```

[Federal Register Volume 90, Number 12 (Tuesday, January 21, 2025)]
[Rules and Regulations]
[Pages 6823-6827]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-01110]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R09-OAR-2023-0448; FRL-11677-03-R9]

Approval and Promulgation of Implementation Plans; State of 
California; Coachella Valley; Extreme Attainment Plan for 1997 8-Hour 
Ozone Standards

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Environmental Protection Agency (EPA) is taking final 
action to approve elements of a state implementation plan (SIP) 
submittal from the State of California to meet Clean Air Act (CAA) 
``Extreme'' nonattainment area requirements for the 1997 8-hour ozone 
national ambient air quality standards (NAAQS) in the Riverside Co. 
(Coachella Valley), CA nonattainment area (``Coachella Valley''). We 
are specifically approving the reasonable further progress (RFP) 
demonstration and the vehicle miles traveled demonstration.

DATES: This rule is effective February 20, 2025.

ADDRESSES: The EPA has established a docket for this action under 
Docket ID No. EPA-R09-OAR-2023-0448. All documents in the docket are 
listed on the https://www.regulations.gov website. Although listed in 
the index, some information is not publicly available, e.g., 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Certain other material, such as 
copyrighted material, is not placed on the internet and will be 
publicly available only in hard copy form. Publicly available docket 
materials are available through https://www.regulations.gov, or please 
contact the person identified in the FOR FURTHER INFORMATION CONTACT 
section for additional availability information. If you need assistance 
in a language other than English or if you are a person with a 
disability who needs a reasonable accommodation at no cost to you, 
please contact the person identified in the FOR FURTHER INFORMATION 
CONTACT section.

FOR FURTHER INFORMATION CONTACT: Tom Kelly, Geographic Strategies and 
Modeling Section (AIR-2-2), EPA Region IX, 75 Hawthorne Street, San 
Francisco, CA 94105; phone: (415) 972-3856; or email: 
[email protected].

SUPPLEMENTARY INFORMATION: Throughout this document, ``we,'' ``us,'' 
and ``our'' refer to the EPA.

Table of Contents

I. Proposed Action
II. Public Comments and the EPA's Responses
III. The EPA's Action
IV. Statutory and Executive Order Reviews

I. Proposed Action

A. Summary

    On April 16, 2024,\1\ the EPA proposed to approve two SIP 
submittals from the South Coast Air Quality Management District (SCAQMD 
or ``District'') and the California Air Resources Board (CARB) 
addressing the Extreme area planning requirements for the 1997 ozone 
NAAQS in Coachella Valley. The first submittal, the ``Final Coachella 
Valley Extreme Area Plan for the 1997 8-Hour Ozone Standard'' 
(``Coachella Valley Ozone Plan'' or ``Plan''),\2\ was prepared by the 
SCAQMD and submitted by CARB on December 29, 2020.\3\ We proposed to 
approve all elements of the Plan except the reasonably available 
control technology (RACT) demonstration, which we plan to address in a 
subsequent rulemaking. The second submittal, the ``2020 Coachella 
Valley Vehicle Miles Traveled Emissions Offset Demonstration'' (``VMT 
Offset Demonstration''),\4\ was prepared by CARB and submitted on March 
18, 2021.\5\ We proposed to approve the entire VMT Offset 
Demonstration. Our proposed action contains more information on the two 
submittals and our evaluation.
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    \1\ 89 FR 26817.
    \2\ SCAQMD, ``Final Coachella Valley Extreme Area Plan for the 
1997 8-Hour Ozone Standard,'' December 2020.
    \3\ Letter dated December 28, 2020, from Richard W. Corey, 
Executive Officer, CARB, to John W. Busterud, Regional 
Administrator, EPA Region 9 (submitted electronically December 29, 
2020).
    \4\ CARB, Staff Report, ``2020 Coachella Valley Vehicle Miles 
Traveled Emissions Offset Demonstration,'' release date January 22, 
2021.
    \5\ Letter dated March 15, 2021, from Richard W. Corey, 
Executive Officer, CARB, to Deborah Jordan, Acting Regional 
Administrator, EPA Region 9 (submitted electronically March 18, 
2021).
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    On June 12, 2024, we finalized our proposed action on certain 
portions of the Coachella Valley Ozone Plan.\6\ Specifically, we 
finalized approval of the reasonably available control measures 
demonstration, the attainment demonstration, and the State's 
demonstration that it has satisfied the clean fuels for boilers 
requirement for the Coachella Valley nonattainment area. Our June 12, 
2024, notice stated that we intended to take final action on the 
remaining VMT Offset Demonstration and RFP demonstration in a future 
rulemaking. We are finalizing approval of these elements in this 
notice.
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    \6\ 89 FR 49815.
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B. Correction

    In summarizing the State's photochemical modeling and the 
associated control measures, the EPA's proposed rule incorrectly stated 
that the Coachella Valley control strategy for the 1997 ozone NAAQS 
relies on aggregate emissions reduction commitments from the ``Final 
2016 Air Quality Management Plan'' (``2016 AQMP'').\7\ While the 
Coachella Valley Ozone Plan discusses rules addressing the area's 
progress related to commitments needed for the area to meet the 2008 
ozone NAAQS by 2026, the emissions reductions associated with these 
rules are not reflected in the area's inventory, and the Plan does not 
rely on the commitments to attain the 1997 ozone NAAQS in 2023.\8\
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    \7\ 89 FR 26817, 26826.
    \8\ See Coachella Valley Ozone Plan, pp. 4-4 through 4-17.
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II. Public Comments and the EPA's Responses

    The EPA's proposed action provided a 30-day public comment period. 
During this period, we received comments from Air Law for All (ALFA), 
dated May 16, 2024. These comments relate to our proposed action on the 
RFP demonstration. No comments were received on other parts of the 
proposal. The comments are summarized and addressed below.

[[Page 6824]]

    Comment #1: ALFA criticizes the EPA's proposal to decline to act on 
the area's contingency measures and new source review (NSR) submittals 
for the 1997 ozone NAAQS. The commenter argues that the EPA lacks 
discretion to act on selected portions of submittals when the 18-month 
statutory deadline for action has passed. The commenter states that CAA 
section 110(k) does not explicitly grant the EPA authority to act on 
selected portions of submittals, and argues that when an agency 
exercises discretion, it must give permissible reasons for doing so. 
The commenter asserts that the EPA has not given a permissible reason 
for acting on only portions of the submittal and speculates that the 
EPA has done so only to delay disapproval of the provisions and avoid 
starting the associated sanctions and federal implementation plan 
clocks. The commenter also points out that the EPA noted in the 
proposal that the State has not yet submitted certain required portions 
of the plan, and states that EPA has not offered an explanation for not 
making a finding of failure to submit for those missing portions of the 
attainment plan.
    Response to Comment #1: As a general matter, comments regarding SIP 
elements not addressed in the proposed rule are outside the scope of 
this action. The EPA intends to address all required planning elements 
for the Coachella Valley for the 1997 ozone NAAQS in subsequent 
actions.\9\
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    \9\ For example, in addition to the contingency measures 
submittal noted previously, the EPA recently received the State's 
submittal to address the fee requirements of CAA section 185 for the 
Coachella Valley. Letter from Steven S. Cliff, CARB, to Martha 
Guzman, EPA, dated August 9, 2024, and submitted electronically on 
August 13, 2024.
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    While the EPA has a statutory deadline by which to act on all SIP 
submittals under CAA section 110(k)(2), the EPA is not obligated to act 
on all SIP submittals or all SIP elements for a nonattainment area in 
the same action. The EPA routinely takes separate actions on submittals 
or portions of submittals that address unique CAA requirements.\10\ The 
EPA strives to meet all statutory deadlines; however, the EPA 
acknowledges that we are sometimes delayed due to resource limitations 
and other practical constraints.
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    \10\ See, e.g., 85 FR 8181 (February 13, 2020), 85 FR 11817 
(February 27, 2020) (acting separately on Imperial Valley RACT 
element and ozone plan, respectively, for the 2008 ozone NAAQS).
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    With respect to the Coachella Valley contingency measures, the EPA 
notes that CARB and the SCAQMD previously made a submittal addressing 
the contingency measures requirement for the 1997 ozone NAAQS that was 
subsequently withdrawn,\11\ and the EPA has no obligation to act on 
withdrawn submittals. The EPA's current approach for evaluating 
contingency measures submittals has been shaped by several recent court 
decisions.\12\ In response to these decisions, the EPA has issued the 
draft guidance cited in our proposed action, titled ``DRAFT: Guidance 
on the Preparation of State Implementation Plan Provisions that Address 
the Nonattainment Area Contingency Measure Requirements for Ozone and 
Particulate Matter.'' \13\ Following our issuance of this draft 
guidance document, the District and CARB submitted Coachella Valley 
contingency measures for the 1997 ozone NAAQS to the EPA on April 3, 
2024. The EPA notes that the statutory deadline to act on that 
submittal under CAA section 110(k)(2) has not yet passed.
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    \11\ Contingency measures were submitted on November 28, 2007, 
in the SCAQMD ``Final 2007 Air Quality Management Plan,'' 
transmitted to the EPA in a letter from James N. Goldstene, CARB, to 
Wayne Nastri, EPA, and withdrawn by the District, in a letter dated 
April 7, 2020, from Wayne Nastri, SCAQMD to Richard Corey, CARB, and 
withdrawn by CARB in a letter dated April 28, 2020, from Richard 
Corey, CARB, to John W. Busterud, EPA.
    \12\ See esp. Bahr v. EPA, 836 F.3d 1218 (9th Cir. 2016); Sierra 
Club v. EPA, 21 F.4th 815 (D.C. Cir. 2021); Association of Irritated 
Residents v. EPA, 10 F.4th 937 (9th Cir. 2021).
    \13\ 88 FR 17571 (March 23, 2023).
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    Comment #2: ALFA comments that the submittal fails to show that the 
substitute NOX emissions reductions will ``result in a 
reduction of ozone concentrations at least equivalent'' to the required 
3 percent per annum VOC emissions reductions, and that as a result, the 
EPA's proposed approval is arbitrary and capricious and contrary to 
law. The commenter describes the relative roles of VOC and 
NOX in ozone formation, including the existence of an 
``optimum'' VOC to NOX ratio for a given level of VOC (i.e., 
a NOX concentration at which the maximum amount of ozone is 
produced). As explained by the commenter, in a ``NOX 
saturated'' situation where NOX levels exceed this optimum 
ratio, a reduction in NOX levels can lead to increases in 
ozone levels, and in a ``NOX limited'' situation with 
NOX levels below the optimum ratio, VOC reductions toward 
the optimum ratio may have little effect on ozone levels. As a result, 
the commenter says, ozone response to precursor control can vary 
greatly between areas. The commenter argues that language in the CAA, 
including CAA sections 185B, 182(f), and 182(c)(2)(C), indicates that 
Congress was aware of these issues, including that in some scenarios 
NOX reductions may not decrease ozone concentrations.
    The commenter also points to the EPA's consideration of the 
relative effectiveness of NOX and VOC controls for 
interpollutant offset trading under the new source review (NSR) 
permitting program and in applying requirements for major stationary 
sources of VOC to NOX sources under CAA 182(f), noting that 
in these situations EPA guidance indicates that photochemical grid 
modeling of multiple scenarios should be conducted to support 
demonstrations related to the relative effectiveness of controls. 
Through these comparisons, the commenter suggests that the Coachella 
Valley submittal should have included similar photochemical grid 
modeling to determine whether the substitute NOX emissions 
reductions result in equivalent ozone reductions.
    While acknowledging that ozone isopleths, which are graphs of ozone 
levels resulting from various levels of emissions reductions for each 
monitoring station, are a technically sound method of comparing the 
relative benefits of reducing NOX and VOC emissions, the 
commenter states that the EPA's overall analysis is insufficient and 
that there are missing steps in going from isopleths to a justification 
for the percentage method in the NOX Substitution Guidance. 
The commenter states, ``if EPA plans to rely on the isopleths'' as the 
justification for NOX substitution, ``EPA must re-propose 
its action with an explanation that is reasonably detailed enough for 
the public to be able to comment on it.'' The commenter further states 
that CAA section 182(c)(2)(C)'s use of the plural ``ozone 
concentrations'' means that an equivalency demonstration at a single 
monitoring site would be contrary to the CAA and argues that Congress 
intended the equivalence requirement to apply throughout the 
nonattainment area.
    Response to Comment #2: We disagree with the commenter's 
characterization of the District's submittal and the EPA's proposed 
approval. As described further in this document, the EPA concludes that 
the analysis included with the modeling and control strategy in the 
Coachella Valley Ozone Plan adequately demonstrates that plan 
reductions of VOC and NOX would result in a reduction in 
ozone concentrations at least equivalent to that resulting from VOC 
emissions reductions. This condition is required under CAA 182(c)(2)(C) 
for substituting NOX reductions for VOC reductions. We 
therefore conclude that the District's use of NOX 
substitution in the RFP demonstration for the Coachella Valley is 
appropriate in this circumstance.

[[Page 6825]]

    One factor, not discussed in the Coachella Valley Ozone Plan, that 
contributes to the NOX-limited conditions is biogenic VOC 
emissions from vegetation. Biogenic VOC emissions are not required to 
be reported in nonattainment area inventories. Biogenic emissions are, 
however, included in the inventory used to model attainment in the 
Plan, and do contribute to the formation of ozone in the area. The most 
recent National Emissions Inventory estimates that biogenic VOC 
emissions represent more than 37 percent of VOC emissions in Riverside 
County.\14\ California's statewide estimate for biogenic VOC emissions 
represents nearly 43 percent of the total VOC inventory. Biogenic 
NOX, in comparison, represent only 3.4 percent of Riverside 
County NOX emissions and 7.7 percent of statewide 
NOX.\15\ Because biogenic VOC is such a large portion of the 
inventory, reducing anthropogenic VOC emissions represents a smaller 
reduction in total VOC than a corresponding reduction of anthropogenic 
NOX compared to total NOX reductions.\16\ When 
biogenic emissions are taken into account, the amount of NOX 
relative to VOC is smaller, tending to make the ozone chemistry more 
NOX-limited. That is, reductions of NOX are even 
more effective than VOC reductions at reducing ozone, and appropriate 
to substitute for VOC reductions to achieve equivalent ozone 
concentration reductions.
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    \14\ See file titled ``D.1.a. Riverside NOX & VOC 
Emissions.xlsx'' in the docket for this rulemaking, which displays 
information from the EPA's Emissions Inventory Gateway (https://www.epa.gov/air-emissions-inventories/emissions-inventory-system-eis-gateway).
    \15\ Id.
    \16\ Wildfire emissions are a large source of NOX 
emissions and are included the model evaluation but are not factored 
into the base and future year attainment modeling. Additionally, the 
influence of wildfire can be excluded from an EPA attainment finding 
as an exceptional event, in accordance with the EPA's Exceptional 
Events Rule 81 FR 68216 (October 3, 2016).
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    The Coachella Valley Ozone Plan provides ample documentation that 
the transport of ozone and ozone precursors in the South Coast Air 
Basin is the primary cause of high ozone concentrations in the 
Coachella Valley, such as the correlation between the annual number of 
exceedance days for the two areas.\17\ The Plan relies on upwind 
reductions within the South Coast Air Basin, where NOX and 
VOC emissions are respectively more than 20 and nearly 27 times larger 
than those within Coachella Valley.\18\ By the time ozone precursors 
have been transported to the Coachella Valley, NOX has been 
preferentially removed by chemical and physical processes.\19\ At the 
same time, there are fewer NOX emissions and more biogenic 
VOC emissions in moving from the more developed Los Angeles urban area 
to the more rural Coachella area. This leaves less NOX 
available to form ozone, creating a NOX-limited condition 
where NOX emissions reductions are more effective than VOC 
emissions reductions at decreasing ozone concentrations.
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    \17\ Coachella Valley Ozone Plan, p. 2-3, figure 2-3.
    \18\ 2018 Coachella Valley Ozone Plan, p. 3-6, table 3-3.
    \19\ The VOC:NOX ratio increases due to chemical 
conversion to HNO3 and due to the process of deposition 
to surfaces, which removes NOX (in the form of 
HNO3) from the air more quickly than VOC. Barbara J. 
Finlayson-Pitts and James N. Pitts Jr., 1993, ``Atmospheric 
Chemistry of Tropospheric Ozone Formation: Scientific and Regulatory 
Implications,'' Journal of the Air and Waste Management Association, 
43:8, 1091-1100, https://doi.org/10.1080/1073161X.1993.10467187.
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    The isopleth diagrams in the Coachella Valley Ozone Plan show that 
NOX reductions are more effective than VOC reductions at 
decreasing ozone across a wide range of VOC emissions quantities, which 
is all that is needed to show that substitution on a 1-1 basis yields a 
reduction in ozone concentrations at least equivalent to the required 
VOC reductions.\20\ The District generated these diagrams by using 
photochemical grid modeling to simulate various combinations of 
NOX and VOC emissions reductions and then plotting the 
resulting ozone concentrations for the monitor. Thus, while the 
commenter suggests that the submittal should have included 
photochemical modeling, that modeling is the basis of the analysis 
already provided in the form of the isopleth diagrams. The isopleth 
diagrams have VOC emissions on the horizontal x-axis and NOX 
emissions on the vertical y-axis. Isopleth lines represent the ozone 
concentration at different levels of VOC and NOX emissions, 
and a 45-degree line sloping from upper left to lower right would 
indicate that NOX and VOC emissions reductions are equally 
effective at reducing ozone concentrations.
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    \20\ The isopleths include biogenic VOCs in the analysis as 
constant values, showing changes only to anthropogenic emissions.
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    For the Palm Springs monitor, which is the only monitor in the 
Coachella Valley exceeding the 1997 ozone NAAQS, the diagram shows 
nearly horizontal isopleth lines.\21\ This indicates a very small ozone 
response to VOC reductions, so that ozone formation in the Palm Springs 
area is much more responsive to NOX emissions reductions 
than to VOC reductions. The 2016 AQMP's isopleth for Indio-Jackson 
Street monitor near the center of the nonattainment area shows a 
similarly flat slope.\22\
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    \21\ Coachella Valley Ozone Plan, p. 5-8, Figure 5-5. See also 
89 FR 26817, 26826 (citing isopleth and surrounding discussion).
    \22\ 2016 AQMP, appendix V, Attachment 5, page 10.
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    In other words, the graphs show that when NOX emissions 
are reduced, the level of ozone decreases substantially, and that, in 
contrast, reducing the level of VOC emissions results in much less 
reduction in the level of ozone. The curve of the line on the graphs 
indicates that reductions in NOX emissions will be 
considerably more effective than VOC reductions in reducing ozone 
concentrations on both a mass and percentage basis, and that VOC 
reductions will achieve only minor reductions in ozone concentrations 
even under scenarios involving large VOC reductions relative to current 
levels. Because NOX reductions are more effective than VOC 
reductions at reducing ozone concentrations, the Plan's NOX 
to VOC substitution ratio of one to one (equivalent on a percentage 
basis) is a conservative way to determine the amount of NOX 
reductions needed to replace VOC emissions reductions and result in at 
least an equivalent ozone decrease in ozone concentration as required 
under CAA section 182(c)(2).
    In fact, the isopleths show that a given percentage of 
NOX reductions provide more of a reduction in ozone 
concentration than the same percentage of VOC reductions.\23\ Thus, the 
Plan's NOx to VOC substitution ratio of one to one is an appropriate 
ratio here and the analysis is not missing steps, as the commenter has 
alleged. As explained, the isopleths for the two Coachella Valley 
monitoring sites (Indio-Jackson Street and Palm Springs-Fire Station) 
show that ozone concentrations are more sensitive to reductions in 
NOX than reductions in VOC across a wide range of VOC 
emissions quantities. In addition, the Plan provides multiple lines of 
evidence to support its statement that ``ozone concentration in Palm 
Springs is much more sensitive to changes in NOX emissions 
than to changes in VOC emissions and indicates that NOX 
emission reduction is key for ozone attainment in the Coachella 
Valley.'' \24\ Thus, as the Coachella Valley Ozone Plan's modeling and 
control strategy demonstrates, NOX reductions are more 
effective than VOC reductions in reducing ozone concentration for this

[[Page 6826]]

area based on a one to one substitution ratio, and the underlying 
requirement in CAA section 182(c)(2)(C) has been met.
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    \24\ Id.
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    The EPA disagrees with the commenter's suggestion that our approval 
relies on demonstration of equivalence at a ``a single monitoring 
site'' and is therefore contrary to the CAA. As explained in this 
notice, this demonstration includes the analysis of isopleth graphs for 
both the Palm Springs-Fire Station and Indio-Jackson Street monitoring 
sites, which are the only two monitoring sites in the Coachella Valley 
nonattainment area. Moreover, the EPA disagrees that CAA section 
182(c)(2)(C)'s use of the term ``ozone concentrations'' warrants the 
narrow interpretation that equivalence must be specifically 
demonstrated throughout a nonattainment area. As an initial matter, we 
note that the Act commonly uses the term ``concentrations'' to refer 
generally to ambient pollution levels at one or more (but not 
necessarily multiple) monitors or locations.\25\ CAA section 
182(c)(2)(C) grants the EPA discretion to define the conditions under 
which NOX reductions may be substituted for or combined with 
VOC reductions ``in order to maximize the reduction in ozone air 
pollution'' and does not further specify the conditions that represent 
an ``equivalent'' reduction in ozone; for instance, it does not require 
a specific concentration test at every monitor or at specific locations 
within an area.\26\ No such requirement appears in the Act's other 
provisions governing the RFP demonstration, which define specific 
percentage reductions aimed at ensuring timely attainment of the 
NAAQS,\27\ or in the EPA's 1993 NOX Substitution Guidance, 
which describes a recommended procedure for states to follow to utilize 
NOX substitution.\28\ We interpret CAA section 182(c)(2)(C) 
and these supporting authorities as properly reflecting Congress' 
intent to allow NOX reductions to be considered to 
substitute for the required VOC reductions so long as these reductions 
are at least as effective in reducing ozone concentrations and 
consistent with the area's demonstration of timely attainment.\29\
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    \25\ E.g., CAA section 107(e)(2); CAA section 110(a)(5)(D).
    \26\ NOX Substitution Guidance, Office of Air Quality 
Planning and Standards, U.S. Environmental Protection Agency, 
December 1993, available at https://archive.epa.gov/ttn/ozone/web/html/index-13.html.
    \27\ E.g., CAA 182(b)(1) and (c)(2)(B); see also CAA 171(1) 
(defining RFP as ``such annual incremental reductions in emissions 
of the relevant air pollutant as are required by this part or may 
reasonably be required by the Administrator for the purpose of 
ensuring attainment of the applicable national ambient air quality 
standard by the applicable date'').
    \28\ NOX Substitution Guidance, Office of Air Quality 
Planning and Standards, U.S. Environmental Protection Agency, 
December 1993.
    \29\ See id. at 8 (quoting H. Rept. No. 490, 101st Cong., 2d 
Sess. 239 (1990)) (``NOX reductions may not be 
substituted for VOC reductions in a manner that delays attainment of 
the ozone standard or that results in lesser annual reductions in 
ozone concentration than provided for in the attainment 
demonstration.'').
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    Further, we believe that the commenter's comparison to the EPA's 
requirements and recommendations for interpollutant trading and 
exemption from NOX requirements under CAA 182(f) 
misunderstands the purpose of and requirements for NOX 
substitution under CAA 182(c)(2)(B) relative to these other examples. 
First, interpollutant trading is no longer allowed for ozone.\30\ 
Second, the guidance documents cited by the commenter for these 
examples are non-binding and do not constrain the EPA's discretion to 
adopt a different approach where appropriate.\31\ The documents 
recommend photochemical grid modeling in some scenarios but do not 
require this approach or any other specific demonstration. This 
reflects the EPA's acknowledgement that the level of analysis required 
for any particular demonstration related to NOX and VOC 
reductions will differ based on context and local conditions, such as 
those noted by the commenter regarding the relative effectiveness of 
controlling each. In the context of CAA 182(c)(2)(C), in an area where 
isopleths generated through photochemical grid modeling and 
accompanying analysis indicate that the VOC reductions required under 
CAA 182(c)(2)(B) will be less effective for reducing ozone 
concentrations than a corresponding percentage reduction in 
NOX emissions, no additional modeling or demonstration is 
required.
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    \30\ See 86 FR 37918, 37923-24 (July 19, 2021).
    \31\ See EPA, ``Guideline for Determining the Applicability of 
Nitrogen Oxide Requirements under Section 182(f)'' (December 16, 
1993), 1; Memorandum dated January 14, 2005, from Stephen D. Page, 
Director, Office of Air Quality Planning and Standards, U.S. EPA, to 
EPA Regional Air Directors, Regions I-X, Subject: ``Guidance on 
Limiting Nitrogen Oxides (NOX) Requirements Related to 8-
Hour Ozone Implementation,'' 3; EPA-454/R-18-004, ``Technical 
Guidance for Demonstration of Inter-Precursor Trading (IPT) for 
Ozone in the Nonattainment New Source Review Program,'' Office of 
Air Quality Planning and Standards (May 2018) (``IPT Guidance''), 2. 
The IPT Guidance specifically excludes applicability to RFP 
demonstrations. IPT Guidance at 2, n.1.
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    For the reasons described herein, the EPA disagrees that additional 
justification is needed to show that equal percentage reductions of 
NOX emissions can substitute for VOC emissions to meet the 
CAA requirements for RFP in this context. We find that the District has 
provided ample evidence to demonstrate that NOX reductions 
will be more effective at reducing ozone concentrations in Coachella 
Valley, and that the photochemical grid modeling conducted for the 
attainment demonstration, in combination with the supporting analysis 
accompanying the control strategy and other demonstrations, is 
sufficient to support the District's use of NOX 
substitution.
    Comment #3: ALFA faults the EPA's NOX Substitution 
Guidance, contending that it recommends a procedure that fails to 
demonstrate any equivalence between VOC and NOX reductions, 
as required by CAA Section 182(c)(2)(C); relies on incorrect policy 
assumptions; and gives legal justifications that are without merit.
    Response to Comment #3: Comments relating solely to the 
NOX Substitution Guidance are outside the scope of this 
rulemaking action. Our proposed approval of the Plan's use of 
NOX substitution is consistent with the recommended approach 
outlined in the NOX Substitution Guidance, which, while non-
binding and not having the force of regulation, provides a recommended 
procedure for substituting NOX emissions reductions for VOC 
reductions on a percentage basis, consistent with a state's ozone 
attainment plan, control strategy, modeled attainment demonstration, 
and RFP milestones and requirements. As noted in our response to 
Comment #2 above, our approval of the District's use of NOX 
substitution is supported by local conditions and needs as documented 
in the modeling and analysis included in the Coachella Valley Ozone 
Plan and the 2016 AQMP's use of NOx substitution in this RFP 
demonstration is consistent with the requirements of CAA 182(c)(2)(C) 
for the reasons described in this notice.

III. The EPA's Action

    Pursuant to section 110(k)(3) of the CAA, and for the reasons 
provided in our April 16, 2024 proposed rule and this final action and 
response to comments, the EPA is taking final action to approve into 
the California SIP the RFP demonstration of the ``Final Coachella 
Valley Extreme Area Plan for the 1997 8-Hour Ozone Standard,'' dated 
December 2020, as meeting the requirements of CAA sections 172(c)(2) 
and 182(c)(2)(B), and 40 CFR 51.1105(a)(1) and 51.1100(o)(4).
    In addition, the EPA is taking final action to approve CARB's 
``2020 Coachella Valley Vehicle Miles Traveled Emissions Offset 
Demonstration,'' release date January 22, 2021, as meeting the 
requirements of CAA

[[Page 6827]]

section 182(d)(1)(A) and 40 CFR 51.1105(a)(1) and 51.1100(o)(10).

IV. Statutory and Executive Order Reviews

    Under the Clean Air Act, the Administrator is required to approve a 
SIP submission that complies with the provisions of the Act and 
applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). 
Thus, in reviewing SIP submissions, the EPA's role is to approve State 
choices, provided that they meet the criteria of the Clean Air Act. 
Accordingly, this action merely approves State law as meeting Federal 
requirements and does not impose additional requirements beyond those 
imposed by State law. For that reason, this action:
     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Orders 
12866 (58 FR 51735, October 4, 1993) and 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 applications 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, 
February. 16, 1994) directs Federal agencies to identify and address 
``disproportionately high and adverse human health or environmental 
effects'' of their actions on communities with environmental justice 
(EJ) concerns to the greatest extent practicable and permitted by law. 
Executive Order 14096 (Revitalizing Our Nation's Commitment to 
Environmental Justice for All, 88 FR 25251, April 26, 2023) builds on 
and supplements Executive Order 12898 and defines EJ as, among other 
things, ``the just treatment and meaningful involvement of all people, 
regardless of income, race, color, national origin, Tribal affiliation, 
or disability, in agency decision-making and other Federal activities 
that affect human health and the environment.''
    The State did not evaluate EJ considerations as part of its SIP 
submittal; the CAA and applicable implementing regulations neither 
prohibit nor require such an evaluation. Our June 12, 2024 final action 
on other elements of the Plan includes additional discussion about how 
SCAQMD responded to comments related to EJ concerns during development 
of the Plan.\32\ The EPA did not perform an EJ analysis and did not 
consider EJ in this 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. Consideration of EJ is not 
required as part of this action, and there is no information in the 
record inconsistent with the stated goal of Executive Orders 12898 and 
14096 of achieving EJ for communities with EJ concerns.
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    \32\ 89 FR 49815, 49816.
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    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 March 24, 2025. Filing a 
petition for reconsideration by the Administrator of this final rule 
does not affect the finality of this action for the purposes of 
judicial review nor does it extend the time within which a petition for 
judicial review may be filed and shall not postpone the effectiveness 
of such rule or action. This action may not be challenged later in 
proceedings to enforce its requirements. (See section 307(b)(2)).

List of Subjects in 40 CFR Part 52

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

    Dated: January 8, 2025.
Martha Guzman Aceves,
Regional Administrator, Region IX.

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

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

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

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

Subpart F--California

0
2. Section 52.220 is amended by adding paragraphs (c)(614)(ii)(A)(2) 
and (c)(624) to read as follows:

Sec.  52.220  Identification of plan--in part.

* * * * *
    (c) * * *
    (614) * * *
    (ii) * * *
    (A) * * *
    (2) ``South Coast Air Quality Management District, Final Coachella 
Valley Extreme Area Plan for the 1997 8-Hour Ozone Standard,'' dated 
December 2020, the section titled ``Reasonable Further Progress,'' 
pages 6-1 through 6-7.
* * * * *
    (624) The following plan was submitted electronically on March 18, 
2021, by the Governor's designee as an attachment to a letter dated 
March 15, 2021.
    (i) [Reserved]
    (ii) Additional materials.
    (A) California Air Resources Board.
    (1) California Air Resources Board, Staff Report, ``2020 Coachella 
Valley Vehicle Miles Traveled Emissions Offset Demonstration,'' Release 
Date: January 22, 2021.
    (2) [Reserved]
    (B) [Reserved]

[FR Doc. 2025-01110 Filed 1-17-25; 8:45 am]
BILLING CODE 6560-50-P
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