do not always adopt the most efficient practices.'' The commenter
proposes that the precursor analysis should err on maintaining the
presumption that precursors should be regulated and thereby err on the
side of high estimates of potential effectiveness and that because the
State does not do so, its analysis is arbitrary and capricious. The
commenter asserts that the State relies on ``biased assumptions,''
assuming low potential effectiveness from measures not being
implemented, high reductions from Rule 4570, and that making optional
measures mandatory would have no impact. The commenter further contends
that if Rule 4570 is effective, the State should make its most
effective requirements mandatory where feasible and possibly increase
the stringency, and that the EPA should require the State to conduct
further analysis of the rule.
    Response 3.B.4: We disagree with CCEJN's assertions that the State
provides little support for its estimates of ammonia reductions that
have been achieved by existing regulations and that the assumptions it
makes to arrive at those estimates are biased. As discussed in our
proposal, the District discusses in detail in Appendix C of the 2018
PM2.5 Plan how Rule 4570 is structured, the control menu
requirements for each of the CAF operations/sources, and research
papers that support its estimates of ammonia emissions reductions from
the measures.\111\ As the District explains, some of the measures in
Rule 4570 are required to be implemented but the rule also requires
that additional measures be selected from a menu of options. The menu-
based approach was developed to allow facilities flexibility to select
measures that are the most practical and effective for their design and
operation.\112\
---------------------------------------------------------------------------

    \111\ 2018 PM2.5 Plan, Appendix C, pp. C-312 to C-
323.
    \112\ Id.; March 2023 Ammonia Supplement, pp. 25-26.
---------------------------------------------------------------------------

    For those measures that are required to be selected from a menu of
options, the District presents its rationale in Appendix C of the 2018
PM2.5 Plan and Appendix F of the staff report for Rule 4570
for its assumptions about which measure a farmer will select and the
resulting effects on ammonia emissions.\113\ The District references
research studies to support many of its assumptions, and where there is
greater uncertainty about which measures may be selected or the
corresponding ammonia reductions that can be achieved, the District
explains how its assumptions are conservative. CCEJN has not provided
any evidence to refute the District's analysis or conclusions.
Therefore, based on the information presented, the EPA believes that
the District relied on its expertise and the best information available
and applied that information reasonably.
---------------------------------------------------------------------------

    \113\ 2018 PM2.5 Plan, Appendix C, pp. C-311 to C-
323; 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 emissions factors).
---------------------------------------------------------------------------

    Regarding CCEJN's statement that the State should err on the side
of high estimates of potential reductions from additional measures,
given the uncertainties discussed in Responses 3.B.1 and 3.B.2, we find
that the potential emissions reductions achievable in the San Joaquin
Valley from many of the measures are not quantifiable at this time and
that the State drew reasonable conclusions based on the information it
evaluated. While the EPA appreciates that the commenter raises
additional research studies not identified by the State in its
analysis, as discussed in Responses 3.B.1 and 3.B.2, we have reviewed
the studies and find that they do not contradict the State's
conclusions. Thus, we find that the State's analysis of potential
ammonia emissions reductions is neither arbitrary nor capricious.
    We also find that CCEJN's claim that it is well-established that
farmers do not adopt the most efficient practices is not well
supported. To back this claim, the commenter cites two studies
discussing the rates of adoption of precision agriculture
technologies.\114\ However, these studies do not appear to indicate any
reluctance on the part of farmers to adopt the most efficient
practices. As discussed in Response 3.B.2, these papers discuss
widespread adoption of precision agriculture technology while also
acknowledging areas where there are opportunities for increased
adoption, such as for specific crop types or farm sizes and for
specific precision agriculture technologies, such as variable rate
technology.\115\ Where

adoption has been slower, the studies point to feasibility constraints
and the need for more research. For example, Lowenberg-DeBoer and
Erickson (2019) emphasize that precision agriculture has been widely
adopted and that in cases where technologies have been adopted at a
slower pace, the authors attribute it to technological and economic
feasibility challenges.\116\ The study authors also note that the
studies they reviewed hypothesize that more reliable decision rules
that account for the effects of moisture, temperature, soil organic
matter, and other factors on nitrogen response may be needed to
increase variable rate technology adoption.\117\ Whitmore (2019)
similarly notes the complexity and high cost of new equipment as
barriers to wider adoption of precision technology.\118\ CCEJN does not
provide any evidence related to other measures in its letter or other
measures in the State's analysis to support its claim.
---------------------------------------------------------------------------

    \114\ Whitmore (2019) op. cit.; Lowenberg-DeBoer and Erickson
(2019) op. cit.
    \115\ Variable rate technology refers to the use of data and
automation to optimize application of fertilizer, soil amendments,
seed, or plant protection chemicals to optimize crop performance,
save time and money, and reduce environmental impacts.
    \116\ Lowenberg-DeBoer and Erickson (2019) op. cit., p. 1552.
    \117\ Id. at 1564-1565.
    \118\ Whitmore (2019) op. cit.
---------------------------------------------------------------------------

    Finally, we disagree with CCEJN's assertion that if Rule 4570 is
effective, the State must consider making its optional requirements
mandatory. As discussed earlier in this response, if the EPA approves a
state's precursor demonstration showing that a particular
PM2.5 precursor chemical species does not contribute
significantly to PM2.5 levels above the standard in the
area, the state is relieved of the obligation to control emissions of
that precursor from existing sources in the relevant attainment plan.
    Comment 3.C: Regarding the State's reliance on 2024 modeling
results for its precursor analysis, CCEJN asserts that the State should
not have relied on modeling of 2024, which is after the 2023 attainment
deadline, and which nevertheless shows ammonia contributions that are
above the contribution threshold. CCEJN further asserts that the use of
2024 modeling ``violates the Act in three ways.''
    First, the commenter asserts that the approach ignores the
requirement to demonstrate attainment as expeditiously as practicable
because it does not consider ammonia reductions that may have resulted
in attainment before 2023. They note that the State claimed it was
close to attaining in 2020 and that meaningful reductions in ammonia
would have most likely resulted in attainment earlier (i.e., in 2021 or
2022).
    Second, the commenter notes that the State relies not only on a
future year but a year after the attainment deadline. Because
NOX emissions are expected to be lower in 2024 than 2023,
the commenter suggests that the impacts of ammonia reductions would be
less in 2024 than in 2023 and that the impacts of ammonia reductions in
2023 are unknown. The commenter also claims that the EPA makes
assumptions about how the State conducted its analysis and recommends
that the EPA seek clarification from the State about whether the
analysis relied on emissions projected from baseline (i.e., existing)
control measures or baseline measures plus measures committed to in the
plan. If the State did not conduct the analysis ``with numbers that are
comparable to what are expected in 2023,'' the commenter contends that
the EPA must require the State to redo the analysis.
    Third, CCEJN asserts that the State's model indicating a design
value of 12.03 [micro]g/m\3\ cannot accurately describe 2023 conditions
given that 2022 data show a design value well above 16 [micro]g/m\3\.
They conclude that the ``EPA's approval of a precursor analysis that
relies on such unrealistic modeling is therefore arbitrary and
capricious and contrary to law.''
    Response 3.C: While the State relied on 2024 modeled sensitivities
of PM2.5 to ammonia reductions, it is important to note that
the EPA also considered the 2023 model responses via a NOX-
based interpolation between the State's model results for 2020 and
2024. The highest estimated response was at the Hanford site, 0.26
[micro]g/m\3\ for 2024 and 0.27 [micro]g/m\3\ for 2023, and did not
change the EPA's conclusions regarding the ammonia precursor
demonstration.\119\ In determining that ammonia does not contribute
significantly in the San Joaquin Valley despite the Hanford response
being above the 0.25 [micro]g/m\3\ contribution threshold that the
State derived for the 1997 annual PM2.5 NAAQS, we continue
to rely on the abundant ambient evidence of excess ammonia relative to
NOX. This evidence includes evidence specific to the Hanford
area, where mobile laboratory observations during the DISCOVER-AQ study
showed ambient concentrations of ammonia that were approximately five
times higher than those that were modeled.\120\ These factors led the
EPA to conclude that the model responses were likely overestimated and
did not represent a significant contribution of ammonia to
PM2.5 levels.
---------------------------------------------------------------------------

    \119\ 88 FR 45276, 45293, fn. 184.
    \120\ Kelly, J.T. et al. (2018), op. cit.
---------------------------------------------------------------------------

    We further disagree with the commenter's assertion that the State's
approach ignores the requirement for expeditious attainment. The CAA
requirement for expeditious attainment is not directly relevant for
evaluating a precursor demonstration, which is mainly concerned with
whether PM2.5 in the atmosphere is sensitive to emissions
reductions of the precursor. For that purpose, the PM2.5
Precursor Demonstration Guidance provides for the use of modeled
sensitivities of PM2.5 to a reduction in precursor emissions
evaluated in the base year or a future year, noting that there are many
considerations in choosing the appropriate year to model.\121\ The key
factor for the State's use of a future year was the fact that sizable
NOX emissions reductions were projected to occur over time
and would change the atmospheric chemistry in the San Joaquin Valley.
The reductions are mainly due to the existing motor vehicle control
program and would occur independent of any controls in, or EPA action
on, the Plan.\122\ The sensitivity of PM2.5 concentrations
to ammonia reductions decreases with decreasing NOX
emissions. Between 2020 and 2024, the modeled response to a 30 percent
ammonia emissions reduction declines by 50 percent at the design value
monitoring site, Bakersfield-Planz, from 0.24 [micro]g/m\3\ down to
0.12 [micro]g/m\3\. (The corresponding decline is 37 percent for the
average over all monitoring sites.) Thus, much of the benefit of
ammonia controls applied in 2020 would be lost by 2023 and 2024.
---------------------------------------------------------------------------

    \121\ PM2.5 Precursor Demonstration Guidance, p. 36.
    \122\ 2018 PM2.5 Plan, Appendix B. NOX
emissions decrease 27 percent between 2020 and 2024 due to baseline
measures.
---------------------------------------------------------------------------

    With regard to whether ammonia emissions reductions could have
resulted in earlier attainment, the EPA used results from the Plan's
attainment demonstration to assess the effect of a 30 percent ammonia
reduction in 2022 and found that it would not have resulted in
attainment in that year.\123\ We estimated the 2022 design value as
15.4 [micro]g/m\3\ by using a NOX emissions-based
interpolation between the Plan's 2018 and 2023 design values, 16.3 and
14.7 [micro]g/m\3\, respectively.\124\ Similarly we estimated the 2022
sensitivity to ammonia from the State's modeled sensitivities for 2020
and 2024. Applying a 30 percent ammonia reduction for 2022 resulted in
a design value of 15.2 [micro]g/m\3\, which is above the level of the
1997 annual PM2.5 NAAQS

(i.e., 15.0 [micro]g/m\3\). Thus, we conclude that ammonia emissions
reductions would not have resulted in attainment before the Plan's
projected 2023 attainment date.
---------------------------------------------------------------------------

    \123\ Spreadsheet ``Estimated 2023 annual PM2.5
ammonia sensitivity and 2022 DV.xlsx,'' ``2023 vs. 2024 response to
30% ammonia reduction,'' EPA Region IX, October 20, 2023.
    \124\ 15 [micro]g/m\3\ SIP Revision, Appendix K, Table 33.
---------------------------------------------------------------------------

    Regarding the use of 2024 modeled sensitivities in lieu of modeled
sensitivities for 2023, the EPA finds that our conclusions would be the
same for the purposes of our evaluation of the precursor demonstration.
We estimated 2023 responses to ammonia emissions reductions by
interpolating between the responses for available 2020 and 2024
modeling; the interpolation used projected NOX emissions for
2020, 2023, and 2024 and found the estimated 2023 response to be only
0.01 [micro]g/m\3\ higher than in 2024.\125\ While there are several
differences between 2020 and 2024 modeled emissions for the various
PM2.5 precursors and direct PM2.5, the key
difference for assessing the change in the sensitivity of
PM2.5 to ammonia reductions is NOX emissions
levels. The modeling for 2020 and 2024 represent PM2.5
design values for the NOX emissions levels in 2020 and 2024,
and their respective responses to a 30 percent ammonia emissions
reduction. To estimate the PM2.5 response to ammonia
reductions in other years or for other control scenarios, only the
NOX emissions level is needed. The estimate does not depend
on NOX emissions differences between 2023 and 2024
calculated for baseline, controlled, or other scenarios, only on the
resulting 2023 emissions level being evaluated.
---------------------------------------------------------------------------

    \125\ Spreadsheet ``Estimated 2023 annual PM2.5
ammonia sensitivity and 2022 DV.xlsx,'' ``Whether 30% ammonia
reduction could attain early,'' EPA Region IX, October 20, 2023.
---------------------------------------------------------------------------

    The commenter states that it is unclear whether the precursor
demonstration analysis relied on a baseline emissions inventory, or an
inventory considering the controls in the plan. While this is not
documented prominently in the submittal materials, the precursor
demonstration modeling performed by the State used baseline
projections,\126\ that is, emissions expected with existing control
measures and without new control measures from the 2018
PM2.5 Plan or the 15 [micro]g/m\3\ SIP Revision.\127\
Notably, the EPA's conclusions for the precursor demonstration do not
depend on which of the two inventories is used. For the interpolation
to 2023, the EPA relied on controlled NOX emissions levels
(150.6 tpd) to estimate the 2023 response to 30 percent reduction to be
0.265 [micro]g/m\3\ (reported as 0.27 [micro]g/m\3\). Using baseline
NOX emissions (153.6 tpd), the estimated 2023 response is
0.275 [micro]g/m\3\, which is about 0.01 [micro]g/m\3\ higher. Thus,
the difference between using the baseline or controlled emissions for
assessing the sensitivity to ammonia emissions reductions is
negligible.
---------------------------------------------------------------------------

    \126\ 2018 PM2.5 Plan, Appendix K, Section 5.6
``PM2.5 Precursor Sensitivity Analysis'', p. 70: ``To
evaluate the impact of reducing emissions of different
PM2.5 precursors on PM2.5 DVs, a series of
model sensitivity simulations were performed, for which
anthropogenic emissions of the precursor species were reduced by a
certain percentage from the baseline emissions;'' email dated
September 19, 2019, from Jeremy Avise, CARB, to Scott Bohning, EPA
Region IX, Subject: ``FW: SJV species responses,'' with attachments,
in which the attached tables have titles like ``Difference in Annual
PM2.5 mass and species between the 2024 baseline run and
the 30% PM reduction precursor run.''
    \127\ In comparison to potential modeling of controlled
emissions, the NOX emissions for projected baseline years
2020 and 2024 are higher, ammonia would be less abundant relative to
NOX, and the responses to ammonia reductions would be
higher. Relying on baseline rather than controlled NOX
emissions levels was therefore conservative for purposes of the
ammonia precursor demonstration.
---------------------------------------------------------------------------

    Finally, the EPA disagrees that a monitored 2022 design value being
``well above'' the modeled 2023 design value invalidates the modeling
for purposes of the precursor demonstration. As discussed in the EPA's
modeling TSD for the 2018 PM2.5 Plan,\128\ the State
determined that the model performance was excellent, and the EPA found
the results to be adequate for attainment demonstration modeling. The
modeling used a 2013 base year, i.e., the specific meteorological and
emissions conditions of 2013, not those of 2022 (nor of the 2018
monitored value used in scaling the modeling results from the 2018
PM2.5 Plan). Even when the modeling itself is valid, the
model-predicted design value can differ from a recent monitored design
value due to different meteorological conditions than in 2013 base
case, emissions variability, and atypical events that affect the
monitored value, but that are not necessarily reflected in the modeling
because they are inherently unpredictable.\129\ The greater uncertainty
in the precursor demonstration, which supports the EPA's conclusion in
this final action, is that the modeling seems to conservatively
overestimate the sensitivity of PM2.5 concentrations to
ammonia reductions compared to what would be expected based on ambient
measurements of ammonia and nitrate, as discussed in Response 3A.
---------------------------------------------------------------------------

    \128\ EPA, ``Technical Support Document, EPA Evaluation of Air
Quality Modeling, San Joaquin Valley PM2.5 Plan for the
2006 PM2.5 NAAQS,'' February 2020.
    \129\ The issue of how model predictions may not match monitor
observations despite a well-performing model, and how that does not
in itself invalidate the precursor demonstration is discussed in
more detail in the EPA's proposed disapproval of the 2018
PM2.5 Plan portion addressing the 1997 annual
PM2.5 NAAQS. 86 FR 67329, 67335 (November 26, 2021).
---------------------------------------------------------------------------

    Comment 3.D: CCEJN's fourth concern with the precursor analysis is
that it believes that ``[t]he State improperly adopts a lax
contribution threshold of 0.25 [micro]g/m\3\.'' The commenter
acknowledges that the State's approach of using a 0.25 [micro]g/m\3\
threshold is consistent with the EPA's guidance but contends that the
guidance is arbitrary and capricious and that the EPA should reject it
in this rulemaking. To support their assertion, the commenter reasons
that

    [t]he result of the state's approach is that an area, like the
San Joaquin Valley, that is failing to meet multiple successively
rigorous standards for the same measurement of the same pollutant,
may need to regulate a precursor only for purposes of the more
rigorous standard. This is a senseless result because the failure to
meet an already-outdated standard only highlights the necessity of
taking all feasible regulatory steps, including regulating relevant
precursors.

    The commenter concludes that there is no advantage of two distinct
thresholds because the area will need to apply the lower threshold
eventually, and states that the ``EPA's failure to grapple with this
arbitrary result means that it has failed to provide a reasoned
explanation for its guidance, and the guidance--or at least its
application in this case--is arbitrary and capricious.'' For areas not
meeting both the 1997 and 2012 annual PM2.5 NAAQS, the
commenter proposes that the EPA should require states to apply the
threshold for the 2012 NAAQS for purposes of evaluating a precursor
contribution for both NAAQS.
    Response 3.D: The EPA disagrees that the same contribution
threshold must be used regardless of the level of the NAAQS being
examined. The EPA believes that applying a threshold that is
proportional to the level of the NAAQS is appropriate and consistent
with the Act; i.e., 0.2 [micro]g/m\3\ is appropriate for the 2012
annual PM2.5 NAAQS of 12.0 [micro]g/m\3\, and 0.25 [micro]g/
m\3\ is appropriate for the 1997 annual PM2.5 NAAQS of 15.0
[micro]g/m\3\.
    The contribution thresholds the EPA derived in the PM2.5
Precursor Demonstration Guidance represent a change in air quality that
is statistically indistinguishable from the inherent variability in the
measured atmospheric concentrations. A contribution threshold that is
proportional to, or scales with, the level of the NAAQS may also be
termed a ``relative'' approach, since the size of the threshold is
relative to the level of the NAAQS. The contribution thresholds in the
PM2.5

Precursor Demonstration Guidance were derived from a relative
variability estimate multiplied by the NAAQS level for the 2006 24-hour
PM2.5 NAAQS and 2012 annual PM2.5 NAAQS. Notably,
the PM2.5 Precursor Demonstration Guidance states: \130\
---------------------------------------------------------------------------

    \130\ PM2.5 Precursor Demonstration Guidance, p. 17,
fn. 20.

    As described in the Technical Basis Document, the monitoring
site variability is first calculated as a percentage of the measured
PM2.5. Then the median percent variability from all sites
is multiplied by the level of the NAAQS to get the threshold
concentrations. Therefore, these thresholds represent a percentage
of the 2006 24-hour NAAQS (35 [mu]g/m\3\) and the 2012 annual NAAQS
(12 [mu]g/m\3\). Different thresholds may be applicable to other
---------------------------------------------------------------------------
levels and/or forms of the NAAQS (either past or future).

    The Technical Basis Document \131\ referred to in the guidance
explains that relative variability (concentration changes as a fraction
of total concentration) was found to be more stable than absolute
variability (concentration changes in [micro]g/m\3\), and notes that
this ``indicates that a central tendency value for the relative
variability in the DV [design value]. Therefore, a representative value
can be multiplied by the level of that NAAQS to obtain a value in
concentration units ([micro]g/m\3\ for PM2.5) that is
appropriately used to characterize variability.'' \132\ The Technical
Basis Document also explains that the ``relative variability was fairly
consistent across the range of design values, suggesting a commonality
in the relative variability across a wide range of geographic regions,
chemical regimes, and baseline air quality levels.'' \133\ Thus, a
concentration amount that is relative, or proportional, to the NAAQS
level is a better basis than a fixed concentration number for
determining the size of a concentration change that is within the
inherent variability of monitored concentrations. The superiority of
the relative variability approach that was the basis of the
PM2.5 Precursor Demonstration Guidance contribution
threshold of 0.2 [micro]g/m\3\ for the 2012 annual PM2.5
NAAQS makes it appropriate to scale that value according to the NAAQS
level to arrive at 0.25 [micro]g/m\3\ for the 1997 annual
PM2.5 NAAQS.
---------------------------------------------------------------------------

    \131\ EPA, ``Technical Basis for the EPA's Development of the
Significant Impact Thresholds for PM2.5 and Ozone,'' EPA-
454/R-18-001R-18-001, EPA OAQPS, April 2018, available at https://www.epa.gov/nsr/significant-impact-levels-ozone-and-fine-particles,
https://www.epa.gov/sites/default/files/2018-04/documents/ozone_pm2.5_sils_technical_document_final_4-17-18.pdf.
    \132\ Technical Basis Document, p. 26.
    \133\ Id. at 39.
---------------------------------------------------------------------------

    Moreover, the EPA does not agree that it is arbitrary or contrary
to the Act to apply a lower contribution threshold or to potentially
regulate a precursor only for a more stringent NAAQS--it is reasonable
to expect that achieving lower PM2.5 concentrations may
require regulation of additional sources of direct PM2.5
and/or PM2.5 precursors. This is true even if an area is
nonattainment for both the higher and lower NAAQS and the EPA will
ultimately be applying the lower contribution threshold for a
subsequent plan to attain the more stringent NAAQS. Indeed, the
PM2.5 SIP Requirements Rule at 40 CFR 51.1000 defines a
precursor demonstration to mean analyses showing that precursor
emissions do not contribute significantly to PM2.5 levels
that exceed the relevant PM2.5 standard'' [emphasis added]. Applying a
lower threshold for the 1997 annual PM2.5 NAAQS because the
area is in nonattainment for a more stringent NAAQS could presume that
the modeling and precursor demonstration in a future plan will show
responses to ammonia reductions above the lower threshold and that
ammonia will be determined to be significant, such that ammonia would
need to be controlled. The EPA does not believe it is appropriate to
prejudge the analyses for a potential future plan.
4. BACM/MSM Demonstration
    Comment 4: Regarding the BACM demonstration, CCEJN notes that the
EPA's proposed approval does not address the CAA requirement for most
stringent measures (MSM), asserting that such analysis is required for
a 189(d) plan under 40 CFR 51.1010(c)(2)(i) and (c)(4), and 88 FR
45280, 45297, 45322. The commenter claims that it appears that the
State acknowledges that the MSM requirement applies in its submittal
and asserts that the EPA cannot approve the Plan until it reviews the
State's control measures under the MSM standard.
    The commenter also states that ``[t]he state's control measures
meet neither the BACM nor MSM standards.'' They note that in previous
letters to the EPA (as summarized in a previous letter attachment
included as Exhibit B), Valley groups have identified numerous
weaknesses and presented ways the District could strengthen its
regulations. The commenter asserts that the EPA's technical support
document accompanying the proposed action addresses few of these
weaknesses, and advises that ``[t]o the extent EPA has not considered
whether the suggestions in the letter constitute BACM or MSM for
purposes of the 1997 annual standard, it should do so.'' Specifically,
the commenter notes that ``[o]ne particularly glaring shortfall in the
state's submission is its failure to contain any analysis of potential
control measures to minimize soil NOX emissions,'' and
suggests that the EPA must require the State to analyze the measures in
Exhibit A to CCEJN's comment letter (citing control measures described
on pages 5 and 6), including measures to reduce soil NOX
emissions from fertilized farmlands.
    Response 4: We disagree with CCEJN's assertion that the EPA must
review the State's control measures analysis under the MSM standard. As
outlined in the PM2.5 SIP Requirements Rule, the CAA
requirement for MSM is tied to a specific trigger in the act--an
extension of the Serious area deadline under CAA section 188(e).\134\
The EPA addressed the relevance of MSM to a 189(d) plan as part of our
discussion of the control strategy for such plan in the technical
support document accompanying the final rule: \135\
---------------------------------------------------------------------------

    \134\ 81 FR 58010, 58094.
    \135\ EPA, ``Response to Comments on the Fine Particulate Matter
National Ambient Air Quality Standards: State Implementation Plan
Requirements,'' July 29, 2016.

    In addition to meeting the 5 percent emission reduction
requirement for PM2.5 or any PM2.5 plan
precursor, for any Serious nonattainment area that fails to attain
by the Serious area attainment date, the state is required to update
its control measures analysis in the section 189(d) plan. In the
event the area previously had received an extension of the Serious
area attainment date pursuant to section 188(e), the reevaluation of
control measures referenced in section 51.1010(c)(2) should include
a reevaluation of MSM. (For this reason, section 51.1010(c)(2)(i)
refers to the reevaluation of MSM ``as applicable.'') If, however,
the area did not previously request and receive an extension of the
Serious area attainment date under section 188(e), the MSM
---------------------------------------------------------------------------
requirement does not apply.

    Thus, we noted in the summary of the requirements for Serious
PM2.5 areas that fail to attain in our proposed action that
MSM is applicable only if the EPA granted an extension of the
attainment date under CAA section 188(e) for the area for the NAAQS at
issue.\136\
---------------------------------------------------------------------------

    \136\ 88 FR 45276, 45280, fn. 57.
---------------------------------------------------------------------------

    As discussed in our proposal, California's Serious area plan for
the 1997 PM2.5 NAAQS submitted in 2015 included a request
under CAA section 188(e) to extend the attainment date for the 1997
annual PM2.5 NAAQS by five years to December 31, 2020.\137\
However, after considering public comments, the EPA denied California's
request for an extension of the attainment date and subsequently
determined that the area failed to attain by the December 31, 2015
Serious area

attainment date, triggering the requirement for the 189(d) plan.
Consequently, because the San Joaquin Valley area did not receive an
extension of the Serious area attainment date under CAA section 188(e),
the MSM requirement does not apply for purposes of the 1997 annual
PM2.5 NAAQS.
---------------------------------------------------------------------------

    \137\ Id. at 45277.
---------------------------------------------------------------------------

    Regarding the commenter's claim that the State appears to
acknowledge in its submission that MSM applies, we note that the
State's controls analysis in the 2018 PM2.5 Plan was
developed to address multiple PM2.5 NAAQS, including the
2006 PM2.5 NAAQS for which the State requested an attainment
date extension under CAA section 188(e), triggering the MSM requirement
for those NAAQS. Any assertion by the State in the SJV PM2.5
Plan that a particular measure meets the MSM standard may not
necessarily indicate that the State believes that the requirement
applies for the 1997 annual PM2.5 NAAQS. Regardless,
regarding CCEJN's comment that the State's control measures do not meet
the BACM or MSM standards, given that the MSM standard does not apply
to the 1997 annual PM2.5 NAAQS, as discussed earlier in this
response, we are responding only to the commenter's assertion regarding
BACM.
    We also disagree with the commenter's assertion that the control
measures in the Plan do not meet the requirement for BACM for the 1997
annual PM2.5 NAAQS. As discussed in our proposed rule, in
our review of the State's and District's BACM demonstration, we
considered our evaluation of the State's and District's rules,
supporting information provided in the SJV PM2.5 Plan, and
our prior evaluations of the BACM and MSM demonstrations in the 2018
PM2.5 Plan for other PM2.5 NAAQS.\138\ These
prior evaluations include those to support our approval of the
demonstration for BACM (including BACT) for the 1997 24-hour
PM2.5 NAAQS,\139\ our approval of the demonstrations for
BACM and MSM for the 2006 24-hour PM2.5 NAAQS,\140\ and our
proposed disapproval of the demonstration for BACM for the 2012 annual
PM2.5 NAAQS.\141\ The EPA's prior actions for the 1997 24-
hour, 2006 24-hour, and 2012 annual PM2.5 NAAQS are relevant
to our evaluation for this final rulemaking because the State relied on
a common analysis for each of the PM2.5 standards. The EPA
conducted a thorough analysis of the State's BACM demonstration for
purposes of these prior actions, and updated the analysis for certain
source categories, as appropriate, for purposes of our proposed
approval of the BACM demonstration in the SJV PM2.5 Plan for
the 1997 annual PM2.5 NAAQS.
---------------------------------------------------------------------------

    \138\ Id. at 45305-45306.
    \139\ 87 FR 4503 (January 28, 2022).
    \140\ 85 FR 44192 (July 22, 2020).
    \141\ 86 FR 74310 (December 29, 2021).
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    Regarding the EPA's prior approval of the BACM demonstration in the
2018 PM2.5 Plan as meeting the CAA requirements for the 2006
24-hour PM2.5 NAAQS, we note that on September 17, 2020, a
group of five environmental, public health, and community groups
petitioned the Ninth Circuit Court of Appeals (``Ninth Circuit'') for
review of the EPA's final rulemaking approving the 2018
PM2.5 Plan's demonstration of BACM, BACT, and MSM for
emissions sources of direct PM2.5 and NOX for
purposes of the 2006 PM2.5 NAAQS.\142\ On April 13, 2022,
the Ninth Circuit denied the petitioners' challenge with respect to the
EPA's approval of the Plan's BACM/MSM demonstration, upholding such
approval for those NAAQS.
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    \142\ See Medical Advocates for Healthy Air v. EPA, Case No. 20-
72780, Dkt. #58-1 (9th Cir., April 13, 2022). 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.
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    Following approval of the State's BACM and MSM demonstrations for
the 2006 24-hour PM2.5 NAAQS, on December 29, 2021, the EPA
proposed to approve portions of the 2018 PM2.5 Plan as
meeting the Serious area requirements for the San Joaquin Valley for
the 2012 annual PM2.5 NAAQS, including the requirement that
the plan include BACM. However, after considering public comments, on
October 5, 2022, the EPA proposed to disapprove portions of the
District's BACM demonstration, including the evaluations of ammonia
emissions sources and building heating sources.\143\ We proposed to
disapprove the BACM demonstration for ammonia sources based in part on
our on proposed disapproval of the State's ammonia precursor analysis
for the 2012 annual PM2.5 NAAQS,\144\ as well as the State's
control measure analysis for ammonia.\145\ We proposed to disapprove
the BACM demonstration for building heating sources based on recent
control measure developments and the time horizon of the 2012 annual
PM2.5 NAAQS portion of the SJV PM2.5 Plan, which
raised questions about the feasibility of implementing additional
controls for such sources for BACM purposes in the San Joaquin
Valley.\146\ Notably, we did not re-propose action on any other
portions of the State's and District's BACM demonstration that we had
previously proposed to approve.
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    \143\ 87 FR 60494.
    \144\ Based on our proposed disapproval of the precursor
demonstration for the 2012 annual PM2.5 NAAQS, we
proposed to determine that ammonia remained a regulated precursor
for that NAAQS in the San Joaquin Valley.
    \145\ 87 FR 60494, 60509.
    \146\ Id. at 60511-60512.
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    In response to the EPA's proposed disapproval of portions of the
BACM demonstration for the 2012 annual PM2.5 NAAQS, CARB and
the District developed and submitted additional information to support
the ammonia precursor demonstration and building heating BACM
demonstration for purposes of meeting the Serious area and CAA section
189(d) requirements for the 1997 annual PM2.5 NAAQS. Our
proposal and accompanying ``Technical Support Document, San Joaquin
Valley PM2.5 Plan Revision for the 1997 Annual
PM2.5 NAAQS,'' April 2023 (``EPA's 1997 Annual
PM2.5 TSD'') summarize the additional information provided
by the State and District and the EPA's evaluation. Based on our
review, we determined that the additional information provided by the
State and District addressed the deficiencies identified in the
proposed disapproval of the 2018 PM2.5 Plan for the 2012
annual PM2.5 NAAQS as they pertained to the 1997 annual
PM2.5 NAAQS. Thus, considering our prior approvals of the
State's and District's BACM analysis for the 1997 24-hour
PM2.5 NAAQS, BACM and MSM analysis for the 2006
PM2.5 NAAQS (which was upheld by the Ninth Circuit), and the
supplemental information provided to update the SJV PM2.5
Plan based on the latest information available, we proposed to approve
the BACM demonstration for the 1997 annual PM2.5 NAAQS.
    Regarding the measures in Exhibit B to CCEJN's comment letter, the
EPA has reviewed and considered the recommendations for improvements to
the District's PM2.5 control strategy as outlined in the two
letters in Exhibit B sent by environmental groups to the EPA in 2021
\147\ and 2022.\148\ A detailed summary of our evaluation of the
feasibility of these measures, as well as numerous others, is provided
in Sections III and IV of the ``EPA Source Category and Control Measure
Assessment and Reasoned Justification

Technical Support Document'' (``Control Measure Assessment TSD'') \149\
accompanying our proposed action to promulgate a federal implementation
plan for contingency measures for the 1997 annual PM2.5
NAAQS, the 2006 24-hour PM2.5 NAAQS, and the 2012 annual
PM2.5 NAAQS.\150\ The EPA determined that the recommended
measures are either not technologically feasible or not economically
feasible within the two year timeframe for implementation as
contingency measures discussed in the EPA's draft guidance.\151\ Given
that by statute, contingency measures are additional requirements that
go beyond attainment planning requirements, and the shorter timeframe
of the attainment plan for the 1997 annual PM2.5 NAAQS
(i.e., by December 31, 2023), we similarly conclude that these measures
are not feasible for purposes of the BACM requirement for the SJV
PM2.5 Plan for the 1997 annual PM2.5 NAAQS.
---------------------------------------------------------------------------

    \147\ Letter dated October 22, 2021, from environmental
organizations to Michael S. Regan, Administrator, EPA, Subject:
``Meeting Request to Discuss PM-2.5 Crisis in the San Joaquin
Valley.''
    \148\ Letter dated May 18, 2022, from environmental
organizations to Michael S. Regan, Administrator, Environmental
Protection Agency, Subject: ``Meeting Request to Discuss PM-2.5
Crisis in the San Joaquin Valley.''
    \149\ EPA Region IX, ``EPA Source Category and Control Measure
Assessment and Reasoned Justification Technical Support Document,
Proposed Contingency Measures Federal Implementation Plan for the
Fine Particulate Matter Standards for San Joaquin Valley,
California,'' July 2023.
    \150\ 88 FR 53431 (August 8, 2023).
    \151\ EPA, Office of Air Quality Planning and Standards, Air
Quality Policy Division, ``DRAFT: Guidance on the Preparation of
State Implementation Plan Provisions that Address the Nonattainment
Area Contingency Measure Requirements for Ozone and Particulate
Matter'' (``Draft Guidance''), March 16, 2023, p. 41.
---------------------------------------------------------------------------

    Lastly, we disagree with CCEJN's assertion that the EPA must
require the State to analyze the control measures for soil
NOX emissions outlined in Exhibit A in order to approve the
BACM demonstration for the 1997 annual PM2.5 NAAQS. The EPA
previously addressed the issues of soil NOX emissions and of
analyzing potential controls for such emissions in the context of the
2018 PM2.5 Plan in 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'').\152\ More recently, the EPA also addressed the issue of
soil NOX emissions from the use of fertilizers and
pesticides in the context of our final rulemaking approving CARB's
submission of emissions inventories for VOC and NOX for the
2015 ozone NAAQS for areas in California (``2015 Ozone Inventory Final
Rule'').\153\
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    \152\ EPA's 2020 Response to Comments, pp. 148-156, Comments and
responses 6.P-1 and 6.P-2.
    \153\ 87 FR 59015 (September 29, 2022).
---------------------------------------------------------------------------

    In both the EPA's 2020 Response to Comments and the 2015 Ozone
Inventory Final Rule, the EPA acknowledged the studies cited by
commenters finding that soil NOX emissions from fertilizer
and pesticide use contribute to atmospheric NOX levels in
California.\154\ Particularly, the EPA acknowledged the growing body of
research surrounding the identification and quantification of soil
NOX emissions from fertilizer application in agricultural
soils. However, in light of the uncertainties and disagreements among
the studies regarding the contribution of fertilized cropland soils to
NOX emissions in California, the EPA found that CARB's
emissions inventories met the applicable requirements of the CAA
notwithstanding the absence of soil NOX emissions from
fertilizer or pesticide use.\155\ Furthermore, for purposes of our
final action on the San Joaquin Valley Serious Area Plan for the 2006
PM2.5 NAAQS, we determined that there was not sufficient
information available to require a controls evaluation for soil
NOX emissions for purposes of the BACM analysis for those
NAAQS.\156\
---------------------------------------------------------------------------

    \154\ Id. at 59018.
    \155\ Id. at 59018-59020.
    \156\ EPA's 2020 Response to Comments, p. 156.
---------------------------------------------------------------------------

    Upon reviewing the studies cited by CCEJN in its comment letter, we
similarly find that the information provided is not sufficient to
compel a revision to the emissions inventories in the SJV
PM2.5 Plan for the 1997 annual PM2.5 NAAQS, given
the large uncertainties in the emissions estimates. As discussed in
Response 2.A, the magnitude of soil NOX emissions varies
based on temperature; agricultural practices, such as the timing and
amount of fertilizer application and irrigation; crop type; and other
factors. Additionally, soil NOX is not directly emitted and
involves numerous natural emissions sources and processes. Thus, soil
NOX emissions are inherently difficult to estimate and
model. Likewise, given that the production of NOX in the
soil is complex, it may also be challenging to estimate the effects of
potential controls. Due to the complexity of estimating soil
NOX emissions, the partially natural source of the
emissions, and the uncertainties in the effectiveness of potential
control measures, the EPA concludes that there is not sufficient
information available at this time to warrant an evaluation of
potential controls for soil NOX emissions in the San Joaquin
Valley for purposes of the BACM analysis for the 1997 annual
PM2.5 NAAQS. We encourage CARB and the District to continue
their ongoing efforts to resolve the uncertainties in soil
NOX emissions and examine any implications for air quality
modeling and planning.
5. Public Process
    Comment 5: CCEJN asserts that the EPA must disapprove portions of
the attainment plan for the 1997 annual PM2.5 NAAQS because
the State did not provide public notice and the opportunity to comment
on portions of the Plan.
    The commenter identifies two submissions made by CARB in March 2023
and June 2023 to provide additional information relevant to the
original SIP submissions comprising the Plan: the March 2023 Ammonia
Supplement and the March 2023 Building Heating Supplement, discussing
the ammonia precursor demonstration and the BACM requirement for
building electrification, and the Title VI Supplement, addressing
necessary assurances under CAA section 110(a)(2)(E). CCEJN notes that
CAA section 110(a)(2) requires ``[e]ach implementation plan submitted
by a State under this chapter shall be adopted by the State after
reasonable notice and public hearing.'' The commenter states that the
supplements are ``required contents of such plans'' and notes that the
EPA's supplemental proposal for the 2012 annual PM2.5 NAAQS
indicated the EPA's expectation that any Title VI necessary assurances
would go through state-level notice and comment along with the
remainder of the Plan.
    Because CARB submitted these supplements directly to the EPA
without first going through additional public process and after CARB
had formally submitted the Plan, the commenter asserts that the EPA
cannot rely upon these supplements to approve the State's precursor
demonstration, BACM demonstration, or necessary assurances under CAA
section 110(a)(2)(E)(i).
    Response 5: Generally, the EPA agrees with CCEJN that SIP
submissions must meet the reasonable notice and public hearing
requirements of CAA section 110(a)(2). This is a basic requirement for
SIP submissions that appears in section 110(a)(1), section 110(a)(2),
and section 110(l), as well as EPA regulations pertaining to the
completeness of SIP submissions in 40 CFR part 51, Appendix V. However,
the EPA does not agree that this requirement necessarily applies to all
information of any type that a state may provide to the EPA. This
includes such instances as when the state is providing additional
information to supplement a SIP submission that did previously meet
notice and public hearing process

requirements, particularly when the EPA has requested that the state
provide such additional information to clarify an ambiguity in the
original SIP submission or to aid the EPA in evaluating adverse
comments raising an issue related to the original SIP submission.\157\
The EPA considers it appropriate to rely on such supplemental
information, even if it is not in the form of a formal SIP submission
that underwent full notice and public hearing process, when it expands
on and confirms information presented in the state's original SIP
submission or addresses potential deficiencies in the pre-existing
data.\158\ In such situations, the EPA considers the relevant question
to be whether the state provided reasonable notice and public hearing
with respect to the issue as part of the original SIP submission. It
would be illogical to require a state to restart the entire SIP
development process and would delay the EPA's action on a SIP
submission, thereby potentially delaying needed emissions reductions,
were the Agency to interpret CAA section 110(a)(2) notice and public
hearing requirements to apply to any and all supplemental information
provided by state. Thus, the EPA disagrees with CCEJN's assertion that
it is inappropriate for the Agency to rely on the additional
information provided by CARB in the two supplements in its analysis of
the SJV PM2.5 Plan because it would violate the requirement
under section 110(a)(2) that plans submitted to the EPA for inclusion
in the SIP must go through ``reasonable notice and public hearing.''
---------------------------------------------------------------------------

    \157\ The EPA has previously explained that it may be
appropriate to rely on a supplemental letter from a state to resolve
ambiguities in a SIP submission. See 80 FR 33840, 33888 (June 12,
2015).
    \158\ See 80 FR 33840, 33888 (``It is the EPA's practice to
neither require a state to resubmit a SIP submission nor repropose
action on the submission, so long as the clarification provided in
the interpretive letter is a logical outgrowth of the proposed SIP
provision.'').
---------------------------------------------------------------------------

    With respect to the 2023 Ammonia Supplement and the 2023 Building
Heating Supplement, the EPA believes the information contained therein
falls within the EPA's discretion to accept as a supplement, as it
expands upon and confirms information provided in the State's
previously submitted SIP submissions that did undergo the full notice
and public hearing process. CARB submitted the supplement to ``support
action on the attainment plan'' and the supplement was intended as
``clarifying information'' rather than a formal SIP revision.\159\
Also, CARB submitted this information in reaction to prior comments
related to the EPA's proposed action on the SIP submissions with
respect to the 2012 annual PM2.5 NAAQS, and in anticipation
of receiving those same comments in this action. In this respect, CARB
provided additional information that it anticipated the EPA would
request to help evaluate the issues raised in such comments.
---------------------------------------------------------------------------

    \159\ Letter dated March 29, 2023, from Steven S. Cliff,
Executive Officer, CARB, to Martha Guzman, Regional Administrator,
EPA Region 9, with enclosures.
---------------------------------------------------------------------------

    In the ammonia context, the 2018 PM2.5 Plan and 15
[micro]g/m\3\ SIP Revision present the fundamental elements of the
State's demonstration that ammonia does not contribute significantly to
exceedances of the 1997 annual PM2.5 NAAQS, including
research that supports its conclusion that ammonium nitrate
PM2.5 formation in the San Joaquin Valley is NOX-
limited rather than ammonia-limited; \160\ evidence that the area's
measures targeting VOC reductions are already reducing ammonia; \161\
and an analysis of how the District's control measures compare with
other state's rules and regulations.\162\ Upon initial review of the
State's submission, and in light of related comments received on
attainment plans for other PM2.5 NAAQS for the San Joaquin
Valley, the EPA requested clarifying information and additional
analysis to support the State's conclusions in the SJV PM2.5
Plan for the 1997 annual PM2.5 NAAQS.\163\ The information
and analysis the State provided in the March 2023 Ammonia Supplement
does not deviate from or fundamentally alter the analysis in the SJV
PM2.5 Plan; rather, it provides a wide array of potential
controls and analyses to support the fundamental conclusions in the
submitted SIP. The EPA believes that CARB provided reasonable notice
and public hearing on its position with respect to the ammonia
precursor issue in the initial SIP submission, and the additional
information in the March 2023 Ammonia Supplement merely expands upon
that position. Moreover, by taking into account the information that
CARB provided in that supplement during this rulemaking action, the EPA
itself has provided the commenters with the opportunity to address that
supplemental information now.
---------------------------------------------------------------------------

    \160\ 2018 PM2.5 Plan, Appendix G, pp. 9-10; CARB
December 2018 Staff Report, Appendix C, pp. 12-15; Attachment A to
CARB's May 9, 2019, submittal letter.
    \161\ 2018 PM2.5 Plan, Appendix C, Section C-25.
    \162\ Id.
    \163\ 40 CFR 51.1010 authorizes the EPA to require supplemental
information on potential controls when the EPA deems it necessary to
evaluate the comprehensive precursor demonstration. The regulations
and EPA guidance do not instruct on what state-level processes this
supplemental information should go through in being submitted to the
EPA. See PM2.5 Precursor Demonstration Guidance, p. 31.
---------------------------------------------------------------------------

    Similarly, the building heating BACM demonstration in the 2018
PM2.5 Plan provides the foundations and analysis for CARB's
conclusions that the State is implementing BACM with respect to
building heating appliances. As discussed in Section II.A.4, in 2020,
the EPA approved this demonstration as meeting BACM for the 2006 24-
hour PM2.5 NAAQS.\164\ However, given comments concerning
this same issue on an EPA proposal related to the 2018 PM2.5
Plan with respect to 2012 annual PM2.5 NAAQS, the EPA
requested that the State support its conclusion with more up-to-date,
additional analysis.\165\ Like the supplemental information for the
ammonia precursor demonstration, the March 2023 Building Heating
Supplement merely provides additional support for the State's original
analysis and determination that it is implementing BACM for this source
category in the San Joaquin Valley area. The EPA believes that CARB
provided reasonable notice and public hearing on its position with
respect to the building heating and electrification issue during the
development of initial SIP submission, and the additional information
in the March 2023 Building Heating Supplement merely expands upon that
position.
---------------------------------------------------------------------------

    \164\ 85 FR 44192 (July 22, 2020).
    \165\ 87 FR 60494 (October 5, 2022); Comment letter dated and
received January 28, 2022, from Brent Newell, Public Justice, et
al., to Rory Mays, EPA Region IX, 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.
---------------------------------------------------------------------------

    Thus, the EPA believes the State provided reasonable notice and
opportunity for public engagement with respect to its conclusions in
the ammonia precursor demonstration and building heating BACM elements
of the SIP and satisfied the reasonable notice and public hearing
requirements of the CAA.\166\
---------------------------------------------------------------------------

    \166\ The EPA notes that a review of the State's records
submitted with the SIP indicates that the public did identify these
two elements prior to and during the public hearing held on the
State's approval of the SIP in 2021.
---------------------------------------------------------------------------

    With respect to the Title VI Supplement, the EPA acknowledges that

it provides additional information related to an issue that the State
did not expressly address during the development of the SJV
PM2.5 Plan, i.e., the State did not previously engage in
public process specifically with respect to CAA section 110(a)(2)(E)
necessary assurances that implementation of the Plan would not be
prohibited by Title VI. However, in this instance, the issue of
necessary assurances arose in adverse comments on a related EPA
proposed action on the same 2018 PM2.5 Plan with respect to
the 2012 PM2.5 NAAQS.\167\ In order to address the concerns
raised by the commenter, the EPA sought additional information from the
State to supplement the SJV PM2.5 Plan by providing
necessary assurances and CARB provided that information in the Title VI
Supplement to do so.
---------------------------------------------------------------------------

    \167\ 86 FR 74310 (December 29, 2021). Some of the environmental
and community organizations that contributed to the adverse comments
related to necessary assurances on the EPA's proposed SIP action for
the 2012 annual PM2.5 NAAQS are among the organizations
that provided the adverse comments on the EPA's proposal for the
1997 annual PM2.5 NAAQS discussed herein.
---------------------------------------------------------------------------

    In light of prior comments, and the responsiveness of the Title VI
Supplement to the prior comments, the EPA considers it appropriate to
rely on the additional information provided by CARB in this way. Going
forward, as part of developing new SIP submissions, the EPA requests
that CARB and the District include consideration of issues related to
compliance with Title VI as part of that process, in order to ensure
public awareness and engagement. The public notice and comment process
required for development of SIP submissions provides an opportunity for
an air agency to share its position on necessary assurances publicly,
and to develop the record supporting their analysis of CAA section
110(a)(2)(E)(i) as it pertains to a particular SIP submission. Through
this process, the EPA expects states to develop adequate necessary
assurances so that they can be reviewed during the air agency-level
public comment process and subsequently by the EPA.\168\
---------------------------------------------------------------------------

    \168\ The EPA notes that the content of the Title VI Supplement
is substantially similar to recent submissions of necessary
assurances from the State on the attainment plan for the 2015 ozone
NAAQS (see ``Staff Report, CARB Review of the San Joaquin Valley
2022 Plan for the 70 ppb 8-Hour Ozone Standard'' (release date:
December 16, 2022), pp. 21-23). The plan for the 2015 ozone NAAQS,
which was submitted after the EPA's supplemental proposal on the
plan for the 2012 annual PM2.5 NAAQS, was made available
for public review during the State's public comment processes (see
CARB's ``Notice of Public Meeting to Consider Proposed San Joaquin
Valley 70 parts per billion Ozone State Implementation Plan,'' dated
December 16, 2022).
---------------------------------------------------------------------------

B. Comments From Central Valley Air Quality Coalition (CVAQ)

    Comment 6: CVAQ's comments cover many of the same issues as the
comments from CCEJN. In summary, they assert that the State's plan
``improperly relies upon faulty emission inventories and modeling data,
fails to regulate key PM2.5 precursors like ammonia and soil
NOX, does not analyze the most stringent measures needed for
attainment, and does nothing to prove State compliance with Title VI of
the Civil Rights [Act] (Title VI).'' The commenter also notes that the
two CARB-submitted supplements did not go through the State's public
process, and that the EPA had an obligation to issue a federal
implementation plan in January 2021 and has failed to do so.
    Response 6: The EPA has addressed CVAQ's concerns about the
emissions inventory and modeling data in Response 2.B; ammonia in
Responses 3.A through 3.D; soil NOX in Responses 2.A and 4;
MSM in Response 4; Title VI in Responses 1.A and 1.B, Response 5, and
in Response 7 that follows; and the State's public process in Response
5 of this document.
    Regarding the EPA's federal implementation plan (FIP) obligation,
we do not dispute that the EPA has had an obligation to implement a FIP
for the San Joaquin Valley for the 1997 annual PM2.5 NAAQS
due to a prior finding of failure to submit the required attainment
plan. As we explained in the proposed rule, as a result of the EPA's
December 6, 2018 determination effective January 7, 2019, that
California had failed to submit the required attainment plan for the
1997 annual PM2.5 NAAQS, among other required SIP
submissions for the San Joaquin Valley, the EPA became subject to a
statutory deadline to promulgate a FIP for this purpose no later than
two years after the effective date of that determination--i.e., by
January 7, 2021.\169\ However, as a result of this final rulemaking
approving all but the contingency measure requirement of the submitted
Serious area and section 189(d) plan for the 1997 annual
PM2.5 NAAQS, the only outstanding deficiency for these NAAQS
relates to contingency measures. We note that CARB has submitted three
SIP submissions to address the CAA contingency measure requirements for
the 1997 annual PM2.5 NAAQS (as well as other
PM2.5 NAAQS) in the San Joaquin Valley, including (1) the
``PM2.5 Contingency Measure State Implementation Plan
Revision,'' submitted to the EPA on June 8, 2023; \170\ (2) amendments
to District Rule 8051 (``Open Areas''), submitted to the EPA on October
16, 2023; \171\ and (3) the state-wide ``California Smog Check
Contingency Measure for the State Implementation Plan,'' submitted to
the EPA on November 13, 2023.\172\ The EPA will act on the contingency
measure SIP revisions, and/or promulgate a FIP for the contingency
measure requirement for the 1997 annual PM2.5 NAAQS and
other NAAQS, in a separate rulemaking.
---------------------------------------------------------------------------

    \169\ 88 FR 45276, 45278.
    \170\ Letter dated June 7, 2023, from Steven S. Cliff, Executive
Officer, CARB, to Martha Guzman, Regional Administrator, EPA Region
IX.
    \171\ Letter dated October 13, 2023, from Steven S. Cliff,
Executive Officer, CARB, to Martha Guzman, Regional Administrator,
EPA Region IX.
    \172\ Letter dated November 13, 2023, from Steven S. Cliff,
Executive Officer, CARB, to Martha Guzman, Regional Administrator,
EPA Region IX.
---------------------------------------------------------------------------

C. Comments From a Private Individual

    Comment 7: The private citizen commenter believes that the State's
plan contains ``aspirational and misleading `assurances' of compliance
with the Civil Rights Act'' and that the ``EPA has missed an
opportunity to live up to the commitments of the Biden administration
and EPA Administrator Regan to prioritize environmental justice and
civil rights.''
    In addition, the commenter notes the length of time that has passed
since the EPA committed to put out guidance on what would constitute
``necessary assurances'' under the Act and its failure to do so prior
to accepting the necessary assurances demonstration in the SJV
PM2.5 Plan for the 1997 annual PM2.5 NAAQS. The
commenter recommends that a simple interim guidance could include: (1)
``some sort of equity or environmental justice assessment,'' and (2)
``consideration of alternative measures to lessen or eliminate any
potentially discriminatory burdens revealed by that assessment.''
    The commenter provides a short summary of the interaction between
CAA section 110(a)(2)(E) and Title VI at the EPA, including identifying
a SIP rulemaking in 1997 where the connection between section
110(a)(2)(E) and Title VI was raised and a 2012 rulemaking pertaining
to the San Joaquin Valley on which the EPA received comments about the
same issue.
    The commenter generally recommends that the EPA exercise its
discretion in determining what constitutes necessary assurances to
require more from the State in favor of a more rigorous posture as to
what constitutes necessary assurances. In doing so, the commenter
disputes the

EPA's distinction in its proposal between necessary assurances under
CAA section 110(a)(2)(E) and a formal finding of compliance with Title
VI.
    Next, the commenter outlines the contents of CARB's Title VI
supplement. In particular, the commenter alleges that CARB's Civil
Rights and Discrimination Process does not have processes or procedures
for handling a complaint originating from outside of CARB, that the
policy has been rarely used, and was adopted prior to complaints filed
at the EPA against CARB for procedural deficiencies in the State's
policy. Additionally, the commenter believes that neither the EPA nor
CARB has demonstrated that the State's policy will be implemented in a
systemic manner to avoid disproportionate effects.
    The commenter asserts that the EPA's approval of the necessary
assurances conflates the concrete statutory requirements of Title VI
with policy-based programs and policies of environmental justice. The
commenter believes that relying on the policy-based environmental
justice initiatives does not rise to the level of the systematic and
defined methods of Title VI compliant laws.
    The commenter then describes many of the environmental justice
resources available to CARB and the EPA in developing and determining
the adequacy of necessary assurances. The commenter acknowledges that
the EPA identified many of these resources in its proposal but believes
the necessary assurances discussion should demonstrate that these
resources were considered and used in determining whether there is a
disproportionate effect in a particular SIP-based action.
    Ultimately, based on 2013 EPA guidance on compliance with CAA
section 110(a)(2)(E) and the terms of conditions under Title VI for
CARB receiving funding from the EPA, the commenter does not believe
that CARB submitted a sufficient demonstration that the required Title
VI compliance programs exist under CARB's purview. In their conclusion,
the commenter notes that the EPA could conditionally approve the Plan,
accompanied by an enforceable condition requiring CARB and the District
to bring their programs into demonstrated compliance with Title VI.
    Response 7: To the extent the comment letter is providing input to
the EPA on content for a forthcoming guidance document for CAA section
110(a)(2)(E)(i) with respect to Title VI, such considerations are
outside the scope of this action.
    As we noted in our proposal, the EPA has discretion with regard to
what may constitute necessary assurances under CAA section
110(a)(2)(E)(i). For this action, we believe the State has provided
adequate necessary assurances to support approval, under these specific
facts and circumstances. The EPA notes that what constitutes necessary
assurances for purposes of Title VI for a given SIP submission depends
upon the facts and circumstances of the Plan, and the Agency may
require more or different information as needed in other SIP actions.
This finding does not limit the Agency to review for different factors
in the future.
    Importantly, as explained in the proposal action, the EPA's
evaluation of necessary assurances pertains to CAA section
110(a)(2)(E)(i) compliance with respect to a specific SIP submission,
and not to Title VI compliance more broadly.\173\ Formal findings of
compliance with Title VI follow procedures outlined in the CFR after
administrative complaints are filed with the EPA alleging
discrimination prohibited by Title VI and the other civil rights
laws,\174\ or if the EPA initiates an affirmative compliance
review.\175\ Section 110(a)(2)(E)(i), in contrast, requires a state to
provide necessary assurances that the state's implementation of the SIP
submission at issue is not prohibited by federal law, including Title
VI. As an additional point of clarification, this necessary assurances
analysis concerning Title VI is distinct from considerations of
environmental justice more broadly. Title VI involves specific
considerations of federal law as it pertains to individuals on the
basis of race, color, or national origin. The language at issue in CAA
section 110(a)(2)(E)(i) is specific to implementation of the SIP
submissions and prohibitions under Title VI.
---------------------------------------------------------------------------

    \173\ 88 FR 45276, 45320.
    \174\ 40 CFR 7.120.
    \175\ 40 CFR 7.115.
---------------------------------------------------------------------------

    The EPA separately reviewed information related to environmental
justice considerations and those considerations are addressed in
Section IV of this document. The EPA reiterates that in our proposed
approval of the Plan, the EPA completed a Demographic Index analysis of
the area subject to the Plan, identifying environmental burdens and
susceptible populations in disadvantaged communities in the San Joaquin
Valley nonattainment area. As explained in more detail in Section
II.A.1 of this document, we believe the State has provided the
necessary assurances, including information that through its initial
implementation that the State has meaningfully considered input from
the public through public outreach that is beyond the minimum legal
requirements for public comment during SIP development, and that the
Plan submission complies with CAA section 110(a)(2)(E)(i).
    With respect to the ``EPA's processing prior (to this 2023 action
but subsequent to the 2016 policy) complaints against CARB and in which
it had noted several procedural deficiencies,'' the EPA is not aware of
any complaints filed against CARB within that time period regarding
CARB's Civil Rights and Discrimination Complaint Process, and no
complaint was specifically cited to by the commenter.\176\ The EPA
notes that it publishes all external civil rights complaints and
compliance reviews online.\177\
---------------------------------------------------------------------------

    \176\ On June 6, 2016, the EPA resolved a civil rights complaint
filed against CARB and the Bay Area Air Quality Management District.
After an investigation by the EPA's Office of Civil Rights (OCR),
the Agency found ``insufficient evidence of current non-compliance
with Title VI or EPA' s Title VI regulation'' and closed the
complaint. In the letter closing the complaint, the EPA notes that
``OCR has provided technical assistance to CARB to improve the
elements of its non-discrimination program,'' including improvements
to CARB's Civil Rights and Discrimination Complaint Process. The
closure letter specifically found ``CARB has also adopted a
grievance procedure that is contained in the Civil Rights Policy and
Discrimination Complaint Process that provides complainants a prompt
and impartial investigation of and response to complaints filed with
CARB alleging discrimination in CARB's programs or activities
prohibited by the federal non-discrimination statutes.'' The EPA
does not believe this complaint resolution and the conclusions
therein conflicts with the determinations in this final action.
https://www.epa.gov/sites/default/files/2016-06/documents/2r-00-r9_carb_resolution_letter.pdf.
    \177\ EPA, External Civil Rights Docket, https://www.epa.gov/external-civil-rights/external-civil-rights-docket-2014-present.
---------------------------------------------------------------------------

III. Motor Vehicle Emissions Budgets and Transportation Conformity

    The EPA previously determined that the 2020 and 2023 motor vehicle
emissions budgets in the 15 [micro]g/m\3\ SIP Revision were adequate
for use in transportation conformity findings. In a letter dated
February 1, 2022, the EPA notified CARB and other agencies involved in
the interagency consultation process in the San Joaquin Valley that we
had reviewed the 2020 RFP and 2023 attainment year budgets in the 15
[micro]g/m\3\ SIP Revision and found that they are adequate for
transportation conformity purposes.\178\ The EPA announced the
availability of the budgets and notified the public of the adequacy
finding via a Federal Register

notice on February 10, 2022.\179\ This adequacy finding became
effective on February 25, 2022 and the budgets have been used in
transportation conformity determinations in the San Joaquin Valley area
since that date.
---------------------------------------------------------------------------

    \178\ Letter dated February 1, 2022, from Matthew Lakin, Acting
Director, Air and Radiation Division, EPA Region IX, to Richard
Corey, Executive Officer, CARB.
    \179\ 87 FR 7834 (February 10, 2022).
---------------------------------------------------------------------------

    The EPA proposed approval of these same budgets, shown in Table 1
of this document, on July 14, 2023.180 181 The Plan
establishes separate direct PM2.5 and NOX subarea
budgets, based on EMFAC2014, for each county, and partial county (for
Kern County), in the San Joaquin Valley.\182\ The EPA discussed the
State's evaluation of the significance/insignificance factors for
ammonia, SO2, and VOC, and re-entrained road dust emissions
in the proposed rule.\183\ In this action, the EPA is finalizing
approval of the State's demonstration that emissions of ammonia,
SO2, and VOCs do not contribute significantly to
PM2.5 levels that exceed the 1997 annual PM2.5
NAAQS in the San Joaquin Valley. Therefore, consistent with the
transportation conformity regulation,\184\ motor vehicle emissions
budgets are not required for transportation-related emissions of
ammonia, SO2, and VOC for purposes of the 1997 annual
PM2.5 NAAQS in the San Joaquin Valley. In addition, since
neither the State nor the EPA has made a finding that re-entrained road
dust emissions are significant, under 40 CFR 93.103(b)(3) and
93.122(f), re-entrained road dust emissions are not required to be
included in the budgets for 1997 annual PM2.5 NAAQS in the
San Joaquin Valley.
---------------------------------------------------------------------------

    \180\ 88 FR 45276, 45322.
    \181\ The EPA did not receive any comments related to our
proposed approval of the motor vehicle emissions budgets during the
30-day comment period.
    \182\ 40 CFR 93.124(c) and (d).
    \183\ 88 FR 45276, 45316-45317.
    \184\ 40 CFR 93.102(b)(2)(v).

       Table 1--Motor Vehicle Emissions Budgets for the San Joaquin Valley for the 1997 Annual PM2.5 NAAQS
                                         [Annual average, tons per day]
----------------------------------------------------------------------------------------------------------------
                                                 2020 (RFP year)                   2023 (attainment year)
               County                ---------------------------------------------------------------------------
                                            PM2.5               NOX               PM2.5               NOX
----------------------------------------------------------------------------------------------------------------
Fresno..............................                0.9               25.3                0.8               15.1
Kern................................                0.8               23.3                0.7               13.3
Kings...............................                0.2                4.8                0.2                2.8
Madera..............................                0.2                4.2                0.2                2.5
Merced..............................                0.3                8.9                0.3                5.3
San Joaquin.........................                0.6               11.9                0.6                7.6
Stanislaus..........................                0.4                9.6                0.4                6.1
Tulare..............................                0.4                8.5                0.4                5.2
----------------------------------------------------------------------------------------------------------------
Source: 15 [micro]g/m\3\ SIP Revision, Appendix D, Table 18. Budgets are rounded up to the nearest tenth of a
  ton.

    For the reasons discussed in Sections IV.D and IV.E of the proposed
rule, the EPA is approving the attainment, RFP, and 5 percent
demonstrations, respectively, in the SJV PM2.5 Plan. The
2020 RFP and 2023 attainment year budgets are consistent with these
demonstrations, are clearly identified and precisely quantified, and
meet all other applicable statutory and regulatory requirements
including the adequacy criteria in 40 CFR 93.118(e)(4) and (5). For
these reasons, the EPA is finalizing approval of the 2020 and 2023
budgets listed in Table 1 of this document.
    The Plan also included budgets for direct PM2.5 and
NOX emissions for 2017 (RFP milestone year) and 2026 (post-
attainment quantitative milestone year). We are not approving the 2017
budgets \185\ or the post-attainment year 2026 budgets at this time.
Although the post-attainment year quantitative milestone is a required
element of the Serious area plan, it is not necessary to demonstrate
transportation conformity for 2026 or to use the 2026 budgets in
transportation conformity determinations until such time as the area
fails to attain the 1997 annual PM2.5 NAAQS. Therefore, the
EPA is not taking action on the submitted budgets for 2026 in the SJV
PM2.5 Plan at this time. However, if the EPA determines that
the San Joaquin Valley has failed to attain the 1997 annual
PM2.5 NAAQS by the applicable attainment date, the EPA would
begin the budget adequacy and approval processes under 40 CFR 93.118
for the 2026 post-attainment year budgets concurrent with such
determination that the area failed to attain.
---------------------------------------------------------------------------

    \185\ We are not approving the 2017 budgets because such budgets
would not be used in any future transportation conformity
determination because the Plan includes budgets for 2020.
---------------------------------------------------------------------------

Conformity Trading Mechanism
    Also on July 14, 2023, the EPA proposed to approve a trading
mechanism for transportation conformity analyses that would allow the
MPOs in the area to use future decreases in NOX emissions
from on-road mobile sources to offset any on-road increases in direct
PM2.5 emissions as allowed for under 40 CFR
93.124(b).186 187 As described in the proposed rule, the EPA
reviewed the trading mechanism and found it is appropriate for
transportation conformity purposes in the San Joaquin Valley for the
1997 annual PM2.5 NAAQS.\188\ The methodology for estimating
the trading ratio for conformity purposes is essentially an update
(based on newer modeling) to the State's approach, approved in the
previous plan, to model the effect of areawide direct PM2.5
and NOX emissions reductions on ambient PM2.5,
and to express the ratio of these modeled sensitivities as an inter-
pollutant trading ratio.
---------------------------------------------------------------------------

    \186\ 88 FR 45276, 45322.
    \187\ The EPA did not receive any comments related to our
proposed approval of the trading mechanism for transportation
conformity during the 30-day comment period.
    \188\ 88 FR 45276, 45318-45319.
---------------------------------------------------------------------------

    In a previous action on the 2018 PM2.5 Plan for the 2012
annual PM2.5 NAAQS, we found that the State's approach is a
reasonable method to use to develop ratios for transportation
conformity purposes and approved the 6.5 to 1 NOX to
PM2.5 trading mechanism as an enforceable component of the
transportation conformity program for the San Joaquin Valley for the
2012 PM2.5 NAAQS.\189\ Here, we similarly find that the
State's approach is reasonable and are approving the 6.5 to 1
NOX for PM2.5 trading mechanism as enforceable
components of the

transportation conformity program for the San Joaquin Valley for the
1997 annual PM2.5 NAAQS. This trading ratio replaces the 9
to 1 NOX to PM2.5 trading ratio approved for the
San Joaquin Valley for analysis years after 2014 for the 1997 annual
PM2.5 NAAQS.\190\
---------------------------------------------------------------------------

    \189\ See 86 FR 49100, 49128 (September 1, 2021) (proposed rule)
and 86 FR 67343, 67346 (November 26, 2021) (final rule).
    \190\ 76 FR 69896.
---------------------------------------------------------------------------

IV. Environmental Justice Considerations

    As described in detail in our proposal, the EPA reviewed
environmental and demographic data for the San Joaquin Valley using the
EPA's environmental justice (EJ) screening and mapping tool
(``EJSCREEN''),191 192 and compared the data to the
corresponding data for the United States as a whole. The results of the
analysis are provided for informational and transparency purposes.
---------------------------------------------------------------------------

    \191\ 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. These indicators are included in EJSCREEN reports
that are available in the rulemaking docket for this action.
    \192\ EPA Region IX, ``EJSCREEN Analysis for the Eight Counties
of the San Joaquin Valley Nonattainment Area,'' August 2022.
---------------------------------------------------------------------------

    This final action approves the State's plan for attaining the 1997
annual PM2.5 NAAQS. Information on the 1997 annual
PM2.5 NAAQS and its relationship to health impacts can be
found at 62 FR 38652 (July 18, 1997). We expect that this action and
resulting emissions reductions will generally be neutral or contribute
to reduced environmental and health impacts on all populations in the
San Joaquin Valley, including people of color and low-income
populations. At a minimum, this action would not worsen existing air
quality and is expected to ensure the area is meeting requirements to
attain and/or maintain air quality standards. Further, there is no
information in the record indicating that this action is expected to
have disproportionately high or adverse human health or environmental
effects on a particular group of people.

V. Final Action

    For the reasons discussed in this final rule, the proposed rule,
and the related technical support documents, under CAA section
110(k)(3), the EPA is approving the portions of the SJV
PM2.5 Plan as meeting CAA requirements for implementation of
the 1997 annual PM2.5 NAAQS as follows:
    (1) We are finding that the 2013 base year emissions inventories
continue to satisfy the requirements of CAA section 172(c)(3) and 40
CFR 51.1008 for purposes of both the Serious area and the CAA section
189(d) attainment plans, and to find that the forecasted inventories
for the years 2017, 2018, 2019, 2020, 2023, and 2026 provide an
adequate basis for the BACM, RFP, five percent, and modeled attainment
demonstration analyses;
    (2) We are approving the following elements as meeting the Serious
nonattainment area planning requirements:
    (a) the BACM/BACT demonstration as meeting the requirements of CAA
section 189(b)(1)(B) and 40 CFR 51.1010(a);
    (b) the demonstration (including air quality modeling) that the
Plan provides for attainment as expeditiously as practicable as meeting
the requirements of CAA sections 179(d) and 189(b) and 40 CFR
51.1011(b);
    (c) the RFP demonstration as meeting the requirements of CAA
sections 172(c)(2) and 171(1) and 40 CFR 51.1012; and
    (d) the quantitative milestone demonstration as meeting the
requirements of CAA section 189(c) and 40 CFR 51.1013;
    (3) We are approving the following elements as meeting the CAA
section 189(d) planning requirements:
    (a) the BACM/BACT demonstration as meeting the requirements of CAA
sections 189(a)(1)(C) \193\ and 189(b)(1)(B) and 40 CFR 51.1010(c);
---------------------------------------------------------------------------

    \193\ As discussed in Section III.B of the proposal, a section
189(d) plan must address any outstanding Moderate or Serious area
requirements that have not previously been approved. Because we have
not previously approved a subpart 4 RACM demonstration for the San
Joaquin Valley nonattainment area, we also proposed to approve the
BACM/BACT demonstration in the SJV PM2.5 Plan as meeting
the subpart 4 RACM/RACT requirement for the area (88 FR 45276,
45322).
---------------------------------------------------------------------------

    (b) the demonstration that the Plan will, at a minimum, achieve an
annual five percent reduction in emissions of NOX as meeting
the requirements of CAA section 189(d) and 40 CFR 51.1010(c);
    (c) the demonstration (including air quality modeling) that the
Plan provides for attainment as expeditiously as practicable as meeting
the requirements of CAA sections 179(d) and 189(d) and 40 CFR
51.1011(b);
    (d) the RFP demonstration as meeting the requirements of CAA
sections 172(c)(2) and 171(1) and 40 CFR 51.1012; and
    (e) the quantitative milestone demonstration as meeting the
requirements of CAA section 189(c) and 40 CFR 51.1013;
    (4) We are approving the motor vehicle emissions budgets for 2020
and 2023 as shown in Table 1 of this final rulemaking because they are
derived from approvable RFP and attainment demonstrations and meet the
requirements of CAA section 176(c) and 40 CFR part 93, subpart A; and
    (5) We are approving the trading mechanism provided for use in
transportation conformity analyses for the 1997 annual PM2.5
NAAQS, in accordance with 40 CFR 93.124(b).
    As discussed in Section I.B of the proposal, on November 26, 2021,
the EPA partially approved and partially disapproved portions of the
2018 PM2.5 Plan that addressed attainment of the 1997 annual
PM2.5 NAAQS in the San Joaquin Valley nonattainment area.
The elements that the EPA disapproved include the attainment
demonstration, comprehensive precursor demonstration, five percent
annual emissions reductions demonstration, BACM demonstration, RFP
demonstration, quantitative milestones, motor vehicle emissions
budgets, and contingency measures. This disapproval was effective on
December 27, 2021. In a separate final partial approval and partial
disapproval action, also effective December 27, 2021, the EPA
disapproved the contingency measure element of the 2018
PM2.5 Plan as it relates to the requirements for the Serious
area plan 2006 24-hour PM2.5 NAAQS and the Moderate area
plan for the 2012 annual PM2.5 NAAQS.\194\
---------------------------------------------------------------------------

    \194\ 86 FR 67343.
---------------------------------------------------------------------------

    In our November 26, 2021 final disapprovals, we noted that offset
and highway sanctions under CAA sections 179(b)(2) and 179(b)(1),
respectively, would not apply if California submits, and the EPA
approves, a SIP submission that corrects all of the deficiencies
identified in our final actions prior to the imposition of
sanctions.\195\ Through this final approval action, we find that
California has corrected the deficiencies associated with the Serious
area and CAA section 189(d) SIP elements for the 1997 annual
PM2.5 NAAQS for the San Joaquin Valley (except for the
contingency measures element). Thus, upon the effective date of this
final rule, all sanctions and any sanctions clocks associated with the
Serious area and CAA section 189(d) SIP elements for the 1997 annual
PM2.5 NAAQS for the San Joaquin Valley (except the
contingency measures element) will be permanently terminated.
---------------------------------------------------------------------------

    \195\ 86 FR 67329.
---------------------------------------------------------------------------

    This final action does not address the prior disapprovals of the
contingency measure elements for the 1997 annual

PM2.5 NAAQS, the 2006 24-hour PM2.5 NAAQS, and
the 2012 annual PM2.5 NAAQS. Therefore, all sanctions and
any sanctions clocks associated with the disapprovals of the
contingency measure elements for those standards will continue to apply
in the San Joaquin Valley as outlined in the November 26, 2021 final
disapprovals unless or until the EPA approves a SIP submission or
submissions meeting the outstanding contingency measure requirements
for these NAAQS. As discussed in Response 6, CARB has submitted three
SIP submissions to address the CAA contingency measure requirements for
the 1997 annual PM2.5 NAAQS, the 2006 24-hour
PM2.5 NAAQS, and the 2012 annual PM2.5 NAAQS in
the San Joaquin Valley. The EPA will act on these submissions and
determine the effects on the sanctions, if any, in accordance with 40
CFR 52.31 through one or more separate rulemaking actions.

VI. Statutory and Executive Order Reviews

    Under the Clean Air Act, the Administrator is required to approve a
SIP submission that complies with the provisions of the Act and
applicable federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a).
Thus, in reviewing SIP submissions, the EPA's role is to review state
choices, and approve those choices if they meet the minimum criteria of
the Act. Accordingly, this final action merely approves State law as
meeting federal requirements and does not impose additional
requirements beyond those imposed by State law. For that reason, this
action:
     Is not a significant regulatory action subject to review
by the Office of Management and Budget under Executive Orders 12866 (58
FR 51735, October 4, 1993) and 14094 (88 FR 21879, April 11, 2023);
     Does not impose an information collection burden under the
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact
on a substantial number of small entities under the Regulatory
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or
uniquely affect small governments, as described in the Unfunded
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have federalism implications as specified in
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not subject to Executive Order 13045 (62 FR 19885,
April 23, 1997) because it approves a State program;
     Is not a significant regulatory action subject to
Executive Order 13211 (66 FR 28355, May 22, 2001); and
     Is not subject to requirements of Section 12(d) of the
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272
note) because application of those requirements would be inconsistent
with the Clean Air Act.
    In addition, the SIP is not approved to apply on any Indian
reservation land or in any other area where the EPA or an Indian tribe
has demonstrated that a tribe has jurisdiction. In those areas of
Indian country, the rule does not have tribal implications and will not
impose substantial direct costs on tribal governments or preempt tribal
law as specified by Executive Order 13175 (65 FR 67249, November 9,
2000).
    Executive Order 12898 (Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations, 59 FR 7629,
Feb. 16, 1994) directs federal agencies to identify and address
``disproportionately high and adverse human health or environmental
effects'' of their actions on minority populations and low-income
populations to the greatest extent practicable and permitted by law.
The EPA defines environmental justice (EJ) as ``the fair treatment and
meaningful involvement of all people regardless of race, color,
national origin, or income with respect to the development,
implementation, and enforcement of environmental laws, regulations, and
policies.'' The EPA further defines the term fair treatment to mean
that ``no group of people should bear a disproportionate burden of
environmental harms and risks, including those resulting from the
negative environmental consequences of industrial, governmental, and
commercial operations or programs and policies.''
    The State did not evaluate environmental justice considerations as
part of its SIP submittal; the CAA and applicable implementing
regulations neither prohibit nor require such an evaluation. The EPA's
evaluation of environmental justice is described in the section of this
document titled, ``Environmental Justice Considerations.'' The analysis
was done for the purpose of providing additional context and
information about this rulemaking to the public, not as a basis of the
action. Due to the nature of the action being taken here, this action
is expected to have a neutral to positive impact on the air quality of
the affected area. In addition, there is no information in the record
upon which this decision is based that is inconsistent with the stated
goal of E.O. 12898 of achieving environmental justice for people of
color, low-income populations, and Indigenous peoples.
    This action is subject to the Congressional Review Act, and the EPA
will submit a rule report to each House of the Congress and to the
Comptroller General of the United States. This action is not a ``major
rule'' as defined by 5 U.S.C. 804(2).
    Under section 307(b)(1) of the Clean Air Act, petitions for
judicial review of this action must be filed in the United States Court
of Appeals for the appropriate circuit by February 12, 2024. Filing a
petition for reconsideration by the Administrator of this final rule
does not affect the finality of this action for the purposes of
judicial review nor does it extend the time within which a petition for
judicial review may be filed, and shall not postpone the effectiveness
of such rule or action. This action may not be challenged later in
proceedings to enforce its requirements. (See section 307(b)(2).)

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by
reference, Particulate matter, Reporting and recordkeeping
requirements.

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

    Dated: December 5, 2023.
Martha Guzman Aceves,
Regional Administrator, Region IX.

    Part 52, chapter I, title 40 of the Code of Federal Regulations is
amended as follows:

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

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

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

Subpart F--California

0
2. Section 52.220 is amended by adding paragraphs (c)(537)(ii)(A)(9)
and (10) and (c)(537)(ii)(B)(7), (8), and (9) to read as follows:

Sec.  52.220  Identification of plan--in part.

* * * * *
    (c) * * *
    (537) * * *
    (ii) * * *
    (A) * * *
    (9) CARB Resolution No. 21-21, September 23, 2021, submitted as a
revision to the 2018 PM2.5 Plan on

November 8, 2021, by the Governor's designee.
    (10) ``Staff Report, Proposed SIP Revision for the 15 [mu]g/m\3\
Annual PM2.5 Standard for the San Joaquin Valley,'' August
13, 2021, submitted as a revision to the 2018 PM2.5 Plan on
November 8, 2021, by the Governor's designee.
    (B) * * *
    (7) 2018 Plan for the 1997, 2006, and 2012 PM2.5
Standards (``2018 PM2.5 Plan''), adopted November 15, 2018
(portions pertaining to the 1997 annual PM2.5 NAAQS only,
and excluding Chapter 4 (``Attainment Strategy for PM2.5''),
Chapter 5 (``Demonstration of Federal Requirements for 1997
PM2.5 Standards''), Chapter 6 (``Demonstration of Federal
Requirements for 2006 PM2.5 Standards''), Chapter 7
(``Demonstration of Federal Requirements for 2012 PM2.5
Standards''), Appendix D (``Mobile Source Control Measure Analyses''),
Appendix H (``RFP, Quantitative Milestones, and Contingency''), and
Appendix K (``Modeling Attainment Demonstration'')).
    (8) ``Attainment Plan Revision for the 1997 Annual PM2.5
Standard,'' August 19, 2021, excluding Appendix H, section H.3
(``Contingency Measures''), submitted as a revision to the 2018
PM2.5 Plan on November 8, 2021, by the Governor's designee.
    (9) SJVUAPCD Governing Board Resolution No. 21-08-13, August 19,
2021, submitted as a revision to the 2018 PM2.5 Plan on
November 8, 2021, by the Governor's designee.
* * * * *

0
3. Section 52.237 is amended by revising paragraph (a)(11) to read as
follows:

Sec.  52.237  Part D disapproval.

    (a) * * *
    (11) The contingency measures portion of the 2018 Plan for the
1997, 2006, and 2012 PM2.5 Standards (``2018
PM2.5 Plan''), adopted November 15, 2018, are disapproved
for San Joaquin Valley with respect to the 1997 annual PM2.5
NAAQS because they do not meet the requirements of Part D of the Clean
Air Act.
* * * * *

0
4. Section 52.244 is amended by adding paragraph (f)(4) to read as
follows:

Sec.  52.244  Motor vehicle emissions budgets.

* * * * *
    (f) * * *
    (4) San Joaquin Valley, for the 1997 annual PM2.5 NAAQS
only (years 2020 and 2023 budgets only), approved January 16, 2024.

[FR Doc. 2023-27088 Filed 12-13-23; 8:45 am]
BILLING CODE 6560-50-P