Document ID: EPA-R09-OAR-2021-0884-0141
Agency: epa
Document Type: Proposed Rule
Title: Air Quality State Implementation Plans; Approvals and Promulgations: Clean Air Plans; 2012 Fine Particulate Matter Serious Nonattainment Area Requirements; San Joaquin Valley, CA
Posted Date: 2022-10-05T04:00Z

[Federal Register Volume 87, Number 192 (Wednesday, October 5, 2022)]
[Proposed Rules]
[Pages 60494-60531]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-21492]

[[Page 60493]]

Vol. 87

Wednesday,

No. 192

October 5, 2022

Part III

Environmental Protection Agency

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40 CFR Part 52

Clean Air Plans; 2012 Fine Particulate Matter Serious Nonattainment 
Area Requirements; San Joaquin Valley, California; Proposed Rule

  Federal Register / Vol. 87 , No. 192 / Wednesday, October 5, 2022 / 
Proposed Rules  

[[Page 60494]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R09-OAR-2021-0884; FRL-9292-03-R9]

Clean Air Plans; 2012 Fine Particulate Matter Serious 
Nonattainment Area Requirements; San Joaquin Valley, California

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: On December 29, 2021, the Environmental Protection Agency (EPA 
or ``Agency'') published a proposed rule to approve the State of 
California's Serious area plan for the San Joaquin Valley (SJV) for the 
2012 annual fine particulate matter (PM2.5) national ambient 
air quality standards (NAAQS) for all Serious PM2.5 area 
planning requirements, except for contingency measures, which the EPA 
proposed to disapprove. Based on adverse comments submitted on that 
proposed rule and as a result of a Ninth Circuit Court of Appeals 
decision on a related SJV PM2.5 rulemaking for the 2006 24-
hour PM2.5 NAAQS, the EPA has reconsidered its prior 
proposal and now proposes to disapprove the State's plan for certain 
Serious area planning requirements for the 2012 annual PM2.5 
NAAQS. The nonattainment plan elements that the EPA proposes to 
disapprove include the plan's best available control measures (BACM) 
demonstration for ammonia and building heating, demonstrations of 
attainment and reasonable further progress, quantitative milestones, 
and motor vehicle emission budgets. The EPA is also proposing to 
disapprove the State's optional precursor demonstration for ammonia. We 
are not re-proposing any action on the Serious area requirements for 
emissions inventories nor contingency measures; our prior proposal to 
approve the emissions inventory element and to disapprove the 
contingency measure element of the nonattainment plan requirements for 
the 2012 annual PM2.5 NAAQS remains unchanged. The EPA will 
accept comments on this new proposed rule during a 45-day public 
comment period and public hearing, as described in this notice.

DATES: Any comments must arrive by November 21, 2022.
    Public hearings: The EPA will host two public hearings on this 
proposed rule. The first will take place November 2, 2022, 7:30 p.m. to 
8:30 p.m. The second will take place November 3, 2022, 7:00 p.m. to 
8:00 p.m. The hearings will be held to accept oral comments on this 
proposed rule. Immediately prior to each public hearing, and on October 
28, 2022, the EPA will host public meetings on this proposed rule. For 
further information on the public hearings and public meetings, please 
see the ADDRESSES and SUPPLEMENTAL INFORMATION sections.

ADDRESSES: The November 2, 2022 public hearing will take place at 
Fresno City College, Old Administration Building, Room 251, 1101 E 
University Ave., Fresno, CA 93741. The November 3, 2022 public hearing 
will take place at Bakersfield College, Norman Levan Center, 1801 
Panorama Drive, Bakersfield, CA 93305.
    Submit your comments, identified by Docket ID No. EPA-R09-OAR-2021-
0884, at https://www.regulations.gov. For comments submitted at 
Regulations.gov, follow the online instructions for submitting 
comments. Once submitted, comments cannot be edited or removed from 
Regulations.gov. The EPA may publish any comment received to its public 
docket. Do not submit electronically any information you consider to be 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Multimedia submissions (audio, 
video, etc.) must be accompanied by a written comment. The written 
comment is considered the official comment and should include 
discussion of all points you wish to make. The EPA will generally not 
consider comments or comment contents located outside of the primary 
submission (i.e., on the web, cloud, or other file sharing system). For 
additional submission methods, 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 https://www.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: For questions regarding this proposed 
rule, please contact Rory Mays, Air Planning Office (AIR-2), EPA Region 
IX, (415) 972-3227. For questions regarding the public hearings and 
related public meetings, please contact Kelley Xuereb, Immediate Office 
(AIR-1), EPA Region IX, (415) 947-4171. Both can be reached by emailing 
[email protected].

SUPPLEMENTARY INFORMATION: In addition to the two in-person public 
hearings, the EPA will host three public meetings. The public meetings 
are an informal opportunity to speak with EPA staff about the action. 
We will not accept public comments during the public meetings. The 
first meeting will be held virtually on October 28, 2022, 12:00 p.m. to 
2:00 p.m. Participants can register to attend the meeting at: https://usepa.zoomgov.com/meeting/register/vJItc-qppzooGCZI10LqoTXf6OpNZIVbWco.
    The second will take place on November 2, 2022, 5:30 p.m. to 7:00 
p.m. prior to the public hearing at Fresno City College, Old 
Administration Building, Room 251, 1101 E University Ave., Fresno, CA 
93741. The third will take place on November 3, 2022, 5:00 p.m. to 6:30 
p.m. prior to the public hearing at Bakersfield College, Norman Levan 
Center, 1801 Panorama Drive, Bakersfield, CA 93305. Spanish translation 
will be available during all three events. If you would like to submit 
a request for reasonable accommodation, please email 
[email protected]. For additional information and updates, 
please visit: https://www.epa.gov/sanjoaquinvalley.
    Throughout this document, ``we,'' ``us,'' and ``our'' refer to the 
EPA.

Table of Contents

I. Background for Proposed Action
    A. Applicable SIP Submissions, Completeness Review, and Clean 
Air Act Requirements
    B. December 29, 2021 Proposed Rule
    C. Adverse Comments Submitted January 28, 2022
    D. Ninth Circuit Decision on Related SJV PM2.5 Plan
II. Reconsideration of the San Joaquin Valley Serious 
PM2.5 Plan
    A. Ammonia Precursor Demonstration
    B. Best Available Control Measures
    C. Attainment Demonstration
    D. Reasonable Further Progress Demonstration and Quantitative 
Milestones
    E. Motor Vehicle Emission Budgets
III. Environmental Justice Considerations
IV. Title VI of the Civil Rights Act
    A. Background on CAA Section 110(a)(2)(E)
    B. Background on Title VI of the Civil Rights Act of 1964
    C. Comments Received on 2021 Proposed Rule
V. Summary of Proposed Actions and Request for Public Comment
VI. Statutory and Executive Order Reviews

I. Background for Proposed Action

    The EPA discussed background, applicable State implementation plan 
(SIP) submissions, completeness review, and Clean Air Act (CAA or 
``Act'') requirements for the SJV Serious PM2.5

[[Page 60495]]

nonattainment area \1\ in sections I, II, and III of our December 29, 
2021 proposed rule on California's Serious area plan for the 2012 
annual PM2.5 NAAQS.\2\ We refer to that proposed rule herein 
as the ``2021 Proposed Rule,'' briefly summarize the relevant CAA 
requirements and our previous proposed action with respect to those 
requirements here, and rely on the more detailed expositions in that 
proposed rule.
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    \1\ For a precise description of the geographic boundaries of 
the SJV PM2.5 nonattainment area, see 40 CFR 81.305.
    \2\ 86 FR 74310 (December 29, 2021).
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    The EPA promulgated the primary annual PM2.5 NAAQS of 
12.0 micrograms per cubic meter ([micro]g/m\3\) in 2012 (``2012 annual 
PM2.5 NAAQS''),\3\ designated and classified the SJV as 
Moderate nonattainment for this NAAQS in 2015,\4\ and reclassified the 
SJV from Moderate to Serious nonattainment for this NAAQS in our final 
rule published November 26, 2021.\5\ That reclassification action 
required California to submit a ``Serious area'' attainment plan. Such 
an attainment plan must include, among other things, provisions to 
assure that, under CAA section 189(b)(1)(B), the BACM for the control 
of direct PM2.5 and PM2.5 precursors are 
implemented no later than four years after reclassification of the area 
and a demonstration (including air quality modeling) that the plan 
provides for attainment of this NAAQS as expeditiously as practicable 
but no later than December 31, 2025. That reclassification action also 
triggered statutory deadlines for California to submit SIP submissions 
addressing the Serious area attainment plan requirements for the 2012 
annual PM2.5 NAAQS: June 27, 2023, for emissions 
inventories, BACM, and nonattainment new source review (NSR), and 
December 31, 2023, for the attainment demonstration and related 
planning requirements.
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    \3\ 78 FR 3086 (January 15, 2013) and 40 CFR 50.18. Unless 
otherwise noted, all references to the PM2.5 standards in 
this notice, including all instances of ``2012 annual 
PM2.5 NAAQS,'' are to the 2012 primary annual NAAQS of 
12.0 [micro]g/m\3\ codified at 40 CFR 50.18.
    \4\ 80 FR 2206 (January 15, 2015) (codified at 40 CFR 81.305).
    \5\ 86 FR 67343 (November 26, 2021).
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A. Applicable SIP Submissions, Completeness Review, and Clean Air Act 
Requirements

    In this proposed rule, the EPA is proposing action on portions of 
two SIP submissions submitted by the California Air Resources Board 
(CARB) to address combined nonattainment plan requirements for the 
1997, 2006, and 2012 PM2.5 NAAQS in the SJV.\6\ 
Specifically, the EPA is proposing to act only on those portions of the 
following two plan submissions that pertain to the Serious area 
requirements for the 2012 annual PM2.5 NAAQS: (1) the ``2018 
Plan for the 1997, 2006, and 2012 PM2.5 Standards,'' adopted 
by the San Joaquin Valley Unified Air Pollution Control District 
(SJVUAPCD or District) on November 15, 2018, and by CARB on January 24, 
2019 (``2018 PM2.5 Plan''); \7\ and (2) the ``San Joaquin 
Valley Supplement to the 2016 State Strategy for the State 
Implementation Plan,'' adopted by CARB on October 25, 2018 (``Valley 
State SIP Strategy'').
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    \6\ In our 2021 Proposed Rule, we also proposed action on a 
third SIP submission dated July 19, 2019. 86 FR 74310, 74311. 
However, the relevant component of that submission pertained only to 
contingency measures, and we are not modifying our proposed action 
on contingency measures in this proposed rule.
    \7\ The 2018 PM2.5 Plan was developed jointly by CARB 
and the District.
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    We refer to the relevant portions of these SIP submissions 
collectively in this proposal as the ``SJV PM2.5 Plan'' or 
``Plan.'' The SJV PM2.5 Plan addresses attainment plan 
requirements for multiple PM2.5 NAAQS in the SJV. CARB 
submitted the SJV PM2.5 Plan to the EPA as a revision to the 
California SIP on May 10, 2019.\8\ These SIP submissions became 
complete by operation of law on November 10, 2019.\9\ In the 2021 
Proposed Rule, we proposed to find that the 2018 PM2.5 Plan 
and Valley State SIP Strategy each met the procedural requirements for 
public notice and hearing in CAA sections 110(a)(1) and (2) and 110(l) 
and 40 CFR 51.102.
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    \8\ Letter dated May 9, 2019, from Richard W. Corey, Executive 
Officer, CARB, to Mike Stoker, Regional Administrator, EPA Region 
IX. Previously, in separate rulemakings, the EPA has finalized 
action on the portions of the SJV PM2.5 Plan that pertain 
to the 1997 annual PM2.5 NAAQS, the 1997 24-hour 
PM2.5 NAAQS, the 2006 24-hour PM2.5 NAAQS, and 
the Moderate area plan for the 2012 annual PM2.5 NAAQS. 
See 86 FR 67329 (November 26, 2021) (final rule regarding the 1997 
annual PM2.5 NAAQS); 87 FR 4503 (January 28, 2022) (final 
rule regarding the 1997 24-hour PM2.5 NAAQS); 85 FR 44192 
(July 22, 2020) (final rule regarding the 2006 24-hour 
PM2.5 NAAQS, except contingency measures); and 86 FR 
67343 (November 26, 2021) (final rule regarding the Moderate area 
plan for the 2012 annual PM2.5 NAAQS and contingency 
measures for the 2006 24-hour PM2.5 NAAQS).
    \9\ 87 FR 74310, 74311-74312. We note that, with respect to 
plans previously required for the 1997, 2006, and 2012 
PM2.5 NAAQS, including the Moderate area plan only for 
the 2012 annual PM2.5 NAAQS, the EPA had made findings of 
failure to submit effective January 7, 2019, that triggered 
sanctions clocks. 83 FR 62720 (December 6, 2018). Following the May 
10, 2019 submission of the 2018 PM2.5 Plan and Valley 
State SIP Strategy, the EPA affirmatively determined that the SIP 
submissions addressed the deficiency that was the basis for such 
findings, resulting in the termination of the associated sanctions 
clocks. Letter dated June 24, 2020, from Elizabeth Adams, Director, 
Air and Radiation Division, EPA Region IX, to Richard W. Corey, 
Executive Officer, CARB. However, the findings of failure to submit 
did not apply to the Serious area plan for the 2012 annual 
PM2.5 NAAQS because it was not yet required, and the June 
24, 2020 completeness letter did not address the Serious area plan 
for the 2012 annual PM2.5 NAAQS.
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    In our 2021 Proposed Rule, we also summarized the CAA requirements 
applicable to Serious PM2.5 nonattainment areas.\10\ In the 
current proposed rule, we are proposing action with respect to the 
following requirements:
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    \10\ 87 FR 74310, 74313.
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    (1) Provisions to assure that BACM, including best available 
control technology (BACT), for the control of direct PM2.5 
and all PM2.5 precursors shall be implemented no later than 
four years after the area is reclassified (CAA section 189(b)(1)(B)), 
unless the State elects to make an optional precursor demonstration 
that the EPA approves authorizing the State not to regulate one or more 
of these pollutants;
    (2) A demonstration (including air quality modeling) that the plan 
provides for attainment as expeditiously as practicable but no later 
than the end of the tenth calendar year after designation as a 
nonattainment area (i.e., December 31, 2025, for the SJV for the 2012 
annual PM2.5 NAAQS) (CAA sections 188(c)(2) and 
189(b)(1)(A)(i));
    (3) Plan provisions that require reasonable further progress (RFP) 
(CAA section 172(c)(2));
    (4) Quantitative milestones that the State must meet every three 
years until the EPA redesignates the area to attainment and which 
demonstrate RFP toward attainment by the applicable date (CAA section 
189(c)); and
    (5) Motor vehicle emissions budgets (budgets) for 2025 (CAA section 
176(c)).
    We are also proposing to disapprove the State's optional precursor 
demonstration for ammonia.\11\
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    \11\ We are not re-proposing any action on the Serious area 
requirements for emissions inventories nor contingency measures; our 
prior proposal to approve the emissions inventory element and to 
disapprove the contingency measure element of the nonattainment plan 
requirements for the 2012 annual PM2.5 NAAQS remains 
unchanged.
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    In addition, the State's Serious area plan must meet the general 
requirements applicable to all SIP submissions under section 110 of the 
CAA, including the requirement to provide necessary assurances that the 
implementing agencies have adequate personnel, funding, and authority 
under section 110(a)(2)(E); and the requirements concerning enforcement 
provisions in section 110(a)(2)(C).

[[Page 60496]]

    The EPA provided its preliminary views on the CAA's requirements 
for particulate matter plans under part D, title I of the Act in the 
following guidance documents: (1) ``State Implementation Plans; General 
Preamble for the Implementation of Title I of the Clean Air Act 
Amendments of 1990'' (``General Preamble''); \12\ (2) ``State 
Implementation Plans; General Preamble for the Implementation of Title 
I of the Clean Air Act Amendments of 1990; Supplemental'' (``General 
Preamble Supplement''); \13\ and (3) ``State Implementation Plans for 
Serious PM-10 Nonattainment Areas, and Attainment Date Waivers for PM-
10 Nonattainment Areas Generally; Addendum to the General Preamble for 
the Implementation of Title I of the Clean Air Act Amendments of 1990'' 
(``General Preamble Addendum'').\14\ More recently, in an August 24, 
2016 final rule entitled, ``Fine Particulate Matter National Ambient 
Air Quality Standards: State Implementation Plan Requirements'' 
(``PM2.5 SIP Requirements Rule''), the EPA established 
regulatory requirements and provided further interpretive guidance on 
the statutory SIP requirements that apply to areas designated 
nonattainment for all PM2.5 NAAQS.\15\ We discuss these 
regulatory requirements and interpretations of the Act as appropriate 
in our evaluation of the State's submissions below.
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    \12\ 57 FR 13498 (April 16, 1992).
    \13\ 57 FR 18070 (April 28, 1992).
    \14\ 59 FR 41998 (August 16, 1994).
    \15\ 81 FR 58010 (August 24, 2016).
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B. December 29, 2021 Proposed Rule

    In our 2021 Proposed Rule, the EPA proposed to approve the SJV 
PM2.5 Plan's: (1) emissions inventory for the 2013 base 
year; (2) precursor demonstrations that emissions of ammonia, sulfur 
oxides (SOX), and volatile organic compounds (VOC) do not 
significantly contribute to exceedances of the 2012 annual 
PM2.5 NAAQS in the SJV; (3) BACM demonstration for emission 
sources of direct PM2.5 and nitrogen oxides 
(NOX); (4) attainment demonstration based on air quality 
modeling \16\ and emissions reductions related to aggregate 
commitments; (5) RFP demonstration; (6) quantitative milestones; and 
(7) motor vehicle emission budgets. We briefly summarize several 
aspects of those proposed approvals in the applicable sub-sections of 
section II of this proposed rule.
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    \16\ We described 2018 PM2.5 Plan's air quality 
modeling and our evaluation thereof in section IV.C of the 2021 
Proposed Rule.
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    We also proposed to disapprove the Plan's contingency measures and 
noted the requirements for nonattainment NSR and the State's separate 
submission for the nonattainment NSR requirements. However, as we are 
not re-proposing any action on contingency measures nor nonattainment 
NSR in this proposed rule, we do not summarize those proposals 
herein.\17\ In addition, we are not re-proposing any action on the 
Plan's precursor demonstrations for SOX and VOC in this 
proposed rule; our 2021 Proposed Rule to approve the 2018 
PM2.5 Plan's demonstrations that emissions of SOX 
and VOC do not significantly contribute to exceedances of the 2012 
annual PM2.5 NAAQS in the SJV remains unchanged.
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    \17\ Regarding nonattainment NSR, please see the EPA's separate 
rulemaking on the State's November 20, 2019 SIP submission of 
amendments to SJVUAPCD Rule 2201 (``New and Modified Stationary 
Source Review''). 87 FR 45730 (July 29, 2022) (proposed limited 
approval and limited disapproval of the Rule 2201 amendments).
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    Finally, we are not re-proposing any action in this proposed rule 
on the Plan's base year emissions inventory; our 2021 Proposed Rule to 
approve the 2018 PM2.5 Plan's base year emissions inventory 
remains unchanged. Nevertheless, we briefly summarize our prior 
proposal \18\ given the role that base year emissions inventories play 
in developing a plan's control strategy and attainment and RFP 
demonstrations.
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    \18\ See section IV.A of the EPA's 2021 Proposed Rule.
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    The 2018 PM2.5 Plan includes summaries of the planning 
emissions inventories for direct PM2.5 and all 
PM2.5 precursors (NOX, SOX,\19\ 
VOC,\20\ and ammonia) and related documentation. The Plan contains 
annual average daily emission inventories for 2013 through 2028 
projected from the 2012 actual emissions inventory,\21\ including the 
2013 base year, the 2019 and 2022 RFP milestone years, the 2025 Serious 
area attainment year, and a 2028 post-attainment RFP year. The EPA 
proposed to approve the 2013 base year emissions inventory in the 2018 
PM2.5 Plan as meeting the requirements of CAA section 
172(c)(3) and 40 CFR 51.1008. We also proposed to find that the future 
year baseline inventories in the 2018 PM2.5 Plan satisfy the 
requirements of 40 CFR 51.1008(b)(2) and 51.1012(a)(2) and provide an 
adequate basis for the control measure, attainment, and RFP 
demonstrations for the 2012 annual PM2.5 NAAQS in the 2018 
PM2.5 Plan.
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    \19\ The SJV PM2.5 Plan generally uses ``sulfur 
oxides'' or ``SOX'' in reference to SO2 as a 
precursor to the formation of PM2.5. We use 
SOX and SO2 interchangeably throughout this 
notice.
    \20\ The SJV PM2.5 Plan generally uses ``reactive 
organic gasses'' or ``ROG'' in reference to VOC as a precursor to 
the formation of PM2.5. We use ROG and VOC 
interchangeably throughout this notice.
    \21\ 2018 PM2.5 Plan, App. B, B-18.
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C. Adverse Comments Submitted January 28, 2022

    The EPA received adverse comments on our 2021 Proposed Rule from a 
coalition of 13 environmental, public health, and community 
organizations (collectively referred to herein as ``Public 
Justice'').\22\ We are not responding to these comments (in the sense 
of a final rulemaking action) in this proposed rule, but the Agency has 
taken them into account with respect to the Serious area plan elements 
discussed in this proposed rule.
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    \22\ Comment letter dated and received January 28, 2022, from 
Brent Newell, Public Justice, et al., to Rory Mays, EPA, including 
Exhibits 1 through 47. We note, however, that there is no Exhibit 
23; so, there are 46 exhibits in total. Email dated February 1, 
2022, from Brent Newell, Public Justice, to Rory Mays, EPA Region 
IX. The 13 environmental, public health, and community organizations 
are Public Justice, Central Valley Environmental Justice Network, 
Association of Irritated Residents, Central Valley Air Quality 
Coalition, Leadership Counsel for Justice and Accountability, Valley 
Improvement Projects, The LEAP Institute, Little Manila Rising, 
Center for Race, Poverty, and the Environment, Central California 
Asthma Collaborative, Animal Legal Defense Fund, National Parks 
Conservation Association, and Food and Water Watch (collectively 
``Public Justice'').
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    Overall, the commenters argue that the EPA must disapprove the 2012 
annual PM2.5 NAAQS portion of the SJV PM2.5 Plan 
based on alleged nonattainment plan requirement deficiencies in the 
submissions. We introduce these comments in this section of this 
proposed rule and present more detailed summaries and discussion of the 
comments in sections II.A (ammonia precursor demonstration), II.B.2 
(BACM for ammonia emission sources), II.B.3 (BACM for building heating 
emission sources), II.C (attainment demonstration), and IV (Title VI of 
the Civil Rights Act).
    Regarding CAA requirements for PM2.5, Public Justice 
points to a history of failures to timely attain the 1997 annual 
PM2.5 NAAQS in the SJV and states that ``[r]egulators point 
to a host of excuses from weather, to international sources, to Federal 
inaction, but repeatedly the State and Air District have refused to 
adopt feasible controls or regulate politically powerful entities'' 
such as agricultural sources of air pollution.\23\ The commenters take 
issue with the EPA's proposal to approve the plan for the stricter 2012 
standard ``without performing its duty to hold [CARB] and the 
[District] accountable to meet the

[[Page 60497]]

minimum requirements Congress imposed to protect human health.'' \24\ 
The commenters assert that the EPA relies on flawed, outdated 
information, ignores feasible controls, refuses to require regulation 
of ammonia, accepts aggregate commitments in lieu of other control 
strategies, and fails to address pollution sources in disadvantaged 
communities in the SJV.\25\ With respect to specific CAA requirements, 
the commenters argue that the EPA must disapprove the Plan's emissions 
inventory, ammonia precursor demonstration, BACM demonstration, and 
aggregate commitments.
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    \23\ Public Justice Comment Letter, 2.
    \24\ Id.
    \25\ Id. at 3.
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    Regarding Title VI of the Civil Rights Act, the commenters argue 
that California must provide necessary assurances that the SIP complies 
with Title VI of the Civil Rights Act, pursuant to CAA section 
110(a)(2)(E), and failed to do so.\26\ The commenters state that 
``PM2.5 pollution has a disparate impact on the basis of 
race in the San Joaquin Valley'' and assert that the Plan fails to meet 
CAA requirements and ``deliberately ignores obvious sources and control 
options and inflicts disparate impacts on Black, Latino, Indigenous, 
and people of color'' in the SJV. Therefore, the commenters advocate 
that the EPA must disapprove the 2012 annual PM2.5 portion 
of the SJV PM2.5 Plan.\27\ We address the commenters' Title 
VI comments in section IV of this proposed rule.
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    \26\ Id. at 10-14.
    \27\ Id. at 1 and 21.
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    The EPA is now proposing to disapprove the Plan with respect to 
certain CAA requirements (BACM/BACT for ammonia emission sources, BACM/
BACT for building heating emission sources, aggregate commitments, 
attainment demonstration, RFP demonstration, quantitative milestones, 
and motor vehicle emission budgets). However, we are not in this 
proposal comprehensively addressing all issues raised in the Public 
Justice comment letter.\28\
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    \28\ Additional source categories named by Public Justice 
include, for example, residential wood burning, open burning, 
conservation management practices at farming operations, soil 
NOX emissions, stationary agricultural internal 
combustion engines, and cleaner mobile agricultural equipment 
engines. Public Justice Comment Letter, 18-20.
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D. Ninth Circuit Decision on Related SJV PM2.5 Plan

    In a final rule published July 22, 2020, the EPA finalized approval 
of the portions of the SJV PM2.5 Plan \29\ that addressed 
the 2006 24-hour PM2.5 NAAQS (except for contingency 
measures, which the EPA acted on in a subsequent action).\30\ On 
September 17, 2020, a group of five environmental, public health, and 
community groups (collectively referred to herein as ``Medical 
Advocates'') petitioned the Ninth Circuit Court of Appeals (``Ninth 
Circuit'' or ``Court'') for review of the EPA's July 22, 2020 final 
rule.\31\ On April 13, 2022, the Ninth Circuit issued a Memorandum 
opinion that granted in part and denied in part the petition 
(``Memorandum Opinion'').\32\
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    \29\ 85 FR 44192.
    \30\ 86 FR 67343 (disapproving contingency measures for the 2006 
24-hour PM2.5 NAAQS).
    \31\ Medical Advocates for Healthy Air v. EPA, Case No. 20-
72780, Dkt. #1 (9th Cir., September 17, 2020). The five 
environmental, public health, and community organizations, in order 
of appearance in the petition, are Medical Advocates for Healthy 
Air, National Parks Conservation Association, Association of 
Irritated Residents, and Sierra Club (collectively ``Medical 
Advocates'').
    \32\ Medical Advocates for Healthy Air v. EPA, Case No. 20-
72780, Dkt. #58-1 (9th Cir., April 13, 2022).
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    The Ninth Circuit denied the petitioners' challenge with respect to 
the EPA's approval of enforceable commitments in general and the EPA's 
approval of the Plan's demonstration of BACM, BACT, and most stringent 
measures (MSM) for emission sources of direct PM2.5 and 
NOX for purposes of the 2006 24-hour PM2.5 NAAQS.
    Significantly, however, the Ninth Circuit also denied in part and 
granted in part the petitioners' challenge with respect to the EPA's 
approval of the specific enforceable commitments employed as part of 
the SJV PM2.5 Plan's control strategy to attain the 2006 24-
hour PM2.5 NAAQS in the SJV by December 31, 2024. The EPA 
evaluates enforceable commitments based on three factors: (1) the 
commitment represents a limited portion of the required emission 
reductions, (2) the State is capable of fulfilling its commitment, and 
(3) the commitment is for a reasonable and appropriate timeframe. The 
Ninth Circuit denied the petitioners' challenge with respect to the 
first and third factors but granted the petitioners' challenge with 
respect to the second factor.
    The Ninth Circuit found that the EPA had misapplied the second 
factor concerning the State's ability to fulfill the aggregate 
commitments. The Court reasoned that EPA ``fail[ed] to provide evidence 
or a reasoned explanation for its conclusion that California will be 
able to fulfill its commitment'' in the face of a potential multi-
billion dollar funding shortfall for incentive-based control measure 
commitments, ``which could result in emission reduction shortfalls of 
approximately 7% of the total NOX reductions and 8% of the 
total PM2.5 reductions necessary for attainment.'' \33\ The 
Court also rejected the EPA's arguments that: (1) the funding shortfall 
may be smaller than projected, (2) emission reductions may be less 
expensive than the strategy predicts, (3) certain yet-to-be-quantified 
sources of reductions in the Plan may make up for shortfalls, and (4) 
California and the District may identify other measures to fulfill 
their commitments. Instead, the Court decided that, ``[b]ecause these 
speculative assertions are unsupported by the evidence, they fail to 
ensure that California and the District have a plausible strategy for 
achieving this portion of the attainment strategy, and therefore do not 
collectively satisfy the second factor of the EPA's three-factor 
test.'' \34\ The Court concluded that the EPA's analysis with respect 
to the second factor for evaluating enforceable commitments was 
arbitrary and capricious, vacated the final rule with respect to this 
factor, and remanded the matter to the EPA for further consideration of 
the second factor.\35\
---------------------------------------------------------------------------

    \33\ Id. at 6.
    \34\ Id. at 7.
    \35\ Id. at 10.
---------------------------------------------------------------------------

    The EPA is currently considering how to address the Court's vacatur 
and remand with respect to the 2006 24-hour PM2.5 NAAQS 
portion of the SJV PM2.5 Plan and is not proposing any 
action with respect to those standards in this proposed rule. However, 
the Ninth Circuit's decision is very relevant to this proposed rule 
because the State relied on a common control strategy, including the 
same enforceable commitments (i.e., the same set of control measure 
commitments and aggregate tonnage commitments) for purposes of both the 
2006 24-hour PM2.5 NAAQS Serious area plan and the 2012 
annual PM2.5 NAAQS Serious area plan. The EPA acknowledges 
the deficiency in the factual support for the aggregate commitments 
identified by the Ninth Circuit and that this remains the case. If the 
EPA cannot approve the aggregate commitments, then this has a direct 
bearing on other elements of the State's Serious area SIP submissions 
for the 2012 annual PM2.5 NAAQS. As discussed in section 
II.C of this proposed rule, based on our reconsideration of the facts 
concerning the enforceable commitments in the SJV PM2.5 Plan 
with respect to the 2012 annual PM2.5 NAAQS in light of the 
Ninth Circuit's decision, the EPA now proposes to disapprove the 
State's enforceable commitments and attainment demonstration.

[[Page 60498]]

II. Reconsideration of the San Joaquin Valley Serious PM2.5 Plan

    The EPA has reconsidered its 2021 Proposed Rule, based on adverse 
comments on that prior proposal and based on a Ninth Circuit Court of 
Appeals decision on a related SJV PM2.5 rulemaking. After 
careful consideration of the issues raised by commenters and the court, 
the EPA now proposes to disapprove the State's plan for the 2012 annual 
PM2.5 NAAQS in the SJV for certain Serious area planning 
requirements, including: (1) the Plan's precursor demonstration for 
ammonia; (2) BACM for ammonia emission sources and BACM for building 
heating emission sources; (3) the modeled attainment demonstration; (4) 
the RFP demonstration; (5) quantitative milestones; and (6) motor 
vehicle emission budgets.
    In sections II.A through II.C of this proposed rule, pertaining to 
the Plan's precursor demonstration for ammonia as a PM2.5 
precursor; BACM/BACT analysis, and modeled attainment demonstration 
(including reliance on enforceable commitments), we present a brief 
summary of the 2021 Proposed Rule, a summary of the adverse comments 
and Ninth Circuit order, as appropriate, and our reconsidered proposal. 
In sections II.D and II.E, pertaining to the Plan's RFP demonstration, 
quantitative milestones, and motor vehicle emission budgets, we present 
a brief summary of the 2021 Proposed Rule and our reconsidered 
proposal.\36\ We also note that sections II.A (ammonia precursor 
demonstration) and II.B.1 (BACM for ammonia emission sources) are 
inter-related in that potential control measures for ammonia emission 
sources play a role in both: (1) selecting a reasonable percent 
emission reduction to evaluate modeled ambient PM2.5 
responses to ammonia emission reductions; and (2) assessing the 
availability and application of BACM to such sources in the SJV.
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    \36\ The Plan's RFP demonstration, quantitative milestones, and 
motor vehicle emission budgets were not the direct subject of 
adverse comments nor the Ninth Circuit decision. However, they are 
based on the Plan's control strategy to attain the 2012 annual 
PM2.5 NAAQS and, thus, the flaws in the Plan's control 
strategy affect these additional required elements.
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A. Ammonia Precursor Demonstration

1. Summary of 2021 Proposed Rule
    In our 2021 Proposed Rule, the EPA described the requirements for 
PM2.5 precursor pollutants, summarized the State's 
submissions in the SJV PM2.5 Plan, and presented our 
evaluation thereof.\37\ We briefly summarize those here with respect to 
the Plan's demonstration for ammonia as a precursor to PM2.5 
for purposes of the 2012 annual PM2.5 NAAQS in the SJV. For 
a comprehensive discussion of Federal requirements for PM2.5 
precursors and a summary of California's submission, please refer to 
the following headings in Section IV.B of the 2021 Proposed Rule: (1) 
Requirements for Control of PM2.5 Precursors; and (2) 
Summary of State's Submission.
---------------------------------------------------------------------------

    \37\ 86 FR 74310, 74317-74321.
---------------------------------------------------------------------------

    Regarding CAA requirements applicable to PM2.5 
precursors, we explained that the attainment plan requirements of Title 
I, subpart 4 apply to emissions of direct PM2.5 and 
emissions of NOX, ammonia, SO2, and VOC as 
PM2.5 precursors from all types of stationary, area, and 
mobile sources, except as otherwise provided in the Act. We further 
described how the EPA interprets section 189(e) concerning regulation 
of precursors from major stationary sources to authorize it to 
determine, under appropriate circumstances, that regulation of specific 
PM2.5 precursors from other sources in a given nonattainment 
area is not necessary.
    As explained in the PM2.5 SIP Requirements Rule, a State 
may elect to submit to the EPA a ``comprehensive precursor 
demonstration'' for a specific nonattainment area to show that 
emissions of a particular precursor from existing sources located in 
the nonattainment area do not contribute significantly to 
PM2.5 levels that exceed the standard in the area.\38\ The 
contribution analysis may consider the sensitivity of PM2.5 
to decreases in emissions of the precursor, in addition to the 
contribution to ambient concentrations of PM2.5.\39\ If the 
EPA determines that the contribution of the precursor to 
PM2.5 levels in the area is not significant and approves the 
demonstration, then the State is not required to control emissions of 
the relevant precursor in the attainment plan.\40\
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    \38\ 40 CFR 51.1006(a)(1).
    \39\ 40 CFR 51.1006(a)(1)(ii).
    \40\ 40 CFR 51.1006(a)(1)(iii).
---------------------------------------------------------------------------

    The EPA issued the ``PM2.5 Precursor Demonstration 
Guidance'' (``PM2.5 Precursor Guidance''),\41\ to provide 
recommendations to states for analyzing nonattainment area 
PM2.5 and PM2.5 precursor emissions and 
developing such optional precursor demonstrations, consistent with the 
PM2.5 SIP Requirements Rule. The guidance also describes how 
the State may use a sensitivity-based test, in which the modeled 
sensitivity or response of ambient PM2.5 concentrations to 
changes in emissions of the precursor is estimated and then compared to 
a contribution threshold. In addition to comparing the concentration or 
modeled response to the threshold, the State can consider other 
information in assessing whether the precursor significantly 
contributes. The EPA's recommended annual average contribution 
threshold for the 2012 annual PM2.5 NAAQS is 0.2 [micro]g/
m\3\.\42\ In other words, if the estimated contribution of a precursor 
at monitors is below this threshold, the EPA considers this evidence 
that the precursor does not contribute significantly to levels above 
the PM2.5 NAAQS in the area in question; above this 
threshold, the EPA considers this evidence that the precursor does 
contribute significantly. The EPA considers this evidence in 
conjunction with additional information that the State may provide, and 
determines whether or not the precursor contributes significantly, and 
so whether the State must evaluate and implement controls of the 
precursor emissions to the appropriate level (e.g., BACM).
---------------------------------------------------------------------------

    \41\ ``PM2.5 Precursor Demonstration Guidance,'' EPA-
454/R-19-004, May 2019, including Memo dated May 30, 2019, from 
Scott Mathias, Acting Director, Air Quality Policy Division and 
Richard Wayland, Director, Air Quality Assessment Division, Office 
of Air Quality Planning and Standards (OAQPS), EPA to Regional Air 
Division Directors, Regions 1-10, EPA.
    \42\ PM2.5 Precursor Guidance, 17.
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    The State presents its precursor demonstration primarily in 
Appendix G of the 2018 PM2.5 Plan, with additional 
clarifying information in a series of emails available in the docket 
for this proposed rule. The State estimates that anthropogenic 
emissions of NOX, ammonia, SOX, and VOC will 
decrease by 64 percent (%), 1%, 6%, and 9%, respectively, between 2013 
and 2025 based on its projected emissions accounting for existing and 
additional control measures in the Serious area plan.\43\ Through a 
concentration-based analysis, CARB found that ammonium nitrate 
constituted 5.2 [micro]g/m\3\ of the annual average PM2.5 
concentrations measured at the Bakersfield California Avenue monitor in 
2015, exceeding the recommended threshold,\44\ and proceeded to conduct 
a sensitivity-based analysis.
---------------------------------------------------------------------------

    \43\ 2018 PM2.5 Plan, Ch. 7, 7-5 and Table 7-2.
    \44\ 2018 PM2.5 Plan, App. G, 3.
---------------------------------------------------------------------------

    For analytical purposes in accordance with the EPA's guidance, the 
State then modeled the sensitivity of ambient PM2.5 to 
hypothetical 30% and 70% reductions in anthropogenic emissions of 
ammonia in SJV for modeled years

[[Page 60499]]

2013, 2020, and 2024. The results for 2024 are a proxy for the Plan's 
modeled attainment year of 2025 for the 2012 annual PM2.5 
NAAQS. For the 30% reduction results for 2024, upon which the State 
primarily relied, 2 out of 15 monitoring sites in SJV (Madera and 
Hanford) had modeled responses to ammonia reductions that were above 
the threshold. The ambient PM2.5 response declines 
substantially from 2020 to 2024, with the decline being generally 
larger for the sites with the highest projected PM2.5 
levels. The State supplements the sensitivity analysis for ammonia with 
consideration of additional information such as emission trends, the 
appropriateness of future year versus base year sensitivity, available 
emission controls, and the severity of nonattainment.\45\
---------------------------------------------------------------------------

    \45\ Id. at App. G, 5.
---------------------------------------------------------------------------

    The State's precursor demonstration for ammonia also presents a 
review of District agricultural rules that control VOC emissions, but 
also provide ammonia reduction co-benefits. The State concludes that a 
30% reduction is a reasonable upper bound on the potential ammonia 
reductions to model. Finally, the State's precursor demonstration 
presents extensive support for the State's conclusion that there is an 
ambient excess of ammonia relative to nitrate, i.e., that particulate 
ammonium nitrate formation in SJV is NOX-limited, and will 
become increasingly NOX-limited as NOX reductions 
increase into the future from the State's motor vehicle control program 
and other measures the State intends to undertake in the Serious area 
plan. Based on the forgoing considerations, the State concludes that 
ammonia emissions do not contribute significantly to ambient 
PM2.5 levels that exceed the 2012 annual PM2.5 
NAAQS in the SJV.
    The EPA presented its initial evaluation of the State's ammonia 
precursor demonstration in section IV.B.3.a of the 2021 Proposed Rule, 
with more detailed summaries and evaluation in two EPA technical 
support documents (TSDs): ``Technical Support Document, EPA Evaluation 
of PM2.5 Precursor Demonstration, San Joaquin Valley 
PM2.5 Plan for the 2006 PM2.5 NAAQS,'' February 
2020 (``EPA's PM2.5 Precursor TSD''), and ``Technical 
Support Document, EPA Evaluation of Ammonia Precursor Demonstration, 
San Joaquin Valley Moderate Area PM2.5 Plan for the 2012 
PM2.5 NAAQS,'' August 2021 (``EPA's Ammonia Precursor 
TSD'').
    We noted that the EPA's PM2.5 Precursor Guidance 
provides for consideration of future year sensitivity and that 
consideration of additional information beyond the concentration-based 
and sensitivity-based analyses may be appropriate in assessing a 
precursor's significance. We summarized the State's assertions that 30% 
is a reasonable upper bound for potential ammonia emission reductions 
based on research cited in Appendix C of the 2018 PM2.5 Plan 
concerning ammonia emissions and potential control options for 
agricultural sources.\46\ However, we did not elaborate in the 2021 
Proposed Rule as to why we proposed to agree that 30% was a reasonable 
upper bound.
---------------------------------------------------------------------------

    \46\ EPA's PM2.5 Precursor TSD, 13.
---------------------------------------------------------------------------

    We stated that ambient PM2.5 responses to ammonia 
emission reductions decline over time, and in concert with the large 
projected NOX emission reductions, with the largest declines 
occurring at sites with highest projected PM2.5 levels. For 
the two sites (Madera and Hanford) where the State's modeled response 
in 2024 to a 30% ammonia emission reduction exceeded the recommended 
0.2 [micro]g/m\3\ threshold, we evaluated additional information and, 
based on that information, gave the modeled projected responses above 
the threshold at these sites less weight.
    We also considered studies cited by CARB on the 2013 DISCOVER-AQ 
aircraft measurements and 2017 satellite measurements, both of which 
suggest that ammonia concentrations are underestimated in the SJV. We 
noted that if modeled ammonia concentrations were closer to 
observations, then the modeled response to ammonia precursor reductions 
would be lower than shown in the 2018 PM2.5 Plan's precursor 
demonstration. Similarly, an increase in modeled ambient ammonia 
concentrations would also make the model response more consistent with 
the evidence from the multiple ambient measurement studies that suggest 
a very low ambient sensitivity to ammonia, based on measured excess 
ammonia relative to NOX, the abundance of particulate 
nitrate relative to gaseous NOX, and the large abundance of 
ammonia relative to nitric acid. These ambient measurement studies all 
conclude that there is a large amount of ammonia left over after 
reacting with NOX, so that ammonia emission reductions would 
be expected mainly to reduce the amount of ammonia excess, rather than 
to reduce the particulate ammonium nitrate, and thus provided strong 
evidence independent of the modeling that ambient PM2.5 
levels would respond comparatively weakly to ammonia emissions 
reductions.
    Regarding changes in the effect of ammonia emission reductions over 
time as other pollutant levels change, we stated it was appropriate to 
consider changes in atmospheric chemistry that may occur between the 
base or current year and the attainment year because the changes may 
ultimately affect the nonattainment area's progress toward expeditious 
attainment. We stated that the 2024 model results would in this case 
better represent the point in time at which it is appropriate to 
evaluate what potential ammonia controls could achieve, because of the 
steep decline in NOX emissions the State projects will occur 
by 2024 and 2025 as a result of existing or intended control measures. 
We also noted that the projected annual average PM2.5 
concentration of 12.0 [micro]g/m\3\, occurring at the Bakersfield-Planz 
monitoring site in 2025, would be reduced by 0.12 [micro]g/m\3\, which 
would not be considered significant (it is below the EPA's recommended 
threshold of 0.2 [micro]g/m\3\).
    In sum, we concluded that the State had evaluated the sensitivity 
of ambient PM2.5 levels to potential reductions in ammonia 
emissions using appropriate modeling techniques; the modeled response 
to ammonia reductions is likely lower than reported; and the State's 
choice of 2024 and 2025 as the reference points for purposes of 
evaluating the sensitivity of ambient PM2.5 levels to 
ammonia emission reductions was well-supported. Based on all of these 
considerations, the EPA previously proposed to approve the State's 
demonstration that ammonia emissions do not contribute significantly to 
ambient PM2.5 levels that exceed the 2012 annual 
PM2.5 NAAQS in the SJV.
2. Summary of Adverse Comments
    Public Justice states that the ``EPA must disapprove the ammonia 
precursor demonstration'' and that ``CARB's tortured analysis (and 
EPA's proposed acceptance of it)'' is arbitrary and capricious. The 
commenter makes several assertions in support of this comment.\47\
---------------------------------------------------------------------------

    \47\ Public Justice Comment Letter, 16-18.
---------------------------------------------------------------------------

    First, Public Justice notes that CARB's analysis concluded that 
ammonia contributes 5.2 [micro]g/m\3\ to annual average 
PM2.5 concentrations, and that this is well above the EPA's 
recommended annual average contribution threshold of 0.2 [micro]g/
m\3\.\48\ The commenters also

[[Page 60500]]

took issue with CARB and the EPA's arguments that such results 
overstate the role of ammonia because NOX emissions decline 
over time, and the EPA's decision to look at the results of sensitivity 
modeling for the response of ambient PM2.5 levels to 
potential ammonia emission reductions in the future year 2024. The 
commenters assert that this analytical approach of considering the 
projected sensitivity to ammonia reductions in the future year 
``ignores the statutory imperative to demonstrate attainment as 
expeditiously as practicable,'' per CAA section 172(a)(2)(A), and that, 
even after evaluating the impact ``for the most favorable date'' 
(2024), CARB still found significant contribution for ammonia above the 
EPA's recommended threshold.
---------------------------------------------------------------------------

    \48\ The commenters note that 38% of the annual average ambient 
PM2.5 in Bakersfield is ammonium nitrate. Public Justice 
Comment Letter, 6. See also, 2018 PM2.5 Plan, Ch. 3, 
Figure 3-2 (``Bakersfield PM2.5 Speciation (Average 2011 
to 2013)'').
---------------------------------------------------------------------------

    Second, Public Justice questioned CARB's reliance and the EPA's 
proposed acceptance of a sensitivity analysis that assumed only a 30% 
modeled reduction of ammonia emissions. Public Justice points out that 
the EPA's guidance for precursor demonstrations suggests that states 
should evaluate the effect of reducing emissions between 30% and 70%, 
and states that ``CARB argues, and EPA agrees, that only the minimal 30 
percent control level is reasonable'' despite large ammonia sources 
(e.g., ``industrial dairy and poultry operations'') never having been 
regulated in the SJV and the prospect for relatively easier and cheaper 
emission reductions than those for NOX.\49\ The commenters 
argue that ``[t]he analysis of potential controls is particular[ly] 
weak and ignores the wealth of literature demonstrating that strategies 
for reducing ammonia emissions from agriculture . . . are among the 
most effective for reducing PM concentrations,'' and cite several 
studies in support of this argument. The commenters further state that 
reducing ammonia emissions may be achieved through ``strategies such as 
improving livestock feed to reduce excreted nutrients, altering manure 
storage and handling practices to prevent [ammonia] emissions, and 
improving synthetic fertilizer use efficiency,'' again citing numerous 
studies.\50\ The commenters state that agriculture is responsible for 
over 80% of ammonia emissions, and that confined animal facilities 
(CAFs) and fertilizer application account for 57% and 36%, 
respectively.\51\ Moreover, the commenters assert that ``[n]o real 
analysis of control potential is offered'' in the State's precursor 
demonstration.
---------------------------------------------------------------------------

    \49\ Public Justice Comment Letter, 2, 5, and 16-17, and 
Exhibits 31 through 34.
    \50\ Public Justice Comment Letter, 16-17, Exhibits 35 through 
40 and three additional studies: N. Cole, et al., ``Influence of 
dietary crude protein concentration and source on potential ammonia 
emissions from beef cattle manure,'' J. Anim. Sci. 83, 722, 2005; N. 
Cole, P. Defoor, M. Galyean, G. Duff, J. Gleghorn, ``Effects of 
phase-feeding of crude protein on performance, carcass 
characteristics, serum urea nitrogen concentrations, and manure 
nitrogen of finishing beef steers,'' J. Anim. Sci. 12, 3421-3432, 
2006; and R. Todd, N. Cole, R. Clark, ``Reducing crude protein in 
beef cattle diet reduces ammonia emissions from artificial feedyard 
surfaces,'' J. Environ. Qual. 35, 404-411, 2006.
    \51\ Public Justice Comment Letter, 5-6, 16, citing See EPA 
Region IX, ``Technical Support Document, EPA Evaluation of 
PM2.5 Precursor Demonstration, San Joaquin Valley 
PM2.5 Plan for the 2006 PM2.5 NAAQS.'' We note 
that our TSD in turn cited to State data sources, including the 2018 
PM2.5 Plan, App. G, Figure 3.
---------------------------------------------------------------------------

    Third, with respect to the State and the EPA's evaluation of 
modeled ambient PM2.5 responses to ammonia emission 
reductions in 2024, Public Justice states that, in the low (30%) 
emission scenario, 2 of 15 monitoring sites have responses over the 0.2 
[micro]g/m\3\ recommended threshold and that the EPA argues ``with 
extremely biased evidence, that the results at one of the two monitors 
could be ignored and that ammonia emissions area likely 
underestimated.'' The commenters assert that ``EPA points to evidence 
that `the State did not discuss' to discount the results'' for the 
Madera monitor, and that the EPA ``offers no excuse for discrediting 
the results at the other monitor.''
    Fourth, the commenters claim that the EPA's evaluation of the 
precursor demonstration looked at supplemental ammonia emission studies 
but ignored supplemental studies showing that NOX emissions 
from soil (``soil NOX'') may be significantly 
underestimated. Public Justice states that the State and the EPA 
``assert that NOX emissions will be significantly reduced by 
2024 even though the Plan currently does not explain how those 
NOX reductions will occur.'' The commenters state that such 
approach is ``a one-sided attempt to explain away modeled results that 
ammonia contributes significantly to PM2.5'' in the SJV and 
cannot overcome the Act's presumption that precursors must be 
controlled.
    Finally, beyond the assertion that the State's precursor 
demonstration with respect to ammonia, and the EPA's proposed approval 
of it are incorrect, the commenters also argue that the State's failure 
to address ammonia as a precursor to PM2.5 has disparate 
impacts on certain communities within SJV and ``avoids difficult 
political fights by sacrificing communities of color.'' Finally, the 
commenters refer to a 2021 research study that estimates that 1,690 
people in California die annually due to agricultural ammonia 
emissions.\52\
---------------------------------------------------------------------------

    \52\ Public Justice Comment Letter, 18. See Domingo, N.G.G., 
Balasubramanian, S., Thakrar, S.K., Clark, M.A., Adams, P.J., 
Marshall, J.D., Muller, N.Z., Pandis, S.N., Polasky, S., Robinson, 
A.L., Tessum, C.W., Tilman, D., Tschofen, P., & Hill, J.D., ``Air 
quality-related health damages of food,'' Proceedings of the 
National Academy of Sciences (Vol. 118, Issue 20, p. e2013637118), 
2021, available at https://doi.org/10.1073/pnas.2013637118, attached 
as Exhibit 35. See Supplementary Information for ``Air quality-
related health damages of food,'' Table S2 (``Annual emissions and 
mortality caused by agricultural production in the 10 states where 
emissions of (A) primary PM2.5, (B) NH3, (C) 
NOX, (D) SO2, and (E) NMVOCs lead to the 
highest total mortality'').
---------------------------------------------------------------------------

3. The EPA's Reconsidered Proposal
    The EPA agrees with certain points made by the commenters with 
respect to ammonia and disagrees with others. Overall, based on the 
adverse comments from Public Justice and a re-evaluation of the 
information provided by the State, we now conclude that the weight of 
evidence is insufficient to establish that ammonia does not contribute 
significantly to PM2.5 levels above the NAAQS in the SJV. 
The EPA's further evaluation indicates that it is appropriate to retain 
the statutory presumption that ammonia must be regulated as a precursor 
for the 2012 annual PM2.5 NAAQS in the SJV. Accordingly, if 
the EPA finalizes disapproval of the State's ammonia precursor 
demonstration, ammonia would remain a plan precursor, and the SJV would 
remain subject to the requirements to identify and implement BACM, 
BACT, and additional feasible measures on sources of ammonia emissions.
    We first address the portion of the comment related to the 
sensitivity of the modeled PM2.5 response to reductions in 
ammonia emissions and then turn to the portion of the comment 
addressing the amount of ammonia reductions that may be available.
a. Comments Related to Sensitivity Modeling Results
    The measured ammonium nitrate portion of the annual average 
PM2.5 concentration in Bakersfield in 2015 was 5.2 [micro]g/
m\3\.\53\ This is well above the EPA's recommended threshold in the 
PM2.5 Precursor Guidance. However, the PM2.5 SIP 
Requirements Rule, as interpreted by that guidance, provides the option 
for a State to conduct an analysis of the sensitivity of ambient 
PM2.5 concentrations to emission reductions of a precursor 
pollutant to evaluate the significance of that precursor,\54\ as the 
State did for the 2012

[[Page 60501]]

annual PM2.5 NAAQS in the SJV. Thus, the concentration-based 
contribution analysis alone (i.e., the 5.2 [micro]g/m\3\) is not 
necessarily determinative of a precursor's significance.
---------------------------------------------------------------------------

    \53\ 86 FR 74310, 74318 and 2018 PM2.5 Plan, App. G, 
3.
    \54\ 40 CFR 51.1006(a)(1)(ii).
---------------------------------------------------------------------------

    The commenters stated that reliance on a sensitivity-based test for 
2024 ignores the statutory imperative for expeditious attainment. But, 
as noted in the preamble for the PM2.5 SIP Requirements Rule 
in explaining the rationale for a sensitivity-based test, ``if 
conditions in a particular area are such that control of sources of one 
or more precursors does not reduce PM2.5 concentrations in 
the area, then those controls will not help the area attain 
(expeditiously or otherwise).'' \55\ Thus, if a precursor demonstration 
were to show that control of a particular precursor is not effective 
for reaching attainment, then the absence of such control would not 
violate the requirement for expeditious attainment.
---------------------------------------------------------------------------

    \55\ 81 FR 58010, 58025.
---------------------------------------------------------------------------

    As commenters noted, the State relied on its sensitivity-based 
contribution analysis for a future year (2024) to evaluate the 
significance of ammonia as a precursor to ambient PM2.5 
concentrations in the San Joaquin Valley. In our 2021 Proposed Rule, we 
discussed the State's selection of 2024 as an acceptable analysis year, 
given the projected steep decline in ambient PM2.5 
sensitivity to ammonia reductions over time as a result of projected 
changes in emissions (i.e., large NOX emission reductions as 
contemplated in the Plan, through existing measures and aggregate 
commitments), consistent with the facts and circumstances recommended 
for consideration in the EPA's PM2.5 Precursor Guidance.\56\
---------------------------------------------------------------------------

    \56\ 86 FR 74310, 74320-74321 and PM2.5 Precursor 
Guidance, 35.
---------------------------------------------------------------------------

    The PM2.5 Precursor Guidance provides for consideration 
of sensitivity in an appropriate future year.\57\ Based on the State's 
control strategy, including baseline emission reduction measures and 
its control measure and aggregate tonnage commitments, the State 
estimated it would achieve over 200 tpd NOX reductions by 
2024, representing over 60% of the 2013 base year emissions inventory 
for NOX.\58\ Existing baseline measures already in the SIP 
are projected by the State to reduce annual average NOX 
emissions in the SJV by 173.5 tpd, which is 83.7% of the 207.38 tpd of 
NOX reductions modeled to attain the 2012 annual 
PM2.5 NAAQS. Over 90% of the baseline NOX 
reductions between 2013 and 2025 are due to the existing mobile source 
control program.\59\ These reductions will occur regardless of any EPA 
action on the precursor demonstration or the 2018 PM2.5 Plan 
as a whole. Similarly, additional measures adopted by the State through 
the end of 2021 further reduce NOX emissions. Given the 
large NOX emission reductions projected to occur by 2024 and 
2025, the EPA has concluded that that the 2024 sensitivity model 
results better represent the atmospheric chemistry around the 
attainment date and in subsequent years than sensitivity modeling 
results from 2013 and even 2020.\60\ Due to continued existing and 
anticipated NOX reductions, the apparent PM2.5 
benefit of ammonia reductions in earlier years declines with time and 
does not reflect the ultimate, lower, benefit of such controls near the 
attainment year and later.
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    \57\ PM2.5 Precursor Guidance, 35.
    \58\ 86 FR 74310, 74327, Table 4.
    \59\ 2018 PM2.5 Plan, App. B, Table B-2.
    \60\ We address the potential impact of ammonia emissions on the 
requirement for expeditious attainment in our re-evaluation of the 
attainment demonstration in section II.C.3, below.
---------------------------------------------------------------------------

    Thus, the EPA reasons that the Plan's baseline and additional 
control measures will change (and have already changed) the atmospheric 
chemistry conditions in the SJV, leading to ambient PM2.5 
formation that is much less sensitive to ammonia emission reductions in 
the attainment year. We maintain that the State's reliance on its 
sensitivity-based contribution analysis for 2024 to evaluate the 
significance of ammonia as a precursor is reasonable, well supported, 
and consistent with the PM2.5 SIP Requirements Rule and EPA 
guidance.
    The commenter correctly states that 2 of 15 sites in the 2024 model 
scenario based on a 30% reduction in ammonia emission were modeled to 
have an ambient PM2.5 response greater than the EPA's 
recommended contribution threshold of 0.2 [micro]g/m\3\. However, we 
disagree with the commenter's characterization that our further review 
of the sensitivity of the Madera and Hanford sites to ammonia emission 
reductions was argued ``with extremely biased evidence.'' \61\
---------------------------------------------------------------------------

    \61\ Public Justice Comment Letter, 18.
---------------------------------------------------------------------------

    For the Madera monitor (estimated sensitivity of 0.21 [micro]g/m\3\ 
in 2024 to a 30% ammonia emission reduction), the commenter refers to 
the EPA's statement that the 2018 PM2.5 Plan did not discuss 
the evidence for the 2013 monitored concentrations at this site being 
biased high (as a matter of the physical recordings of the monitor). 
However, the EPA did reference the State's prior analysis of such 
evidence, which we considered in our evaluation.\62\ Aside from 
pointing out that this analysis was not included in the Plan itself, 
the comment does not offer analysis to the contrary, and the EPA 
continues to think that we reasonably weighed the technical information 
before us and, given the role of the 2013 monitored data in the 
sensitivity modeling conducted by the State, correctly concluded that 
``if more typical Madera concentrations were used, it is likely that 
the 2024 Madera response to ammonia reductions would be below the 
contribution threshold'' and that the extra year of NOX 
reductions from 2024 to 2025 would likely decrease the sensitivity 
below the recommended 0.2 [micro]g/m\3\ threshold.
---------------------------------------------------------------------------

    \62\ 86 FR 74310, 74320, fn. 91, and fn. 92. This analysis 
concluded that 2011-2013 Madera data did not fit the geographic 
pattern historically seen in relation to other monitors but returned 
to the historic pattern after corrections were made to the 
monitoring instrument operating procedures. Concentrations were 
estimated to be about 10% high during the period in question.
---------------------------------------------------------------------------

    We further disagree with the commenter's assertion that we offered 
no reason for giving less weight to modeled sensitivity results for the 
Hanford monitor (estimated sensitivity of 0.26 [micro]g/m\3\ in 2024 to 
a 30% ammonia emission reduction). We stated that we gave both Madera 
and Hanford modeled sensitivity lower weight in our overall assessment 
of ammonia as a precursor. Specifically for Hanford, we described 
evidence that the modeled sensitivity there was likely overestimated. 
That evidence included an independent study using data from the 2013 
DISCOVER-AQ campaign that ``found that the [CMAQ] model underestimated 
ammonia at Hanford by a roughly a factor of four or five.'' \63\ In our 
assessment, if the model's ammonia concentrations better matched the 
observations then there would be more of an ammonia excess in the 
model, and the modeled response to ammonia reductions would be lower.
---------------------------------------------------------------------------

    \63\ 86 FR 74310, 74320.
---------------------------------------------------------------------------

    More broadly, prior to publishing the 2021 Proposed Rule, the EPA 
reviewed available research including from supplemental materials from 
CARB, and found a consistent theme based on modeling analyses and 
ambient measurement studies--that ``there is a large amount of ammonia 
left over after reacting with NOX, so that ammonia emission 
reductions would be expected mainly to reduce the amount of ammonia 
excess, rather than to reduce the particulate ammonium nitrate.'' \64\ 
It is important to note that this ammonia excess is measured, and is 
independent

[[Page 60502]]

of any assumptions about the size of the ammonia or NOX 
emissions inventories, and also independent of any uncertainties in the 
modeling exercise. The concerns raised by Public Justice about relative 
levels of ammonia and NOX estimation are not sufficient to 
cause the EPA to revise the conclusion that PM2.5 is likely 
to have low sensitivity to ammonia reductions, which is supported by 
the actual observed conditions. The ambient measurement evidence is 
strong and leads the EPA to believe that the modeled response to 
ammonia in the State's precursor demonstration may be overestimated. 
Therefore, we maintain that the EPA may give lower weight to the 
modeled sensitivities of ambient PM2.5 concentrations to 
ammonia emission reductions at the Madera and Hanford sites.
---------------------------------------------------------------------------

    \64\ Id. See also, EPA's Ammonia Precursor TSD.
---------------------------------------------------------------------------

    The commenter states that the EPA's argument on the relative levels 
of ammonia and NOX emissions looks at such ammonia studies 
but ``ignores supplemental studies showing that . . . soil 
NOX emissions [may be significantly underestimated].'' \65\ 
Unlike the general consensus in the ammonia studies described above, 
with respect to the amount of NOX emitted by soil in the SJV 
the EPA believes that there is conflicting research. A conclusion of 
Almaraz et al. (2018) and Sha et al. (2021) cited by the commenters is 
that soil NOX emissions are underestimated, and that they 
comprise 30-40% of total NOX emission in California. While 
higher levels of soil NOX (or NOX more generally) 
would tend to increase the modeled sensitivity of ambient 
PM2.5 to ammonia, we maintain that there is not a sufficient 
basis to conclude that higher soil NOX emissions should be 
used in the air quality modeling for the SJV.\66\
---------------------------------------------------------------------------

    \65\ Public Justice Comment Letter, 18. Public Justice cited 
Almaraz et al. (2018), ``Agriculture is a major source of 
NOX pollution in California,'' Science Advances, 4(1), 
doi:10.1126/sciadv.aao3477, 2018, available at https://advances.sciencemag.org/content/4/1/eaao3477; and Sha et al. (2021), 
``Impacts of soil NOX emission on O3 air 
quality in rural California,'' Environmental Science & Technology, 
55(10), 7113-7122, available at: doi:10.1021/acs.est.0c06834; 
available at https://pubs.acs.org/doi/10.1021/acs.est.0c06834.
    \66\ See also, EPA Region IX, ``Response to Comments Document 
for the EPA's Final Action on the San Joaquin Valley Serious Area 
Plan for the 2006 PM2.5 NAAQS,'' June 2020, 148 and 158.
---------------------------------------------------------------------------

    In contrast to the studies just cited, Guo et al. (2020) \67\ did 
not find such a discrepancy in emissions estimates, concluding that 
soil NOX is about 1% of anthropogenic NOX 
emissions. The fraction of nitrogen applied as fertilizer released as 
NOX to the atmosphere was estimated by Almaraz et al. to be 
15%, while seven other studies reviewed by Guo et al. estimated it to 
be 2% or less. Yet Almaraz et al., Sha et al., and Guo et al. all 
reported high agreement between their modeled and observed soil 
NOX emissions. The Almaraz et al. study acknowledged the 
limited number of surface measurements that were available for purposes 
of comparing the model results and the difficulty in comparing the 
model results to the observations and noted the need for more field 
measurements. Guo et al. stated that obtaining an emission factor 
correlating NOX emissions to fertilizer application from the 
data available in various studies (including Almaraz et al.) would be 
``difficult or impossible'' due to the sparsity of data collected in 
terms of sampling length, sampling frequency, and the episodic nature 
of nitrogen gas emissions from soil.
---------------------------------------------------------------------------

    \67\ Guo et al. (2020), ``Assessment of Nitrogen Oxide Emissions 
and San Joaquin Valley PM2.5 Impacts From Soils in 
California,'' Journal of Geophysical Research: Atmospheres, 125(24), 
doi: 10.1029/2020JD033304; available at https://doi.org/10.1029/2020JD033304.
---------------------------------------------------------------------------

    In light of the uncertainties and disagreements among studies, the 
EPA does not believe that available research provides sufficient 
certainty about the magnitude and proportion of soil NOX 
emissions attributable to agricultural fertilizer application to 
require substantial revisions in the NOX emissions inventory 
nor the PM2.5 modeling at this time.
    In addition, as just described, multiple studies of ambient 
measurements show excess ammonia in the atmosphere, which is strong 
evidence of low sensitivity to ammonia reduction that is independent of 
the accuracy of estimates of precursor emissions from any source, 
including soil NOX, and independent of any modeling. Thus, 
we disagree that the EPA ``ignored'' the supplemental soil 
NOX studies; we were aware of and considered them, but they 
did not change our conclusion.
b. Comments Related to Scale of Potential Ammonia Emission Reductions
    The 2018 PM2.5 Plan includes modeling of 30% and 70% 
reductions in ammonia emissions and focuses on the results of the 30% 
reduction based on the assertion that the area could not achieve more 
than a 30% decrease in ammonia emissions. Public Justice questions the 
basis for the assertion that no more than 30% reductions are available. 
In this section, we examine, based on the submission, the 
PM2.5 Precursor Guidance, and the Public Justice comment, 
the ammonia reductions that may be available in the SJV. Specifically, 
we explore the uncertainty with respect to both the current state of 
ammonia emissions and controls in the SJV and available research 
examining additional control options that may be available. We conclude 
that, based on the information before us, the 2018 PM2.5 
Plan does not provide sufficient support for the assertion that 30% is 
a reasonable upper bound on available ammonia reductions in the SJV.
    The District presented its analysis of ammonia control for the 
primary ammonia source categories in the SJV in Appendix C, section 
C.25 (``Ammonia in the San Joaquin Valley'') of the 2018 
PM2.5 Plan. The EPA had reviewed this analysis for our 
assessment in the 2021 Proposed Rule that 30% was, for analytical 
purposes, a reasonable upper bound for ammonia emission reductions in 
the SJV, and referred to prior EPA analysis for our action on the 2006 
24-hour PM2.5 NAAQS portion of the 2018 PM2.5 
Plan.\68\ In evaluating the Public Justice comments on the potential 
control of ammonia, however, we have re-evaluated other portions of the 
2018 PM2.5 Plan, including Appendix C, section C.25 and 
Appendix G,\69\ and reviewed the studies cited by the commenters, as 
well as others from the EPA's own literature search.
---------------------------------------------------------------------------

    \68\ 86 FR 74310, 74319. See also, 85 FR 17382, 17395 (March 27, 
2020), and EPA's PM2.5 Precursor TSD, 13.
    \69\ See, e.g., 2018 PM2.5 Plan, App. G, 13, where 
CARB states that ``CARB staff, District staff, and the public 
process have not identified specific controls that are 
technologically and economically feasible to achieve reductions at 
the low end of the recommended sensitivity range (i.e., 30 percent), 
much less at the upper end of the range.''
---------------------------------------------------------------------------

    As noted in the EPA's PM2.5 Precursor Guidance,\70\ and 
consistent with the PM2.5 SIP Requirements Rule (40 CFR 
51.1010(a)(2)(ii), 51.1006(a)(1)(ii)), the EPA may require the State to 
identify and evaluate potential control measures for a precursor to 
determine the potential emissions reductions achievable, as a part of 
the precursor analysis. The guidance states that this evaluation is 
particularly important when the PM2.5 response to a 30% 
reduction in precursor emissions is close to the contribution 
threshold. In the case of a nonattainment area classified as Serious, 
this analysis would include identification and evaluation of measures 
that would constitute BACM/BACT level controls for such pollutant.\71\
---------------------------------------------------------------------------

    \70\ PM2.5 Precursor Guidance, 31.
    \71\ The PM2.5 Precursor Guidance provides: 
``[c]onsistent with the PM2.5 SIP Requirements Rule, the 
EPA may in some cases require air agencies to evaluate available 
emissions controls in support of a precursor demonstration that 
relies on a sensitivity analysis. [See 40 CFR 51.1009(a)(2) and 
51.1010(a)(2).] It is particularly important for states to evaluate 
available controls where the recommended contribution threshold--
that is, the threshold used for identifying an impact that is 
`insignificant'--is close to being exceeded at the low end of the 
recommended sensitivity range (e.g., 30 percent). In these cases, 
the EPA may determine that to sufficiently evaluate whether the area 
is sensitive to reductions, the State must determine the potential 
precursor emission reductions achievable through the implementation 
of available and reasonable controls for a Moderate area (or best 
controls for a Serious area).'' PM2.5 Precursor Guidance 
at 31.

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

[[Page 60503]]

    Even when the modeled responses are below the recommended 0.2 
[micro]g/m\3\ contribution threshold, or when particular responses are 
given less weight as we have discussed above for Madera and Hanford, 
the outcome of a sufficiently thorough controls evaluation and its 
conclusions on achievable emissions reductions may be important 
information for the EPA to consider in deciding whether to approve the 
precursor demonstration. Here, the State's ammonia precursor 
demonstration strongly relies on the assertion that no more than 30% 
ammonia reductions below current levels is achievable, but there is not 
a sufficiently thorough controls evaluation to support that assertion. 
Because the 30% value has not been adequately supported, the EPA cannot 
evaluate whether the modeled PM2.5 reductions associated 
with a 30% reduction in ammonia represent the reductions that may be 
possible in the SJV.
    The EPA also emphasizes that the 30% control threshold is part of 
an analytical test to help evaluate whether the State must regulate 
ammonia as a precursor for the 2012 annual PM2.5 NAAQS in 
the area; it does not mean that if the State cannot control 30% of 
ammonia with BACM/BACT-level controls that there is per se no need to 
regulate ammonia. For example, if control of 25% of ammonia is 
necessary for attainment of the PM2.5 NAAQS, then the fact 
that this is below 30% is irrelevant. Our attention to the 30% 
threshold in this notice is to help interpret the PM2.5 
responses to modeled ammonia emissions reductions in the State's 
precursor demonstration, which modeled a 30% reduction. This point is 
important analytically because, insofar as potential ammonia reductions 
could be larger than 30%, the modeled responses could be larger than 
those relied upon in the State's precursor analysis to support its 
determination that ammonia is not a significant precursor.
    With respect to the State's assertion that 30% is a reasonable 
upper bound for potential ammonia emission reductions, we agree with 
the commenters that the analysis of potential ammonia controls provided 
by the State and the evaluation of that information by the EPA lacked 
detailed support and is not a sufficient basis for the EPA to affirm 
that 30% is a reasonable upper bound for potential ammonia emission 
reduction in the SJV. This, in turn, affects the EPA's interpretation 
of the results of modeled responses to ammonia reductions. There are 
two general deficiencies in the submitted analysis that create 
uncertainty as to the potential for ammonia emission reductions, as 
discussed below: (1) incomplete quantification of existing ammonia 
emission reductions from the largest sources of ammonia; and 2) 
incomplete consideration and evaluation of potential additional 
controls of ammonia emissions for sources in the SJV. We walk through 
these uncertainties for each of the largest sources of ammonia in the 
SJV (i.e., CAFs and fertilizer application).
    As an initial matter, the commenters state that ``[the State] 
argues, and EPA agrees, that only the minimal 30 percent control level 
is reasonable'' despite major ammonia sources never having been 
regulated in the SJV and the relatively easier and cheaper sources of 
emission reductions relative to NOX. We understand this 
reference to ``major ammonia sources'' to mean the main source 
categories of ammonia emissions in the SJV, including CAFs and 
fertilizer application, which the State estimated to emit 57% and 36%, 
respectively, of the annual average ammonia emissions in the SJV in 
2013.\72\
---------------------------------------------------------------------------

    \72\ See Public Justice Comment Letter, 6, citing EPA Region IX, 
``Technical Support Document, EPA Evaluation of PM2.5 
Precursor Demonstration, San Joaquin Valley PM2.5 Plan 
for the 2006 PM2.5 NAAQS.''
---------------------------------------------------------------------------

    We agree with the commenters that neither CARB nor the District 
have imposed controls specifically to regulate ammonia. We note, 
however, that ammonia-specific controls are not required for approval 
of an ammonia precursor demonstration. Moreover, although there are not 
ammonia-specific controls in place for the largest source categories in 
the SJV, many sources of ammonia are in fact regulated by District 
rules, such as Rule 4570 (``Confined Animal Facilities''), Rule 4565 
(``Biosolids, Animal Manure, and Poultry Litter Operations''), and Rule 
4566 (``Organic Material Composting Operations''), which include 
enforceable requirements for VOC emissions that would, in general, 
achieve some degree of ammonia emission reductions. We agree with the 
general assertion, presented by the District in section C-25 (``Ammonia 
in the San Joaquin Valley'') of Appendix C of the 2018 PM2.5 
Plan, that some management practices to reduce VOCs in those rules also 
collaterally reduce ammonia emissions by limiting ammonia formation and 
volatilization, even though ammonia reductions are not legally required 
by these measures.\73\
---------------------------------------------------------------------------

    \73\ See, e.g., 2018 PM2.5 Plan, App. C, C-313 (for 
CAFs). The lack of controls specifically regulating ammonia 
emissions from the largest source categories through enforceable SIP 
requirements in the SJV is not an inherent deficiency of the 
precursor demonstration, but it does result in challenges for 
determining the potential for ammonia emission controls (i.e., in 
determining the reductions that have already been achieved, and what 
additional reductions are available).
---------------------------------------------------------------------------

    Although we expect that existing VOC regulations are achieving a 
degree of ammonia control, there are multiple reasons why it is not 
clear, based on the record before us, how much reduction is being 
achieved, and thus how much additional reduction may be available. For 
example, regarding CAFs, as the EPA has previously noted,\74\ the State 
has not sufficiently substantiated its calculation of 100 tpd of 
ammonia emission reductions attributed to Rule 4570. In the 2018 
PM2.5 Plan, the State referenced an outdated analysis from 
2006 that relied on a different baseline emissions inventory, but has 
not supplemented this analysis, or reconciled it with more recent 
emissions inventory data.\75\ We note that CARB has provided the EPA 
with significantly lower estimates of ammonia emission reductions 
achieved by SJVUAPCD Rule 4570 based on more recent calculations of 
reductions from a 2012 baseline emissions inventory.\76\ The 2018 
PM2.5 Plan does not reconcile these differences, nor update 
the emission reduction estimate from the 2006-era analysis to the 
emissions inventory basis of the 2018 PM2.5 Plan.
---------------------------------------------------------------------------

    \74\ 81 FR 69396, 69397-69398 (October 6, 2016).
    \75\ 2018 PM2.5 Plan, App. C, C-311 to C-339 and 
SJVUAPCD, ``Final Draft Staff Report, Proposed Re-Adoption of Rule 
4570 (Confined Animal Facilities),'' June 18, 2009, at Appendix F, 
``Ammonia Reductions Analysis for Proposed Rule 4570 (Confined 
Animal Facilities),'' June 15, 2006 (discussing various assumptions 
underlying the District's calculation of ammonia emission factors 
without identifying relevant emissions inventories).
    \76\ Email dated September 3, 2015, from Gabe Ruiz, CARB, to 
Larry Biland and Andrew Steckel, EPA Region IX, regarding ``SJV 
Livestock Ammonia Emissions with and without Rule 4570.'' This email 
notes that 2011 ammonia emissions (pre-rule) were 316.8 tpd, 2012 
emissions (without rule) were 323.8 tpd, and 2012 emissions (with 
rule) were 250.9 tpd. Thus, application of Rule 4570 would have 
achieved either 72.9 tpd of ammonia reductions, measured within 2012 
with and without the rule, or 65.9 tpd, measured from the 2011 level 
(without rule) to the 2012 level (with rule).

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

[[Page 60504]]

    In short, although we agree that some existing VOC controls will 
also result in ammonia reductions, a more detailed analysis it required 
to determine both the effectiveness of existing controls, and the 
additional controls that may be available. In the following, the EPA 
notes various uncertainties concerning ammonia emissions and in the 
amount of reductions achieved by specific rules as a byproduct of the 
existing VOC control measures. For a number of key source categories, 
ammonia measures require additional analysis to evaluate their 
potential to achieve additional emissions reductions, in part based on 
research studies included as exhibits to the Public Justice Comment 
Letter.
    For CAFs, the District discusses in detail how Rule 4570 is 
structured (e.g., to address varying types of CAFs); the five main CAF 
operations/emission sources: feeding, housing (including distinctions 
for housing configurations), solid waste, liquid waste, and land 
application of manure; the control menu requirements for each of those 
five operations; and research papers that estimate ammonia emission 
reductions from some of the measures.\77\ However, the 2018 
PM2.5 Plan does not specify, even in an aggregated form, 
which control measures were selected by CAFs in their permits-to-
operate with the District for each of the five operations and the scale 
of those selections by CAF size, nor does it quantify the emission 
reductions from those selections and scales. Thus it is unclear what 
level of ammonia control is being achieved, and, importantly for the 
precursor demonstration, unclear what level of further ammonia control 
may be possible. This uncertainty is increased by several provisions in 
Rule 4570 that allow CAF owners/operators to implement ``alternative 
mitigation measures'' \78\ in lieu of the mitigation measures listed in 
the rule, without any requirement to ensure that such alternative 
mitigation measures achieve any particular level of ammonia emission 
reductions, or any ammonia reductions at all.\79\
---------------------------------------------------------------------------

    \77\ 2018 PM2.5 Plan, App. C, C-312 to C-323.
    \78\ ``Alternative Mitigation Measure'' is defined in SJVUAPCD 
Rule 4570 as ``a mitigation measure that is determined by the APCO, 
[CARB], and EPA to achieve reductions that are equal to or exceed 
the reductions that would be achieved by other mitigation measures 
listed in this rule that owners/operators could choose to comply 
with rule requirements.'' SJVUAPCD Rule 4570 (amended October 21, 
2010), section 3.4. Because SJVUAPCD Rule 4570 explicitly applies 
only to VOC emissions, the requirement for equivalent ``reductions'' 
in section 3.4 applies only to VOC emission reductions and does not 
apply to ammonia emission reductions.
    \79\ See, e.g., SJVUAPCD Rule 4570 (amended October 21, 2010) at 
section 5.6, Table 4.1.F.
---------------------------------------------------------------------------

    Furthermore, for certain requirements, the 2018 PM2.5 
Plan assumes that a less effective control measure may be implemented 
given that the more effective control measure may be more costly. For 
instance, the District describes some research studies that relate to 
one or more of the options, but it is not clear whether and how the 
requirements of each option align with the practices evaluated in each 
study. The District cites a 2005 University of California study that 
manure from lagoons, diluted with irrigation water, and applied via 
surface gravity irrigation systems (e.g., not applied with a drag hose 
or similar apparatus) commonly minimized ammonia losses from 
volatilization to the air to 10% or less.\80\ However, it is not clear 
how the requirements of option H.2.a (liquid manure treated in an 
aerobic or anaerobic lagoon) or option H.2.b (24-hour limit for liquid 
manure standing on fields) may correspond to the study, whether any 
particular level of lagoon treatment or dilution prior to application 
would be needed, nor whether a combination of the two would be required 
to minimize ammonia losses to air to that degree.
---------------------------------------------------------------------------

    \80\ University of California, Division of Agricultural and 
Natural Resources, Committee of Experts on Dairy Manure Management, 
``Managing Dairy Manure in the Central Valley of California,'' June 
2005.
---------------------------------------------------------------------------

    For option H.2.c, the District states that use of a drag hose or 
similar apparatus could significantly reduce ammonia emissions, but 
without specifying how much or pointing to any supporting document, and 
only qualitatively asserting a relatively higher cost for using such 
equipment, and its limitations when a crop is growing.\81\ The District 
states that ``[a]pplication of liquid or slurry manure with a drag hose 
or similar apparatus could result in significant [ammonia] reductions, 
but has higher costs compared to flood or furrow irrigation of liquid 
manure.'' \82\ However, higher cost does not necessarily translate to 
the measure being economically infeasible, and thus the option to use 
flood or furrow irrigation alone may not represent the most appropriate 
method or level of control of ammonia for the land application of 
liquid manure. As a result, the District has not demonstrated that 
additional reductions are not feasible.
---------------------------------------------------------------------------

    \81\ 2018 PM2.5 Plan, App. C, C-323, referring to a 
2008 report by Alberta Agriculture and Food (Canada). Albert 
Agriculture and Food, ``Ammonia Volatilization from Manure 
Application,'' February 2008 (``2008 Alberta Report''). That report 
estimates that injection into soil would reduce the average 
ammonium-nitrogen fraction loss (i.e., to air) to 0% compared to 
incorporation within one day from surface application (25%) or 
compared to surface application with no incorporation (66%). 2008 
Alberta Report, Table 2.
    \82\ 2018 PM2.5 Plan, App. C, C-322 to C-323.
---------------------------------------------------------------------------

    The District assumes that all dairies and other cattle facilities 
would select option H.2.b (24-hour limit for liquid manure standing on 
fields) and cites two studies that suggest substantial ammonia emission 
reductions from this limitation, assuming no ammonia emissions into the 
air after soil incorporation.\83\ Based on one study, dairy CAF 
operations in the SJV would have hypothetically already reduced ammonia 
emissions to the air from land application of liquid manure from 66% 
ammonium nitrogen to 25% ammonium nitrogen by implementing option H.2.b 
(a 41% absolute reduction, or 62% relative reduction). Uncertainty 
about the options that are being chosen and implemented by regulated 
entities gives rise to uncertainty in the ammonia emission reductions 
that are being achieved. The permits-to-operate submitted by each dairy 
CAF are required to indicate which option has been selected.\84\ 
Accordingly these permits, and associated compliance records, should 
contain information that would help to address this uncertainty. 
Furthermore, if injection via drag hose or similar apparatus (option 
H.2.c) is economically feasible, even if more expensive, implementation 
of such a measure could further reduce ammonia by 25% based on the same 
study, at least for a portion of the operating cycle (e.g., when crops 
are not growing). Lastly, a combination of measures (e.g., requiring 
that liquid manure be both treated in an anaerobic lagoon, aerobic 
lagoon, or digester, and that it be incorporated into the soil within 
24 hours) or adjustment to existing options (e.g., requiring 
incorporation of liquid manure within 6 hours, rather than 24 hours, 
and during cooler hours when ammonia volatilization is less) could 
hypothetically reduce ammonia emissions at these sources by more than 
30%.\85\
---------------------------------------------------------------------------

    \83\ 2018 PM2.5 Plan, App. C, C-323, referring to two 
studies: the 2008 Alberta Report, and Chadwick et al. ``Emissions of 
Ammonia, Nitrous Oxide and Methane from Cattle Manure Heaps: Effect 
of Compaction and Covering,'' Atmosphere Environment, 39: 787-799 
(2005); available at: http://www.sciencedirect.com/science/article/pii/S135223100400994X.
    \84\ Under District Rule 4570, section 5.1, owners/operators of 
CAFs subject to the rule must obtain a permit-to-operate for the 
facility, and that permit must include a facility emission 
mitigation plan, a facility emission inventory, and identify the 
mitigation measures selected for the facility.
    \85\ 2008 Alberta Report.
---------------------------------------------------------------------------

    In general, with respect to dairy CAFs, on a qualitative basis CAF 
operators have likely reduced ammonia emissions

[[Page 60505]]

to a degree consistent with the options selected. However, there is not 
a quantitative basis to specify the degree and potential for further 
reduction. For some of the options within the menu of mitigation 
measures for each type of CAF in Rule 4570, there are research studies 
to support the basis of existing ammonia emission reductions. The 
generalized assumptions used by the State could be evaluated by an 
analysis of the options selected by CAFs in permits-to-operate with the 
District. Further assessment of available compliance records and 
examination of combinations of measures or adjustments to existing 
measures could help quantify additional potential ammonia emission 
reductions.
    In addition, Public Justice cites several studies to support its 
assertion that reductions in agricultural ammonia emissions may be 
achieved through ``strategies such as improving livestock feed to 
reduce excreted nutrients, altering manure storage and handling 
practices to prevent [ammonia] emissions, and improving synthetic 
fertilizer use efficiency,'' and cites several studies to support this 
assertion.\86\ The EPA considers these approaches to warrant 
examination as potential means to reduce ammonia and believes that more 
information regarding their efficacy as control measures and their 
economic and technical feasibility is needed to determine the amount of 
the potential additional ammonia control in the SJV.
---------------------------------------------------------------------------

    \86\ Public Justice Comment Letter, 16-18.
---------------------------------------------------------------------------

    For livestock feed, studies in 2005 and 2006 cited by the commenter 
found that ``decreasing the crude protein concentration of beef cattle 
finishing diets based upon steam-flaked corn from 13 to 11.5 percent 
decreased ammonia emissions by 30 to 44 percent.'' \87\ A 2009 study 
cited by the commenter found that ``one feedyard feeding distillers 
grains averaged 149 grams of ammonia-N per head per day (NH3-N/head/
day) over nine months, compared with 82 g NH3-N/head/day at another 
feedyard feeding lower protein steam-flaked, corn-based diets.'' \88\ 
Nominally this would represent a 45% reduction in ammonia emissions 
from manure by going to a lower protein diet. However, the net ammonia 
emission reduction either from reducing crude protein levels in feed, 
or by providing a lower protein steam-flaked, corn-based diet rather 
than a distiller grain diet is unclear given the role of protein intake 
on the time for beef cattle to reach market weight or on milk 
production for dairy cattle.
---------------------------------------------------------------------------

    \87\ Public Justice Comment Letter, Exhibit 36, 9. Exhibit 36 
is: Preece, Sharon L.M. et al., ``Ammonia Emissions from Cattle 
Feeding Operations,'' Texas A&M AgriLife Extension Service, 
referring to Cole, N.A., R.N. Clark, R.W. Todd, C.R. Richardson, A. 
Gueye, L.W. Greene, and K. McBride, ``Influence of Dietary Crude 
Protein Concentration and Source on Potential Ammonia Emissions from 
Beef Cattle Manure,'' Journal of Animal Science 83:(3), 722 (2005); 
and Todd, R.W., N.A. Cole, and R.N. Clark, ``Reducing Crude Protein 
in Beef Cattle Diet Reduces Ammonia Emissions from Artificial 
Feedyard Surfaces.'' Journal of Environmental Quality. 35:(2), 404-
411 (2006).
    \88\ Public Justice Exhibit 36, 10, referring to a study by 
Todd, R.W., N.A. Cole, D.B. Parker, M. Rhoades, and K. Casey. 2009. 
``Effect of Feeding Distillers Grains on Dietary Crude Protein and 
Ammonia Emissions from Beef Cattle Feedyards.'' In Proceedings of 
the Texas Animal Manure Management Issues Conference, 83-90.
---------------------------------------------------------------------------

    For manure handling and storage practices, a 2011 inventory of 
mitigation methods by Price et al. identifies many mitigation methods 
for various kinds of CAFs, some of which may reduce ammonia emissions 
by 50-90%.\89\ For example, Method 44 (``Washing down dairy cow 
collecting yards'') involves areas where dairy cows are collected on a 
concrete yard prior to milking and, after each milking event, the urine 
and manure in the area are removed by pressure washing or by hosing and 
brushing, resulting in up to 90% ammonia emission reductions. Method 62 
(``Cover solid manure stores with sheeting'') involves covering solid 
manure heaps with plastic sheeting, resulting in ammonia emission 
reductions up to 90%.\90\ However, the authors note that, for both 
Method 44 and Method 62, reducing ammonia emission from the milking 
areas would increase the ammonium content of the slurry, potentially 
leading to higher ammonia emissions during storage and spreading, but 
by a lower amount than the initial reduction amount. Method 71 (``Use 
slurry injection application techniques'') involves shallow (5-10 cm 
depth) or deep (25 cm depth) injection of slurry into the soil, 
resulting in ammonia emission reductions of 70% to 90%, respectively.
---------------------------------------------------------------------------

    \89\ Public Justice Comment Letter, Exhibit 39. Exhibit 39 is: 
Price et al., ``An Inventory of Mitigation Methods and Guide to 
their Effects on Diffuse Water Pollution, Greenhouse Gas Emissions 
and Ammonia Emissions from Agriculture, User Guide,'' December 2011. 
For mitigation measures that may reduce ammonia emissions by 50-90%, 
for example, methods 43, 44, 47-51, 54-55, 62, 64, 70-71, and 73-74 
on pages 70-71, 74-78, 81-84, 93-94, 105-108, and 110-112 
respectively, achievable control efficiencies from these measures in 
the SJV would depend on an applicability and feasibility review.
    \90\ We note that District Rule 4570, Table 3.1, section F and 
Table 4.1, section F provide mitigation measure options for the 
storage of solid manure and separated solids from large dairy CAFs, 
including measures that involve covering dry manure piles and 
separated solids, respectively, outside of pens with a weatherproof 
covering from May through October. Thus, such mitigation measures, 
if selected, would not be required for the remaining four months of 
the year (June through September). Similar mitigation measure 
options in Rule 4570 for covering dry manure piles apply for beef 
feedlots, other cattle, swine, poultry, and other CAF types.
---------------------------------------------------------------------------

    Mitigation methods are also described for other kinds of CAFs, such 
as pig farms and chicken farms. For example, Method 48 (``Install air-
scrubbers or biotrickling filters to mechanically ventilated pig 
housing'') involves pig housing where specific technologies are used to 
capture up to 90% of the ammonia emissions into recirculation water 
that can then be used as a nitrogen-based fertilizer. Method 51 (``In-
house poultry manure drying'') involves installation of ventilation/
drying systems that reduce the moisture content of poultry litter, 
resulting in up to 50% ammonia emission reductions, though, as with the 
cattle examples, this could result in some increased emissions at 
subsequent steps (e.g., storing poultry litter).
    In addition to the 2011 inventory of mitigation methods, in 
September 2017, the EPA and the U.S. Department of Agriculture, Natural 
Resource Conservation Service released the ``Agricultural Air Quality 
Conservation Measures, Reference Guide for Poultry and Livestock 
Production Systems'' (2017 EPA-USDA Reference Guide). This reference 
guide discusses air quality conservation measures relating to nutrition 
and feed management, animal confinement, manure management, land 
application, and other supplemental practices. Among other things it 
includes Appendix A.1 (``Table of Mitigation Effectiveness for Selected 
Measures''), which lists 12 measures that may reduce ammonia emissions 
by more than 30%, Appendix A.2 (``List of State Programs and 
Regulations for AFO Air Emissions''), and Appendix A.3 (``List of AFO 
Air Quality Programs & Land-Grant Universities'').
    In sum, various research studies on mitigating ammonia emissions 
from CAFs suggest that there may be potential for additional ammonia 
reductions from activities such as animal feeding and housing to manure 
storage, handling, and land application. While the Plan refers to and 
describes some of the research studies described herein (e.g., the 2008 
Alberta Report and the 2005 Chadwick paper), it is unclear the extent 
to which the higher emission reduction measures have been or could be 
implemented in the SJV and, when aggregated across all CAF operations, 
it remains unclear whether the total reduction from additional measures 
would be greater than the State's estimate of maximum available

[[Page 60506]]

reductions.\91\ Accordingly, the EPA concludes that the available 
information in the Plan is insufficient to conclude that the State has 
sufficiently examined and justified its estimate for the ammonia 
emission reductions that may be available from CAFs, which emit a 
majority of the ammonia in the SJV.
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    \91\ In evaluating the aggregate reductions available across all 
sub-activities, it may be important to evaluate the extent to which 
reductions at one sub-activity may affect emissions at other stages 
of the process.
---------------------------------------------------------------------------

    Regarding fertilizer application, Rule 4570 and Rule 4565 have 
provisions addressing the land application of manure from CAFs and of 
biosolids, animal manure, and poultry litter from composting operations 
(though these lack specific enforceable requirements for ammonia). 
However, more broadly, the District states that fertilizer application 
is the second largest ammonia source in the SJV and that the District 
does not have statutory authority to regulate such activities.\92\ 
Notwithstanding this statement, the District describes key research 
assessing nitrogen in California, as well as regulations adopted by the 
California Water Resources Control Board, including orders adopted by 
the Central Valley Regional Water Quality Control Board (e.g., a 
Nutrient Management Plan), the Irrigated Lands Regulatory Program 
(e.g., a Nitrogen Management Plan), or other individual mechanisms.\93\ 
These orders subject agricultural operators, including dairies, bovine 
feedlots, poultry operations, and crop farmers to ``waste discharge 
requirements that protect both surface water and groundwater.'' \94\
---------------------------------------------------------------------------

    \92\ 2018 PM2.5 Plan, App. C, C-311.
    \93\ 2018 PM2.5 Plan, App. C, C-339 to C-343.
    \94\ Id. at C-341.
---------------------------------------------------------------------------

    The EPA anticipates that such regulations are, in practice, likely 
to enhance the retention of nitrogen (whether from manure or nitrogen-
based chemical fertilizers) for productive purposes in the SJV (e.g., 
growing crops and enhancing soil health) and limit the loss of nitrogen 
as pollution to water and air (e.g., potentially reduce ammonia 
emissions). However, to our knowledge, these regulations do not impose 
any enforceable requirement for ammonia emissions to the air, and thus 
render quantification difficult, as with Rule 4570.\95\
---------------------------------------------------------------------------

    \95\ Unlike Rule 4570, which has been approved into the 
California SIP to limit VOC emissions, the State's water-related 
regulations on fertilizer application have not been submitted for 
approval into the California SIP.
---------------------------------------------------------------------------

    In addition, the District states that ``the overall efficiency of 
nitrogen usage at California farms is expected to increase and 
emissions of reactive nitrogen, including [ammonia], are expected to 
decrease significantly.'' We agree that managing the amount of nitrogen 
applied to the environment should reduce the potential for pollution to 
air, water, and land. However, the District does not attempt to 
quantify or otherwise substantiate the scale and timing of such 
potential ammonia emission reduction benefits, nor their 
enforceability, nor does it attempt to analyze how much additional 
reductions may be available. Overall, the EPA finds that the available 
evidence is insufficient to conclude that the State has sufficiently 
examined and justified its estimate for the ammonia emission reductions 
that may be available from fertilizer application, the second largest 
ammonia emission source in the SJV.
c. The EPA's Conclusion for Ammonia Precursor Demonstration
    The EPA does not believe that the State has presented sufficient 
evidence that ammonia does not contribute significantly to 
PM2.5 levels above the NAAQS. In the absence of an approved 
precursor demonstration, ammonia remains a plan precursor subject to 
the requirements of BACM, BACT, and additional feasible measures.
    As discussed in our 2021 Proposed Rule,\96\ the modeled response to 
30% ammonia emissions reductions is above the EPA's recommended 
contribution threshold of 0.20 [micro]g/m\3\ at two monitoring sites, 
Madera and Hanford, providing evidence that ammonia significantly 
contributes to PM2.5 in SJV. In the previous proposal, we 
gave those responses less weight, because of specific evidence 
available for these sites that the responses were overestimated. For 
Madera, the monitoring data used in estimating the model response are 
biased high, and therefore the modeled response of 0.21 [micro]g/m\3\, 
just above contribution threshold, is likely overestimated. For 
Hanford, several analyses showed ambient ammonia concentrations are 
underestimated, and so we believe that the modeled response of 0.26 
[micro]g/m\3\ is likely overestimated. Supporting that conclusion is 
the evidence from ambient concentrations of excess ammonia relative to 
nitrate, which suggest that PM2.5 responses to reductions of 
ammonia emissions would be dampened by the NOX-limited 
nature of ammonium nitrate formation in the SJV.
---------------------------------------------------------------------------

    \96\ 86 FR 74310, 74320.
---------------------------------------------------------------------------

    All of those considerations remain for the current proposal. But in 
light of comments received and re-evaluation of the available evidence, 
the EPA believes we should give the Hanford response more weight, 
because that response would be larger if the ammonia reductions modeled 
were larger than the 30% assumed in the State's precursor 
demonstration. The previous subsection gave several examples of the 
uncertainty and possible underestimation of the ammonia benefit of 
available control measures to the SJV. The EPA does not believe there 
is sufficient quantitative evidence to rely on 30% as the amount of 
achievable reductions, and as the amount to use an upper bound on the 
ammonia emission reductions modeled in the State's precursor 
demonstration. A robust controls evaluation could show that a larger 
amount of reductions is achievable. If it is, then not only would the 
Hanford modeled response be larger, but additional monitoring sites 
could have a modeled response above the contribution threshold.
    For example, with respect to the modeled 2024 ambient 
PM2.5 responses to a 70% emission reduction, we note that 
the modeled high site of Bakersfield-Planz would have a response of 
0.36 [micro]g/m\3\, the site with the largest modeled response would be 
0.75 [micro]g/m\3\ at Hanford, and six sites (including Hanford) would 
have modeled responses greater than 0.5 [micro]g/m\3\. As a more modest 
example, interpolating between the available 30% and 70% modeled 
results, if 32% reductions are achievable, then three additional 
monitoring sites (Turlock, Merced-S. Coffee St., and Modesto) would 
reach the 0.2 [micro]g/m\3\ contribution threshold. The uncertainty 
over the ammonia response means that we cannot rely on 30% as an upper 
bound for ammonia emission reductions, and so the weight of evidence 
shifts relative to that in the 2021 Proposed Rule.
    The discussion in this proposed rule, and the heavy reliance in the 
2021 Proposed Rule, on the State's use of a 30% upper bound for 
potential reduction from controls should not be interpreted as 
establishing a 30% ``bright line'' for deciding whether a precursor 
should be regulated. The PM2.5 Precursor Guidance recommends 
that 30% to 70% emissions reductions be modeled as a way of 
implementing the PM2.5 SIP Requirements Rule's option in 40 
CFR 51.1006(a)(1)(ii) for a State to assess the sensitivity of the 
atmospheric PM2.5 to precursor emission reductions. The 
sensitivity of the atmosphere to reductions is a separate question from 
what reductions are achievable from controls; the latter is properly 
part of the control evaluation for BACM, BACT, and additional feasible 
measures. However, it is important to note that under 40 CFR

[[Page 60507]]

51.1010(a)(2)(ii), the EPA may require a control evaluation to help the 
EPA evaluate the precursor demonstration. The PM2.5 
Precursor Guidance explains that the additional information from a 
control evaluation is particularly important when modeled precursor 
contributions are close to the threshold for a 30% reduction.\97\ But 
the regulations and guidance do not establish an automatic ``off ramp'' 
for a State to be discharged from the requirements for BACM, BACT, and 
additional feasible measures via a showing that achievable reductions 
are below a particular percentage.
---------------------------------------------------------------------------

    \97\ PM2.5 Precursor Guidance, 31.
---------------------------------------------------------------------------

    We have no evidence that emission reductions below current 
emissions levels from BACM on all ammonia sources in the SJV would be 
as large as 70%, but the lack of a developed record showing what 
ammonia control measures are feasible and what they could achieve makes 
it harder for the EPA to assess this point. We also lack sufficient 
evidence to conclude that reasonable ammonia control measures could 
achieve no more than 30% reductions, and so cannot rely on that 
supposition in weighing the modeled responses to reductions and other 
evidence. Better quantification of the possible ammonia reductions from 
current levels that could result from additional controls would help 
resolve this issue. Reconciliation of modeled sensitivity with that 
expected from ambient studies would also be appropriate.
    The EPA has re-examined the 2024 sensitivity analyses to both 30% 
and 70% ammonia emission reductions in light of the uncertainty that 
30% represents a reasonable upper bound for potential ammonia emission 
reductions. We note that the State modeled 30% reduction scenarios and 
predicted ambient PM2.5 responses above 0.2 [micro]g/m\3\ at 
2 of 15 sites in 2024; and modeled the 70% reduction scenarios and 
predicted responses above 0.2 [micro]g/m\3\ at all monitors in 
2024.\98\ The EPA maintains that the State's reliance on its 
sensitivity-based contribution analysis for a future year (2024) to 
evaluate the significance of ammonia as a precursor is reasonable, well 
supported, and consistent with the EPA's guidance. There are also good 
reasons for giving less weight to the modeled responses at the Madera 
and Hanford sites, although those are tempered by the consideration 
that there is not good support for limiting the modeled ammonia 
reductions to 30%, leading to the possibility of larger responses at 
Hanford and of additional sites with responses above the contribution 
threshold.
---------------------------------------------------------------------------

    \98\ 2018 PM2.5 Plan, App. G, tables 4 through 7.
---------------------------------------------------------------------------

    The weight of the evidence, including at least one site above the 
EPA's recommended contribution threshold and the possibility of 
additional ones depending on the unknown amount of reductions 
achievable, favor retaining the presumption that ammonia must be 
regulated as a PM2.5 precursor for the 2012 annual 
PM2.5 NAAQS in the SJV. For the reasons explained above, the 
Plan both indicates that there are levels of ammonia control that could 
have a significant impact on PM2.5 levels at multiple 
monitors in the SJV and does not dispose the potential availability of 
ammonia emission reductions at a level that would have such impacts. 
Therefore, the EPA proposes to disapprove the State's ammonia precursor 
demonstration for the Serious area requirements for purposes of the 
2012 annual PM2.5 NAAQS in the SJV.

B. Best Available Control Measures

1. Statutory and Regulatory Requirements
    Section 189(b)(1)(B) of the Act requires for any Serious 
PM2.5 nonattainment area that the State submit provisions to 
assure that the best available control measures (BACM), including 
controls that reflect best available control technology (BACT), for the 
control of PM2.5 and PM2.5 precursors shall be 
implemented no later than four years after the date the area is 
reclassified as a Serious area. The EPA has defined BACM in the 
PM2.5 SIP Requirements Rule to mean ``any technologically 
and economically feasible control measure that can be implemented in 
whole or in part within 4 years after the date of reclassification of a 
Moderate PM2.5 nonattainment area to Serious and that 
generally can achieve greater permanent and enforceable emissions 
reductions in direct PM2.5 emissions and/or emissions of 
PM2.5 plan precursors from sources in the area than can be 
achieved through the implementation of reasonably available control 
measures (RACM) on the same source(s).'' \99\
---------------------------------------------------------------------------

    \99\ 40 CFR 51.1000 (definitions). In longstanding guidance, the 
EPA has similarly defined BACM to mean, ``among other things, the 
maximum degree of emissions reduction achievable for a source or 
source category, which is determined on a case-by-case basis 
considering energy, environmental, and economic impacts.'' General 
Preamble Addendum, 42010, 42013.
---------------------------------------------------------------------------

    The EPA generally considers BACM a control level that goes beyond 
existing RACM-level controls, for example by expanding the use of RACM 
controls or by requiring preventative measures instead of 
remediation.\100\ Indeed, because states are required to implement BACM 
and BACT when a Moderate nonattainment area is reclassified as Serious 
due to its inability to attain the NAAQS through implementation of 
``reasonable'' measures, it is logical that ``best'' control measures 
should represent a more stringent and potentially more technologically 
advanced or more costly level of control.\101\ If RACM and RACT level 
controls of emissions have been insufficient to reach attainment, then 
the CAA Title I, Part D, subpart 4 provisions for PM2.5 
nonattainment plans contemplate the implementation of more stringent 
controls, controls on more sources, or other adjustments to the control 
strategy necessary to attain the NAAQS in the area. Thus, BACM/BACT 
determinations are to be ``generally independent'' of attainment for 
purposes of implementing the PM2.5 NAAQS.\102\
---------------------------------------------------------------------------

    \100\ 81 FR 58010, 58081 and General Preamble Addendum, 42011, 
42013.
    \101\ 81 FR 58010, 58081 and General Preamble Addendum, 42009-
42010.
    \102\ PM2.5 SIP Requirements Rule, 58081-58082. See 
also, General Preamble Addendum, 42011.
---------------------------------------------------------------------------

    Consistent with longstanding guidance provided in the General 
Preamble Addendum, the preamble to the PM2.5 SIP 
Requirements Rule discusses the following steps for states to use in 
identifying and selecting the emission controls needed to meet the 
BACM/BACT requirements of 40 CFR 51.1010:
    1. Develop a comprehensive emission inventory of all sources of 
PM2.5 and PM2.5 precursors from major and non-
major stationary point sources, area sources, and mobile sources;
    2. Identify potential control measures for all sources or source 
categories of emissions of PM2.5 and relevant 
PM2.5 plan precursors;
    3. Determine whether an available control measure or technology is 
technologically feasible;
    4. Determine whether an available control measure or technology is 
economically feasible; and
    5. Determine the earliest date by which a control measure or 
technology can be implemented in whole or in part.\103\
---------------------------------------------------------------------------

    \103\ 81 FR 58010, 58083-58085.
---------------------------------------------------------------------------

    The EPA allows states to consider factors such as a source's 
processes and operating procedures, raw materials, physical plant 
layout, and potential environmental impacts such as increased water 
pollution, waste disposal, and energy requirements when

[[Page 60508]]

considering technological feasibility.\104\ For purposes of evaluating 
economic feasibility, the EPA allows states to consider factors such as 
the capital costs, operating and maintenance costs, and cost 
effectiveness (i.e., cost per ton of pollutant reduced by a measure or 
technology) associated with the measure or control.\105\ For any 
potential control measure identified through the process described 
above that is eliminated from consideration, states are required to 
provide detailed written justification for doing so on the basis of 
technological or economic feasibility, including how its criteria for 
determining such feasibility are more stringent than those used for 
determining RACM/RACT.\106\
---------------------------------------------------------------------------

    \104\ 40 CFR 51.1010(a)(3)(i).
    \105\ 40 CFR 51.1010(a)(3)(ii).
    \106\ 40 CFR 51.1010(a)(3)(iii).
---------------------------------------------------------------------------

    Once these analyses are complete, the State must use this 
information to develop enforceable control measures for all relevant 
source categories in the nonattainment area and submit them to the EPA 
for evaluation as SIP provisions to meet the basic requirements of CAA 
section 110 and any other applicable substantive provisions of the Act.
2. BACM for Ammonia Sources
    As previously noted, as part of the EPA's 2021 Proposed Rule, we 
reviewed the State's analysis of ammonia control for the primary source 
categories of ammonia in the context of our evaluation of the State's 
precursor demonstration.\107\ Because our prior proposal to approve the 
State's ammonia precursor demonstration would have relieved the State 
of its obligation to implement BACM for ammonia sources, we did not 
present a summary of the 2018 PM2.5 Plan with respect to the 
BACM requirements for ammonia for the 2012 annual PM2.5 
NAAQS, nor our evaluation thereof. Given our reconsidered proposal to 
disapprove the State's ammonia precursor demonstration, in the 
following sections of this proposed rule we evaluate the District's 
control analysis for the two most substantial source categories of 
ammonia, which together sum to more than 90% of the emissions in the 
SJV: CAFs and fertilizer application.
---------------------------------------------------------------------------

    \107\ 86 FR 74310, 74319. See also, 85 FR 17382, 17395 (March 
27, 2020), and the EPA's PM2.5 Precursor TSD, 13.
---------------------------------------------------------------------------

a. Summary of State's Submission
    The District presents its analysis of ammonia controls for the 
primary ammonia source categories in the SJV in Appendix C, section 
C.25 (``Ammonia in the San Joaquin Valley'') of the 2018 
PM2.5 Plan. The District evaluated its emission control 
measures for compliance with BACM for CAFs and described water-related 
measures applicable to fertilizer application that have co-benefits to 
air quality. The District presents its reasoning that measures that 
control VOC emissions, such as Rule 4570 for CAFs, also reduce ammonia 
emissions due to the physical processes occurring in decomposing manure 
and subsequent volatilization of decomposition products (like VOC and 
ammonia). As part of its process for identifying candidate BACM, 
considering the technical and economic feasibility of additional 
control measures, the District reviewed the EPA's guidance documents on 
BACM, and control measures implemented in other nonattainment areas in 
California and other states.\108\
---------------------------------------------------------------------------

    \108\ 2018 PM2.5 Plan, Chapter 4, section 4.3.1.
---------------------------------------------------------------------------

    For CAFs, the District discusses in detail how Rule 4570 
(``Confined Animal Facilities'') is structured (e.g., to address 
varying types of CAFs, including applicability thresholds); the five 
main CAF operations/emission sources: feeding, housing (including 
distinctions for housing configurations), solid waste, liquid waste, 
and land application of manure; and the control menu requirements for 
each of those five operations.\109\ The District summarizes the 
specific requirements applicable to each type of cattle-based CAF, 
including dairies, beef feedlots, and ``other cattle'' and describes 
its basis for ammonia emission reductions estimates, including cited 
research papers.
---------------------------------------------------------------------------

    \109\ 2018 PM2.5 Plan, App. C, C-312 to C-323.
---------------------------------------------------------------------------

    The District also compares Rule 4570 to other CAF rules imposed by 
the South Coast Air Quality Management District (AQMD), Bay Area AQMD, 
Sacramento Metropolitan AQMD, Imperial County Air Pollution Control 
District (APCD), and the State of Idaho.\110\ The District evaluates a 
potential additional control measure--application of sodium bisulfate 
to reduce pH and bacterial levels in bedding for dairy cattle--and 
concludes that such measure is not feasible based on a number of 
factors, including health and safety of dairy workers and animals, 
impacts on water quality, and overall cost and effectiveness.\111\
---------------------------------------------------------------------------

    \110\ 2018 PM2.5 Plan, App. C, C-323 to C-337.
    \111\ 2018 PM2.5 Plan, App. C, C-338 to C-339.
---------------------------------------------------------------------------

    For fertilizer application, as described in section II.A.3 of this 
proposed rule, the District states that fertilizer application is the 
second largest ammonia source in the SJV and that the District does not 
have statutory authority to regulate such activities.\112\ 
Notwithstanding, the District describes how regulations adopted by the 
California Water Resources Control Board, including orders adopted by 
the Central Valley Regional Water Quality Control Board (e.g., a 
Nutrient Management Plan), the Irrigated Lands Regulatory Program 
(e.g., a Nitrogen Management Plan), or other individual mechanisms 
\113\ subject agricultural operators, including dairies, bovine 
feedlots, poultry operations, and crop farmers to ``waste discharge 
requirements that protect both surface water and groundwater.'' \114\
---------------------------------------------------------------------------

    \112\ 2018 PM2.5 Plan, App. C, C-311.
    \113\ 2018 PM2.5 Plan, App. C, C-339 to C-343.
    \114\ 2018 PM2.5 Plan, App. C, C-341.
---------------------------------------------------------------------------

    Overall, the District concludes that ``the Valley's ammonia 
emissions have been significantly reduced through stringent 
regulations, that additional ammonia control measures are infeasible, 
and that Valley sources are already implementing BACM.'' \115\
---------------------------------------------------------------------------

    \115\ 2018 PM2.5 Plan, App C., C-312.
---------------------------------------------------------------------------

b. Summary of Adverse Comments
    Public Justice states that ``[w]eaker controls are consistently 
allowed for agricultural sources,'' including an ``expansive menu of 
control options'' in Rule 4570, that they assert provide little to no 
emission reduction benefit.\116\ More broadly, as described in section 
II.A.2 of this proposed rule, the commenters assert that ``[t]he 
analysis of potential controls is particular[ly] weak and ignores the 
wealth of literature demonstrating that strategies for reducing ammonia 
emissions from agriculture . . . are among the most effective for also 
reducing PM concentrations,'' and cite several studies in support of 
this argument.\117\ The commenters further state that reducing ammonia 
emissions may be achieved through ``strategies such as improving 
livestock feed to reduce excreted nutrients, altering manure storage 
and handling practices to prevent [ammonia] emissions, and improving 
synthetic fertilizer use efficiency,'' again citing numerous 
studies.\118\ The commenters

[[Page 60509]]

argue that the EPA ``should reject the plan's BACM analysis for failing 
to justify these weaker controls, and for being inconsistent with the 
Title VI prohibition against policies and practices that inflict 
disparate impacts.''
---------------------------------------------------------------------------

    \116\ Public Justice Comment Letter, 20.
    \117\ Public Justice Comment Letter, 16, Exhibits 31 through 34.
    \118\ Public Justice Comment Letter, 17, Exhibits 35 through 40 
and three additional studies: N. Cole, et al., ``Influence of 
dietary crude protein concentration and source on potential ammonia 
emissions from beef cattle manure,'' J. Anim. Sci. 83, 722, 2005; N. 
Cole, P. Defoor, M. Galyean, G. Duff, J. Gleghorn, ``Effects of 
phase-feeding of crude protein on performance, carcass 
characteristics, serum urea nitrogen concentrations, and manure 
nitrogen of finishing beef steers,'' J. Anim. Sci. 12, 3421-3432, 
2006; and R. Todd, N. Cole, R. Clark, ``Reducing crude protein in 
beef cattle diet reduces ammonia emissions from artificial feedyard 
surfaces,'' J. Environ. Qual. 35, 404-411, 2006.
---------------------------------------------------------------------------

c. The EPA's Reconsidered Proposal
    As a result of our proposed conclusion that ammonia remains a 
regulated precursor for the 2012 annual PM2.5 NAAQS in the 
SJV, the EPA has evaluated potential ammonia emissions control measures 
for the two most substantial source categories in the SJV and evaluated 
whether the State has implemented ammonia controls with a BACM/BACT 
level of stringency. Thus, the EPA has also evaluated the existing 
control measures that the State claims are BACM for two of the main 
sources of ammonia in the area, including confined animal facilities 
(CAFs) and fertilizer application.\119\ As discussed below, we conclude 
that the SJV has not established that it has enforceable requirements 
in the SIP that meet a BACM level of stringency to reduce ammonia 
emissions from these two categories. Therefore, we propose to 
disapprove BACM for ammonia sources in the SJV.
---------------------------------------------------------------------------

    \119\ By focusing on these two source categories, the EPA is not 
indicating that this is an exhaustive list of ammonia source 
categories that must be evaluated for BACM. However, because these 
two categories amount to more than 90% of the ammonia emissions in 
the SJV, we focus our analysis on these two categories.
---------------------------------------------------------------------------

    Our basis for proposing to disapprove BACM for ammonia sources 
flows from the controls analysis we have reviewed and discuss in 
section II.A.3 of this proposed rule. We agree with the commenters that 
the analysis of potential controls in the 2018 PM2.5 Plan 
was weak in two general areas: (1) incomplete quantification of 
existing ammonia emission reductions, and (2) lack of consideration of 
potential ammonia control measures identified in research studies. In 
that section we describe the Plan's weaknesses with respect to 
quantifying emission reductions and rely on that description for 
purposes of evaluating BACM.
    Similarly, in section II.A.3, we discuss additional options for 
ammonia control that we will not reiterate here. Based on our review of 
the additional research studies cited by the commenters with respect to 
CAFs, measures such as those for adjusting the protein content of 
livestock feed (e.g., reducing the portion of beef cattle finishing 
diets by 1.5% steam-flaked corn), manure handling and storage (e.g., 
washing dairy cow collecting yards after each milking event, covering 
solid manure stores with sheeting), and land application of slurry 
(e.g., injection application techniques), it appears that additional 
measures may be available to evaluate. Absent a thorough and more 
current evaluation of technological and economic feasibility of 
potential measures as applied in the SJV, we propose to find that the 
State has not demonstrated whether or how additional measures (e.g., in 
the form of existing options that could also be feasibly implemented, 
or new options that may lead to increased reductions) may have been 
evaluated, implemented (even partially) by the existing rules, or set 
aside for reasons of technological feasibility or economic feasibility, 
consistent with the BACM requirements.
    For fertilizer application, as discussed in section II.A.3 of this 
proposed rule, the District indicates that it does not have authority 
to regulate ammonia emissions from fertilizer application. Regardless 
of which State entity, as a matter of State law, has authority over 
this class of activities, CAA section 189(b)(1) requires that the State 
include provisions to ensure implementation of BACM for direct 
PM2.5 and plan precursor emissions, and CAA section 
110(a)(2)(E)(i) requires the State to provide necessary assurances that 
it has adequate authority to carry out the implementation plan for the 
area. While the Plan describes certain water-related measures (e.g., 
Nutrient Management Plans and Nitrogen Management Plan) that subject 
agricultural operators, including dairies, bovine feedlots, poultry 
operations, and crop farmers to waste discharge requirements, and 
likely limit ammonia emissions to the air, to our knowledge, these 
regulations do not impose any enforceable requirement for ammonia 
emissions to the air, and thus suffer a similar problem as Rule 
4570.\120\
---------------------------------------------------------------------------

    \120\ Unlike Rule 4570, which has been approved into the 
California SIP to limit VOC emissions, the State's water-related 
regulations on fertilizer application have not been submitted for 
approval into the California SIP.
---------------------------------------------------------------------------

    We agree that as a general matter, managing the amount of nitrogen 
applied to the environment should reduce the potential for pollution to 
air, water, and land. However, the 2018 PM2.5 Plan does not 
quantify or otherwise substantiate the scale and timing of such 
potential ammonia emission reduction benefits, nor their 
enforceability. We propose that the State has not adequately identified 
potential control measures, evaluated for BACM/BACT, nor demonstrated 
the implementation of BACM/BACT for controlling ammonia emissions from 
fertilizer application, the second largest source of such emissions in 
the SJV.
    As a result of our proposal that the State has not demonstrated 
that BACM/BACT controls are in place for CAFs and fertilizer 
application, two source categories that make up more than 90% of the 
ammonia emissions in the SJV, we propose to disapprove the State's BACM 
demonstration for ammonia sources.
3. BACM for Building Heating Emission Sources
a. Summary of 2021 Proposed Rule
    In our 2021 Proposed Rule, the EPA summarized the State's 
submission in the 2018 PM2.5 Plan for the SJV and presented 
our BACM evaluation for emission sources of direct PM2.5 and 
NOX.\121\ We briefly summarize those components here with 
respect to the State's BACM demonstration for building heating emission 
sources, such as water heaters and space heaters (e.g., furnaces), in 
the SJV.
---------------------------------------------------------------------------

    \121\ 86 FR 74310, 74324-74325.
---------------------------------------------------------------------------

    In Appendix C of the 2018 PM2.5 Plan, the District 
identifies the stationary and area sources of direct PM2.5 
and NOX in the SJV that are subject to District emission 
control measures and provides its evaluation of these regulations for 
compliance with BACM requirements. As part of its process for 
identifying candidate BACM, the District reviewed the EPA's guidance 
documents on BACM, additional guidance documents on control measures 
for direct PM2.5 and NOX emission sources, and 
control measures implemented in other ozone and PM2.5 
nonattainment areas in California and other states.\122\ Based on these 
analyses, the District concludes that all best available control 
measures for stationary and area sources are in place in the SJV for 
NOX and directly emitted PM2.5 for purposes of 
meeting the BACM/BACT requirement for the 2012 annual PM2.5 
NAAQS.
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    \122\ 2018 PM2.5 Plan, Ch. 4, section 4.3.1.
---------------------------------------------------------------------------

    With respect to building heating emission sources, the District 
presents its evaluations of Rule 4902 (``Residential Water Heaters'') 
and Rule 4905 (``Natural Gas-Fired, Fan-Type Central Furnaces'') in 
sections C.20 and C.21, respectively, of Appendix C of the 2018 
PM2.5 Plan. Both rules are point of sale rules that limit 
what kinds of residential water heaters and furnaces may be sold in the 
SJV. The District describes the types of equipment covered by each 
rule, compares the specific provisions of each rule that

[[Page 60510]]

limit NOX emissions \123\ to comparable rules in other 
California air districts, and concludes that each rule represents BACM 
for their respective source category.
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    \123\ The District notes that equipment subject to Rule 4902 are 
fired on natural gas that meets California Public Utility Commission 
standards and, therefore, emit only low amounts of SOX 
and direct PM2.5. 2018 PM2.5 Plan, App. C, C-
288.
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    Rule 4902 applies to natural gas-fired, residential water heaters 
with heat input rates less than or equal to 75,000 British thermal 
units per hour (Btu/hr). The District tightened the rule's 
NOX limits in 2009; and the EPA approved the rule into the 
SIP in 2010.\124\ The District estimates that, due to Rule 4902, annual 
average emissions of NOX would decrease from 2.15 tpd in 
2013 to 1.91 tpd in 2025 (0.24 tpd decrease) and annual average 
emissions of direct PM2.5 would increase from 0.21 tpd in 
2013 to 0.23 tpd in 2025 (0.02 tpd increase).\125\
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    \124\ 75 FR 24408 (May 5, 2010).
    \125\ 2018 PM2.5 Plan, App. C, C-283.
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    In addition to comparing the NOX limits in its Rule 4902 
to rules in other California air districts, the District also presents 
a multi-factor comparison of natural gas-fired and propane-fired, water 
heaters to electric water heaters.\126\ The District discussed the 
likely impacts of requiring electric water heaters, including the 
advantages such as no NOX emissions,\127\ less expensive 
purchase price, and smaller size, and the disadvantages such as higher 
cost of electricity, and the costs of residence modifications to 
convert to electric. Based on 2017-2018 data, which is consistent with 
the timing of Plan adoption in 2018, the District calculated emission 
reductions and cost effectiveness of the three kinds of water heaters 
by fuel type and concluded that ``[w]hile the lifetime cost of an 
electric water heater is higher than that of propane and natural gas, 
the emissions benefits may make converting to electric water heating a 
viable control strategy.'' \128\ The analysis does not explore the cost 
effectiveness of such controls and Rule 4902 does not include any 
requirements regarding electrification.
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    \126\ 2018 PM2.5 Plan, App. C, C-288 to C-289.
    \127\ The EPA notes that while the NOX emissions of 
electric water heaters and furnaces are zero, there could be an 
increase in NOX emissions from electric power plants.
    \128\ 2018 PM2.5 Plan, App. C, C-289.
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    Rule 4905 applies to natural gas-fired, fan-type central furnaces 
with heat input rates less than 175,000 Btu/hr and combination heating 
and cooling units with a rated cooling capacity of less than 65,000 
Btu/hr. In 2015, the District tightened the rule's NOX 
limits for residential units and expanded the rule to include 
commercial units and manufactured homes according to a phase-in 
schedule. The EPA approved the rule into the SIP in 2016.\129\ The 
District estimates that, due to Rule 4905, annual average emissions for 
NOX will decrease from 2.44 tpd in 2013 to 2.13 tpd in 2025 
(0.31 tpd decrease) and annual average emissions for direct 
PM2.5 will increase from 0.20 tpd in 2013 to 0.22 tpd in 
2025 (0.02 tpd increase).\130\ Given the need to extend certain 
compliance deadlines in subsequent amendments to Rule 4905 due to 
limited supply of certified compliant units,\131\ the District states 
that it had identified no additional emission reduction measures for 
this source category as of that point in time.\132\
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    \129\ 81 FR 17390 (March 29, 2016).
    \130\ 2018 PM2.5 Plan, App. C, C-290.
    \131\ The District further amended Rule 4902 in 2018, 2020, and 
2021 to extend the compliance deadline for specific units due to 
limited supply of certified compliant units, with each amendment 
applying to a smaller subset of those specific units. See, e.g., San 
Joaquin Valley UAPCD, ``Item Number 10: Adopt Proposed Amendments to 
Rule 4905 (Natural Gas-Fired, Fan-Type Central Furnaces),'' December 
16, 2021, 2-3.
    \132\ 2018 PM2.5 Plan, App. C, C-293. Unlike the 
District's consideration of electric water heaters, the District did 
not present an evaluation of electric furnaces in its analysis of 
Rule 4905.
---------------------------------------------------------------------------

    As noted in the EPA's 2021 Proposed Rule, we provided our 
evaluation of the District's BACM demonstration for stationary and area 
sources in general, and several source categories in more detail, in 
three documents: (1) section III of the EPA's ``Technical Support 
Document, EPA Evaluation, San Joaquin Valley Serious Area Plan for the 
2012 Annual PM2.5 NAAQS,'' December 2021 (``EPA's 2012 
Annual PM2.5 TSD''); (2) the EPA's ``Technical Support 
Document, EPA Evaluation of BACM/MSM, San Joaquin Valley 
PM2.5 Plan for the 2006 PM2.5 NAAQS,'' February 
2020 (``EPA's BACM/MSM TSD''); and (3) the EPA's ``Response to Comments 
Document for the EPA's Final Action on the San Joaquin Valley Serious 
Area Plan for the 2006 PM2.5 NAAQS,'' June 2020 (``EPA's 
2020 Response to Comments''). In particular, the EPA's 2020 Response to 
Comments presented our evaluation of the District's BACM demonstration 
for residential water heaters and residential and commercial, natural 
gas-fired, fan-type central furnaces.\133\ At that time we found that 
the requirements for residential fuel combustion covered by Rule 4902 
and Rule 4905 represented BACM.\134\ In addition, the EPA concluded 
that setting a zero-NOX standard for heating appliances in 
new buildings reasonably requires additional consideration and analysis 
of technological and economic feasibility by the District because, per 
the 2018 PM2.5 Plan, the most common types of residential 
water heaters and furnaces are those that use natural gas as fuel.
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    \133\ EPA's 2020 Response to Comments, Comment 6.O and Response 
6.O, 142-148.
    \134\ EPA's 2020 Response to Comments, 146-147.
---------------------------------------------------------------------------

    We also noted that the building codes referenced by commenters at 
that time appear to be green building code ordinances that restrict or 
prohibit installation of natural gas or propane appliances in new 
construction.\135\ Such ordinances, most of which appeared to have been 
adopted in late 2019 and early 2020, fell within a category known as 
``reach codes,'' which are city and county building code standards for 
energy efficiency that exceed California's State-wide standards. We 
stated that California law requires local governments to submit 
proposed ordinances to the California Energy Commission (CEC) for a 
determination that they will be both cost effective and more energy 
efficient than statewide standards; compliance with this procedure is 
necessary for such measures to be enforceable.\136\ We also noted that 
ordinances adopted by city councils and county officials are legally 
distinct from measures adopted by the governing boards of the 
respective air districts and that it did not appear at the time that 
California air districts had adopted similar restrictions.
---------------------------------------------------------------------------

    \135\ EPA's 2020 Response to Comments, 147-148.
    \136\ California 2019 Building Energy Standards, at California 
Code of Regulations (CCR), Title 24, Part 1, Article 1, Sec. 10-106 
(``Locally Adopted Energy Standards''); see also https://ww2.energy.ca.gov/title24/2016standards/ordinances.
---------------------------------------------------------------------------

b. Summary of Adverse Comments
    Public Justice states that further emission controls are available 
for building heating via the electrification of furnaces, water 
heaters, and other gas-fired appliances.\137\ The commenters refer to 
comments submitted by a group of environmental, public health, and 
community organizations (collectively referred to herein as ``NPCA'') 
on the EPA's proposed rule on the 2006 24-hour PM2.5 NAAQS 
portion of the SJV PM2.5 Plan,\138\ noting that building 
electrification requirements to reduce emissions from such sources 
already

[[Page 60511]]

exist in over 30 jurisdictions in California and other states. The 
commenters state that, since that time, additional jurisdictions have 
moved forward with gas bans, appliance standards, and other strategies 
for building heating.\139\
---------------------------------------------------------------------------

    \137\ Public Justice Comment Letter, 19.
    \138\ Comment letter dated and received April 27, 2020, from 
Mark Rose, NPCA, et al., to Rory Mays, EPA, including Appendices A 
through G. The seven environmental and community organizations, in 
order of appearance in the letter, are the National Parks 
Conservation Association (NPCA), Earthjustice, Central Valley Air 
Quality Coalition, Coalition for Clean Air, Central Valley 
Environmental Justice Network, The Climate Center, and Central 
Valley Asthma Collaborative (collectively ``NPCA'').
    \139\ Public Justice Comment Letter, 19, and Exhibits 41 through 
44. Commenters also state that studies suggest these measures may 
provide particularly notable benefits to winter PM2.5 
peaks in the SJV. Id. at 19.
---------------------------------------------------------------------------

    With respect to the EPA's response to the NPCA comments in 
2020,\140\ Public Justice argues that the ``EPA merely asserted that 
the District had found increased building electrification infeasible,'' 
despite the record showing that other jurisdictions required such 
measures, and assert that the District noted the potential of such 
measures but rejected them without explanation. The commenters further 
argue that the EPA did not rebut evidence on the benefits and 
feasibility of such measures, instead noting the need for further 
consideration, and that two years later, the Plan does not provide 
further consideration.
---------------------------------------------------------------------------

    \140\ EPA, ``Response to Comments Document for the EPA's Final 
Action on the San Joaquin Valley Serious Area Plan for the 2006 
PM2.5 NAAQS,'' June 2020. See Comment 6.O and Response 
6.O on pages 142-147.
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c. The EPA's Reconsidered Proposal
    Based on the adverse comments from Public Justice, the EPA has 
reconsidered our proposed approval of the State's demonstration of BACM 
for NOX and direct PM2.5 emissions from building 
heating appliances, such as residential water heating and residential 
and commercial space heating. As discussed below, we now propose to 
disapprove the State's BACM demonstration for such building heating 
emission sources.
    Although the EPA has previously approved the State's BACM 
demonstration for building heating emission sources in 2020 with 
respect to the 2006 24-hour PM2.5 NAAQS portion of the 2018 
PM2.5 Plan, and such approval was upheld by the Ninth 
Circuit Court of Appeals,\141\ several factors have reshaped the facts 
and circumstances of controlling emissions from such sources as of 2022 
and beyond. First, while building ordinances that restrict or prohibit 
installation of natural gas or propane appliances in new construction 
were starting to appear in 2019 and 2020, as Public Justice correctly 
asserts, two additional years have passed and additional jurisdictions 
have adopted gas bans, appliance standards, and other strategies for 
building heating.\142\ A recent policy brief published by the UCLA 
School of Law states that 52 cities and counties in California have 
adopted building codes to reduce their reliance on gas for building 
heating appliances, and discusses several examples.\143\ The growth in 
the number and types of local control measures to reduce pollution from 
building heating by restricting or limiting the use of natural gas-
fired heaters support their general availability as technologically 
feasible measures.
---------------------------------------------------------------------------

    \141\ Ninth Circuit Memorandum Order, 9. Regarding increased 
building electrification requirements, the Court stated that ``the 
EPA considered such an approach and reasonably accepted the State's 
determination that it was not feasible at this time.''
    \142\ See Public Justice Comment Letter, Exhibits 41 through 44.
    \143\ Heather Dadashi, Cara Horowitz, and Julia Stein, 
``Pritzker Environmental Law and Policy Briefs, How Air Districts 
Can End NOX Pollution From Household Appliances,'' Emmett 
Institute on Climate Change and the Environment, UCLA School of Law, 
March 2022, 8.
---------------------------------------------------------------------------

    Second, the time horizon of the 2012 annual PM2.5 NAAQS 
portion of the SJV PM2.5 Plan is one year later (2025 
attainment date) than that of the 2006 24-hour PM2.5 NAAQS 
portion of the Plan (2024 attainment date), affording additional time 
for potential control measures to achieve emission reductions that may 
assist attainment of the 2012 annual PM2.5 NAAQS. Even if 
full implementation of such new measures is not possible by the 
applicable attainment date, the State should evaluate whether they 
could be implemented in part, consistent with the fifth step for BACM/
BACT evaluation discussed in the PM2.5 SIP Requirements Rule 
and the General Preamble (i.e., to determine the earliest date by which 
a control measure or technology can be implemented in whole or in 
part).\144\
---------------------------------------------------------------------------

    \144\ 81 FR 58010, 58083-58085.
---------------------------------------------------------------------------

    Third, some of the underlying bases for the District's cost 
comparison for residential water heating may have changed since the 
District's 2018 adoption of the Plan. For example, in comparing 
emission reductions and cost effectiveness of low-NOX 
natural gas, propane, and electric water heaters, the District used 
data on energy factors and purchase price from Grainger Industrial 
Supply as of June 14, 2018, and lifetime energy cost data from the U.S. 
Energy Information Administration as of 2017. Furthermore, as claimed 
by Public Justice, the District did not explain its rejection of 
additional control measures of this type, other than to assert that 
they were generally more costly. Regarding residential and commercial 
space heating, CARB and the District did not provide a detailed 
economic feasibility analysis in the Plan. CARB and the District simply 
stated that, due to limited supply of certified compliant natural gas-
fired units to comply with Rule 4905, they could identify no additional 
emission reduction measures. The incomplete cost analyses presented by 
the District, changes in costs over time, and lack of justification for 
rejecting measures to reduce pollution from building heating by 
restricting or limiting the use of natural gas-fired heaters indicate 
an insufficient economic feasibility analysis.
    Fourth, CARB and at least one other air district (Bay Area AQMD) 
are moving forward in developing measures to set zero-emission 
standards for space heaters and water heaters. In developing its 2022 
State SIP Strategy (for the 2015 ozone NAAQS), CARB has stated that the 
``fuels we use and burn in buildings, primarily natural gas, for space 
and water heating contribute significantly to building-related criteria 
pollutant and GHG emissions and provide an opportunity for substantial 
emissions reductions where zero-emission technology is available.'' 
\145\ Accordingly, CARB is developing zero-emission standard concepts 
and, given the intersection of air quality needs and other areas of 
building and energy regulation, and identifying other regulatory 
entities that they plan to engage, including the U.S. Department of 
Energy, CEC, and the California Building Standards Commission, 
Department of Housing and Community Development. We note, however, that 
the proposed 2022 State SIP Strategy released August 12, 2022, 
anticipates implementation starting in 2030, pending rule development 
and CARB Board hearing in 2025.\146\
---------------------------------------------------------------------------

    \145\ CARB, ``Draft 2022 State Strategy for the State 
Implementation Plan,'' January 31, 2022, 86-88.
    \146\ CARB, ``Proposed 2022 State Strategy for the State 
Implementation Plan,'' August 12, 2022, 101-103.
---------------------------------------------------------------------------

    The Bay Area AQMD hosted public meetings in 2021 and developed 
draft amendments to certain rules that would reduce NOX 
emissions from residential and commercial furnaces and water 
heaters.\147\ Specifically, Bay Area AQMD has developed draft 
amendments to two rules: (1) Regulation 9, Rule 4 (``Nitrogen Oxides 
from Fan Type Residential Central Furnaces''), which applies to 
furnaces with a heat input rate of less than 175,000 Btu/hr and 
combination heating and cooling units with a rated cooling capacity of 
less than 65,000 Btu/hr (like SJVUAPCD Rule 4905); and (2) Regulation 
9, Rule 6 (``Nitrogen Oxides Emissions from

[[Page 60512]]

Natural Gas-Fired Boilers and Water Heaters''), which applies to water 
heaters with a rated heat input capacity of 75,000 Btu/hr or less (like 
SJVUAPCD Rule 4902), as well as additional source types and sizes.\148\
---------------------------------------------------------------------------

    \147\ A summary of the Bay Area AQMD's rule development is 
available at: https://www.baaqmd.gov/rules-and-compliance/rule-development/building-appliances.
    \148\ As in the San Joaquin Valley, larger boilers and similar 
equipment used in industrial, institutional, and large commercial 
settings are subject to other rules of the Bay Area AQMD, and 
therefore not subject to Rule 4 or Rule 6.
---------------------------------------------------------------------------

    For Rule 4, Bay Area AQMD staff have developed draft amendments to 
lower the current NOX emission limit for applicable furnaces 
from 40 nanograms of NOX per joule of useful heat (ng/j) to 
14 ng/j (which would match the limit in SJVUAPCD Rule 4905) in the 
short term (with a compliance date of January 1, 2023); followed by a 
zero-NOX emission requirement (with a compliance date of 
January 1, 2029); and expand the applicability beyond fan-type central 
furnaces to other types of equipment (e.g., wall furnaces and direct 
vent units).\149\ For Rule 6, which contains NOX limits for 
small boilers and water heaters, Bay Area AQMD staff proposes a zero-
NOX emission requirement. However, staff also note that 
while technologies achieving zero-NOX emissions exist, 
``they are limited in availability and can be expensive,'' that such 
standards would be ``technology and market-forcing,'' and, therefore, 
staff proposes compliance dates of January 1, 2027, and January 1, 
2031, depending on equipment heat rate (i.e., the size of the boiler or 
water heater).\150\
---------------------------------------------------------------------------

    \149\ Bay Area AQMD, ``Workshop Report, Draft Amendments to 
Building Appliance Rules--Regulation 9, Rule 4: Nitrogen Oxides from 
Fan Type Residential Central Furnaces and Rule 6: Nitrogen Oxide 
Emissions from Natural Gas-Fired Boilers and Water Heaters,'' 
September 2021, 1.
    \150\ Id.
---------------------------------------------------------------------------

    CARB and Bay Area AQMD efforts in this area underscore the 
importance of building heating emission sources, such as water heaters 
and space heaters (e.g., furnaces), throughout California and the 
continued effort to implement available control measures for these 
sources for criteria pollutant attainment planning requirements. At the 
same time, while SJVUAPCD, CARB, and Bay Area AQMD each acknowledge 
that zero-NOX emission technology for small residential and 
commercial space and water heating is available, it is unclear what a 
feasible implementation horizon might be in light of CARB's strategy 
and the Bay Area AQMD's draft amendments. The plan as submitted did not 
address how such implementation considerations may or may not affect 
the feasibility of setting such zero-NOX emission standards 
for space and water heating in small residential and commercial 
buildings in the SJV.
    Given the factors discussed above, we now propose that the State 
has not adequately identified potential control measures, evaluated for 
BACM/BACT, nor demonstrated the implementation of BACM/BACT for 
controlling NOX and direct PM2.5 emissions from 
building emission heating sources in the SJV.

C. Attainment Demonstration

1. Summary of 2021 Proposed Rule
    In sections IV.C (air quality modeling) and IV.F (attainment 
demonstration) of our 2021 Proposed Rule, the EPA summarized the CAA 
and regulatory requirements for air quality modeling and attainment 
demonstrations, the State's submission in the SJV PM2.5 
Plan, and our evaluation thereof.\151\ We briefly summarize those 
components herein.
---------------------------------------------------------------------------

    \151\ 86 FR 74310, 74322-74324 (air quality modeling) and 74325-
74338 (attainment demonstration).
---------------------------------------------------------------------------

    Sections 188(c)(2) and 189(b)(1)(A) of the CAA require that Serious 
area plans must include a demonstration (including air quality 
modeling) that provides for attainment of the PM2.5 NAAQS as 
expeditiously as practicable, but no later than the end of the tenth 
calendar year after the area's designation as nonattainment. The 
PM2.5 SIP Requirements Rule also specifies that the control 
strategy in a Serious area attainment plan must provide for attainment 
as expeditiously as practicable.\152\ The outermost statutory Serious 
area attainment date for the 2012 annual PM2.5 NAAQS in the 
SJV is December 31, 2025 (absent an EPA-approved attainment date 
extension request under CAA section 188(e)). For purposes of 
determining the attainment date that is as expeditious as practicable, 
the State must conduct future year modeling that takes into account 
emissions growth, known emissions controls (including any controls that 
were previously determined to be RACM/RACT or BACM/BACT), any other 
emissions controls required to meet BACM/BACT, and additional measures 
as needed for expeditious attainment of the NAAQS. The regulatory 
requirements for Serious area plans are codified at 40 CFR 51.1010 
(control strategy requirements) and 40 CFR 51.1011(b) (attainment 
demonstration and modeling requirements). We also described the EPA's 
PM2.5 modeling guidance (``Modeling Guidance''),\153\ 
including our recommendations therein for photochemical modeling, 
inputs, procedures, performance evaluation, emissions simulation, and 
calculating relative response factors (RRFs).
---------------------------------------------------------------------------

    \152\ 40 CFR 51.1011(b)(1); 81 FR 58010, 58087.
    \153\ Memorandum dated November 29, 2018, from Richard Wayland, 
Air Quality Assessment Division, OAQPS, EPA, to Regional Air 
Division Directors, EPA, Subject: ``Modeling Guidance for 
Demonstrating Air Quality Goals for Ozone, PM2.5, and 
Regional Haze,'' (``Modeling Guidance'').
---------------------------------------------------------------------------

    With respect to air quality modeling, the 2018 PM2.5 
Plan included the State's modeled attainment demonstration projecting 
that the SJV will attain the 2012 annual PM2.5 NAAQS by 
December 31, 2025; the State's primary discussion of the photochemical 
modeling appears in Appendix K (``Modeling Attainment Demonstration''). 
The State provides a conceptual model of PM2.5 formation in 
the SJV as part of the modeling protocol in Appendix L (``Modeling 
Protocol'') and describes emission input preparation procedures. The 
State presents additional relevant information in Appendix C (``Weight 
of Evidence Analysis'') of CARB's staff report for the 2018 
PM2.5 Plan,\154\ which includes ambient trends and other 
data in support of the demonstration of attainment by 2025.
---------------------------------------------------------------------------

    \154\ CARB, ``Staff Report, Review of the San Joaquin Valley 
2018 Plan for the 1997, 2006, and 2012 PM2.5 Standards,'' 
release date December 21, 2018 (``CARB Staff Report'').
---------------------------------------------------------------------------

    In the 2021 Proposed Rule, the EPA presented its review of the 
State's modeling approach and its many interconnected facets, including 
model input preparation, model performance evaluation, use of the model 
output for the numerical NAAQS attainment test, and modeling 
documentation, and found it to be generally consistent with the EPA's 
recommendations in the Modeling Guidance. We incorporated our 
evaluation of the Plan's modeling for the 2006 24-hour PM2.5 
NAAQS portion of the SJV PM2.5 Plan \155\ and extended that 
evaluation with information specific to the 2012 annual 
PM2.5 NAAQS. Overall, in the 2021 Proposed Rule, we 
considered the State's analyses consistent with the EPA's guidance on 
modeling for PM2.5 attainment planning purposes and proposed 
to find that the modeling in the 2018 PM2.5 Plan was 
adequate for the purposes of supporting the State's RFP demonstration 
and the attainment demonstration.
---------------------------------------------------------------------------

    \155\ EPA Region IX, ``Technical Support Document, EPA 
Evaluation of Air Quality Modeling, San Joaquin Valley 
PM2.5 Plan for the 2006 PM2.5 NAAQS,'' 
February 2020 (``EPA's 2006 NAAQS Modeling TSD'').
---------------------------------------------------------------------------

    With respect to the attainment demonstration, the SJV 
PM2.5 Plan includes a modeled demonstration projecting 
attainment of the 2012 annual PM2.5 NAAQS in the SJV by 
December 31, 2025, based on emission reductions

[[Page 60513]]

from implementation of baseline control measures and the development, 
adoption, and implementation of additional control measures to meet 
specific enforceable commitments. In the EPA's 2021 Proposed Rule, we 
described how the Plan's control strategy was to reduce emissions from 
sources of NOX and direct PM2.5 and that most of 
the projected emission reductions are achieved by baseline measures--
i.e., the combination of State and District measures adopted prior to 
the State's and District's adoption of the Plan--that will achieve 
ongoing emission reductions from the 2013 base year to the 2025 
projected attainment year.
    The remainder of the Plan's emission reductions are to be achieved 
by additional measures to meet enforceable commitments, including 
potential regulatory and incentive-based measures and, as necessary, 
substitute measures.\156\ In the Valley State SIP Strategy and the 2018 
PM2.5 Plan, CARB and the District, respectively, included 
commitments to take action on specific measures by specific years or to 
develop substitute measures (referred to as ``control measure 
commitments'') and to achieve specified amounts of NOX and 
direct PM2.5 emission reductions by certain dates (referred 
to as ``aggregate tonnage commitments'').\157\ We refer to these 
complementary commitments herein as ``aggregate commitments.''
---------------------------------------------------------------------------

    \156\ In this proposed rule, the term ``substitute measures'' 
means additional control measures that were not identified in CARB 
and the District's original control measure commitments in adopting 
the Valley State SIP Strategy and the 2018 PM2.5 Plan, 
respectively. The ``substitute'' aspect primarily relates to 
emission reductions (i.e., providing emission reductions where any 
adopted measure achieves less emission reductions than originally 
estimated, and/or providing emission reductions in lieu of any 
originally planned measure that is not adopted). They are also 
sometimes referred to as ``alternative measures'' in the SJV 
PM2.5 Plan and adopting resolutions.
    \157\ CARB Resolution 18-49 and SJVUAPCD Governing Board 
Resolution 18-11-16, paragraph 6.
---------------------------------------------------------------------------

    In the 2021 Proposed Rule, the EPA described several findings 
relating to our evaluation of the SJV PM2.5 Plan's 
attainment demonstration. First, we proposed to approve the Plan's 
emissions inventories and to find the Plan's air quality modeling 
adequate.\158\ Second, we proposed to find that the Plan provides for 
expeditious attainment through the timely implementation of the control 
strategy to reduce emissions from sources of NOX and direct 
PM2.5, including RACM, BACM, and any other emission controls 
necessary for expeditious attainment.
---------------------------------------------------------------------------

    \158\ Sections IV.A (emissions inventory) and IV.C (air quality 
modeling) of the 2021 Proposed Rule.
---------------------------------------------------------------------------

    Third, the EPA proposed to find that the emissions reductions that 
are relied on for attainment in the SIP submission are creditable. We 
noted that the SJV PM2.5 Plan relies principally on already 
adopted and approved rules to achieve the emissions reductions needed 
to attain the 2012 annual PM2.5 NAAQS in the SJV by December 
31, 2025, and that the balance of the reductions that the State has 
modeled to achieve attainment by this date is currently represented by 
enforceable commitments that account for 13.8% of the NOX 
and 8.0% of the direct PM2.5 emissions reductions needed for 
attainment. In terms of our evaluation of CARB and the District's 
enforceable commitments, we proposed to find that circumstances in the 
SJV for the 2012 annual PM2.5 NAAQS warrant the 
consideration of enforceable commitments and that the EPA's three 
criteria for such commitments had been met: (1) the commitments 
constitute a limited portion of the required emissions reductions; (2) 
both CARB and the District have demonstrated their capability to meet 
their commitments; and (3) the commitments are for an appropriate 
timeframe. We therefore proposed to approve the State's reliance on 
these enforceable commitments in its attainment demonstration.
    Overall, in the 2021 Proposed Rule, we proposed to approve the SJV 
PM2.5 Plan's demonstration of attainment of the 2012 annual 
PM2.5 NAAQS by December 31, 2025, consistent with the 
requirements of CAA section 189(b)(1)(A). We presented the basis for 
our proposed determination in sections IV.F.3.a through IV.F.3.e of the 
2021 Proposed Rule and provided further detail of our evaluation of 
baseline measures and the additional measures and aggregate commitments 
in sections II and IV, respectively, of the EPA's 2012 Annual 
PM2.5 TSD.
2. Summary of Ninth Circuit Order and Adverse Comments
    As introduced in section I.D of this proposed rule, in response to 
a petition for review of the EPA's approval of the 2006 24-hour 
PM2.5 NAAQS portion of the SJV PM2.5 Plan, the 
Ninth Circuit Court of Appeals issued a Memorandum Opinion that, in 
part, vacated the final action with respect the EPA's second factor for 
evaluating the validity of the State's enforceable commitments (i.e., 
whether the State is capable of fulfilling its commitment). The Ninth 
Circuit's order is very relevant to this proposed rule because the 
State relied on the same common control strategy, including the same 
set of enforceable commitments (i.e., the same set of control measure 
commitments and aggregate tonnage commitments) for both the 2006 24-
hour PM2.5 NAAQS Serious area plan and the 2012 annual 
PM2.5 NAAQS Serious area plan.
    The Ninth Circuit found that the EPA ``fail[ed] to provide evidence 
or a reasoned explanation for its conclusion that California will be 
able to fulfill its commitment'' in the face of a potential multi-
billion dollar funding shortfall for incentive-based control measure 
commitments, ``which could result in emission reduction shortfalls of 
approximately 7% of the total NOX reductions and 8% of the 
total PM2.5 reductions necessary for attainment.'' \159\ In 
response to the EPA's arguments that: (1) the funding shortfall may be 
smaller than projected; (2) emission reductions may be less expensive 
than the strategy predicts; (3) certain yet-to-be-quantified sources of 
reductions in the Plan may make up for shortfalls; and (4) California 
and the District may identify other measures to fulfill their 
commitments, the Court wrote that, ``[b]ecause these speculative 
assertions are unsupported by the evidence, they fail to ensure that 
California and the District have a plausible strategy for achieving 
this portion of the attainment strategy, and therefore do not 
collectively satisfy the second factor of the EPA's three-factor 
test.'' \160\ It is important to emphasize that the State relied 
heavily on the projected emission reductions that it hopes to achieve 
through new control measures and emissions reductions reflected in the 
aggregate commitments. These reductions are crucial to the State 
meeting the modeled attainment demonstration and RFP requirements. If 
it is not credible that the State can meet the commitments, then the 
EPA cannot approve other nonattainment plan elements that rely upon 
them.
---------------------------------------------------------------------------

    \159\ Medical Advocates for Healthy Air v. EPA, Case No. 20-
72780, Dkt. #58-1 (9th Cir., April 13, 2022), 6.
    \160\ Id. at 7.
---------------------------------------------------------------------------

    Separately, in comments on the EPA's 2021 Proposed Rule, Public 
Justice states that CARB and the District's aggregate tonnage 
commitments are to ``achieve a specific amount of reductions at the 
last possible moment prior to the attainment deadline with no concrete 
strategies for how that will be achieved.'' \161\ They assert that 
prior plans with aggregate tonnage commitments for the 1997 annual 
PM2.5 NAAQS by 2015 (i.e., the 2008 PM2.5 Plan) 
and then by 2020 (i.e., the SJV PM2.5 Plan) failed to attain 
those standards and that such past failures implies that the 
commitments failed to

[[Page 60514]]

deliver the promised clean air.\162\ The commenters further state that 
``deferred, unspecified, and last-minute promises to achieve reductions 
(i.e., aggregate commitments), inflicts disparate impacts in violation 
of Title VI,'' irrespective of whether the commitments comply with the 
CAA.
---------------------------------------------------------------------------

    \161\ Public Justice Comment Letter, 20.
    \162\ Public Justice refers specifically to the EPA's November 
2016 finding of failure to attain and the EPA's November 2021 final 
disapproval of the 1997 annual PM2.5 NAAQS portion of the 
SJV PM2.5 Plan. 81 FR 84481 (November 23, 2016) and 86 FR 
67329 (November 26, 2021), respectively.
---------------------------------------------------------------------------

3. The EPA's Reconsidered Proposal
    As a result of the Ninth Circuit Memorandum Opinion with respect to 
the SJV PM2.5 Plan's enforceable commitments, the EPA has 
reconsidered its proposed approval of the Plan's demonstration of 
attainment for the 2012 annual PM2.5 NAAQS in the SJV by 
December 31, 2025, and now proposes to disapprove the Plan's attainment 
demonstration. The Ninth Circuit Memorandum Opinion raised concerns 
about the ability of CARB and the District to fulfill the commitments.
    We present our reconsideration in the following sections of this 
proposed rule: (1) our reconsideration of CARB and the District's 
enforceable commitments and proposal that the commitments do not meet 
the second factor of the EPA's three-factor test (in section II.C.3.a); 
and (2) the effect of our proposed disapproval of the State's 
enforceable commitments and specific portions of the State's BACM 
demonstration on the modeled attainment demonstration (in section 
II.C.3.b).
a. Additional Measures and Enforceable Commitments
    In this subsection we re-examine CARB and the District's 
enforceable commitments. We describe CARB and the District's progress 
in adopting specific measures that they committed to present for 
governing board adoption, and evaluate whether CARB and the District 
have demonstrated the capability to achieve specific tonnages of 
reductions that they committed to achieve by the 2025 attainment year. 
We first enumerate the measures that have already been approved into 
the SIP and quantify the amount of the tonnage commitment that these 
account for. We then calculate CARB and the District's remaining 
commitments as of the time of this notice, describe the strategy that 
CARB and the District have provided for achieving the remaining 
reductions (consisting of submitted measures that have not yet been 
approved into the SIP, adopted measures that have not yet been 
submitted to the EPA, measures under development, and other potential 
future measures), and calculate the reductions that may be associated 
with these measures. We conclude that although CARB and the District 
have made substantial progress toward achieving the committed-to 
reductions, CARB and the District have not presented a plausible 
strategy demonstrating that they are capable of achieving the entirety 
of the aggregate commitment.
    In our 2021 Proposed Rule, the EPA described the SJV 
PM2.5 Plan's series of CARB and District commitments to 
achieve emission reductions through additional control measures, beyond 
baseline measures, that are intended to contribute to expeditious 
attainment of the 2012 annual PM2.5 NAAQS. For mobile 
sources, CARB identified a list of 12 State regulatory measures and 3 
incentive-based measures that CARB has committed to propose to its 
Board for consideration by specific years.\163\ For stationary sources, 
the District identified a list of nine regulatory measures and three 
incentive-based measures that the District has committed to propose to 
its Board for consideration by specific years.\164\
---------------------------------------------------------------------------

    \163\ CARB Resolution 18-49, Attachment A and Valley State SIP 
Strategy, Table 7 (``State Measures and Schedule for the San Joaquin 
Valley''). The schedule of proposed SIP measures in Table 7 includes 
two additional CARB measures: the second phase of the Advanced Clean 
Cars Program (``ACC 2'') and the ``Cleaner In-Use Agricultural 
Equipment'' measures. However, these measures are not scheduled for 
implementation until 2026 and 2030, respectively, which is after the 
January 1, 2025 implementation deadline under 40 CFR 51.1011(b)(5) 
for control measures necessary for attainment by December 31, 2025. 
Therefore, we are not reviewing these measures as part of the 
control strategy to attain the 2012 annual PM2.5 NAAQS in 
the SJV.
    \164\ SJVUAPCD Governing Board Resolution 18-11-16 and 2018 
PM2.5 Plan, Table 4-4 (``Proposed Regulatory Measures'') 
and Table 4-5 (``Proposed Incentive-Based Measures'').
---------------------------------------------------------------------------

    The Plan contains CARB's and the District's estimates of the 
emission reductions that could be achieved by each of these additional 
measures, if adopted as planned.\165\ As we described in our 2021 
Proposed Rule, CARB's commitments are contained in CARB Resolution 18-
49 (October 25, 2018) and the Valley State SIP Strategy and consist of 
two parts: a control measure commitment and a tonnage commitment.
---------------------------------------------------------------------------

    \165\ 2018 PM2.5 Plan, Ch. 4, Table 4-3 (''Emission 
Reductions from District Measures'') and Table 4-9 (''San Joaquin 
Valley Expected Emission Reductions from State Measures'') and 
Valley State SIP Strategy, Table 8 (``San Joaquin Valley Expected 
Emission Reductions from State Measures'').
---------------------------------------------------------------------------

    First, CARB has committed to ``begin the measure's public process 
and bring to the Board for consideration the list of proposed SIP 
measures outlined in the Valley State SIP Strategy and included in 
Attachment A, according to the schedule set forth.'' \166\ By email 
dated November 12, 2019, CARB confirmed that it intended to begin the 
public process on each measure by discussing the proposed regulation or 
program at a public meeting (workshop, working group, or Board hearing) 
or in a publicly-released document, and to then propose the regulation 
or program to its Board.\167\ Second, CARB has committed ``to achieve 
the aggregate emissions reductions outlined in the Valley State SIP 
Strategy of 32 tpd of NOX and 0.9 tpd of PM2.5 
emissions reductions in the San Joaquin Valley by 2024 and 2025.'' 
\168\ The Valley State SIP Strategy explains that CARB's overall 
commitment is to ``achieve the total emission reductions necessary to 
attain the Federal air quality standards, reflecting the combined 
reductions from the existing control strategy and new measures'' and 
that ``if a particular measure does not get its expected emissions 
reductions, the State is still committed to achieving the total 
aggregate emission reductions.'' \169\
---------------------------------------------------------------------------

    \166\ CARB Resolution 18-49, 5.
    \167\ Email dated November 12, 2019, from Sylvia Vanderspek, 
CARB, to Anita Lee, EPA Region IX, ``RE: SJV PM2.5 
information'' (attaching ``Valley State SIP Strategy Progress'') and 
CARB Staff Report, 14.
    \168\ CARB Resolution 18-49, 5.
    \169\ Valley State SIP Strategy, 7.
---------------------------------------------------------------------------

    Similarly, in our 2021 Proposed Rule, we explained that the 
District's commitments are contained in SJVUAPCD Governing Board 
Resolution 18-11-16 (November 15, 2018) and Chapter 4 of the 2018 
PM2.5 Plan and also consist of two parts: a control measure 
commitment and a tonnage commitment. First, the District has committed 
to ``take action on the rules and measures committed to in Chapter 4 of 
the Plan by the dates specified therein, and to submit these rules and 
measures, as appropriate, to CARB within 30 days of adoption for 
transmittal to EPA as a revision to the [SIP].'' \170\ By email dated 
November 12, 2019, the District confirmed that it intended to take 
action on the listed rules and measures by beginning the public process 
on each measure, i.e., discussing the proposed regulation or program at 
a public meeting, including a workshop, working group, or Board 
hearing, or in a publicly-released document, and then proposing the 
rule or measure to the SJVUAPCD Governing Board.\171\ Second, the 
District has

[[Page 60515]]

committed to ``achieve the aggregate emissions reductions of 1.88 tpd 
of NOX and 1.3 tpd of PM2.5 by 2024/2025'' 
through adoption and implementation of these measures or, if the total 
emission reductions from these rules or measures are less than these 
amounts, ``to adopt, submit, and implement substitute rules and 
measures that achieve equivalent reductions in emissions of direct 
PM2.5 or PM2.5 precursors'' in the same 
implementation timeframes.\172\
---------------------------------------------------------------------------

    \170\ SJVUAPCD Governing Board Resolution 18-11-16, 10-11.
    \171\ Email dated November 12, 2019, from Jon Klassen, SJVUAPCD, 
to Wienke Tax, EPA Region IX, ``RE: follow up on aggregate 
commitments in SJV PM2.5 Plan'' (attaching ``District 
Progress in Implementing Commitments with 2018 PM2.5 
Plan'').
    \172\ SJVUAPCD Governing Board Resolution 18-11-16, 10-11.
---------------------------------------------------------------------------

    In sections IV.F.3.c and IV.F.3.d of our 2021 Proposed Rule, the 
EPA described CARB's and the District's progress as of that point in 
time on their control measure commitments and progress towards 
fulfilling their respective aggregate commitments, respectively. Based 
on our reconsideration of the State's enforceable commitments in light 
of the Ninth Circuit Memorandum Opinion, while we propose to retain 
certain findings with respect to the State's progress, we now propose 
that the State has not adequately demonstrated that it can fulfill the 
remaining portions of its enforceable commitments (i.e., the second 
factor of the EPA's three-factor test). We present our reconsidered 
evaluation of the status of CARB's and the District's control strategy 
and our three-factor test for enforceable commitments, as follows.
    With respect to progress on the control measure commitments, CARB 
and the District together have adopted 18 measures of the 27 control 
measure commitments in the SJV PM2.5 Plan and have begun the 
public process on 5 of the remaining control measure commitments, which 
is unchanged since the time of our 2021 Proposed Rule. This progress is 
described in further detail in CARB and the District's ``Progress 
Report and Technical Submittal for the 2012 PM2.5 Standard 
San Joaquin Valley'' (2021 Progress Report).\173\ For CARB's portion, 
CARB has adopted 10 of the 15 measures identified in its commitment 
(including one incentive-based measure) and begun the public process on 
3 of the remaining 5 measures. For the District's portion of the 
control measure commitments, the District has adopted 8 of the 12 
measures identified in its commitment (including one incentive-based 
measure) and begun the public process on 2 of the remaining 4 measures.
---------------------------------------------------------------------------

    \173\ ``Progress Report and Technical Submittal for the 2012 
PM2.5 Standard San Joaquin Valley,'' October 19, 2021. 
Transmitted to the EPA by letter dated October 20, 2021, from 
Richard W. Corey, Executive Officer, CARB, to Deborah Jordan, Acting 
Regional Administrator, EPA Region IX. See sections of 2021 Progress 
Report entitled ``Progress in Implementing District Measures'' and 
``Progress in Implementing CARB Measures.''
---------------------------------------------------------------------------

    Although CARB and the District have made substantial progress in 
developing and adopting the regulatory measures listed in their 
respective control measure commitments, they have not yet fulfilled the 
commitments for several measures in accordance with the timeframes 
established in the SJV PM2.5 Plan. We provide further detail 
on CARB and the District's control measure commitments in section IV.A 
of the EPA's 2012 Annual PM2.5 TSD (including tables IV-A 
and IV-B regarding CARB and the District's control measure commitments, 
respectively).\174\
---------------------------------------------------------------------------

    \174\ We note that Table IV-A of the EPA's 2012 Annual 
PM2.5 TSD contained an error with respect to the adoption 
date of CARB's measure for Transportation Refrigeration Units Used 
for Cold Storage. While CARB had heard proposed amendments to the 
measure on September 23, 2021, the measure was not actually adopted 
until February 24, 2022, following further process and rule 
adjustments required by the Board. CARB Resolution 22-5, February 
24, 2022.
---------------------------------------------------------------------------

    Regarding the remaining nine measures not yet proposed for board 
consideration, we continue to note that one measure, Rule 4550 
(``Conservation Management Practices''), has an action year of 2022 in 
the 2018 PM2.5 Plan (i.e., the District has the remainder of 
2022 to present a proposed measure for board consideration) and that 
four regulatory measures and four incentive-based measures are overdue. 
For the four regulatory measures, while CARB and the District have not 
proposed these measures to their respective boards, they began the 
public process on each of the four measures on time with respect to the 
schedule of their respective public process commitments. To our 
knowledge, CARB anticipates board consideration of the diesel fuel 
measures in 2022 and the forklift measure in 2022 or 2023 \175\ and 
continues to develop the airport ground support equipment measure; the 
District continues to evaluate potential amendments to Rule 4692 in the 
near future.\176\
---------------------------------------------------------------------------

    \175\ In the 2021 Progress Report (dated October 19, 2021), page 
20, CARB indicates that the Zero-Emission Off-Road Forklift 
Regulation Phase 1 would be presented for Board consideration ``as 
early as 2022,'' while CARB's updated ``SJV PM2.5 SIP 
Measure Tracking'' (dated December 2021) anticipates presenting the 
measure to the Board in Summer 2023.
    \176\ 2021 Progress Report, 8-9, 20-22, and tables 2 and 3.
---------------------------------------------------------------------------

    For the four incentive-based measures, CARB and the District 
continue to invest in reducing emissions from heavy-duty trucks and 
buses, off-road equipment, agricultural operation internal combustion 
engines, and commercial under-fired charbroiling.\177\ However, while 
CARB and the District have discussed the proposed programs at board 
hearings,\178\ to our knowledge, CARB and the District have not started 
the public process for the four incentive-based control measure 
commitments as enforceable measures to be submitted to the EPA for 
approval and inclusion as control measures in the California SIP. 
Furthermore, as discussed in section IV.F.3.c of our 2021 Proposed 
Rule, for heavy-duty trucks and off-road equipment, CARB acknowledges 
that many of the project lives do not span the attainment year \179\ 
and, thus, while these projects may accelerate emission reductions and 
benefit communities in the SJV, the projects that qualify for SIP 
credit may be limited for the purposes of the 2012 annual 
PM2.5 NAAQS Serious area attainment demonstration.
---------------------------------------------------------------------------

    \177\ CARB, ``Long-Term Heavy-Duty Investment Strategy, 
Including Fiscal Year 2020-21 Three-Year Recommendations for Low 
Carbon Transportation Investments,'' (App. D to CARB's ``Proposed 
Fiscal Year 2021-22 Funding Plan for Clean Transportation 
Incentives''), release date October 8, 2021; and SJVUAPCD, 
``Comprehensive Annual Financial Report, Fiscal Year Ended June 30, 
2020,'' release date December 23, 2020. See also, 2021 Progress 
Report, 3 and 15.
    \178\ For example, CARB staff discussed the Accelerated Turnover 
of Trucks and Buses Incentive Measure at its annual 2020 update to 
the CARB Board. CARB presentation, ``Update on the 2018 
PM2.5 SIP for the San Joaquin Valley,'' October 22, 2020. 
District staff discussed and adopted an emission reductions strategy 
for commercial under-fired charbroiling, including incentives, in 
December 2020. SJVUAPCD, ``Item Number 11: Adopt Proposed Commercial 
Under-Fired Charbroiling Emission Reduction Strategy,'' December 17, 
2020.
    \179\ Id. at 24 and 32. Generally, mobile source incentive 
projects implemented under the Carl Moyer program are under contract 
only during the ``project life'' and may not be credited with SIP 
emission reductions after the project life ends. EPA Region IX, 
``Technical Support Document for EPA's Rulemaking for the California 
State Implementation Plan California Air Resources Board Resolution 
19-26 San Joaquin Valley Agricultural Equipment Incentive Measure,'' 
February 2020, 12-13.
---------------------------------------------------------------------------

    Overall, while CARB and the District have made substantial progress 
in developing and adopting the regulatory measures listed in their 
respective control measure commitments that were submitted in the SJV 
PM2.5 Plan, in light of the Ninth Circuit Memorandum 
Opinion, we have reconsidered the effect of the eight overdue measures 
of the original commitments and in particular the overdue incentive-
based measures, on our evaluation of CARB and the District's aggregate 
tonnage commitments and our three-factor test. Under the second factor 
of the EPA's test for enforceable commitments, the

[[Page 60516]]

Agency must evaluate whether a State is capable of fulfilling such 
commitments. The tardiness of presenting these control measures for 
board consideration renders the reductions from these measures more 
speculative under the second factor.
    With respect to the aggregate tonnage commitments to attain the 
2012 annual PM2.5 NAAQS in the SJV, we reiterate that CARB 
committed to achieve 32 tpd of NOX and 0.9 tpd of 
PM2.5 emissions reductions, and the District committed to 
achieve 1.88 tpd of NOX and 1.3 tpd of PM2.5 
emissions reductions by 2025. These aggregate tonnage commitments sum 
to 33.88 tpd NOX and 2.2 tpd direct PM2.5. CARB 
and the District have committed to achieve these reductions via the 27 
control measure commitments, or such other substitute measures as may 
be necessary, to achieve the aggregate tonnage commitments for 
NOX and direct PM2.5.
    For the purpose of our analysis of the State's progress toward 
achieving its aggregate tonnage commitments, of the 18 measures adopted 
by December 2021, as well as the adoption of an important substitute 
measure (the Agricultural Burning Phase-out Measure \180\), the State 
has submitted 12 measures as revisions to the California SIP (i.e., 
more than the 9 measures submitted to EPA as of the time of the 2021 
Proposed Rule). Since December 2021, the EPA finalized or proposed 
approval of three control measure SIP submissions that were control 
measure commitments in the SJV PM2.5 Plan.
---------------------------------------------------------------------------

    \180\ See 87 FR 36222 (June 16, 2022).
---------------------------------------------------------------------------

    First, the EPA finalized approval of the Heavy-Duty Vehicle 
Inspection Program (HDVIP) and Periodic Smoke Inspection Program 
(PSIP).\181\ However, as in our 2021 Proposed Rule, CARB has not yet 
provided its analysis of the basis for this emission reduction estimate 
(of 0.02 tpd direct PM2.5, per the State's 2021 Progress 
Report). Therefore, the EPA is not proposing at this time to credit 
this measure with any particular amount of emission reductions towards 
attainment of the 2012 annual PM2.5 NAAQS in the SJV.
---------------------------------------------------------------------------

    \181\ 87 FR 27949 (May 10, 2022).
---------------------------------------------------------------------------

    Second, the EPA finalized approval of the Agricultural Burning 
Phase-out Measure,\182\ which includes a schedule to phase-out (i.e., 
introduce prohibitions of) agricultural burning for additional crop 
categories or materials accounting for a vast majority of the tonnage 
of agricultural waste in phases that started January 1, 2022, and 
become fully implemented by January 1, 2025.\183\ The EPA received 
comments from the District that supported approval of the Agricultural 
Burning Phase-out Measure into the SIP while also advocating for a 
higher rule effectiveness rate (i.e., 95% instead of EPA's proposed 
80%),\184\ which in turn would increase the amount of emission 
reductions that the EPA would credit towards fulfilling the District's 
aggregate tonnage commitment. We continue to evaluate these comments 
and for now have retained our proposal to credit the measure for 
emission reductions of 0.83 tpd NOX and 1.23 tpd direct 
PM2.5, consistent with the 80% rule effectiveness rate used 
by the EPA in the 2021 Proposed Rule.
---------------------------------------------------------------------------

    \182\ 87 FR 36222.
    \183\ SJVUAPCD, ``Supplemental Report and Recommendations on 
Agricultural Burning,'' June 17, 2021 (``2021 Supplemental 
Report''), including Table 2-1 (``Accelerated Reductions by Crop 
Category'').
    \184\ Letter dated January 25, 2022, from Jonathan Klassen, 
Director of Air Quality Science and Planning, SJVUPACD, to Michael 
Regan, Administrator, U.S. EPA.
---------------------------------------------------------------------------

    Third, the EPA has proposed approval of Rule 4311 (``Flares''), as 
amended December 17, 2020.\185\ The District's staff report for Rule 
4311 estimates that the emission reductions from these amendments would 
be 0.19 tpd NOX and 0.03 tpd direct PM2.5 in 
2025.\186\ The EPA continues to evaluate the District's estimate with 
respect to SIP-creditable emission reductions, though we note that they 
are relatively small when compared to the overall 207.38 tpd 
NOX and 6.4 tpd direct PM2.5 modeled to attain 
the 2012 PM2.5 NAAQS and to the combined aggregate tonnage 
commitments of 33.88 tpd NOX and 2.2 tpd direct 
PM2.5.
---------------------------------------------------------------------------

    \185\ 87 FR 3736 (January 25, 2022).
    \186\ SJVUAPCD, ``Item Number 12: Adopt Proposed Amendments to 
Rule 4311 (Flares),'' December 17, 2020, Attachment C (``Final Draft 
Staff Report with Appendices for Proposed Amendments to Rule 
4311''), 21-22.
---------------------------------------------------------------------------

    Similar to our 2021 Proposed Rule, we propose to credit reductions 
from three measures, all of which are now approved into the SIP and 
have large associated emission reductions of direct PM2.5 
and/or NOX in the SJV.\187\ The three measures are: Rule 
4901 (``Wood Burning Fireplaces and Wood Burning Heaters''); two of 
three parts of the Agricultural Equipment Incentive Measure (for which 
we described our proposed SIP credit in the 2021 Proposed Rule); and 
the Agricultural Burning Phase-out Measure (for which we described our 
proposed SIP credit in this proposed rule).\188\
---------------------------------------------------------------------------

    \187\ The seven additional measures submitted as SIP revisions 
for which the EPA has not proposed action as of August 2022 include: 
the Innovative Clean Transit measure (submitted February 13, 2020); 
Rules 4306 and 4320 (submitted March 12, 2021); Rule 4702 (submitted 
October 15, 2021); Rules 4352 and 4354 (submitted March 9, 2022), 
and the Residential Wood Burning Incentive Measure (submitted March 
17, 2022).
    \188\ Final actions on these measures are as follows: 85 FR 
44206 (July 22, 2020) (Rule 4901), 86 FR 73106 (December 27, 2021) 
(Agricultural Equipment Incentive Measure), and 87 FR 36222 (June 
16, 2022) (Agricultural Burning Phase-out Measure).
---------------------------------------------------------------------------

    Based on these SIP-approved measures, our estimate of the remaining 
aggregate tonnage commitments remains the same as in our 2021 Proposed 
Rule. Specifically, in Table 1 herein we summarize the total 
NOX and direct PM2.5 emission reductions that the 
State models as sufficient to attain the 2012 annual PM2.5 
NAAQS in the SJV by December 31, 2025, the emission reductions 
attributed to baseline measures and new control strategy measures 
(including only measures currently approved into the California SIP), 
and the emission reductions remaining as aggregate tonnage commitments.

    Table 1--Reductions for Attainment in 2025 and Aggregate Tonnage
                               Commitments
------------------------------------------------------------------------
                                                           Direct PM2.5
                                            NOX  (tpd)         (tpd)
 
------------------------------------------------------------------------
A................  Total reductions from          207.38             6.4
                    baseline and control
                    strategy measures
                    modeled to achieve
                    attainment.
B................  Reductions from                 173.5             4.2
                    baseline measures.
C................  Reductions from                  5.29            1.69
                    additional measures
                    approved into the
                    California SIP.
D................  Total reductions                28.59            0.51
                    remaining as
                    commitments (A-B-C).
E................  Percent of total                13.8%            8.0%
                    reductions needed
                    remaining as
                    commitments (D/A).
------------------------------------------------------------------------
Sources: 2018 PM2.5 Plan, Ch. 4, tables 4-3 and 4-7, and Appendix B,
  tables B-1 and B-2.

[[Page 60517]]

    As shown in Table 1, 13.8% of the NOX reductions 
necessary for attainment and 8.0% of the direct PM2.5 
reductions necessary for attainment remain as aggregate tonnage 
commitments (i.e., combining CARB and the District's remaining 
commitments).\189\ Based on the direct PM2.5 emission 
reductions that the EPA has credited to Rule 4901 (0.2 tpd) and the 
Agricultural Burning Phase-out Measure (1.23 tpd), which add up to 1.43 
tpd, we conclude that the District has exceeded its 1.3 tpd direct 
PM2.5 commitment by 0.13 tpd.
---------------------------------------------------------------------------

    \189\ However, we note that if the EPA were to grant maximum 
credit for the emission reductions calculated by the District for 
Rule 4311 (0.19 tpd NOX and 0.03 tpd direct 
PM2.5), the remaining aggregate tonnage commitments would 
be 28.4 tpd NOX (13.7% of total reductions needed to 
attain in 2025) and 0.48 tpd direct PM2.5 (7.5% of total 
reductions needed to attain in 2025).
---------------------------------------------------------------------------

    Beyond the measures that the EPA has taken final action to approve 
into the California SIP and proposed to credit herein, CARB has 
provided updated emission reduction estimates for 10 additional 
measures, including 9 that have been adopted, as well as one substitute 
measure in development, as described in the 2021 Progress Report. The 
CARB measure with the largest updated emission reduction estimates is 
the Heavy-Duty Vehicle Inspection and Maintenance Program (``Heavy-Duty 
I/M'').
    The District has similarly provided updated emission reduction 
estimates for seven additional measures, including six that have been 
adopted. The District measures with the largest updated emission 
reduction estimates include amendments to Rule 4702 (``Internal 
Combustion Engines'') (0.61 tpd NOX), the Residential Wood 
Burning Devices Incentive Projects measure (0.33 tpd direct 
PM2.5), and Rule 4354 (``Glass Melting Furnaces'') (0.5 tpd 
NOX and 0.04 tpd direct PM2.5), as well as 
amendments planned in 2022 to Rule 4550 (``Conservation Management 
Practices'') (0.32 tpd direct PM2.5).
    The EPA is not proposing to credit towards the aggregate tonnage 
commitments the updated emission reduction estimates from these 
additional District measures. We will review and act on the CARB and 
District measures submitted to date (Innovative Clean Transit, Rule 
4306, Rule 4320, Rule 4702, Rule 4352, Rule 4354, and the Residential 
Wood Burning Incentive Measure), as well as future measure submissions, 
in separate rulemakings, during which time the public will have an 
opportunity to review and provide comment.
    Although we are not proposing to credit reductions from these 
measures at this time, in order to determine whether CARB and District 
have the capability to meet their aggregate tonnage commitments, we 
have re-evaluated the updated emission reduction estimates to assess 
whether they could meet the NOX and/or direct 
PM2.5 emission reduction commitments with these measures or, 
if not, how much would remain of CARB and the District's unfulfilled 
aggregate tonnage commitments.

 Table 2--Hypothetical Emission Reductions From Estimated, Adopted, and/
   or Submitted Additional Measures and Effect on Remaining Aggregate
                      Tonnage Commitments for 2025
------------------------------------------------------------------------
                                                           Direct PM2.5
                                            NOX  (tpd)         (tpd)
 
------------------------------------------------------------------------
A................  Total reductions               207.38             6.4
                    needed from baseline
                    and control strategy
                    measures (see Table
                    1, row A of this
                    proposed rule).
B................  Total reductions                28.59            0.51
                    remaining as
                    commitments after
                    SIP credit (see
                    Table 1, row D of
                    this proposed rule).
                   CARB:
                   Submitted Measures:
                       HDVIP and PSIP                  0            0.02
                        \a\.
                       Innovative Clean            0.017          <<0.01
                        Transit.
                                         -------------------------------
C................        Sub-Total......           0.017            0.02
                   Additional Adopted
                    Measures:
                       Heavy-Duty I/M...            14.7            0.03
                       Amended Warranty             0.34          <<0.01
                        Requirements for
                        Heavy-Duty
                        Vehicles.
                       Heavy-Duty Low-                 0               0
                        NOX Engine
                        Standard--Califo
                        rnia Action.
                       Advanced Clean               0.08          <<0.01
                        Local Trucks
                        (Last Mile
                        Delivery).
                       Zero-Emission              <<0.01          <<0.01
                        Airport Shuttle
                        Buses.
                       Small Off-Road              0.155           0.007
                        Engines.
                       Transport                    0.04            0.01
                        Refrigeration
                        Units Used for
                        Cold Storage.
                       Agricultural                 0.64            0.04
                        Equipment
                        Incentive
                        Measure-Phase 1
                        (NRCS portion).
                                         -------------------------------
                       Agricultural                  4.9             0.5
                        Equipment
                        Incentive
                        Measure Phase 2.
                                         -------------------------------
D................        Sub-Total......          15.955           0.087
                   Measures Not Yet
                    Presented for Board
                    Consideration: \b\
                       Zero-Emission Off-           0.02          <<0.01
                        Road Forklift
                        Regulation Phase
                        1.
                       Agricultural                  4.9             0.5
                        Equipment
                        Incentive
                        Measure Phase 2.
                                         -------------------------------
E................        Sub-Total......            4.92             0.5
F................        Grand Total for          20.892           0.607
                          CARB (C+D+E).
                                         -------------------------------
                   SJVUAPCD:
                   Submitted Measures:
                       Rule 4311                    0.19            0.03
                        (``Flares'').
                       Rule 4306                    0.19               0
                        (``Boilers,
                        Steam
                        Generators, and
                        Process Heaters--
                        Phase 3'').
                       Rule 4320                       0               0
                        (``Advanced
                        Emission
                        Reduction Option
                        for Boilers,
                        Steam
                        Generators, and
                        Process Heaters
                        greater than 5
                        MMBtu/hr'') \c\.
                       Rule 4352                     0.5            0.04
                        (``Solid Fuel
                        Fired Boilers,
                        Steam
                        Generators, and
                        Process
                        Heaters'').
                       Rule 4354                     0.2            0.04
                        (``Glass Melting
                        Furnaces'').

[[Page 60518]]

 
                       Rule 4702                    0.61               0
                        (``Internal
                        Combustion
                        Engines'').
                       Residential Wood                0            0.33
                        Burning
                        Incentive
                        Measure.
                                         -------------------------------
G................        Sub-Total......            1.69            0.44
                   Measures Not Yet
                    Presented for Board
                    Consideration:
                       Rule 4550                       0            0.32
                        (``Conservation
                        Management
                        Practices'').
                                         -------------------------------
H................        Sub-Total......               0            0.32
                                         -------------------------------
I................        Grand Total for            1.69            0.76
                          SJVUAPCD (G+H).
                                         -------------------------------
J................        Grand Total               22.58            1.37
                          (F+I).
                                         -------------------------------
K................  Assuming maximum SIP             6.01           -0.86
                    credit, total
                    reductions remaining
                    as commitments (B-J).
------------------------------------------------------------------------
Sources: 2021 Progress Report, Table 2 and Table 3.
\a\ As discussed herein, the EPA has taken final action to approve
  CARB's HDVIP and PSIP measure into the California SIP but we are not
  yet proposing SIP credit for these two measures.
\b\ Given the complexities involved in regulating locomotive emissions,
  we have conservatively excluded from our analysis the emission
  reduction estimates in the 2021 Progress Report for CARB's In-Use
  Locomotive Measure.
\c\ The District's draft staff report for Rule 4306 and Rule 4320
  estimate emission reductions of 0.19 tpd NOX and 0.45 tpd NOX,
  respectively, in 2024. However, the District notes that it is not
  proposing the emission reductions from Rule 4320 for SIP credit at
  this time. SJVUAPCD, ``Draft Staff Report, Proposed Amendments to Rule
  4306 (Boilers, Steam Generators, and Process Heaters--Phase 3),
  Proposed Amendments to Rule 4320 (Advanced Emission Reduction Options
  for Boilers, Steam Generators, and Process Heaters Greater Than 5.0
  MMBtu/hr),'' November 25, 2020, 4.

    Assuming the EPA were to agree with the maximum credit for the 
emission reductions estimated by CARB and the District in the 2021 
Progress Report, these additional measures could achieve emission 
reductions of 22.58 tpd NOX and 1.37 tpd direct 
PM2.5. Combined with the reductions from additional measures 
already approved by EPA into the California SIP (5.29 tpd 
NOX and 1.69 tpd direct PM2.5, per Row C of Table 
1 of this proposed rule), the State would achieve emission reductions 
of 27.87 tpd NOX and 3.06 tpd direct PM2.5. 
Compared to the combined aggregate tonnage commitments, the State would 
have remaining aggregate tonnage commitments of 6.01 tpd NOX 
and would have exceeded the aggregate tonnage commitments by 0.86 tpd 
direct PM2.5. More specifically, CARB would have remaining 
commitments of 6.65 tpd NOX and 0.03 tpd direct 
PM2.5, and the District would have exceeded its commitments 
by 0.64 tpd NOX and 0.89 tpd direct PM2.5.
    However, given the remaining NOX commitments for CARB, 
which are approximately 3% of the NOX emission reductions 
modeled to attain the 2012 annual PM2.5 NAAQS in the SJV by 
2025, we have given additional consideration to the evidence of 
emission reductions for two source categories that have large emission 
reduction estimates: Heavy-Duty I/M and the Agricultural Equipment 
Incentive Measures, including the NRCS portion of the Phase 1 measure 
adopted by CARB in 2019 and the Phase 2 measure slated for 2024 
consideration, per the 2021 Progress Report.
    With respect to Heavy-Duty I/M, in the Valley State SIP Strategy, 
CARB originally estimated that it would achieve 6.8 tpd NOX 
and <0.1 tpd direct PM2.5 in 2025 and described the 
regulatory concepts that would reflect the current (as of 2018) 
``advanced engine and exhaust control technologies, including on-board 
diagnostics (OBD).'' \190\ Since that time, as described in the State's 
2021 Progress Report and the EPA's 2021 Proposed Rule, California has 
developed additional provisions related to Heavy-Duty I/M that the 
State estimates would achieve emission reductions of 14.7 tpd 
NOX and 0.03 tpd direct PM2.5 in 2025.\191\
---------------------------------------------------------------------------

    \190\ Valley State SIP Strategy, 19-20 and Table 8.
    \191\ 2021 Progress Report, 19. CARB notes that further detail 
on emission reduction calculations can be found in the CARB staff 
report on Heavy-Duty I/M, released October 15, 2021. See, CARB, 
``Staff Report: Initial Statement of Reasons, Public Hearing to 
Consider the Proposed Heavy-Duty Inspection and Maintenance 
Regulation,'' October 8, 2021, (``Heavy-Duty I/M ISOR'') and App. H 
(``Proposed Heavy-Duty Inspection and Maintenance Regulation, 
Standardized Regulatory Impact Assessment'').
---------------------------------------------------------------------------

    While the EPA would still not propose to approve a specific amount 
of SIP-creditable reductions until after the State submits such measure 
in final form to the EPA as a revision to the SIP, we have re-examined 
the role of the potential additional emission reductions from Heavy-
Duty I/M presented by CARB. As a qualitative matter, we agree that the 
requirements under California Senate Bill 210 (2019) that heavy-duty 
vehicles comply with Heavy-Duty I/M in order to register annually with 
the California Department of Motor Vehicles, as well as the 
implementation of roadside emissions monitoring (i.e., the Portable 
Emissions AcQuisition System, ``PEAQS'') in the SJV to detect high 
emitting vehicles between periodic test cycles, are tangible additions 
that would increase the emission reductions relative to what was 
contemplated at the time of Plan adoption in November 2018 (by the 
District) and January 2019 (by CARB).
    As a quantitative matter, however, the scale of the estimated 14.7 
tpd NOX emission reductions is roughly half the remaining 
aggregate commitment of 28.59 tpd NOX and represents 7.1% of 
the 207.38 tpd NOX modeled for attainment and a substantial 
increase from CARB's original estimate of 6.8 tpd NOX (3.3% 
of the 207.38 tpd NOX). This 14.7 tpd NOX 
represents a substantial quantity that, pursuant to the Ninth Circuit 
Memorandum Opinion, must be supported by evidence to ``ensure that 
California and the District have a plausible strategy for achieving 
this portion of the attainment strategy'' in order to satisfy the 
second factor of the three-factor aggregate commitment test.\192\ While 
CARB documented its extensive regulatory and technical

[[Page 60519]]

analyses in the measure's Initial Statement of Reasons and associated 
appendices,\193\ CARB has not provided the detailed basis of its 
calculations of 14.7 tpd NOX and 0.03 tpd direct 
PM2.5 emission reductions to the EPA. Given that CARB may do 
so in a future control measure SIP submission, and we lack the record 
evidence to do so here, we do not suggest an alternative amount of 
emission reduction from Heavy-Duty I/M in this proposed rule. Rather, 
we note that the more detailed calculations and technical report 
necessary to support such an estimate, specific to the SJV and to 
annual average emission reductions in 2025, are not available, and 
therefore we do not have sufficient support in the record at this time 
to rely on the State's estimated reductions, in line with the Ninth 
Circuit Memorandum Opinion.
---------------------------------------------------------------------------

    \192\ See Medical Advocates for Healthy Air v. EPA, Case No. 20-
72780, Dkt. #58-1, 7 (9th Cir., April 13, 2022).
    \193\ Heavy-Duty I/M ISOR and, for example, Heavy-Duty I/M ISOR, 
App. D (``Emissions Inventory Methods and Results, Proposed Heavy-
Duty Inspection and Maintenance Regulation'') and App. H (``Proposed 
Heavy-Duty Inspection and Maintenance Regulation, Standardized 
Regulatory Impact Assessment'').
---------------------------------------------------------------------------

    With respect to mobile agricultural equipment, the EPA has taken 
final action to approve the Funding Agricultural Replacement Measures 
for Emission Reductions (FARMER) program and the Carl Moyer Memorial 
Air Quality Standards Attainment Program (``Carl Moyer'') portions of 
CARB's first incentive measure on agricultural equipment in the SJV 
(``Agricultural Equipment Incentive Measure-Phase 1'') and proposed in 
our 2021 Proposed Rule to credit emission reductions of 4.46 tpd 
NOX and 0.26 tpd direct PM2.5 towards CARB's 
aggregate tonnage commitments.\194\ CARB has estimated that it will 
achieve 4.9 tpd additional NOX reductions, and 0.5 tpd 
additional direct PM2.5 reductions through a second 
agricultural equipment incentive measure. In light of the Ninth Circuit 
Memorandum Opinion, and its finding that the EPA had not ensured that 
CARB and the District had a ``plausible strategy'' for achieving parts 
of the attainment strategy that relied on incentive-based reductions in 
the face of a budget shortfall for funding these measures, we must 
evaluate whether there is sufficient evidence in the record to 
establish a reasonable basis for concluding that any ``Phase 2'' 
agricultural equipment incentive measure will have sufficient funding 
to achieve the reductions ascribed to it.
---------------------------------------------------------------------------

    \194\ 86 FR 74310, 74332; 86 FR 73106, 73109.
---------------------------------------------------------------------------

    As we noted in the EPA's 2021 Proposed Rule, fewer incentive-based 
emission reductions are needed to demonstrate attainment of the 2012 
annual PM2.5 NAAQS than were required in the portion of the 
SJV PM2.5 Plan addressing the 2006 24-hour PM2.5 
NAAQS that was at issue in the Medical Advocates case.\195\ In the 
Ninth Circuit Memorandum Opinion, the court pointed to a $2.6 billion 
shortfall between what the EPA calculated to be a need for $5 billion 
in funding and the more than $2 billion in funding that the State had 
``identified or anticipated.'' \196\ Notably, funding for the Carl 
Moyer, California Assembly Bill 617, and FARMER programs were included 
in the ``identified or anticipated'' portion of the State's funding 
analysis, and not the ``incentive funding gap'' for which the Court 
found EPA's explanations justifying approval to be overly 
speculative.\197\ Accordingly, we do not consider reliance on 
reductions from a Phase 2 agricultural equipment incentive measure to 
be prohibited by the Ninth Circuit Memorandum Opinion, to the extent 
that a Phase 2 rule would rely on the same, existing programs, and 
provided that evidence of sufficient identified or reasonably 
anticipated funding exists in the record.
---------------------------------------------------------------------------

    \195\ 86 FR 74310, 74330. This is due to greater-than-expected 
reductions from committed to and substitute non-incentive regulatory 
measures, such as the Agricultural Burning Phase-Out Measure.
    \196\ Medical Advocates for Healthy Air v. EPA, Case No. 20-
72780, Dkt. #58-1, 7; 85 FR 44192, 44201.
    \197\ CARB Staff Report, 27 (Table 9).
---------------------------------------------------------------------------

    As described in the EPA's analysis of the cost-effectiveness of the 
Agricultural Equipment Incentive Measure-Phase 1, based on information 
provided by CARB, the total project costs resulting in these emission 
reductions were $155 million for FARMER and $125 million for Carl 
Moyer, or $280 million combined.\198\ As described in the EPA's 2021 
Proposed Rule,\199\ the SJV portion of the FARMER funding has typically 
been 80% of the State-wide allocation and the first three years of 
FARMER funding for the SJV were $108 million (fiscal year 2017-2018), 
$104.3 million (fiscal year 2018-2019), and $43.84 million (fiscal year 
2019-2020).\200\ For the current fiscal year (2021-2022), the District 
accepted $168.43 million in FARMER funds to replace agricultural 
equipment in the SJV.\201\ Similarly, we noted that CARB expects Carl 
Moyer funding to increase in future years, following the enactment of 
California Assembly Bill 1274.\202\
---------------------------------------------------------------------------

    \198\ Memorandum dated June 22, 2020, from Rebecca Newhouse, EPA 
Region IX, to docket number EPA-R09-OAR-2019-0318, Subject: ``Cost-
effectiveness of Emission Reductions from the Valley Incentive 
Measure and Estimated Future Funding Needs for Additional 
Agricultural Equipment Replacements'' (``EPA Cost-Effectiveness 
Memo'').
    \199\ 86 FR 74310, 74337.
    \200\ CARB, ``Funding Agricultural Replacement Measures for 
Emission Reductions (FARMER) Program, San Joaquin Valley APCD,'' as 
reported through September 30, 2020.
    \201\ SJVUAPCD, ``Item Number 9: Accept $168,425,600 in State 
FARMER Program Funds for Use in the District's Agricultural 
Equipment Replacement Project,'' March 17, 2022.
    \202\ 2021 Progress Report, 22.
---------------------------------------------------------------------------

    Thus, while future funding allocations are subject to annual State 
and local funding cycles, given the renewed, large investment in the 
fiscal year 2021-2022 FARMER program, potential for increases in 
funding for the Carl Moyer program, and the success of these programs 
in meeting enforceability criteria for purposes of crediting emission 
reductions, the EPA anticipates that CARB will be able to develop an 
additional agricultural equipment incentive measure (``Agricultural 
Equipment Incentive measure-Phase 2'') that has funding levels 
comparable or larger than those for Phase 1 (i.e., including the $168 
million accepted by the District in March 2022) and that CARB's 
emission reduction estimates of 4.9 tpd NOX and 0.5 tpd 
direct PM2.5 by 2025, per the 2021 Progress Report, are 
reasonable and supported by identified or reasonably anticipated 
funding.
    However, we have not yet taken final action on the NRCS portion of 
the Agricultural Equipment Incentive Measure-Phase 1 and, for this 
proposed rule, do not rely on the estimated emission reductions for 
that portion of the Agricultural Equipment Incentive Measure-Phase 1 
(i.e., 0.64 tpd NOX and 0.04 tpd direct PM2.5). 
Looking forward in time, this suggests some uncertainty regarding 
creditability of emission reductions from any portion of a Phase 2 
agricultural equipment incentive measure that may be implemented 
through the NRCS program.
    Furthermore, for any measure, to the extent that CARB or the 
District assumed a 100% rule effectiveness rate where the EPA is not 
able to confirm and approve such a rate, further discounts to the 
emission reductions estimated may be warranted in certain cases.\203\ 
Accordingly, the overall remaining NOX commitment could be 
larger than 6.01 tpd and the anticipated

[[Page 60520]]

excess emission reductions for direct PM2.5 could be smaller 
than 0.86 tpd.
---------------------------------------------------------------------------

    \203\ For example, the District originally sought SIP credit of 
0.26 tpd direct PM2.5 emission reductions from Rule 4901 
and the EPA is proposing 0.2 tpd direct PM2.5 based on a 
75% rule effectiveness rate. Similarly, CARB and the District sought 
SIP credit of 1.04 tpd NOX and 1.54 tpd direct 
PM2.5 emission reductions from the Agricultural Burning 
Phase-out Measure and the EPA is proposing 0.83 tpd NOX 
and 1.23 tpd direct PM2.5 based on an 80% rule 
effectiveness rate.
---------------------------------------------------------------------------

    Notwithstanding some uncertainty as to the scale of emission 
reductions from the Heavy-Duty I/M and the Agricultural Equipment 
Incentive Measures (i.e., assuming that the additional measures with 
discrete emission reduction estimates in the 2021 Progress Report 
achieve their respective emission reductions), there remains at least 
6.65 tpd NOX and 0.03 tpd direct PM2.5 in CARB's 
commitment for which the record does not contain a specific and 
plausible strategy to achieve. In our 2021 Proposed Rule we discussed 
two possible ways that CARB could fill this gap: (1) additional 
reductions from committed or substitute measures named by CARB, and (2) 
a hypothetical inter-pollutant trading of excess direct 
PM2.5 emission reductions by the District for any shortfall 
in NOX emission reductions by CARB. The Ninth Circuit 
Memorandum Opinion has established that these concepts in the absence 
of a specific SIP revision are too speculative and do not constitute a 
``plausible strategy'' for achieving this portion of the commitment.
    With respect to additional reductions from committed measures, in 
the 2021 Proposed Rule, we explored potential reductions from two 
incentive-based measures: Accelerated Turnover of Trucks and Buses 
Incentive Projects, and Accelerated Turnover of Off-road Equipment 
Incentive Projects.\204\ CARB initially estimated that they would 
achieve 8 tpd NOX reductions from Accelerated Turnover of 
Trucks and Buses Incentive Projects, and 1.5 tpd NOX 
reductions from Accelerated Turnover of Off-road Equipment Incentive 
Projects.\205\ However, CARB did not propose a measure to its board for 
either measure by 2021, as it had committed to do, nor to our knowledge 
has CARB started the public process for enforceable measures to be 
submitted to the EPA for inclusion as control measures in the 
California SIP.
---------------------------------------------------------------------------

    \204\ 86 FR 74310, 74335.
    \205\ Valley State SIP Strategy, Table 7.
---------------------------------------------------------------------------

    In the 2021 Progress Report, CARB acknowledged that many of the 
project lives do not span the attainment year \206\ and, thus, while 
these projects accelerate emission reductions and benefit communities 
in the SJV, the projects that qualify for SIP credit may be limited for 
the purposes of the 2012 annual PM2.5 NAAQS Serious area 
attainment demonstration. In our 2021 Proposed Rule, we acknowledged 
these weaknesses in these incentive programs, but we nonetheless 
assumed that these measures may ultimately result in SIP-creditable 
emission reductions for a portion of the combined 9.5 tpd 
NOX.\207\ In light of the Ninth Circuit Memorandum Opinion, 
the EPA does not consider it appropriate to rely on reductions that 
have been rendered substantially less likely to occur by the State's 
update indicating that few emissions from these projects may be 
creditable.
---------------------------------------------------------------------------

    \206\ 2021 Progress Report at 24 and 32. Generally, mobile 
source incentive projects implemented under the Carl Moyer program 
are under contract only during the ``project life'' and may not be 
credited with SIP emission reductions after the project life ends. 
EPA Region IX ``Technical Support Document for EPA's Rulemaking for 
the California State Implementation Plan California Air Resources 
Board Resolution 19-26 San Joaquin Valley Agricultural Equipment 
Incentive Measure,'' February 2020, 12-13.
    \207\ 86 FR 74310, 74335.
---------------------------------------------------------------------------

    Furthermore, while the State continues to invest heavily in the 
replacement of older, dirty heavy-duty vehicles and equipment on a 
State-wide basis,\208\ we are not aware of a document that identifies 
specific funding amounts applied to the replacement of such equipment 
in the SJV within the specific timeline of the Plan's demonstration of 
attainment of the 2012 annual PM2.5 NAAQS by December 31, 
2025. In brief, the amount of funding that is specific to the SJV for 
these two measures for purposes of attainment of the 2012 annual 
PM2.5 NAAQS is unclear, and this renders more speculative at 
least a portion of the large scale of NOX emission 
reductions originally anticipated.\209\
---------------------------------------------------------------------------

    \208\ See, e.g., CARB, ``Proposed Fiscal Year 2021-22 Funding 
Plan for Clean Transportation Incentives, Appendix D: Long-Term 
Heavy-Duty Investment Strategy,'' release date October 8, 2021.
    \209\ The EPA also notes that, for regulatory measures that have 
large estimated emission reductions, rather than incentive-based 
measures, CARB estimated that its Low-Emission Diesel Fuel 
Requirement would achieve an additional 1 tpd NOX and 0.1 
tpd direct PM2.5 reductions. However, without near-term 
adoption and submission, its associated emission reductions may not 
be creditable towards the aggregate tonnage commitment for 2025.
---------------------------------------------------------------------------

    With respect to substitute measures under development, CARB points 
to the In-Use Locomotive Rule (and estimates emission reductions of 
1.14 tpd NOX and 0.03 tpd direct PM2.5 by 2025 in 
the SJV), which is slated for 2022 Board consideration.\210\ However, 
as noted in our 2021 Proposed Rule,\211\ given the complexities 
involved in regulating locomotive emissions, we have conservatively 
excluded from our analysis the emission reduction estimates in the 2021 
Progress Report for CARB's In-Use Locomotive Measure.
---------------------------------------------------------------------------

    \210\ 2021 Progress Report, 20-21. Additional information on 
CARB's regulatory concepts for the In-Use Locomotive Measure are 
available at: https://ww2.arb.ca.gov/our-work/programs/reducing-rail-emissions-california/locomotives-and-railyards-meetings-workshops.
    \211\ 86 FR 74310, 74334, fn. 228.
---------------------------------------------------------------------------

    In addition, CARB has identified further measures that were not 
included in the original control measure commitments that may provide 
emission reductions toward CARB's aggregate tonnage commitments.\212\ 
These measures include Cargo Handling Equipment Registration, 
Construction and Mining Equipment Measure, and Co-Benefits from the 
Climate Program. However, we do not have information as to what these 
measures might entail, when the State may adopt or implement them, and 
what scale of emission reductions they could potentially achieve.
---------------------------------------------------------------------------

    \212\ CARB, ``SJV PM2.5 SIP Measure Tracking,'' 
September 2021, 3. Available at: https://ww2.arb.ca.gov/resources/documents/2018-san-joaquin-valley-pm25-plan.
---------------------------------------------------------------------------

    Based on the lack of information on funding and process for heavy-
duty and off-road equipment incentive-based measures and the lack of 
information on other potential substitute measures, such as a 
Construction and Mining Equipment Measure, and in light of the Ninth 
Circuit Memorandum Opinion, we have reconsidered our evaluation of this 
prospect and now propose that there is not sufficient evidence to show 
that the Valley State SIP Strategy contains a ``plausible strategy'' to 
achieve the remaining NOX and direct PM2.5 
emission reductions needed for attainment.
    The other approach that the 2021 Proposed Rule discusses for 
filling the gap in CARB's strategy for achieving its commitment is 
based on a hypothetical future SIP revision. In the 2021 Progress 
Report, CARB and the District provided additional emissions analysis to 
assess how excess direct PM2.5 emission reductions could be 
converted to equivalent NOX emission reductions using an 
inter-pollutant trading ratio rooted in the sensitivity analyses of the 
2018 PM2.5 Plan.\213\ CARB and the District have not 
formally submitted this analysis as a SIP revision to the EPA or 
requested that the EPA apply such inter-pollutant trading for purposes 
of fulfilling the aggregate tonnage commitments through an equivalent 
amount of emission reductions.
---------------------------------------------------------------------------

    \213\ 2021 Progress Report, Table 4 and 33-37.
---------------------------------------------------------------------------

    Consistent with past EPA action on PM2.5 planning SIP 
submissions for the SJV,\214\ where the State submits a SIP

[[Page 60521]]

revision that would substitute reductions in one pollutant to achieve a 
tonnage commitment concerning a different pollutant (e.g., substituting 
excess direct PM2.5 reductions to satisfy a NOX 
reduction commitment), it must include an appropriate inter-pollutant 
trading (IPT) ratio and the technical basis for such ratio in the plan 
submission itself, along with the requisite public process. The EPA 
will review any such IPT ratio and its bases before approving or 
disapproving any such SIP revision. The possibility of a future SIP 
submission discussing IPT does not constitute a ``plausible strategy'' 
for achieving reductions that are modeled to result in attainment. 
Thus, at this time, we are not proposing to approve any particular 
inter-pollutant trading approach for purposes of meeting the aggregate 
tonnage commitments, nor applying any excess reductions of one 
pollutant towards fulfilling a portion of committed reductions of the 
other pollutant.
---------------------------------------------------------------------------

    \214\ For example, the EPA has approved an inter-pollutant 
trading mechanism for use in transportation conformity analyses for 
the 2006 24-hour PM2.5 NAAQS. 85 FR 44192, 44204. In that 
same final rule, the EPA approved the State's demonstration that it 
had fulfilled prior aggregate tonnage commitments, in part, by using 
an inter-pollutant trading approach that the EPA found adequate. 85 
FR 44192, 44205; see also proposed rule at 85 FR 17382, 17406-17407 
and associated EPA's General Evaluation TSD, Table III-C and section 
IV.
---------------------------------------------------------------------------

    The additional evaluation we have discussed herein as part of our 
reconsideration of the State's enforceable commitments requires us to 
re-evaluate the EPA's three-factor test for enforceable commitments. 
Based on our reconsideration, and consistent with the Ninth Circuit 
Memorandum Opinion, we retain our proposed findings that the State's 
commitments meet the first factor (the commitment represents a limited 
portion of the required reductions, i.e., 13.8% of the NOX 
and 8.0% of the direct PM2.5 emission reductions necessary 
to attain) and the third factor (the commitment is for a reasonable and 
appropriate timeframe) of the three-factor test. However, we now 
propose that the State's commitments do not meet the second factor 
(regarding the State's capability to fulfill its commitments). Our 
analysis and findings for the first and third factors are presented in 
section IV.F.3.e of the 2021 Proposed Rule. We provide our reconsidered 
evaluation of the second factor as follows in this proposed rule.
    As the EPA noted in our 2021 Proposed Rule, CARB and the District 
have been capable of developing and adopting many of the regulatory 
measures listed in their respective control measure commitments. 
However, the question before us more precisely is whether such 
substantial progress, coupled with the strategy submitted by the State 
for achieving the remaining reductions which the State has modeled as 
leading to attainment, is sufficient to show that the State is capable 
of fulfilling its entire aggregate tonnage commitments by 2025. Several 
components of our reconsideration suggest that the State may not be 
capable of fulfilling the entire aggregate tonnage commitment, 
particularly with respect to NOX emission reductions from 
additional CARB measures.
    First, in terms of additional measures for which CARB and the 
District provided updated emission reduction estimates, we have given 
additional consideration to the evidence of emission reductions for two 
source categories that have large emission reduction estimates: Heavy-
Duty I/M and the Agricultural Equipment Incentive Measures. For Heavy-
Duty I/M, CARB has not provided to the EPA a sufficient basis for its 
increase in estimated emission reductions from 6.8 tpd NOX 
to 14.7 tpd NOX, where the 14.7 tpd reduction amounts to 
7.1% of the total emission reductions modeled for attainment of the 
2012 annual PM2.5 NAAQS. Although the EPA is confident, 
based on its review, that emission reductions are available in this 
category, and that the State is capable of achieving some amount of 
reductions, the State has not sufficiently supported its assertion that 
it is capable of achieving 14.7 tpd of NOX and 0.03 tpd of 
direct PM2.5. As discussed above, due to uncertainty 
surrounding the NRCS portion of the Agricultural Equipment Incentive 
Measure-Phase 1, we are not relying on reductions from that portion of 
the rule, and the creditability of any NRCS portion of a potential 
future Phase 2 has not been established.
    Furthermore, for any measure, to the extent that CARB or the 
District assumed a 100% rule effectiveness rate where the EPA is not 
able to confirm and approve such a rate, further discounts to the 
emission reduction estimates may be warranted in certain cases.
    Accordingly, the overall remaining NOX commitment could 
be larger than 6.01 tpd and the anticipated excess emission reductions 
for direct PM2.5 could be smaller than 0.86 tpd.
    Second, even if the EPA were to assume maximum credit for the 
additional measures for which CARB and the District provided updated 
emission reduction estimates, CARB, in combination with the District, 
would still need emission reductions of at least 6 tpd NOX 
to fulfill its commitments.\215\ Moreover, the reductions from CARB's 
remaining incentive measures for Heavy-Duty vehicles and off-road 
equipment appear to be limited relative to the combined emission 
reduction estimate of 9.5 tpd NOX in the Plan. Without 
documentation supporting the funding amounts to be applied in the SJV 
within the timeline of the 2012 annual PM2.5 NAAQS portion 
of the SJV PM2.5 Plan, it is not clear that the full amount 
of these estimated reductions is supported by a ``plausible strategy'' 
to achieve them, as required in the Ninth Circuit Memorandum Opinion. 
In addition, the identified substitute measures lack sufficient detail 
to provide support for making up for NOX emission reduction 
shortfalls from CARB's control measure commitments.
---------------------------------------------------------------------------

    \215\ As noted in this proposed rule, if the EPA were to assume 
credit for emission reductions from the additional District 
measures, the District would have exceeded its aggregate tonnage 
commitments by 0.64 tpd NOX and 0.89 tpd direct 
PM2.5.
---------------------------------------------------------------------------

    Given the gap between the reductions needed and the reductions for 
which CARB and the District have presented a non-speculative plan for 
achieving, we now propose that the State has not demonstrated that it 
is capable of fulfilling the remaining aggregate tonnage commitments 
necessary to attain the 2012 annual PM2.5 NAAQS in the SJV 
by December 31, 2025, and therefore find that the SJV PM2.5 
Plan does not meet the second factor of our three-factor test for 
enforceable commitments.
b. Attainment Demonstration
    Based on our reconsideration of the Plan's enforceable commitments 
described in section II.C.3.a of this proposed rule, and our 
reconsideration of the Plan's BACM demonstration for described in 
section II.B, we now propose to disapprove the SJV PM2.5 
Plan's modeled attainment demonstration for the 2012 annual 
PM2.5 NAAQS in the SJV by December 31, 2025. We discuss the 
interrelationship of these nonattainment plan elements as follows.
    Regarding enforceable commitments, CAA section 110(a)(2)(A) 
provides that each SIP ``shall include enforceable emission limitations 
and other control measures, means or techniques . . . as well as 
schedules and timetables for compliance, as may be necessary or 
appropriate to meet the applicable requirements of [the Act].'' Section 
172(c)(6) of the Act, which applies to nonattainment SIPs, is virtually 
identical to section 110(a)(2)(A). The EPA interprets the CAA to allow 
for approval of enforceable commitments that are limited in scope, 
where circumstances exist that warrant the use of such commitments in 
place of

[[Page 60522]]

adopted and submitted measures, and considers three factors in 
determining whether to approve the enforceable commitment.
    Given our proposed finding above that the State has not met the 
second factor of the EPA's three-factor test (i.e., whether the State 
is capable of fulfilling its commitment), the State is left with a gap 
between the reductions that it has modeled as necessary for attainment, 
and the reductions that the EPA may count as constituting the State's 
control plan. Therefore, the EPA proposes that the State's control 
strategy does not include sufficient enforceable measures, pursuant to 
CAA sections 110(a)(2)(A) and 172(c)(6), to achieve the necessary 
emission reductions to attain the 2012 annual PM2.5 NAAQS in 
the SJV by December 31, 2025.
    The lack of an approved control plan to achieve the reductions 
necessary to attain by 2025 is sufficient on its own to compel 
disapproval of the attainment demonstration. However, even if the 
State's control plan was sufficient to lead to attainment in 2025, the 
Public Justice Comment Letter and our reconsidered BACM analysis in 
section II.B of this notice raise additional issues regarding the 
sufficiency of the modeled attainment demonstration.
    The State's attainment demonstration identifies the Bakersfield-
Planz monitor as the design value monitor, and models this monitor as 
achieving the 12.0 [micro]g/m\3\ concentration necessary for attainment 
in 2025.\216\ The State's submission also indicates that the 
Bakersfield-Planz monitor is modeled to read 12.1 [micro]g/m\3\ in 
2024.\217\ This represents a very narrow margin between modeled 
attainment in 2024 and 2025. In light of the Act's requirement to 
demonstrate attainment by the most expeditious date practicable, in 
order for the EPA to approve the Plan's demonstration that the area 
will attain by 2025, the State must also demonstrate that attainment by 
an earlier date is not practicable.
---------------------------------------------------------------------------

    \216\ 2018 PM2.5 Plan, App. K, Table 39.
    \217\ Id. at Table 33.
---------------------------------------------------------------------------

    As explained in section II.B of this notice, the EPA now proposes 
to find that the State has not sufficiently demonstrated that it has 
implemented BACM for all necessary categories of sources. Most notably, 
the State has not sufficiently evaluated the amount of ammonia 
reductions that may be available. In light of the very small (0.1 
[micro]g/m\3\) gap between attaining in 2024 and 2025, and the State's 
sensitivity modeling in its precursor demonstration indicating that a 
30% reduction in ammonia would reduce annual PM2.5 
concentrations at the Bakersfield-Planz monitor by 0.12 [micro]g/m\3\ 
and a 70% reduction would reduce annual PM2.5 concentrations 
at the Bakersfield-Planz monitor by 0.36 [micro]g/m\3\, the State has 
not demonstrated that reductions from sources identified in section 
II.B could not expedite attainment.\218\ As a result, even if the 
State's control plan was sufficiently concrete that the EPA could 
credit all reductions of NOX and direct PM2.5 
that the State indicated that it intended to use to fulfill its 
aggregate commitments, the State is still required to demonstrate that 
the selected attainment year (e.g., 2025) is as expeditious as 
practicable considering potential emission reductions from all plan 
precursors, including ammonia.
---------------------------------------------------------------------------

    \218\ See 2018 PM2.5 Plan, App. G, tables 4 through 
7.
---------------------------------------------------------------------------

    The EPA emphasizes that it is stating both that the Plan does not 
demonstrate that the SJV will attain by 2025 and that the State has not 
demonstrated that it could not attain sooner than 2025. These findings 
are not in tension with one another. Under the Act, the State must 
demonstrate that its control plan will be sufficient to attain the 
NAAQS, and to attain the NAAQS by the most expeditious date 
practicable. The State's failure to demonstrate that it could not 
attain sooner than 2025 is not inconsistent with the State also having 
other analytical or substantive flaws in its control plan to attain by 
2025. The EPA is not proposing to find that the SJV can practicably 
attain by 2024, nor is the EPA proposing to find that the SJV could not 
possibly attain by 2025. Instead, the EPA is proposing, in light of the 
uncertainty regarding ammonia controls, to find that the State has 
failed to demonstrate that it could not practicably attain before 2025, 
and in light of identified deficiencies in the control plan, that the 
State's control strategy for attaining by 2025 is flawed.
    Furthermore, for the 1997 annual PM2.5 NAAQS, on 
November 8, 2021, the State submitted the ``Attainment Plan Revision 
for the 1997 Annual PM2.5 Standard,'' which was adopted by 
the District on August 19, 2021, and by CARB on September 23, 2021 
(``15 [micro]g/m\3\ SIP Revision''). In that submission, the State 
updated its prior air quality modeling to account for more recent 
monitored air quality data. Specifically, the State estimated 2023 
annual average concentrations starting from a 2018 monitored base year 
(i.e., rather than a 2013 base year, in order to reflect updated 
monitored air quality data), and applied updated, scaled relative 
response factors (RRFs) to reflect emissions changes between 2018 and 
2023.\219\ Because this scaling indicated a significant change in the 
modeling results for the 1997 annual PM2.5 NAAQS, and the 
modeling for the 2012 annual PM2.5 NAAQS relies on many of 
the same models and assumptions, the result of the scaling analysis 
introduces additional uncertainty to the modeled attainment 
demonstration for the 2012 PM2.5 NAAQS. Accordingly, we 
recommend updated modeling analysis for the 2012 annual 
PM2.5 NAAQS.
---------------------------------------------------------------------------

    \219\ 15 [micro]g/m\3\ SIP Revision, Ch. 5, 5-9 to 5-12. See 
also 15 [micro]g/m\3\ SIP Revision, App. K, 64-65. In the 15 
[micro]g/m\3\ SIP Revision, the State used existing modeling runs 
for 2020 and 2024 to compute RRFs for each PM2.5 
component using the standard approach recommended in the EPA's 
Modeling Guidance. Those RRFs were then scaled to reflect emissions 
changes between 2018 and 2023 to arrive at updated RRFs.
---------------------------------------------------------------------------

    As a result of our proposed disapproval of the control plan and the 
uncertainty regarding additional reductions that could be achieved by 
further BACM/BACT level controls for all appropriate plan precursors 
(particularly for ammonia), we now propose to disapprove the attainment 
demonstration for the 2012 annual PM2.5 NAAQS.

D. Reasonable Further Progress Demonstration and Quantitative 
Milestones

1. Summary of 2021 Proposed Rule
    In section IV.G of our 2021 Proposed Rule, the EPA described the 
requirements for RFP and quantitative milestones for a Serious 
PM2.5 nonattainment area, summarized the State's submission 
in the 2018 PM2.5 Plan for the SJV, and presented our 
evaluation thereof.\220\ We briefly summarize those components here and 
rely on the more complete exposition in that proposed rule, except as 
described in section II.D.2 of this proposed rule (i.e., the EPA's 
reconsidered proposal for RFP and quantitative milestones).
---------------------------------------------------------------------------

    \220\ 86 FR 74310, 74338-74345.
---------------------------------------------------------------------------

    Regarding requirements, CAA section 172(c)(2) provides that all 
nonattainment area plans shall require RFP toward attainment. In 
addition, CAA section 189(c) requires that all PM2.5 
nonattainment area plans contain quantitative milestones for purposes 
of measuring RFP, as defined in CAA section 171(1), every three years 
until the EPA redesignates the area to attainment. Section 171(1) of 
the Act defines RFP as the annual incremental reductions in emissions 
of the relevant air pollutant as are required by part D, title I of the 
Act, or as may reasonably be required by the Administrator for the 
purpose of ensuring attainment of the

[[Page 60523]]

NAAQS by the applicable attainment date.
    In addition to the EPA's longstanding guidance on the RFP 
requirements for PM, the Agency has established specific regulatory 
requirements for the PM2.5 NAAQS in the PM2.5 SIP 
Requirements Rule for purposes of satisfying the Act's RFP requirements 
and provided related guidance in the preamble to the rule. 
Specifically, under the PM2.5 SIP Requirements Rule, for a 
PM2.5 attainment plan a State must include an RFP analysis 
that includes, at minimum, the following four components: (1) an 
implementation schedule for control measures; (2) RFP projected 
emissions for direct PM2.5 and all PM2.5 plan 
precursors for each applicable milestone year, based on the anticipated 
control measure implementation schedule; (3) a demonstration that the 
control strategy and implementation schedule will achieve reasonable 
progress toward attainment between the base year and the attainment 
year; and (4) a demonstration that by the end of the calendar year for 
each triennial milestone date for the area, pollutant emissions will be 
at levels that reflect either generally linear progress or stepwise 
progress in reducing emissions on an annual basis between the base year 
and the attainment year.\221\ Additionally, states should estimate the 
RFP projected emissions for each quantitative milestone year by sector 
on a pollutant-by-pollutant basis.\222\
---------------------------------------------------------------------------

    \221\ 40 CFR 51.1012(a).
    \222\ 81 FR 58010, 58056.
---------------------------------------------------------------------------

    Section 189(c) of the Act requires that PM2.5 attainment 
plans include quantitative milestones that demonstrate RFP. The purpose 
of the quantitative milestones is to allow periodic evaluation of the 
State's progress towards attainment of the PM2.5 NAAQS in 
the area consistent with RFP requirements. Because RFP is an annual 
emission reduction requirement and the quantitative milestones are to 
be achieved every three years, when a State demonstrates compliance 
with the quantitative milestone requirement, it should also demonstrate 
that RFP has been achieved during each of the relevant three years. 
Quantitative milestones should provide an objective means to evaluate 
progress toward attainment meaningfully, e.g., through imposition of 
emissions controls in the attainment plan and the requirement to 
quantify those required emissions reductions on the schedule approved 
by the EPA and thus required to meet RFP.
    As we noted in the 2021 Proposed Rule, the CAA does not specify the 
starting point for counting the three-year periods for quantitative 
milestones under CAA section 189(c). In the General Preamble and 
General Preamble Addendum, the EPA interpreted the CAA to require that 
the starting point for the first three-year period be the due date for 
the Moderate area plan submission.\223\ Consistent with this 
longstanding interpretation of the Act, the PM2.5 SIP 
Requirements Rule requires that each plan for a Serious 
PM2.5 nonattainment area that demonstrates attainment by the 
end of the 10th calendar year following the date of designation contain 
quantitative milestones to be achieved no later than milestone dates 
7.5 years and 10.5 years from the date of designation of the area.\224\ 
The 2018 PM2.5 Plan includes a demonstration designed to 
show attainment by the end of the 10th calendar year following 
designations (i.e., December 31, 2025). Because the EPA designated the 
SJV nonattainment for the 2012 annual PM2.5 NAAQS effective 
April 15, 2015,\225\ the applicable quantitative milestone dates for 
purposes of the submitted Serious area plan for this NAAQS in the SJV 
are October 15, 2022, and October 15, 2025.
---------------------------------------------------------------------------

    \223\ General Preamble, 13539 and General Preamble Addendum, 
42016.
    \224\ 40 CFR 51.1013(a)(2)(i).
    \225\ 80 FR 2206.
---------------------------------------------------------------------------

    Quantitative milestones must provide for objective evaluation of 
reasonable further progress toward timely attainment of the 
PM2.5 NAAQS in the area and include, at minimum, a metric 
for tracking progress achieved in implementing SIP control measures, 
including BACM and BACT, by each milestone date.\226\
---------------------------------------------------------------------------

    \226\ 81 FR 58010, 58064 and 58092.
---------------------------------------------------------------------------

    The State presents its RFP demonstration and quantitative 
milestones for the 2012 annual PM2.5 NAAQS in Appendix H of 
the 2018 PM2.5 Plan. Following the identification of a 
transcription error in the RFP tables of Appendix H, the State 
submitted a revised version of Appendix H that corrects the 
transcription error and provides additional information on the RFP 
demonstration.\227\ Given the State's conclusions that ammonia, 
SOX, and VOC emissions do not contribute significantly to 
PM2.5 levels that exceed the 2012 annual PM2.5 
NAAQS in the SJV, the RFP demonstration provided by the State only 
addresses emissions of direct PM2.5 and NOX.\228\ 
Similarly, the State developed quantitative milestones based upon the 
Plan's control measure strategy to achieve emission reductions of 
direct PM2.5 and NOX.\229\
---------------------------------------------------------------------------

    \227\ Appendix H to 2018 PM2.5 Plan, submitted 
February 11, 2020, via the EPA State Planning Electronic 
Collaboration System. This revised version of Appendix H replaces 
the version submitted with the 2018 PM2.5 Plan on May 10, 
2019. All references to Appendix H in this proposed rule are to the 
revised version of Appendix H submitted February 11, 2020.
    \228\ 2018 PM2.5 Plan, App. H, H-1.
    \229\ Id. at App. H, H-23 to H-24 (for CARB milestones) and H-20 
to H-22 (for District milestones).
---------------------------------------------------------------------------

    For the 2012 annual PM2.5 NAAQS, the RFP demonstration 
in the Plan follows a stepwise approach due to the time required for 
CARB and the District ``to amend rules, develop programs, and implement 
the emission reduction measures.'' \230\ The revised Appendix H 
provides clarifying information on the RFP demonstration, including 
additional information to justify the Plan's stepwise approach to 
demonstrating RFP. This clarifying information did not affect the 
Plan's quantitative milestones. It is important to note that the State 
evaluated what would be necessary for purposes of meeting RFP premised 
upon its approach to regulating only direct PM2.5 and 
NOX emissions, and upon a December 31, 2025 
attainment date that itself depended upon the State achieving certain 
additional emission reductions though the enforceable commitments.
---------------------------------------------------------------------------

    \230\ Id. at App. H, H-4.
---------------------------------------------------------------------------

    In our 2021 Proposed Rule we further described the State's RFP 
demonstration and quantitative milestones in the SJV PM2.5 
Plan, including, for example, the anticipated implementation schedule 
for CARB and District control measures, projected emissions for each 
RFP year and attainment year, and percent reductions to be achieved in 
each milestone year, which would be consistent with a stepwise 
approach. We noted that the reductions between the 2013 base year and 
2019 milestone year are consistent with generally linear progress 
toward the targeted attainment date, while the reductions by the 2022 
milestone year would fall short of the rate of reductions to show 
generally linear RFP. We also noted that the State relies on more 
substantial direct PM2.5 and NOX emission 
reductions by January 1, 2025, due in large part to CARB and the 
District's reliance on enforceable commitments to achieve additional 
PM2.5 and NOX emission reductions from new 
measures implemented by 2024. Lastly, we noted the State's overall 
conclusion that the adopted control strategy and additional commitments 
for reductions from new control programs by this time are adequate to 
meet the RFP requirement for the 2012 annual PM2.5 NAAQS 
with

[[Page 60524]]

the projected attainment date of December 31, 2025.
    Regarding quantitative milestones, Appendix H of the 2018 
PM2.5 Plan identifies October 15 milestone dates for the 
2019 and 2022 RFP milestone years, the 2025 attainment year, and a 
post-attainment milestone year of 2028.\231\ Appendix H also identifies 
target emissions levels to meet the RFP requirement for direct 
PM2.5 and NOX emissions for each of these 
milestone years,\232\ as shown in Table 6 of our 2021 Proposed Rule, 
and control measures that CARB and the District already have in place 
or plan to implement by each of these years, in accordance with the 
control strategy in the Plan.\233\
---------------------------------------------------------------------------

    \231\ 2018 PM2.5 Plan, App. H, Table H-12.
    \232\ Id. at Table H-5.
    \233\ Id. at H-23 to H-24 (for CARB milestones) and H-20 to H-22 
(for District milestones).
---------------------------------------------------------------------------

    We noted, however, that while quantitative milestones are required 
for 2019 in the context of the Moderate area plan for the 2012 annual 
PM2.5 NAAQS in the SJV (corresponding to the 4.5 years after 
the date of designation), we have already evaluated and approved the 
State's quantitative milestones for 2019, as supplemented by the 2018 
PM2.5 Plan.\234\ Therefore, the EPA is not evaluating the 
2019 milestones for purposes of the State's Serious area plan for the 
2012 annual PM2.5 NAAQS in the SJV.
---------------------------------------------------------------------------

    \234\ 86 FR 67343, 67346.
---------------------------------------------------------------------------

    Although the State's attainment demonstration for the 2012 annual 
PM2.5 NAAQS does not rely on CARB's and the District's 
control measure commitments for emission reductions until 2024,\235\ 
the RFP and quantitative milestone elements of the 2018 
PM2.5 Plan rely on these control measure commitments to 
demonstrate that the plan requires RFP toward attainment.\236\ In our 
2021 Proposed Rule we summarized the specific milestones identified by 
the State for each milestone year and with respect to the control 
measure commitments in each three-year period.
---------------------------------------------------------------------------

    \235\ 2018 PM2.5 Plan, Ch. 4, Table 4-3 (``Emission 
Reductions from District Measures'') and Table 4-9 (``San Joaquin 
Valley Expected Emission Reductions from State Measures'').
    \236\ 2018 PM2.5 Plan, App. H, H-4 to H-10 
(describing commitments by CARB and SJVUAPCD to adopt additional 
measures to fulfill tonnage commitments for 2024 and 2025, including 
``action'' and ``implementation'' dates occurring before 2024 to 
ensure expeditious progress toward attainment).
---------------------------------------------------------------------------

    The EPA presented its evaluation of the State's RFP demonstration 
and quantitative milestones in section IV.G.3 of the 2021 Proposed 
Rule, with additional information in section V of the EPA's 2012 Annual 
PM2.5 TSD. We previously proposed to approve the State's RFP 
demonstration and quantitative milestones.
2. The EPA's Reconsidered Proposal
    As discussed in section II.C.3, we are now proposing to disapprove 
the attainment demonstration for the Serious area plan portion of the 
2018 PM2.5 Plan for the 2012 annual PM2.5 NAAQS 
because we are proposing to not approve the State's control plan to 
achieve the reductions modeled for 2025 and the attainment 
demonstration does not demonstrate that the SJV could not practicably 
attain before 2025. The RFP demonstration in the Plan is deficient 
because it sets out a timeline for implementing the deficient control 
plan, which is not sufficient to ``ensure attainment'' under CAA 
section 171(l). The quantitative milestones do not ``demonstrate [RFP] 
toward attainment by the applicable date'' under CAA section 189(c), 
both because the Plan does not sufficiently demonstrate that the 
control plan will result in attainment, and because the plan does not 
sufficiently establish what the applicable date should be.\237\ As a 
result, the EPA proposes to disapprove the Plan's Serious area RFP 
demonstration and quantitative milestones for the 2012 annual 
PM2.5 NAAQS.
---------------------------------------------------------------------------

    \237\ In addition, as discussed in section II.C.3.a of this 
proposed rule, the EPA notes that of the State's 27 control measure 
commitments, four regulatory measures and four incentive-based 
measures are overdue (i.e., were due for board consideration in 2020 
or 2021). It is not clear, based on the evidence before the EPA, 
that such measures will be presented to the CARB and District boards 
in the 2022 calendar year. Furthermore, to the extent the State 
relies on substitute measures to ultimately fulfill its aggregate 
tonnage commitments in 2025 (e.g., the Agricultural Burning Phase-
out Measure), the State has not provided quantitative milestones as 
part of a SIP revision that would provide for periodic evaluation of 
the State's progress in implementing such substitute measures. In 
addition, the State has not provided quantitative milestones for 
ammonia.
---------------------------------------------------------------------------

E. Motor Vehicle Emission Budgets

1. Summary of 2021 Proposed Rule
    In section IV.I of our 2021 Proposed Rule, the EPA described the 
requirements for motor vehicle emission budgets (``budgets'') for a 
Serious PM2.5 nonattainment area, summarized the State's 
submission in the 2018 PM2.5 Plan for the SJV, and presented 
our evaluation thereof.\238\ We briefly summarize those components here 
and rely on the more complete exposition in that proposed rule, except 
as described in section II.E.2 of this proposed rule (i.e., the EPA's 
reconsidered proposal for budgets).
---------------------------------------------------------------------------

    \238\ 86 FR 74310, 74347-74351.
---------------------------------------------------------------------------

    Section 176(c) of the CAA requires federally funded or approved 
actions in nonattainment and maintenance areas to conform to the SIP's 
goals of eliminating or reducing the severity and number of violations 
of the NAAQS and achieving expeditious attainment of the NAAQS. 
Conformity to the SIP's goals means that such actions will not: (1) 
cause or contribute to new violations of a NAAQS; (2) increase the 
frequency or severity of an existing violation; or (3) delay timely 
attainment of any NAAQS or any interim milestone.
    Actions involving Federal Highway Administration (FHWA) or Federal 
Transit Administration (FTA) funding or approval are subject to the 
EPA's transportation conformity rule, codified at 40 CFR part 93, 
subpart A (``Transportation Conformity Rule''). Under this rule, 
metropolitan planning organizations (MPOs) in nonattainment and 
maintenance areas coordinate with State and local air quality and 
transportation agencies, the EPA, FHWA, and FTA to demonstrate that an 
area's regional transportation plan (RTP) and transportation 
improvement programs (TIP) conform to the applicable SIP. The MPO's 
demonstration is typically done by showing that estimated emissions 
from existing and planned highway and transit systems are less than or 
equal to the applicable budgets contained in adequate or approved 
control strategy implementation plans. An attainment plan for the 
PM2.5 NAAQS should include budgets for the attainment year 
and each required RFP milestone year for direct PM2.5 and 
PM2.5 precursors subject to transportation conformity 
analyses. Budgets are generally established for specific years and 
specific pollutants or precursors and must reflect all of the motor 
vehicle control measures contained in the attainment and RFP 
demonstrations.\239\
---------------------------------------------------------------------------

    \239\ 40 CFR 93.118(e)(4)(v).
---------------------------------------------------------------------------

    In our 2021 Proposed Rule, we described how states should identify 
budgets for direct PM2.5, NOX, and all other 
PM2.5 precursors for which the State and/or the EPA has 
determined that on-road emissions significantly contribute to 
PM2.5 levels in the area for each RFP milestone year and the 
attainment year if the plan demonstrates attainment.\240\ All direct 
PM2.5 SIP budgets should include direct PM2.5 
motor vehicle emissions from tailpipes, brake wear, and tire wear.
---------------------------------------------------------------------------

    \240\ 40 CFR 93.102(b)(2)(iv) and (v).
---------------------------------------------------------------------------

    We described the process by which the State and the EPA should 
determine

[[Page 60525]]

whether other pollutant emissions (i.e., for re-entrained road dust, 
VOC, SO2, and ammonia) contribute significantly to the 
PM2.5 nonattainment problem, either with respect to the 
whole plan or with respect to on-road mobile emissions, and therefore 
be subject to the transportation conformity requirements (i.e., budgets 
for such pollutant(s) must be included in the plan). We further noted 
that transportation conformity trading mechanisms are allowed under 40 
CFR 93.124 where a State establishes appropriate mechanisms for such 
trades and where the basis for the trading mechanism is the SIP 
attainment modeling that establishes the relative contribution of each 
PM2.5 precursor pollutant.
    The EPA's process for determining the adequacy of a budget consists 
of three basic steps: (1) notifying the public of a SIP submittal; (2) 
providing the public the opportunity to comment on the budgets during a 
public comment period; and (3) making a finding of adequacy or 
inadequacy.\241\ The EPA can notify the public by either posting an 
announcement on the EPA's adequacy website notifying the public that 
the EPA has received a SIP submission that will be reviewed to 
determine if the budgets in that submission are adequate for 
transportation conformity purposes (40 CFR 93.118(f)(1)), or through a 
Federal Register notice of proposed rulemaking when the EPA reviews the 
adequacy of submitted motor vehicle emission budgets simultaneously 
with its review and action on the SIP itself (40 CFR 93.118(f)(2)).
---------------------------------------------------------------------------

    \241\ 40 CFR 93.118(f).
---------------------------------------------------------------------------

    The State includes budgets for direct PM2.5 and 
NOX emissions for the 2019 and 2022 RFP milestone years, the 
projected attainment year (2025), and one post-attainment year 
quantitative milestone (2028) in the 2018 PM2.5 Plan.\242\ 
The State establishes separate direct PM2.5 and 
NOX subarea budgets for each county, or partial county (for 
Kern County), in the SJV.\243\ CARB calculated the budgets using 
EMFAC2014,\244\ which was, at the time, CARB's latest version of the 
EMFAC model for estimating emissions from on-road vehicles operating in 
California that had been approved by EPA at the time of Plan 
development, and the latest modeled vehicle miles traveled and speed 
distributions from the SJV MPOs from the Final 2017 Federal 
Transportation Improvement Programs, adopted in September 2016. The 
budgets reflect annual average emissions consistent with the annual 
averaging period of the 2012 annual PM2.5 NAAQS and the 2018 
PM2.5 Plan's RFP demonstration.
---------------------------------------------------------------------------

    \242\ 2018 PM2.5 Plan, App. D, Table 3-3.
    \243\ 40 CFR 93.124(c) and (d).
    \244\ EMFAC is short for EMission FACtor. The EPA announced the 
availability of the EMFAC2014 model for use in State implementation 
plan development and transportation conformity in California on 
December 14, 2015. The EPA's approval of the EMFAC2014 emissions 
model for SIP and conformity purposes was effective on the date of 
publication of the notice in the Federal Register.
---------------------------------------------------------------------------

    In our 2021 Proposed Rule, the EPA noted the following: (1) 2022 
and 2025 are the required budget years applicable to the Serious area 
plan portion of the 2018 PM2.5 Plan for the 2012 annual 
PM2.5 NAAQS in the SJV (and that the attainment year of 2025 
coincided with the latter milestone year based on timing of 
designations); (2) the EPA had approved the budgets for the 2022 RFP 
milestone year in acting on the Moderate area plan and, therefore, will 
not be acting on them again in acting on the Serious area plan; \245\ 
(3) the EPA is not evaluating the 2019 budgets, which would neither be 
used in any future conformity determinations (as the plan contains 
budgets for 2022 and other future years), nor required for the 
submitted Serious area plan; and (4) the EPA would begin the motor 
vehicle emissions budget adequacy and approval review processes for the 
2028 post-attainment milestone year budgets only if the area were to 
fail to attain the standard by December 31, 2025 (the applicable 
Serious area attainment date if the EPA were to finalize approval of 
the 2018 PM2.5 Plan's attainment demonstration).
---------------------------------------------------------------------------

    \245\ 86 FR 67343, 67346.
---------------------------------------------------------------------------

    The Plan's direct PM2.5 budgets include tailpipe, brake 
wear, and tire wear emissions but do not include paved road dust, 
unpaved road dust, and road construction dust emissions.\246\ The State 
did not include budgets for VOC, SO2, or ammonia, consistent 
with its precursor demonstration that control of these precursors would 
not significantly contribute to attainment of the 2012 annual 
PM2.5 NAAQS. The State also included a discussion of the 
significance/insignificance factors for motor vehicle emissions of 
ammonia, SO2, and VOC to support a finding of insignificance 
under the transportation conformity rule.\247\ The State is not 
required to include re-entrained road dust in the PM2.5 
budgets under section 93.103(b)(3) unless the EPA or the State has made 
a finding that these emissions are significant, and neither the State 
nor the EPA has made such a finding. Nevertheless, the Plan includes a 
discussion of the significance/insignificance factors for re-entrained 
road dust and concludes that such emissions are insignificant.\248\ The 
budgets included in the 2018 PM2.5 Plan are shown in Table 3 
of this proposed rule, which is identical to Table 9 of our 2021 
Proposed Rule.
---------------------------------------------------------------------------

    \246\ 2018 PM2.5 Plan, App. D, D-122 to D-123.
    \247\ 40 CFR 93.109(f).
    \248\ 2018 PM2.5 Plan, App. D, D-121.

         Table 3--Motor Vehicle Emission Budgets for the San Joaquin Valley for the 2012 PM2.5 Standard
                                              [Annual average, tpd]
----------------------------------------------------------------------------------------------------------------
                                                                   2022  (RFP year) \a\      2025  (attainment
                                                                 ------------------------          year)
                             County                                                      -----------------------
                                                                     PM2.5        NOX        PM2.5        NOX
----------------------------------------------------------------------------------------------------------------
Fresno..........................................................         0.9        21.2         0.8        14.3
Kern............................................................         0.8        19.4         0.8        12.8
Kings...........................................................         0.2         4.1         0.2         2.7
Madera..........................................................         0.2         3.5         0.2         2.3
Merced..........................................................         0.3         7.6         0.3         5.0
San Joaquin.....................................................         0.6        10.0         0.6         6.9
Stanislaus......................................................         0.4         8.1         0.4         5.6
Tulare..........................................................         0.4         6.9         0.4         4.7
----------------------------------------------------------------------------------------------------------------
Source: 2018 PM2.5 Plan, Appendix D, Table 3-3. Budgets are rounded to the nearest tenth of a ton.

[[Page 60526]]

 
\a\ The EPA has already approved the 2022 RFP budgets in our final rule on the State's Moderate area plan for
  the 2012 annual PM2.5 NAAQS in the SJV.

    In our 2021 Proposed Rule, we also described the State's proposed 
trading mechanism in the 2018 PM2.5 Plan for transportation 
conformity analyses that would allow future decreases in NOX 
emissions from on-road mobile sources to offset any on-road increases 
in direct PM2.5 emissions.
    We presented our evaluation of the State's Serious area budgets for 
the 2012 annual PM2.5 NAAQS in the SJV and proposed to 
approve the 2025 budgets. We noted our preliminary review of the 
budgets submitted for adequacy, which preceded our proposed approval of 
the budgets, consistent with the EPA's general process. Based on 
information in the Plan, we proposed that budgets were not required for 
SO2, VOC, and ammonia.
    Based on our proposed approval of the State's RFP and attainment 
demonstrations, and our review of the budgets in the Plan, we proposed 
that the 2025 budgets for RFP and attainment were consistent with those 
demonstrations, were clearly identified and precisely quantified, and 
met all other applicable statutory and regulatory requirements 
including the adequacy criteria in 40 CFR 93.118(e)(4) and (5). We 
provided a more detailed discussion of the budgets in section VI of the 
EPA's 2012 Annual PM2.5 TSD. We noted that our proposed 
approval of the budgets for the 2012 annual PM2.5 NAAQS did 
not affect the status of the previously approved budgets for the 1997 
PM2.5 NAAQS and related trading mechanism, which remain in 
effect for that PM2.5 NAAQS, nor the 2006 24-hour 
PM2.5 NAAQS and related trading mechanism, which remain in 
effect for that PM2.5 NAAQS.\249\
---------------------------------------------------------------------------

    \249\ 76 FR 69896, 69923-69924 (November 9, 2011) (final rule 
approving direct PM2.5 and NOX budgets for 
2012 and 2014 for the 1997 annual and 24-hour PM2.5 
NAAQS); and 85 FR 44192, 44204 (final rule approving direct 
PM2.5 and NOX budgets for 2020, 2023, and 2024 
for the 2006 24-hour PM2.5 NAAQS); and 86 FR 53150, 
53176-53179 (September 24, 2021) (proposed rule to approve budgets 
from the 2018 PM2.5 Plan for direct PM2.5 and 
NOX for 2017 and 2020 for the 1997 24-hour 
PM2.5 NAAQS). We note that, following our 2021 Proposed 
Rule on the 2012 annual PM2.5 NAAQS portion of the Plan, 
the EPA finalized approval of the 2017 and 2020 budgets for the 1997 
24-hour PM2.5 NAAQS portion of the Plan. 87 FR 4503.
---------------------------------------------------------------------------

    Based on our review of the State's trading mechanism for 
transportation conformity analyses for the 2012 annual PM2.5 
NAAQS, the EPA previously proposed to approve the trading mechanism, 
which would allow future decreases in NOX emissions from on-
road mobile sources to offset any on-road increases in 
PM2.5, using a 6.5:1 NOX:PM2.5 
ratio.\250\ To ensure that the trading mechanism does not affect the 
ability to meet the NOX budget, we noted the following: (1) 
the Plan provides that the NOX emission reductions available 
to supplement the PM2.5 budget would only be those remaining 
after the NOX budget has been met; (2) the SJV MPOs would 
have to document clearly the calculations used in the trading when 
demonstrating conformity, along with any additional reductions of 
NOX and PM2.5 emissions in the conformity 
analysis; and (3) the trading calculations must be performed prior to 
the final rounding to demonstrate conformity with the budgets. We 
summarized the technical bases for our proposed approval of the trading 
mechanism in the 2021 Proposed Rule and in section VI of the EPA's 2012 
Annual PM2.5 TSD.
---------------------------------------------------------------------------

    \250\ For example, a 1 tpd excess of direct PM2.5 
emissions from on-road mobile sources in 2025 could be offset by a 
6.5 tpd reduction in NOX emissions below the 
NOX budget for on-road mobile sources in 2025.
---------------------------------------------------------------------------

    Regarding the duration of budgets for the 2012 annual 
PM2.5 NAAQS, the EPA noted that once budgets are approved, 
they cannot be superseded by revised budgets submitted for the same CAA 
purpose and the same year(s) addressed by the previously approved SIP 
until the EPA approves the revised budgets as a SIP revision. While 
CARB had requested in its letter submitting the 2018 PM2.5 
Plan that the EPA limit the duration of the budgets (i.e., to allow an 
adequacy finding, rather than approval, of future SIP revision of 
budgets to replace the initial budgets),\251\ CARB later clarified that 
since they have submitted EMFAC2021 for EPA review, they no longer 
request that we limit the duration of our approval.\252\
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    \251\ Letter dated May 9, 2019, from Richard W. Corey, Executive 
Officer, CARB, to Mike Stoker, Regional Administrator, EPA Region 
IX, 3.
    \252\ Email dated November 30, 2021, from Nesamani Kalandiyur, 
Manager, Transportation Analysis Section, Sustainable Transportation 
and Communities Division, CARB, to Karina O'Connor, EPA Region IX.
---------------------------------------------------------------------------

    Lastly, in our 2021 Proposed Rule, the EPA proposed to disapprove 
the contingency measure element of the 2018 PM2.5 Plan with 
respect to the Serious area requirements for the 2012 annual 
PM2.5 NAAQS, and we are not modifying our proposed action on 
contingency measures in this proposed rule. Accordingly, we noted that 
if the EPA were to finalize the proposed disapproval of the 2012 annual 
PM2.5 NAAQS Serious area contingency measure element, the 
area would be eligible for a protective finding under the 
transportation conformity rule because the 2018 PM2.5 Plan 
reflects adopted control measures that fully satisfy the emissions 
reductions requirements for the RFP and attainment year of 2025.\253\
---------------------------------------------------------------------------

    \253\ 40 CFR 93.120(a)(3).
---------------------------------------------------------------------------

2. The EPA's Reconsidered Proposal
    Based on the EPA's reconsideration and proposed disapprovals of the 
attainment and RFP demonstrations discussed herein, we have 
reconsidered our proposed approval of the Serious area budgets for the 
2012 annual PM2.5 NAAQS in the SJV. As discussed below, the 
EPA now proposes to disapprove the 2025 RFP and attainment year 
budgets.
    As noted in section I.B of this proposed rule, we are not re-
proposing any action on the Plan's precursor demonstrations for 
SOX and VOC (i.e., we retain our proposed approval that 
SOX and VOC are not plan precursors for the 2012 annual 
PM2.5 NAAQS in the SJV, and therefore SO2 and VOC 
budgets would not be required, consistent with the transportation 
conformity regulation (40 CFR 93.102(b)(2)(v))). However, as discussed 
in section II.A.3 of this proposed rule, the EPA now proposes to 
disapprove the State's precursor demonstration that ammonia does not 
significantly contribute to exceedances of the 2012 annual 
PM2.5 NAAQS in the SJV, and therefore the Plan's precursor 
demonstration would not address the State's obligation to consider 
whether ammonia budgets are necessary in the Serious area plan.
    In the Plan, the State provides a discussion of the significance/
insignificance factors for motor vehicle emissions of ammonia (and 
SO2 and VOC), which would demonstrate a finding of 
insignificance under the transportation conformity rule.\254\ The 
factors typically addressed for significance include an examination of 
the on-road contribution of ammonia to the total emissions, and the 
likelihood of future motor vehicle emission controls. We note that 
annual average ammonia emissions from on-road mobile sources are an 
estimated 3.4 tpd of a total of 324.3 tpd from all sources in 2025, or 
about 1% of the total ammonia emissions.\255\ Based on our

[[Page 60527]]

review, and the small contribution of ammonia emissions from on-road 
mobile sources, the EPA agrees with the State's finding that on-road 
mobile source emissions of ammonia are insignificant and therefore the 
State is not required to include budgets for ammonia in its Serious 
area plan for the 2012 annual PM2.5 NAAQS in the SJV.
---------------------------------------------------------------------------

    \254\ For the criteria and procedures for demonstrating a 
finding of insignificance under the transportation conformity rule, 
see 40 CFR 93.109(f).
    \255\ 2018 PM2.5 Plan, App. B, Table B-5.
---------------------------------------------------------------------------

    With respect to the 2025 RFP and attainment year, the EPA proposes 
to disapprove the direct PM2.5 and NOX budgets 
for 2025, as follows. While the 2025 budgets for RFP and attainment 
were clearly identified and precisely quantified, in this proposed rule 
the EPA proposes to disapprove the State's Serious area RFP and 
attainment demonstrations for the 2012 annual PM2.5 
NAAQS.\256\ The EPA cannot approve budgets where the underlying CAA 
requirements (i.e., RFP and attainment) are disapproved and therefore 
proposes to disapprove the 2025 budgets. The budgets, when considered 
together with all other emission sources, cannot be consistent with the 
applicable requirements for RFP and attainment of the 2012 annual 
PM2.5 NAAQS given the proposed disapprovals of the RFP and 
attainment demonstrations. Therefore, we are proposing to disapprove 
the motor vehicle emissions budgets because they do not meet applicable 
statutory and regulatory requirements, including the adequacy criteria 
specified in the transportation conformity rule.\257\ If the EPA 
finalizes the disapproval, the EPA would concurrently withdraw the 
adequacy finding for the 2025 RFP and attainment year motor vehicle 
emission budgets.\258\
---------------------------------------------------------------------------

    \256\ See 40 CFR 93.118(e)(4)(iii).
    \257\ 40 CFR 93.118(e)(4).
    \258\ The EPA found the 2025 budgets adequate in our 2021 
Proposed Rule. See also, the EPA's 2012 Annual PM2.5 TSD, 
41.
---------------------------------------------------------------------------

    Lastly, given that we now propose to disapprove the Plan's RFP and 
attainment demonstrations for the 2012 annual PM2.5 NAAQS, 
rather than just the Serious area contingency measure element alone (as 
described in our 2021 Proposed Rule), the SJV would not be eligible for 
a protective finding under the transportation conformity rule because 
the 2018 PM2.5 Plan's control measures do not fully satisfy 
the emissions reductions requirements for the RFP and attainment year 
of 2025.\259\
---------------------------------------------------------------------------

    \259\ 40 CFR 93.120(a)(3).
---------------------------------------------------------------------------

    As a result, if the EPA finalizes our proposed disapproval of the 
budgets, upon the effective date of our final rule the area would be 
subject to a conformity freeze under 40 CFR 93.120 of the 
transportation conformity rule. No new transportation plan, TIP, or 
project may be found to conform until the State submits another control 
strategy implementation plan revision fulfilling the same CAA 
requirements, the EPA finds the budgets in the revised plan adequate or 
approves the budgets, the MPO makes a conformity determination for the 
new budgets, and the U.S. Department of Transportation makes a 
conformity determination.\260\ In addition, only transportation 
projects outside of the first four years of the current conforming 
transportation plan and TIP or that meet the requirements of 40 CFR 
93.104(f) during the resulting conformity freeze may be found to 
conform until California submits a new attainment and RFP plan for the 
2012 annual PM2.5 NAAQS and (1) the EPA finds the submitted 
budgets adequate per 40 CFR 93.118 or (2) the EPA approves the new 
attainment plan and conformity to the new plan is determined.\261\ 
Furthermore, if, as a result of our final disapproval action, the EPA 
imposes highway sanctions under section 179(b)(1) of the Act two years 
from the effective date of our final rule, then the conformity status 
of the transportation plan and TIP will lapse on that date and no new 
transportation plan, TIP, or project may be found to conform until 
California submits a new plan for the 2012 annual PM2.5 
NAAQS, and conformity to the plan is determined.\262\
---------------------------------------------------------------------------

    \260\ 40 CFR 93.120(a)(2).
    \261\ Id.
    \262\ 40 CFR 93.120(a)(1).
---------------------------------------------------------------------------

III. Environmental Justice Considerations

    Executive Order 12898 (59 FR 7629, February 16, 1994) requires that 
Federal agencies, to the greatest extent practicable and permitted by 
law, identify and address disproportionately high and adverse human 
health or environmental effects of their actions on minority and low-
income populations. Additionally, Executive Order 13985 (86 FR 7009, 
January 25, 2021) directs Federal Government agencies to assess 
whether, and to what extent, their programs and policies perpetuate 
systemic barriers to opportunities and benefits for people of color and 
other underserved groups, and Executive Order 14008 (86 FR 7619, 
February 1, 2021) directs Federal agencies to develop programs, 
policies, and activities to address the disproportionate health, 
environmental, economic, and climate impacts on disadvantaged 
communities.
    To identify environmental burdens and susceptible populations in 
underserved communities in the SJV nonattainment area and to better 
understand the context of our proposed action on the 2012 annual 
PM2.5 NAAQS portion of the SJV PM2.5 Plan on 
these communities, we conducted a screening-level analysis using the 
EPA's environmental justice (EJ) screening and mapping tool 
(``EJSCREEN'').\263\ Our screening-level analysis indicates that all 
eight counties in the SJV score above the national average for the 
EJSCREEN ``Demographic Index'' (i.e., ranging from 48% in Stanislaus 
County to 61% in Tulare County, compared to 36% nationally).\264\ The 
Demographic Index is the average of an area's percent minority and 
percent low income populations, i.e., the two populations explicitly 
named in Executive Order 12898.\265\ All eight counties also score 
above the national average for demographic indices of ``linguistically 
isolated population'' and ``population with less than high school 
education.''
---------------------------------------------------------------------------

    \263\ EJSCREEN provides a nationally consistent dataset and 
approach for combining environmental and demographic indicators. 
EJSCREEN is available at https://www.epa.gov/ejscreen/what-ejscreen. 
The EPA used EJSCREEN to obtain environmental and demographic 
indicators representing each of the eight counties in the San 
Joaquin Valley. We note that the indicators for Kern County are for 
the entire county. While the indicators might have slightly 
different numbers for the SJV portion of the county, most of the 
county's population is in the SJV portion, and thus the differences 
would be small. These indicators are included in EJSCREEN reports 
that are available in the rulemaking docket for this action.
    \264\ EPA Region IX, ``EJSCREEN Analysis for the Eight Counties 
of the San Joaquin Valley Nonattainment Area,'' August 2022.
    \265\ EJSCREEN reports environmental indicators (e.g., air 
toxics cancer risk, Pb paint exposure, and traffic proximity and 
volume) and demographic indicators (e.g., people of color, low 
income, and linguistically isolated populations). The score for a 
particular indicator measures how the community of interest compares 
with the State, the EPA region, or the national average. For 
example, if a given location is at the 95th percentile nationwide, 
this means that only 5% of the US population has a higher value than 
the average person in the location being analyzed. EJSCREEN also 
reports EJ indexes, which are combinations of a single environmental 
indicator with the EJSCREEN Demographic Index. For additional 
information about environmental and demographic indicators and EJ 
indexes reported by EJSCREEN, see EPA, ``EJSCREEN Environmental 
Justice Mapping and Screening Tool--EJSCREEN Technical 
Documentation,'' section 2 (September 2019).
---------------------------------------------------------------------------

    With respect to pollution, all eight counties score at or above the 
97th percentile nationally for the PM2.5 index and seven of 
the eight counties in the SJV score at or above the 90th percentile 
nationally for the PM2.5 EJ index, which is a combination of 
the Demographic Index and the PM2.5 index. Most counties 
also scored above the 80th percentile for each of 11 additional EJ 
indices included in the EPA's EJSCREEN analysis. In addition, several

[[Page 60528]]

counties scored above the 90th percentile for certain EJ indices, 
including, for example, the Ozone EJ Index (Fresno, Kern, Madera, 
Merced, and Tulare counties), the National Air Toxics Assessment (NATA) 
Respiratory Hazard EJ Index (Madera and Tulare counties), and the 
Wastewater Discharge Indicator EJ Index (Merced, San Joaquin, 
Stanislaus, and Tulare counties).\266\
---------------------------------------------------------------------------

    \266\ Notably, Tulare County scores above the 90th percentile on 
six of the 12 EJ indices in the EPA's EJSCREEN analysis, including 
the PM2.5 EJ Index, which is the highest count among all 
SJV counties.
---------------------------------------------------------------------------

    As discussed in the EPA's EJ technical guidance, people of color 
and low-income populations, such as those in the SJV, often experience 
greater exposure and disease burdens than the general population, which 
can increase their susceptibility to adverse health effects from 
environmental stressors.\267\ Underserved communities may have a 
compromised ability to cope with or recover from such exposures due to 
a range of physical, chemical, biological, social, and cultural 
factors.\268\ The EPA is committed to environmental justice for all 
people, and we acknowledge that the SJV nonattainment area includes 
minority and low income populations that are subject to higher levels 
of PM2.5 and other pollution relative to State and national 
averages, and that such concerns could be affected by this action.
---------------------------------------------------------------------------

    \267\ EPA, ``Technical Guidance for Assessing Environmental 
Justice in Regulatory Analysis,'' section 4 (June 2016).
    \268\ Id. at section 4.1.
---------------------------------------------------------------------------

    If the EPA were to finalize the proposed disapprovals described in 
section II of this proposed rule, California would be required to 
submit a plan revision for the SJV for the 2012 annual PM2.5 
NAAQS to address the identified deficiencies. In addition, as 
summarized in section V of this proposed rule, such final action would 
trigger clocks for the SJV for offset sanctions 18 months after the 
final rule effective date, highway funding sanctions six months after 
the offset sanctions, and the obligation for the EPA to promulgate a 
Federal implementation plan (FIP) within two years of the final rule 
effective date. These obligations ensure that the identified 
deficiencies are resolved in an expeditious manner, consistent with the 
principles of environmental justice.
    We note that, in developing and proposing draft regulations for 
governing board consideration, both CARB and the District consider the 
potential benefits of proposed measures for reducing health hazards to 
disadvantaged communities, such as diesel PM exposure near Heavy-Duty 
truck corridors and indoor smoke exposure from residential wood 
burning. There may be further opportunities to address EJ concerns 
through such control development and implementation.
    More broadly, California law has established additional 
requirements for community-focused action to reduce air pollution in 
the State. For example, in response to California Assembly Bill 617 
(2017), CARB and the District have engaged communities in the SJV, 
performed technical evaluations, and ultimately selected four 
communities (South Central Fresno, Shafter, Stockton, and Arvin/Lamont) 
that are in varying stages of developing and implementing community air 
monitoring programs and community emission reduction programs.\269\ 
Furthermore, grant programs implemented by the local, State, and 
Federal authorities may serve to smooth and accelerate emission 
reductions of PM2.5 and its precursor pollutants in the SJV, 
thereby relieving some of the cumulative burden on disadvantaged 
communities in the SJV nonattainment area.\270\
---------------------------------------------------------------------------

    \269\ For further information, see, e.g., SJVUAPCD, ``Item 
Number 9: Receive Progress Reports on AB617 Community Emission 
Reduction Program Implementation,'' November 18, 2021.
    \270\ For example, through the EPA's Targeted Airshed Grant 
program, the District has competed for, and the EPA has granted 13 
awards to the District from 2015 through 2021, totaling $77.4 
million, to replace older, dirtier woodstoves, agricultural 
equipment, heavy-duty trucks and yard trucks, and agricultural nut 
harvesters with cleaner equipment. A list of the Targeted Airshed 
Grants the EPA awarded in fiscal years 2015-2020 is accessible 
online at https://www.epa.gov/air-quality-implementation-plans/targeted-airshed-grant-recipients. These EPA grants support projects 
to reduce emissions in areas facing the highest levels of ground-
level ozone and PM2.5.
---------------------------------------------------------------------------

IV. Title VI of the Civil Rights Act

    As noted in section I.C of this proposed rule, the EPA received a 
comment letter dated January 28, 2022 (the Public Justice Comment 
Letter), on the 2021 Proposed Rule from a coalition of 13 
organizations.
    The commenters urge the EPA to disapprove the Serious area plan 
``because EPA has failed to require CARB/SJV to provide necessary 
assurances that the State implementation plan complies with Title VI of 
the Civil Rights Act of 1964. The on-going environmental justice and 
air pollution crisis demand EPA reverse course and disapprove the 2012 
plan.'' \271\ To support this argument, the commenters provide 
information regarding the racial demographics of the SJV, the potential 
for disparate impacts from exposure to PM2.5, and specific 
aspects of the SJV PM2.5 Plan that the commenters believe 
result in disparate impacts. The commenters point to past precedent in 
which the EPA has considered compliance with Title VI of the Civil 
Rights Act (Title VI) in the SIP context through CAA section 
110(a)(2)(E). The commenters also note that thus far California has 
provided no ``demonstration'' that the Serious area plan does not cause 
or exacerbate disparate impacts on affected communities in the SJV. 
Thus, the commenters assert that the EPA must disapprove the Serious 
area plan because the State did not provide ``required assurances'' of 
compliance with Title VI.
---------------------------------------------------------------------------

    \271\ Public Justice Comment Letter, 2.
---------------------------------------------------------------------------

    At this time, the EPA has not issued any guidance or regulations 
concerning what might be required for purposes of CAA section 
110(a)(2)(E) as it regards Title VI. The EPA has addressed other 
aspects of section 110(a)(2)(E) in the context of infrastructure SIP 
submissions in its September 2013 ``Guidance on Infrastructure State 
Implementation Plan (SIP) Elements under Clean Air Act Sections 
110(a)(1) and 110(a)(2).'' Similarly, EPA regulations only address 
other aspects of section 110(a)(2)(E) in 40 CFR Sections 51.230-232.

A. Background on CAA Section 110(a)(2)(E)

    For purposes of background, section 110(a)(2)(E) of the CAA, in 
relevant part and with emphasis added, reads as follows:

    (2) Each implementation plan submitted by a State under this 
chapter shall be adopted by the State after reasonable notice and 
public hearing. Each such plan shall--. . .
    (E) provide (i) necessary assurances that the State (or, except 
where the Administrator deems inappropriate, the general purpose 
local government or governments, or a regional agency designated by 
the State or general purpose local governments for such purpose) 
will have adequate personnel, funding, and authority under State 
(and, as appropriate, local) law to carry out such implementation 
plan (and is not prohibited by any provision of Federal or State law 
from carrying out such implementation plan or portion thereof), (ii) 
requirements that the State comply with the requirements respecting 
State boards under section 7428 of this title, and (iii) necessary 
assurances that, where the State has relied on a local or regional 
government, agency, or instrumentality for the implementation of any 
plan provision, the State has responsibility for ensuring adequate 
implementation of such plan provision.\272\
---------------------------------------------------------------------------

    \272\ 42 U.S.C. Section 7410(a)(2)(E) (emphasis added).

[[Page 60529]]

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

    The EPA has previously addressed CAA section 110(a)(2)(E)(i), Title 
VI, and necessary assurances in a 2012 action on a nonattainment plan 
SIP submission from California for purposes of the ozone NAAQS.\273\ 
Comments submitted on the EPA's April 24, 2012 proposed action 
contended that the SIP submission was not in compliance with CAA 
section 110(a)(2)(E) because of alleged violations of Title VI related 
to the regulation of pesticides as precursors to ozone (as volatile 
organic compounds). To evaluate the commenter's concerns, the EPA 
sought additional necessary assurances from the State concerning its 
regulation of pesticides. California submitted additional information 
to the EPA concerning the State's activities that were part of the 
resolution of a Title VI complaint, and additional information 
concerning the State's regulation of pesticides. California submitted 
this information to provide ``necessary assurances'' to the EPA that 
implementation of the requirements of the SIP submission would not 
violate Title VI. The EPA accepted this information as providing 
adequate necessary assurances for purposes of section 110(a)(2)(E) and 
did not require the State to make any substantive changes to support 
approval of the SIP revision.
---------------------------------------------------------------------------

    \273\ 77 FR 65294 (October 26, 2012) (final rule); 77 FR 24441 
(April 24, 2012) (proposed rule).
---------------------------------------------------------------------------

    Commenters in the 2012 action asserted that California had not 
provided sufficient necessary assurances. In the response to comments 
in the 2012 action, the EPA explained that ``Section 110(a)(2)(E), 
however, does not require a State to `demonstrate' it is not prohibited 
by Federal or State law from implementing its proposed SIP revision. 
Rather, this section requires a State to provide `necessary assurances' 
of this.'' \274\ The EPA further explained,
---------------------------------------------------------------------------

    \274\ 77 FR 65294, 65302, column 2.

    Courts have given EPA ample discretion in deciding what 
assurances are ``necessary'' and have held that a general assurance 
or certification is sufficient. (``EPA is entitled to rely on a 
state's certification unless it is clear that the SIP violates state 
law and proof thereof * * * is presented to EPA.'' BCCA Appeal Group 
v. EPA, 355 F.3d 817, 830 fn 11 (5th Cir. 2003)).\275\
---------------------------------------------------------------------------

    \275\ Id.

    The EPA received a petition for review (from groups overlapping 
with the groups that sent the Public Justice Comment Letter) of the 
EPA's October 26, 2012 final action which was reviewed and ultimately 
decided in EPA's favor by the Ninth Circuit Court of Appeals.\276\ The 
Court used an arbitrary and capricious standard of review to evaluate 
the EPA's conclusion that the State had provided adequate ``necessary 
assurances'' that implementation of the SIP is not prohibited by 
Federal law--specifically, Title VI of the Federal Civil Rights Act of 
1964--per the language of section 110(a)(2)(E). The Ninth Circuit found 
that the EPA fulfilled its duty to provide a reasoned judgment because 
its determination was cogently explained and supported by the record. 
In dismissing the petition, the Court explained that ``[t]he EPA has a 
duty to provide a reasoned judgment as to whether the State has 
provided `necessary assurances,' but what assurances are `necessary' is 
left to the EPA's discretion.'' \277\
---------------------------------------------------------------------------

    \276\ El Comit[eacute] Para El Bienstar de Earlimart et al. (El 
Comit[eacute]) v. EPA, 786 F.3d 688 (9th Cir. 2015).
    \277\ 786 F.3d at 700.
---------------------------------------------------------------------------

B. Background on Title VI of the Civil Rights Act of 1964

    For purposes of background context, Title VI prohibits recipients 
of Federal financial assistance from discriminating on the basis of 
race, color, or national origin. Under the EPA's nondiscrimination 
regulations, which implement Title VI and other civil rights laws,\278\ 
recipients of EPA financial assistance are prohibited from taking 
actions in their programs or activities that are intentionally 
discriminatory and/or have an unjustified disparate impact.\279\ This 
includes policies, criteria or methods of administering programs that 
are neutral on their face but have the effect of discriminating.\280\ 
Under the EPA's regulation, recipients of EPA financial assistance are 
also required to have in place certain procedural safeguards, including 
grievance procedures that assure the prompt and fair resolution of 
external discrimination complaints.\281\
---------------------------------------------------------------------------

    \278\ 40 CFR part 7 and part 5.
    \279\ 40 CFR Sections 7.30 and 7.35.
    \280\ 40 CFR Section 7.35(b).
    \281\ 40 CFR Section 7.90.
---------------------------------------------------------------------------

    The EPA carries out its mandate to ensure that recipients of EPA 
financial assistance comply with their nondiscrimination obligations by 
investigating administrative complaints filed with the EPA alleging 
discrimination prohibited by Title VI and the other civil rights laws; 
\282\ initiating affirmative compliance reviews; \283\ and providing 
technical assistance to recipients to assist them in meeting their 
Title VI obligations. In the current matter being addressed in this 
action, no Title VI complaint was filed regarding CARB or the 
District.\284\ Also, the EPA (through the External Civil Rights 
Compliance Office or ECRCO) has not initiated and is not currently 
conducting a compliance review of either CARB or SJVUAPCD.
---------------------------------------------------------------------------

    \282\ 40 CFR Section 7.120.
    \283\ 40 CFR Section 7.115.
    \284\ The EPA's External Civil Rights Compliance Office (ECRCO) 
contacted Mr. Brent Newell, signatory to the Public Justice Comment 
Letter, to see whether the commenters intended to file a Title VI 
administrative complaint with the EPA. In response, the commenters 
stated, ``[t]he comments submitted were neither intended nor styled 
as a Title VI complaint. The comments raise significant issues with 
respect to EPA's proposed approval, including the section 
110(a)(2)(E) issues and EPA's authority and duty to enforce Title 
VI, and we expect EPA to respond to all of the issues in the final 
action/response to comments.'' Email exchange dated February 8, 
2022, between Brent Newell, Public Justice and Lilian Dorka, 
Director, External Civil Rights Compliance Office, EPA Office of 
General Counsel.
---------------------------------------------------------------------------

C. Comments Received on 2021 Proposed Rule

    The commenters raise the issue of compliance with section 
110(a)(2)(E) with respect to Title VI. The commenters contend that the 
SIP submission for the SJV is not in compliance with CAA section 
110(a)(2)(E) because California has not provided necessary assurances 
to ensure that implementation of the SIP is in compliance with Title 
VI. The commenters did not submit these specific comments to CARB or 
the SJVUAPCD during the State's development and adoption process of the 
proposed SIP revisions that are currently at issue. The commenters are 
not required to have done so to raise this issue with the EPA now, but 
as a result, the SIP submission to the EPA does not include any CARB or 
District response concerning this specific issue. In addition, the SIP 
submission does not include specifically identified necessary 
assurances per section 110(a)(2)(E) provided by the State.
    At the outset, the EPA acknowledges the statements in the comment 
letter that the SJV area has historically been designated as 
nonattainment for the PM2.5 NAAQS and that the SJV area 
includes higher representation of persons of color compared to the 
State average. Although in this action the EPA is not proposing to 
disapprove on the basis of CAA section 110(a)(2)(E), if the EPA 
disapproves the Serious area plan as proposed today, California would 
need to submit a revised Serious area plan for the SJV. The EPA expects 
that any such revision would comply with the requirements of section 
110(a)(2)(E) and that CARB and the District will engage with the 
community through notice and comment during the SIP

[[Page 60530]]

development process for its revised Serious area plan prior to 
submitting a revised SIP to the EPA, and specifically with respect to 
necessary assurances relative to Title VI. The new SIP development 
process provides an important opportunity for CARB and the District to 
identify potential adverse disparate impacts on the basis of race, 
color, or national origin from its revised Serious area plan for the 
2012 annual PM2.5 NAAQS and address them as appropriate.
    The EPA acknowledges that it has not issued national guidance or 
regulations concerning implementation of section 110(a)(2)(E) as it 
pertains to consideration of Title VI and disparate impacts on the 
basis of race, color, or national origin in the context of the SIP 
program. Such guidance is forthcoming and will address CAA section 
110(a)(2)(E)'s necessary assurance requirements as they relate to Title 
VI. In the interim, CARB and the District may find existing EPA and DOJ 
Title VI and environmental justice resources useful, even though these 
documents do not relate specifically to CAA section 110(a)(2)(E).\285\ 
Additionally, the EPA's ECRCO is available to provide technical 
assistance regarding Title VI compliance to CARB and/or the District as 
they develop the revised Serious area plan for the 2012 annual 
PM2.5 NAAQS.
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    \285\ See ECRCO's Toolkit Chapter I at: https://www.epa.gov/sites/default/files/2017-01/documents/toolkit-chapter1-transmittal_letter-faqs.pdf, January 18, 2017, and Department of 
Justice ``Title VI Legal Manual (Updated)'' at: https://www.justice.gov/crt/fcs/T6Manual6. See also, e.g., EPA, ``Guidance 
on Considering Environmental Justice During the Development of 
Regulatory Actions,'' (May 2015), and EPA, ``Technical Guidance for 
Assessing Environmental Justice in Regulatory Analysis,'' (June 
2016).
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V. Summary of Proposed Actions and Request for Public Comment

    For the reasons discussed in this proposed rule, under CAA section 
110(k)(3), the EPA proposes to disapprove, as a revision to the 
California SIP, the following portions of the SJV PM2.5 Plan 
for the 2012 annual PM2.5 NAAQS to address the CAA's Serious 
area planning requirements in the SJV nonattainment area:
    (1) the demonstration that BACM, including BACT, for the control of 
ammonia emission sources and for the control of NOX and 
direct PM2.5 building heating emission sources will be 
implemented no later than 4 years after the area was reclassified (CAA 
section 189(b)(1)(B) and 40 CFR 51.1010(a));
    (2) the demonstration that the Plan provides for attainment as 
expeditiously as practicable but no later than December 31, 2025 (CAA 
sections 188(c)(2) and 189(b)(1)(A) and 40 CFR 51.1011(b));
    (3) plan provisions that require RFP toward attainment by the 
applicable date (CAA section 172(c)(2) and 40 CFR 51.1012(a));
    (4) quantitative milestones that are to be achieved every three 
years until the area is redesignated attainment and that demonstrate 
RFP toward attainment by the applicable attainment date (CAA section 
189(c) and 40 CFR 51.1013(a)(2)(i)); and
    (5) motor vehicle emissions budgets for 2025 as shown in Table 3 of 
this proposed rule (CAA section 176(c) and 40 CFR part 93, subpart A).
    We are also proposing to disapprove the State's precursor 
demonstration for ammonia. Our proposed action on the emissions 
inventory and contingency measure elements remains unchanged from our 
2021 Proposed Rule.
    If we finalize the proposed disapprovals for BACM, the attainment 
demonstration, RFP, quantitative milestones, or motor vehicle emission 
budgets, the offset sanction in CAA section 179(b)(2) would apply in 
the SJV 18 months after the effective date of a final disapproval, and 
the highway funding sanctions in CAA section 179(b)(1) would apply in 
the area six months after the offset sanction is imposed.\286\ Neither 
sanction will be imposed under the CAA if the State submits and we 
approve, prior to the implementation of the sanctions, a SIP revision 
that corrects the deficiencies that we identify in our final action. 
The EPA intends to work with CARB and the SJVUAPCD to correct the 
deficiencies in a timely manner.
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    \286\ 40 CFR 52.31.
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    In addition to the sanctions, CAA section 110(c)(1) provides that 
the EPA must promulgate a Federal implementation plan (FIP) addressing 
any disapproved elements of an attainment plan two years after the 
effective date of disapproval unless the State submits, and the EPA 
approves, a SIP submission that cures the disapproved elements.
    Furthermore, if we take final action disapproving the 2012 annual 
PM2.5 NAAQS portion of the SJV PM2.5 Plan, a 
conformity freeze will take effect upon the effective date of any final 
disapproval (usually 30 days after publication of the final action in 
the Federal Register). A conformity freeze means that only projects in 
the first four years of the most recent RTP and TIP can proceed. During 
a freeze, no new RTPs, TIPs, or RTP/TIP amendments can be found to 
conform.\287\
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    \287\ See 40 CFR 93.120(a).
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    We will accept comments from the public on these proposals for the 
next 45 days. The deadline and instructions for submission of comments 
are provided in the DATES and ADDRESSES sections at the beginning of 
this proposed rule.

VI. Statutory and Executive Order Reviews

    Additional information about these statutes and Executive Orders 
can be found at https://www.epa.gov/laws-regulations/laws-and-executive-orders.

A. Executive Order 12866: Regulatory Planning and Review and Executive 
Order 13563: Improving Regulation and Regulatory Review

    This action is not a significant regulatory action and was 
therefore not submitted to the Office of Management and Budget (OMB) 
for review.

B. Paperwork Reduction Act (PRA)

    This action does not impose an information collection burden under 
the PRA, because this proposed SIP disapproval, if finalized, will not 
in-and-of itself create any new information collection burdens, but 
will simply disapprove certain State requirements for inclusion in the 
SIP.

C. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic 
impact on a substantial number of small entities under the RFA. This 
action will not impose any requirements on small entities. This 
proposed SIP partial disapproval, if finalized, will not in-and-of 
itself create any new requirements but will simply disapprove certain 
State requirements for inclusion in the SIP.

D. Unfunded Mandates Reform Act (UMRA)

    This action does not contain any unfunded mandate as described in 
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect 
small governments. This action proposes to disapprove certain pre-
existing requirements under State or local law, and imposes no new 
requirements. Accordingly, no additional costs to State, local, or 
tribal governments, or to the private sector, result from this action.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have 
substantial

[[Page 60531]]

direct effects on the states, on the relationship between the national 
government and the states, or on the distribution of power and 
responsibilities among the various levels of government.

F. Executive Order 13175: Coordination With Indian Tribal Governments

    This action does not have tribal implications, as specified in 
Executive Order 13175, because the SIP revision that the EPA is 
proposing to partially disapprove would not 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, and will not impose 
substantial direct costs on tribal governments or preempt tribal law. 
Thus, Executive Order 13175 does not apply to this action.

G. Executive Order 13045: Protection of Children From Environmental 
Health Risks and Safety Risks

    The EPA interprets Executive Order 13045 as applying only to those 
regulatory actions that concern environmental health or safety risks 
that the EPA has reason to believe may disproportionately affect 
children, per the definition of ``covered regulatory action'' in 
section 2-202 of the Executive Order. This action is not subject to 
Executive Order 13045 because this proposed SIP partial disapproval, if 
finalized, will not in-and-of itself create any new regulations, but 
will simply disapprove certain State requirements for inclusion in the 
SIP.

H. Executive Order 13211: Actions That Significantly Affect Energy 
Supply, Distribution, or Use

    This action is not subject to Executive Order 13211, because it is 
not a significant regulatory action under Executive Order 12866.

I. National Technology Transfer and Advancement Act (NTTAA)

    Section 12(d) of the NTTAA directs the EPA to use voluntary 
consensus standards in its regulatory activities unless to do so would 
be inconsistent with applicable law or otherwise impractical. The EPA 
believes that this action is not subject to the requirements of section 
12(d) of the NTTAA because application of those requirements would be 
inconsistent with the CAA.

J. Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Population

    Executive Order 12898 (59 FR 7629 (February 16, 1994)) establishes 
Federal executive policy on environmental justice. Its main provision 
directs Federal agencies, to the greatest extent practicable and 
permitted by law, to make environmental justice part of their mission 
by identifying and addressing, as appropriate, disproportionately high 
and adverse human health or environmental effects of their programs, 
policies, and activities on minority populations and low-income 
populations in the United States. The EPA's evaluation of this issue is 
contained in the section of the preamble titled ``Environmental Justice 
Considerations.''

List of Subjects 40 CFR Part 52

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

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

    Dated: September 28, 2022.
Martha Guzman Aceves,
Regional Administrator, Region IX.
[FR Doc. 2022-21492 Filed 10-4-22; 8:45 am]
BILLING CODE 6560-50-P