts of 
emissions reductions for contingency measure purposes.
---------------------------------------------------------------------------

    \41\ 57 FR 13498, 13512 (April 16, 1992).
---------------------------------------------------------------------------

    In reviewing a SIP revision for compliance with CAA sections 
172(c)(9) and 182(c)(9), the EPA evaluates whether the contingency 
measure or measures would provide emissions reductions that, when 
considered with surplus emissions reductions from other measures not 
otherwise required or relied upon in the plan, ensure sufficient 
continued progress in the event of a failure to achieve an RFP 
milestone or to attain the ozone NAAQS by the applicable attainment 
date. We continue to evaluate the sufficiency of continued progress 
that will result from contingency measures in light of our guidance, 
but in appropriate circumstances do not believe that the contingency 
measures themselves must provide for one year's worth of RFP. Such 
appropriate circumstances include situations in which sufficient 
progress would be maintained by the contingency measures and surplus 
emissions reductions from other sources, while the state proceeds to 
develop and implement additional control measures as necessary to 
correct the RFP shortfall or as part of a new attainment demonstration 
plan. In other words, if there are additional emissions reductions 
projected to occur after the RFP milestone years or the attainment year 
that a state has not relied upon for purposes of RFP or attainment or 
to meet other nonattainment plan requirements, and that result from 
measures the state has not adopted as contingency measures, then those 
reductions may support EPA approval of contingency measures identified 
by the state even if the contingency measures would result in less than 
one year's worth of RFP in appropriate circumstances.
    We disagree that this approach contradicts Congressional intent. 
The specific explicit factors Congress intended the Agency to use in 
evaluating the contingency measures at issue here are set forth in CAA 
sections 172(c)(9) and 182(c)(9) and include specificity 
(``implementation of specific measures''), timing (``measures to be 
undertaken'' and ``to take effect''), triggers (if the area fails to 
attain the NAAQS by the applicable [NAAQS] or if the area fails to meet 
any applicable milestone), federal enforceability (``included in the 
[SIP]''), and readiness (measures must be designed to take effect 
without further action by the state or the EPA). However, neither CAA 
section 172(c)(9) nor 182(c)(9) contains language implying that these 
are the only factors for the EPA to consider. Neither section specifies 
the magnitude of emissions reductions that contingency measures must 
achieve as an explicit factor for the EPA to consider, although 
consideration of the magnitude is appropriate in determining whether 
the contingency measure or measures submitted by the state meet the 
requirements of CAA sections 172(c)(9) and 182(c)(9). Consideration of 
the magnitude of emissions reductions is appropriate because 
contingency measures serve a remedial function where an area fails to 
achieve an RFP milestone or fails to attain the NAAQS by the applicable 
attainment date, and RFP and attainment are achieved through emissions 
reductions.\42\
---------------------------------------------------------------------------

    \42\ See, e.g., CAA sections 107(d)(3)(E)(iii), 171(1), 
182(c)(1). Under CAA 182(g)(3), in the event that a Serious or 
Severe ozone nonattainment area fails to meet an applicable 
milestone, the state may elect to implement contingency measures 
determined by the EPA as adequate to meet the next milestone, to 
have the area reclassified to the next higher classification, or to 
adopt an economic incentive program. If the state elects to 
implement contingency measures, the EPA may require further measures 
as necessary to meet the next milestone.
---------------------------------------------------------------------------

    Just as the CAA does not include the magnitude of emissions 
reductions as a specific explicit consideration, the CAA also does not 
prescribe how the EPA is to evaluate that question. As such, the EPA is 
not relying on a factor that Congress did not intend the EPA to 
consider when the Agency considers the emissions reductions from 
already-implemented measures that are surplus to those needed for RFP 
or attainment within a given nonattainment area when evaluating whether 
the state's contingency measure submittal meets CAA sections 172(c)(9) 
and 182(c)(9).
    Comment #5: CBD states that the EPA does not say whether the 
surplus emissions reductions considered in evaluating the adequacy of 
contingency measures will remain surplus if the contingency measures 
are triggered. CBD asserts that because these surplus reductions are 
not contingency measures approved into the SIP (which the commenter 
notes would contravene the Bahr decision), the EPA might consider them 
surplus even after the area had failed to make RFP, and use the surplus 
reductions as context to approve inadequate continency measures.
    Response to Comment #5: As described in the proposed rule, the 2018 
Western Nevada County Ozone Plan provides surplus emissions reductions 
from CARB's already-adopted mobile source control program in the two 
RFP milestone years and in the year following the attainment year. 
CARB's estimates of surplus reductions in the RFP milestone years are 
11 to 15 times greater than the amount required to show one year's 
worth of RFP.\43\ In the year after the attainment year, CARB estimates 
that NOX emissions in Western Nevada County will be 
approximately 0.23 tons per day (tpd) lower in 2021 than in the 2020 
attainment year due to mobile source controls and vehicle turnover.\44\ 
On this basis, we found that the District's contingency measures do not 
need to achieve one year's worth of RFP alone, because these 
contingency measures and other surplus emission reductions will ensure 
sufficient continued progress in the event of a failure to achieve an 
RFP milestone or a failure to attain the NAAQS by the applicable 
attainment date. We therefore conditionally approved the Plan based on 
the District's commitment to adopt and submit specific enforceable 
contingency measures as described in letters from the District and 
CARB.
---------------------------------------------------------------------------

    \43\ CARB estimates surplus reductions of 1.9 tpd of 
NOX in 2017 and 2.6 tpd of NOX in 2020, 
compared to the 0.17 tpd of NOX that represents one 
year's worth of RFP. These estimates are derived from the surplus 
percentages listed in Table 4 of the proposed rule (34 percent in 
2017 and 45.9 percent in 2020) multiplied by the 2011 baseline 
NOX emissions level of 5.69 tpd. See 86 FR 2318, 2331.
    \44\ See 86 FR 2318, 2333.
---------------------------------------------------------------------------

    In the event that contingency measures were triggered for failure 
to meet an RFP milestone, the District would be required to adopt new 
contingency measures to take effect in the event of any subsequent 
failure that would trigger a contingency measure.\45\ As described 
above and in the proposed rule, the EPA evaluates any contingency 
measures submission to ensure that the submitted measures will continue 
to

[[Page 27530]]

make progress toward attainment in the event of a milestone or 
attainment failure through additional emissions reductions at a rate 
similar to that specified under the RFP requirements, given the facts 
and circumstances of the nonattainment area. Therefore, an evaluation 
of what emissions reductions are surplus would occur when a new 
contingency measure is submitted, following a failure to meet an RFP 
milestone or a failure to attain by the attainment date.
---------------------------------------------------------------------------

    \45\ See, e.g., General Preamble, 57 FR 13498, 13520 (explaining 
that a state is required to adopt additional measures to replace 
previously used contingency measures, to assure the continuing 
availability of contingency measures).
---------------------------------------------------------------------------

    Comment #6: CBD asserts that the proposed rule approaches arbitrary 
and capricious decision making because it states that it is useful to 
distinguish RFP contingency measures and attainment contingency 
measures but does not apply any relevant distinction between the two. 
CBD asserts that the proposed rule is arbitrary and capricious because 
it abandons a theory from a previous rulemaking that measures the 
adequacy of attainment contingency measures by attempting to predict 
what is necessary to make up a shortfall for a failure to attain 
without providing an explanation. CBD says that the EPA needs to find a 
measure for attainment contingency measures that aligns with the 
statute and is rational. CBD suggests that the EPA could require a 
state to use RACM measures not needed for expeditious attainment as 
contingency measures. CBD notes that these measures might be de 
minimis, and that the EPA could require one year of RFP as a fallback.
    Response to Comment #6: As explained in the proposed rule, for 
purposes of the ozone NAAQS the EPA distinguishes RFP contingency 
measures from attainment contingency measures, respectively, as 
contingency measures to address potential failures to achieve RFP 
milestones and to address potential failure to attain the NAAQS.\46\ 
This distinction is useful for the purposes of evaluating the adequacy 
of the emissions reductions from the contingency measures (once adopted 
and submitted), relative to the facts and circumstances of the area, 
and the anticipated needs to address a shortfall in the relevant years.
---------------------------------------------------------------------------

    \46\ 86 FR 2318, 2333.
---------------------------------------------------------------------------

    CBD's reference to the EPA's theory for measuring the adequacy of 
attainment contingency measures includes a citation to our proposed 
rulemaking for the Sacramento Metro nonattainment area. This appears to 
refer to the EPA's finding for that area that the committed contingency 
measures that served as the basis for our conditional approval were 
projected to be sufficient to correct a failure to attain in less than 
a year from the attainment date, and therefore reflect continued 
progress for purposes of the attainment contingency measure 
requirements.\47\ As described in the proposed rule, the 2018 Western 
Nevada County Ozone Plan shows that reductions from the proposed 
contingency measure, combined with additional emissions reductions from 
other sources that the state does not rely upon to meet other 
requirements in the nonattainment plan in the year following the 
attainment year, will exceed one year's worth of RFP.\48\ For this 
reason and for the reasons described above, we disagree that our 
conditional approval of the attainment contingency measures is 
arbitrary and capricious.
---------------------------------------------------------------------------

    \47\ See 85 FR 68509, 68529 (October 29, 2020). See General 
Preamble, 57 FR 13498, 13511 (explaining that where a failure to 
attain or meet RFP can be corrected in less than one year, the EPA 
may consider contingency measures that are proportionally less than 
one year's worth of RFP sufficient to correct the identified 
failure).
    \48\ 86 FR 2318, 2333 (January 12, 2021).
---------------------------------------------------------------------------

    A described above, we disagree that the EPA's longstanding approach 
to evaluating attainment contingency measures is not rational or does 
not align with the CAA. To CBD's specific suggestion that an area 
should use RACM measures not needed for expeditious attainment as 
contingency measures, we agree that this option may be available to 
some districts and states \49\ but disagree with the commenter's 
suggestion that the EPA would be constrained against approving other 
measures that are consistent with the Act and the EPA's implementing 
regulations with respect to contingency measure requirements.
---------------------------------------------------------------------------

    \49\ See, e.g., 81 FR 58010, 58066 (August 24, 2016) (suggesting 
measures identified as possible RACM or RACT that are not needed for 
expeditious attainment may be suitable as contingency measures).
---------------------------------------------------------------------------

    Comment #7: CBD's Appendix provides numerous comments directed at 
the EPA's NOX Substitution Guidance, contending that the 
EPA's NOX Substitution Guidance is illegitimate. These 
comments assert generally that the NOX Substitution Guidance 
contradicts CAA section 182(c)(2)(C) by recommending a procedure that 
fails to demonstrate any equivalence between VOC and NOX 
reductions, relies on incorrect policy assumptions, and gives legal 
justifications that are without merit.
    Response to Comment #7: Comments relating solely to the 
NOX Substitution Guidance are outside the scope of this 
rulemaking action. As noted in our proposed rule, our approval of the 
District's use of NOX substitution is supported by local 
conditions and needs as documented in the modeling and analysis 
included in the 2018 Western Nevada County Ozone Plan, and is 
consistent with the requirements in CAA section 182(c)(2)(C).

III. Final Action

    No comments were submitted that change our assessment of the 2018 
Western Nevada County Ozone Plan as described in our proposed action. 
Therefore, for the reasons discussed in detail in the proposed rule and 
summarized herein, under CAA section 110(k)(3), the EPA is taking final 
action to approve as a revision to the California SIP the following 
portions of the 2018 Western Nevada County Ozone Plan for the 2008 
ozone NAAQS submitted by CARB on December 7, 2018:
     Base year emissions inventory element as meeting the 
requirements of CAA sections 172(c)(3) and 182(a)(1) and 40 CFR 
51.1115;
     RACM demonstration element as meeting the requirements of 
CAA section 172(c)(1) and 40 CFR 51.1112(c);
     Attainment demonstration element as meeting the 
requirements of CAA section 182(c)(2)(A) and 40 CFR 51.1108;
     ROP demonstration element as meeting the requirements of 
CAA 182(b)(1) and 40 CFR 51.1110(a)(4)(i);
     RFP demonstration element as meeting the requirements of 
CAA sections 172(c)(2), 182(b)(1), and 182(c)(2)(B), and 40 CFR 
51.1110(a)(4)(iii); and
     Motor vehicle emissions budgets for the RFP milestone and 
attainment year of 2020, as shown below, because they are consistent 
with the RFP and attainment demonstrations for the 2008 ozone NAAQS 
approved herein and meet the other criteria in 40 CFR 93.118(e).

 Table 1--Transportation Conformity Budgets for 2020 for the 2008 Ozone
                     NAAQS in Western Nevada County
                    [Summer planning inventory, tpd]
------------------------------------------------------------------------
                                                             2020
                                                     -------------------
                                                         VOC       NOX
------------------------------------------------------------------------
Motor vehicle emissions budget......................      0.8       1.7
------------------------------------------------------------------------
Source: Table 7 of the 2018 Western Nevada County Ozone Plan.

    We are also taking final action to find that the:
     Requirements for enhanced monitoring under CAA section 
182(c)(1) and 40 CFR 51.1102 for Western Nevada County for the 2008 
ozone NAAQS have been met; and

[[Page 27531]]

     The submitted 2020 budgets from the 2018 Western Nevada 
County Ozone Plan are adequate for transportation conformity 
purposes.\50\
---------------------------------------------------------------------------

    \50\ Pursuant to 40 CFR 93.118(f)(2)(iii), the EPA's adequacy 
determination is effective upon publication of this final rule in 
the Federal Register. The proposed rule proposed to find that 
Western Nevada County had met the clean fuels fleet program 
requirements in CAA sections 182(c)(4) and 246 and 40 CFR 51.1102 
for the 2008 ozone NAAQS through the State's 1994 ``Opt-Out 
Program'' SIP revision. However, as explained above, the area is not 
subject to this element because its 1980 population was less than 
250,000.
---------------------------------------------------------------------------

    Lastly, we are conditionally approving, under CAA section 
110(k)(4), the contingency measures element of the 2018 Western Nevada 
County Ozone Plan as meeting the requirements of CAA sections 172(c)(9) 
and 182(c)(9) for RFP and attainment contingency measures. Our approval 
is based on commitments by the District and CARB to supplement the 
element through submission, as a SIP revision (within one year of our 
final conditional approval action), of a District rule that would add 
new limits or other requirements that would apply if an RFP milestone 
is not met or if Western Nevada County fails to attain the 2008 ozone 
NAAQS by the applicable attainment date.\51\
---------------------------------------------------------------------------

    \51\ Letter dated November 16, 2020, from Richard Corey, 
Executive Officer, CARB, to John Busterud, Regional Administrator, 
EPA Region IX. CARB's letter also forwarded the District's 
commitment letter to the EPA. The District's letter is dated October 
26, 2020, from Gretchen Bennitt, NSAQMD Air Pollution Control 
Officer, to Richard Corey, CARB Executive Officer.
---------------------------------------------------------------------------

IV. Statutory and Executive Order Reviews

    Under the Clean Air Act, the Administrator is required to approve a 
SIP submission that complies with the provisions of the Act and 
applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). 
Thus, in reviewing SIP submissions, the EPA's role is to approve state 
choices, provided that they meet the criteria of the Clean Air Act. 
Accordingly, this action merely approves state law as meeting federal 
requirements and does not impose additional requirements beyond those 
imposed by state law. For that reason, this action:
     Is not a significant regulatory action subject to review 
by the Office of Management and Budget under Executive Orders 12866 (58 
FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011);
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of Section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because application of those requirements would be inconsistent 
with the Clean Air Act; and
     Does not provide the 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 the EPA or an Indian tribe 
has demonstrated that a tribe has jurisdiction. In those areas of 
Indian country, the rule does not have tribal implications and will not 
impose substantial direct costs on tribal governments or preempt tribal 
law as specified by Executive Order 13175 (65 FR 67249, November 9, 
2000).
    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the 
Small Business Regulatory Enforcement Fairness Act of 1996, generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report, which includes a copy of the rule, 
to each House of the Congress and to the Comptroller General of the 
United States. The EPA will submit a report containing this action and 
other required information to the U.S. Senate, the U.S. House of 
Representatives, and the Comptroller General of the United States prior 
to publication of the rule in the Federal Register. A major rule cannot 
take effect until 60 days after it is published in the Federal 
Register. This action is not a ``major rule'' as defined by 5 U.S.C. 
804(2).
    Under section 307(b)(1) of the Clean Air Act, petitions for 
judicial review of this action must be filed in the United States Court 
of Appeals for the appropriate circuit by July 20, 2021. Filing a 
petition for reconsideration by the Administrator of this final rule 
does not affect the finality of this action for the purposes of 
judicial review nor does it extend the time within which a petition for 
judicial review may be filed, and shall not postpone the effectiveness 
of such rule or action. This action may not be challenged later in 
proceedings to enforce its requirements. (See section 307(b)(2).)

List of Subjects in 40 CFR Part 52

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

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

    Dated: May 13, 2021.
Deborah Jordan,
Acting Regional Administrator, Region IX.

    For the reasons stated in the preamble, the EPA amends chapter I, 
title 40 of the Code of Federal Regulations as follows:

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

0
1. The authority citation for part 52 continues to read as follows:

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

Subpart F--California

0
2. Section 52.220 is amended by adding paragraph (c)(554) to read as 
follows:


Sec.  52.220  Identification of plan--in part.

* * * * *
    (c) * * *
    (554) The following plan was submitted on December 7, 2018 by the 
Governor's designee.
    (i) [Reserved]
    (ii) Additional materials. (A) Northern Sierra Air Quality 
Management District
    (1) Ozone Attainment Plan, Western Nevada County, State 
Implementation Plan for the 2008 Primary Federal 8-Hour Ozone Standard 
of .075 ppm, adopted on October 22, 2018.
    (2) [Reserved]
    (B) [Reserved]

0
3. Section 52.244 is amended by adding paragraph (a)(12) to read as 
follows:


Sec.  52.244  Motor vehicle emissions budgets.

    (a) * * *
    (12) Nevada County (Western part), approved June 21, 2021.
* * * * *

[[Page 27532]]


0
4. Section 52.248 is amended by adding paragraph (l) to read as 
follows:


Sec.  52.248  Identification of plan--conditional approval.

* * * * *
    (l) The EPA is conditionally approving the California State 
Implementation Plan (SIP) for Nevada County (Western part) for the 2008 
ozone NAAQS with respect to the contingency measures requirements of 
CAA sections 172(c)(9) and 182(c)(9). The conditional approval is based 
on a commitment from the Northern Sierra Air Quality Management 
District (District) in a letter dated October 26, 2020, to adopt a 
specific rule revision, and a commitment from the California Air 
Resources Board (CARB) dated November 16, 2020, to submit the amended 
District rule to the EPA within 12 months of the effective date of the 
final conditional approval. If the District or CARB fail to meet their 
commitments within one year of the effective date of the final 
conditional approval, the conditional approval is treated as a 
disapproval.

[FR Doc. 2021-10510 Filed 5-20-21; 8:45 am]
BILLING CODE 6560-50-P