[Federal Register Volume 89, Number 127 (Tuesday, July 2, 2024)]
[Proposed Rules]
[Pages 54748-54753]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-14336]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R09-OAR-2024-0197; FRL-11981-01-R9]


Air Plan Revisions; California; Sacramento Metropolitan Air 
Quality Management District; Reasonably Available Control Technology 
District

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
approve state implementation plan (SIP) revisions from the Sacramento 
Metropolitan Air Quality Management District (SMAQMD or ``District'') 
to address Clean Air Act (CAA or ``Act'') requirements related to the 
2008 8-hour ozone national ambient air quality standards (NAAQS or 
``standards''). These revisions concern emissions of oxides of nitrogen 
(NOX) from boilers, gas turbines, and miscellaneous (misc) combustion 
units and reasonably available control technology (RACT) requirements 
for major sources of NOX in the portion of the Sacramento Metro, CA, 
nonattainment area that is subject to SMAQMD jurisdiction. We are 
taking comments on this proposal and plan to follow with a final 
action.

DATES: Comments must be received on or before August 1, 2024.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R09-
OAR-2024-0197 at https://www.regulations.gov. For comments submitted at 
Regulations.gov, follow the online instructions for submitting 
comments. Once submitted, comments cannot be edited or removed from 
Regulations.gov. The EPA may publish any comment received to its public 
docket. Do not submit electronically any information you consider to be 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Multimedia submissions (audio, 
video, etc.) must be accompanied by a written comment. The written 
comment is considered the official comment and should include 
discussion of all points you wish to make. The EPA will generally not

[[Page 54749]]

consider comments or comment contents located outside of the primary 
submission (i.e., on the web, cloud, or other file sharing system). For 
additional submission methods, please contact the person identified in 
the FOR FURTHER INFORMATION CONTACT section. For the full EPA public 
comment policy, information about CBI or multimedia submissions, and 
general guidance on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets. 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: Eugene Chen, EPA Region IX, 75 
Hawthorne Street (AIR-3-3), San Francisco, CA 94105. By phone: (415) 
947-4304 or by email at [email protected].

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

Table of Contents

I. The State's Submittal
    A. What documents did the State submit?
    B. Are there other versions of the submitted documents?
    C. What is the purpose of the submitted documents?
II. The EPA's Evaluation and Proposed Action
    A. How is the EPA evaluating the submitted documents?
    B. Do the submitted documents meet the evaluation criteria?
    1. Boilers
    2. Gas Turbines
    3. Miscellaneous Combustion Units
    C. Public Comment and Proposed Action
III. Incorporation by Reference
IV. Statutory and Executive Order Reviews

I. The State's Submittal

A. What documents did the State submit?

    Table 1 lists the documents addressed by this proposal with the 
dates that they were adopted by the local air agency and submitted by 
the California Air Resources Board (CARB).

                                          Table 1--Submitted Documents
----------------------------------------------------------------------------------------------------------------
                                 Document/rule
         Local agency                 No.                Document title               Adopted        Submitted
----------------------------------------------------------------------------------------------------------------
SMAQMD........................  ..............  Reasonably Available Control          03/28/2024      04/11/2024
                                                 Technology (RACT) Permits for
                                                 Major Stationary Sources of
                                                 Nitrogen Oxides.
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    On March 28, 2024, SMAQMD adopted portions of several permits 
issued under the District's SIP-approved New Source Review (NSR) permit 
program for submittal into the SIP. These permits contain requirements 
that regulate emissions of NOX, and the District adopted 
these permits for SIP submission to ensure that its major sources of 
NOX are subject to federally enforceable RACT requirements. 
A list of the permits (``District Permits'') contained in this SIP 
revision is included in Table 2 below. On April 11, 2024, CARB 
submitted this SIP revision to the EPA for approval as a revision to 
the California SIP. The EPA has reviewed this submittal and finds that 
it fulfills the completeness criteria of appendix V.\1\
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    \1\ See Docket Item A-14, 40 CFR Appendix V to Part 51--Criteria 
for Determining the Completeness of Plan Submissions.

                         Table 2--District Permits Included in April 11, 2024 Submittal
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                                                                     Unit size
          Source name             Permit No.      Unit name/ID      (MMBtu/hr)               Unit type
----------------------------------------------------------------------------------------------------------------
Mitsubishi Chemical Carbon               24611  Oxidation Oven 1               2  Misc Combustion Unit.
 Fiber and Composites.                   25925  Oxidation Oven 2               2  Misc Combustion Unit.
                                         24613  Oxidation Oven 3               2  Misc Combustion Unit.
                                         24614  Oxidation Oven 4               2  Misc Combustion Unit.
                                         25397  Oxidation Oven--               3  Misc Combustion Unit.
                                                 Line 31.
                                         25398  Oxidation Oven--               3  Misc Combustion Unit.
                                                 Line 31.
                                         25399  Cleaver Brooks                 6  Boiler.
                                                 Boiler.
UC Davis Medical Center.......           17549  Combined Cycle               260  Gas Turbine.
                                                 Turbine.
                                         20216  Boiler 1........              32  Boiler.
                                         20217  Boiler 2........              32  Boiler.
                                         20218  Boiler 3........              32  Boiler.
                                         20219  Boiler 4........              32  Boiler.
Sacramento Metropolitan                  27410  Babcock & Wilcox             109  Boiler.
 Utility District (SMUD)                 27141   Boiler.                     583  Gas Turbine.
 Procter & Gamble Power Plant.           27142  Gas Turbine 1A..             583  Gas Turbine.
                                         27143  Gas Turbine 1B..             500  Gas Turbine.
                                         27144  Gas Turbine 1C..             109  Boiler.
                                                Boiler 1B.......
SMUD Cosumnes Power Plant.....           25801  Turbine 2.......           2,200  Gas Turbine.
                                         25800  Turbine 3.......           2,200  Gas Turbine.
SMUD Campbell Power Plant.....           27118  Gas Turbine.....           1,410  Gas Turbine.
SMUD Carson Power Plant.......           27151  Turbine 27151...             600  Gas Turbine.
                                         27154  Cleaver Brooks               100  Boiler.
                                                 Boiler.
                                         27156  Turbine 27156...             450  Gas Turbine.
----------------------------------------------------------------------------------------------------------------


[[Page 54750]]

B. Are there other versions of the submitted documents?

    We have not previously approved district permits into the SIP for 
any of the sources listed in Table 2. The District Permits were 
submitted to address our June 30, 2023 action that finalized a partial 
approval and partial disapproval of the District's ``Demonstration of 
Reasonably Available Control Technology for the 2008 Ozone NAAQS'' 
(``2017 RACT SIP''). The District's 2017 RACT SIP was submitted to 
demonstrate that its stationary sources are subject to RACT rules for 
the 2008 8-hour ozone NAAQS.\2\ Our partial disapproval related solely 
to the RACT element for major sources of NOX that relied 
upon three district rules: Rule 411 (NOX from Boilers, 
Process Heaters and Steam Generators), Rule 413 (Stationary Gas 
Turbines), and Rule 419 (NOX from Miscellaneous Combustion 
Units). Rules 411 and 413 have previously been approved into the SIP, 
but Rule 419 was locally adopted and submitted to the EPA as part of 
the 2017 RACT SIP development process and has not been approved into 
the SIP. As part of our June 30, 2023 final action, we identified 
deficiencies with the submitted version of Rule 419 but did not act to 
approve or disapprove that rule. As discussed in greater detail below, 
the District elected to submit source-specific permits, rather than 
submitting rule revisions, to address the deficiencies we identified in 
our June 30, 2023 final action.
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    \2\ 88 FR 42248.
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C. What is the purpose of the submitted documents?

    Emissions of NOX contribute to the production of ground-
level ozone, smog and particulate matter (PM), which harm human health 
and the environment. Section 110(a) of the CAA requires states to 
submit plans that provide for implementation, maintenance, and 
enforcement of the NAAQS. In addition, CAA sections 182(b)(2) and (f) 
require that SIPs for ozone nonattainment areas classified as 
``Moderate'' or higher implement RACT for any category of sources 
covered by a control techniques guidelines (CTG) document and for any 
major stationary source of volatile organic compounds (VOCs) or 
NOX. The SMAQMD regulates the Sacramento County portion of 
the Sacramento Metro, CA, ozone nonattainment area that is classified 
as ``Severe'' nonattainment for the 2008 ozone NAAQS.\3\ Therefore, the 
SMAQMD must, at a minimum, ensure that all categories of sources 
covered by a CTG document and all major stationary sources of VOCs or 
NOX within the District implement RACT-level controls. In a 
Severe ozone nonattainment area, any stationary source that emits or 
has the potential to emit at least 25 tons per year (tpy) of VOCs or 
NOX is considered a major stationary source.
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    \3\ 40 CFR 81.305.
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    The SMAQMD relies upon several district rules to implement RACT for 
major sources of NOX, including Rule 411 (NOX 
from Boilers, Process Heaters and Steam Generators), Rule 413 
(Stationary Gas Turbines), and Rule 419 (NOX from 
Miscellaneous Combustion Units). As we explained in our June 30, 2023 
final action on the 2017 RACT SIP, Rule 413 contains a provision that 
explicitly exempts affected units from complying with emission 
limitations during periods of startup and shutdown and does not provide 
for an alternative emission limitation during such periods. Rules 411 
and 419 contain monitoring provisions that preclude the use of 
specified data for determining compliance with emission limitations 
during periods of startup and shutdown. These provisions are 
inconsistent with the EPA's Startup, Shutdown, and Malfunction (SSM) 
Policy as established in the EPA's 2015 SSM SIP Action.\4\ The 
deficiencies with these three rules were the basis for our disapproval 
of the major source NOX element of the 2017 RACT SIP.
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    \4\ ``State Implementation Plans: Response to Petition for 
Rulemaking; Restatement and Update of EPA's SSM Policy Applicable to 
SIPs; Findings of Substantial Inadequacy; and SIP Calls To Amend 
Provisions Applying to Excess Emissions During Periods of Startup, 
Shutdown and Malfunction,'' 80 FR 33840 (June 12, 2015).
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    In Environ. Comm. Fl. Elec. Power v. EPA, 94 F.4th 77 (D.C. Cir. 
2024), the D.C. Circuit held that the EPA impermissibly issued a SIP 
call, under CAA section 110(k)(5), in its 2015 SSM SIP Action \5\ for 
certain SIP provisions applicable to emissions during SSM events, 
including certain automatic exemption type provisions that the EPA had 
previously approved.\6\ While the D.C. Circuit vacated certain SIP 
calls in EPA's 2015 SSM SIP Action, that vacatur was premised on the 
view that the Agency did not make a predicate determination that the 
specific provisions at issue were emissions limitations or that it was 
``necessary or appropriate'' under CAA 110(a)(2)(A) that the SIP 
provisions must be emission limitations. EPA continues to interpret its 
longstanding interpretation that, pursuant to CAA section 302(k), 
emission limitations must be continuous and apply at all times, 
consistent with the decision in Environ. Comm. Fl. Elec. Power v. EPA. 
The Court did not vacate EPA's longstanding guidance for developing 
alternative emission limitations (AELs), should a state or air 
jurisdiction choose to develop and submit AELs into their SIP as a 
means to ensuring they are meeting the applicable CAA requirement that 
emission limitations must be continuous.\7\ States and/or air 
jurisdictions are not precluded from submitting a SIP revision that 
establishes AELs, as SMAQMD did so here.
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    \5\ See 80 FR 33840.
    \6\ See Environ. Comm. Fl. Elec. Power v. EPA, 94 F.4th 77 (D.C. 
Cir. 2024).
    \7\ See 80 FR 33912-33914 and State Implementation Plans: Policy 
Regarding Excess Emissions During Malfunction, Startup, and Shutdown 
(1999 SSM Guidance).
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    Following our June 30, 2023 final action disapproving the major 
source NOX RACT element, SMAQMD examined the permits issued 
under the District's SIP-approved NSR permit program for each of the 
NOX major sources that rely upon Rule 411, 413, or 419 for 
RACT. The District identified conditions in each district permit that 
established NOX emission limits that apply at all times. 
SMAQMD also identified monitoring, recordkeeping, and reporting 
conditions from each district permit to determine compliance with the 
rule and permit requirements. These District Permits are intended to 
remedy the SSM deficiencies, in combination with Rule 411 and Rule 413 
requirements, and are intended to implement RACT for major sources of 
NOX in the District. Our technical support document (TSD) 
has more detailed information about these District Permits.
    In addition, we note that the locally-adopted NSR permits that 
served as the basis of the submitted District Permits contain emission 
limits and other requirements unrelated to NOX RACT that the 
District is not seeking to approve into the SIP. As a result, the 
District has redacted those portions of the submitted permits, such as 
conditions related to carbon monoxide (CO), particulate matter (PM), 
state toxics, and other requirements that are not necessary for 
implementing NOX RACT.

II. The EPA's Evaluation and Proposed Action

A. How is the EPA evaluating the submitted documents?

    Rules in the SIP must be enforceable (see CAA section 110(a)(2)) 
and must not interfere with applicable requirements concerning 
attainment and

[[Page 54751]]

reasonable further progress or other CAA requirements (see CAA section 
110(l)). Generally, SIP rules must require the implementation of RACT 
for each category of sources covered by a CTG, as well as each major 
source of NOX or VOC in ozone nonattainment areas classified 
as Moderate or higher (see CAA section 182(b)(2)). The SMAQMD regulates 
a portion of an ozone nonattainment area classified as Severe for the 
2008 ozone NAAQS and is therefore responsible for ensuring that the 
applicable sources implement RACT-level controls for that ozone 
standard. The District Permits were submitted to be incorporated into 
the SIP to implement RACT-level controls and to fulfill the 
requirements associated with the major source NOX element 
for the 2008 ozone NAAQS.
    Guidance and policy documents that we used to evaluate 
enforceability, revision/relaxation, and stringency requirements for 
the applicable criteria pollutants include the following:
    1. ``State Implementation Plans; General Preamble for the 
Implementation of Title I of the Clean Air Act Amendments of 1990,'' 57 
FR 13498 (April 16, 1992); 57 FR 18070 (April 28, 1992).
    2. ``Issues Relating to VOC Regulation Cutpoints, Deficiencies, and 
Deviations,'' EPA, May 25, 1988 (the Bluebook, revised January 11, 
1990).
    3. ``Guidance Document for Correcting Common VOC & Other Rule 
Deficiencies,'' EPA Region 9, August 21, 2001 (the Little Bluebook).
    4. State Implementation Plans: Response to Petition for Rulemaking; 
Restatement and Update of EPA's SSM Policy Applicable to SIPs; Findings 
of Substantial Inadequacy; and SIP Calls to Amend Provisions Applying 
to Excess Emissions During Periods of Startup, Shutdown and 
Malfunction,'' 80 FR 33839, June 12, 2015.
    5. ``Guidance Memorandum: Withdrawal of the October 9, 2020, 
Memorandum Addressing Startup, Shutdown, and Malfunctions in State 
Implementation Plans and Implementation of the Prior Policy,'' 
September 30, 2021.

B. Do the submitted documents meet the evaluation criteria?

    We have grouped our evaluation of the submitted documents into 
three categories corresponding to the three types of units that 
comprise the major NOX sources listed in Table 2.
1. Boilers
    The SMAQMD is relying upon requirements contained in the current 
SIP-approved version of Rule 411 and in the submitted District Permits 
to implement RACT for the boilers listed in Table 2. In our June 30, 
2023 final action on the 2017 RACT SIP, we evaluated the stringency of 
applicable Rule 411 NOX limits, which vary from 9 parts per 
million (ppm) to 15 ppm, and do not apply during periods of startup and 
shutdown.\8\ We determined that the emission limits in SIP-approved 
Rule 411 achieve RACT-level stringency, but we disapproved based on the 
Agency's SSM policy. We have not identified any information since our 
June 30, 2023 final action to alter our evaluation that the stringency 
of the NOX emission limits are RACT.
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    \8\ 88 FR 42248. See TSD for that action, which is also included 
in the docket for this rulemaking.
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    The District Permits contain source-specific pound per day (lb/day) 
NOX limits for each boiler listed in Table 2. These lb/day 
mass emission limits are continuous and apply at all times. They were 
developed by converting the allowable short-term pound per hour (lb/hr) 
emission limit applicable during normal operations for each source to a 
24-hr average basis. The allowable lb/hr emission limit for each source 
was established pursuant to the control technology determinations made 
via the NSR permitting process and is based upon a concentration limit 
that varies by district permit between 5 to 9 ppm.\9\ Submitting these 
lb/day limits into the SIP will ensure that mass emissions during 
startup and shutdown do not exceed the mass emissions allowed during 
periods of normal operation on a 24-hour average basis. As discussed 
above, we consider the Rule 411 NOX limits to achieve RACT-
level stringency, and these lb/hr District Permit limits achieve or 
exceed this same level of stringency on a mass basis, and they are 
applicable at all times. As a result, when combined with Rule 411 
limits, these District permit limits will ensure that the affected 
units are subject to limits with RACT-level stringency at all times. In 
addition, we determined that the emission limits contained in these 
District Permits are consistent with the criteria recommended in the 
EPA's SSM Policy as appropriate considerations for developing emission 
limitations in the SIP provisions applicable during startup and 
shutdown. Additional information regarding our evaluation of District 
Permit limits, including their consistency with SSM policy criteria, is 
included in our TSD for this action. Based on the existing SIP-approved 
NOX limits in Rule 411, combined with the NOX 
limits that apply at all times contained in the submitted District 
Permits, we propose to determine that the District has established 
requirements in the SIP that are consistent with the EPA's SSM policy 
and implement RACT for the boilers listed in Table 2.
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    \9\ In no case is any source's short term lb/hr emission limit 
based on a concentration higher than 9 ppm, which is also the most 
stringent NOX emission standard established in Rule 411.
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2. Gas Turbines
    For the gas turbines listed in Table 2, the SMAQMD is relying upon 
requirements contained in the current SIP-approved version of Rule 413 
and in the submitted District Permits to implement RACT. In our June 
30, 2023 final action on the 2017 RACT SIP, we evaluated the stringency 
of the 9 ppm NOX limit established by the SIP-approved 
version of Rule 413.\10\ We determined that the emission limit in SIP-
approved Rule 413 achieves RACT-level stringency but disapproved based 
on the Agency's SSM policy because the emission limits in the rule do 
not apply during periods of startup and shutdown. We have not 
identified any information since our June 30, 2023 final action to 
alter our evaluation that the stringency of the NOX emission 
limits comprise RACT.
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    \10\ 88 FR 42252. See also TSD for that action, which is 
available in the docket for this rulemaking.
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    The District Permits contain source-specific lb/day NOX 
limits for each gas turbine listed in Table 2. These lb/day mass 
emission limits are continuous and apply at all times. The source-
specific lb/day NOX limits for the gas turbines were 
developed by examining the maximum number of hours of each mode of 
operation is allowed in a single day, the maximum lb/hr emission rate 
for each mode of operation (either startup or normal operation), and 
summing the 24 hourly mass emission values corresponding to each hour's 
mode of operation to develop a total lb/day emission limit. The maximum 
lb/hr emission limit during normal operations for each source was 
established pursuant to the control technology determinations made via 
the NSR permitting process and is based on a concentration limit that 
varies by district permit between 2.5 to 5 ppm.\11\ As a result, the 
lb/day limits in each source's district permit, which apply at all 
times, will constrain mass emissions of NOX to a level 
consistent with maximum permitted frequency and duration of shutdown 
events and also to a level of normal operations that is more stringent 
than Rule 413 concentration

[[Page 54752]]

limits. In other words, we consider the Rule 413 NOX limits 
to achieve RACT-level stringency because these District Permit limits 
achieve or exceed the most stringent level of control in these limits 
on a mass basis and they are applicable at all times. Thus, when 
combined with Rule 413 emission limits, the District permit limits will 
ensure that the affected units are subject to RACT-level stringency at 
all times. We have determined that the lb/day emission limits contained 
in these District Permits are consistent with the criteria recommended 
in the EPA's SSM Policy as appropriate considerations for developing 
emission limitations in SIP provisions applicable during startup and 
shutdown. Further details regarding our evaluation of District Permit 
limits, including their consistency with SSM policy criteria, are 
included in our TSD for this action.
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    \11\ In all cases, each source's short term lb/hr emission limit 
during normal operations is based on a concentration limit that is 
more stringent than 9 ppm, which is the most stringent 
NOX emission standard established in Rule 413.
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    Based on the existing SIP-approved NOX limits in Rule 
413, combined with the NOX limits that apply at all times 
contained in the submitted District Permits, we propose to determine 
that the District has established requirements in the SIP that are 
consistent with the EPA's SSM policy and implement RACT for the gas 
turbines listed in Table 2.
3. Miscellaneous Combustion Units
    Unlike for boilers and gas turbines, the SMAQMD is not relying upon 
Rule 419 requirements to implement RACT for the miscellaneous 
combustion units (carbon fiber oxidation ovens) listed in Table 2. 
Instead, it is only relying upon the requirements contained in the 
submitted District Permits. As discussed in our June 30, 2023 final 
action on the 2017 RACT SIP, the ovens listed in Table 2 are subject to 
Rule 419, which was submitted to the EPA for incorporation into the SIP 
on January 31, 2019. We have not yet proposed action on Rule 419, and 
no version of it has been previously approved into the SIP.
    The District Permits establish NOX concentration limits 
of 30 ppm for each oven. These limits are continuous and apply at all 
times. The EPA has not published a CTG document or Alternative Control 
Techniques (ACT) document that is relevant for the control of 
NOX emissions for units such as the carbon fiber oxidation 
ovens. As a result, we have evaluated the District Permit limits 
through comparison with NOX limits established in 
miscellaneous combustion unit rules from other California air 
districts. We have summarized these values in Table 3 below.

                                Table 3--Comparison of Miscellaneous Combustion Unit Emission Limits (Gaseous Fuel Only)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                        San Joaquin
                                                      Valley unified
                                        Sacramento      (SJVU)  air
                                        metro AQMD       pollution                                 Imperial county APCD rule   Ventura county APCD rule
         Equipment category              district         control     South coast AQMD rule 1147             400.4                       74.34
                                          permits        district
                                                        (APCD) rule
                                                           4309
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   NOX emission limit in parts per mission by volume (ppmv)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Asphalt Manufacturing...............  ..............              40  40........................  ..........................  40.
Incinerator/Crematory...............  ..............  ..............  60........................
Metal Heat Treating/Metal Melting     ..............  ..............  60........................  ..........................  60.
 Furnace.
Oven, Dehydrator, Dryer, Heater, or               30  ..............  30 or 60 \a\..............  30 \c\....................  80.
 Kiln.
Other Miscellaneous combustion unit.  ..............              40  30........................  ..........................  30 or 60.\a\
All miscellaneous combustion units    ..............          40-110  40 or 60.\a\
 when liquid fuel-fired.
Cooking Unit........................  ..............  ..............  ..........................  40 or 60.\b\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ 60 ppm if process temperature >=1,200 deg F.
\b\ 60 ppm if process temperature >=500 deg F.
\c\ Imperial County APCD Rule 400.4 applies to wallboard kilns only.

    As seen in Table 3 above, the 30 ppm limit established in the 
District Permits is equal to or exceeds the NOX emission 
limit established for ovens in other examined ozone nonattainment 
areas. In particular, the limit established in the District Permits 
could be considered the most stringent limit among all of those 
evaluated, since it does not provide a separate limit when a unit is 
operating above specific process temperatures.
    The District Permits also contain source-specific lb/day 
NOX limits for each oven. These lb/day mass emission limits 
are continuous and apply at all times. They were developed by 
converting the allowable short-term lb/hr emission limit applicable 
during normal operations for each source to a 24-hr average basis. The 
allowable lb/hr emission limit for each source was established pursuant 
to the control technology determinations made via the NSR permitting 
process and corresponds to the 30 ppm NOX concentration 
limit. Submitting these lb/day limits into the SIP will provide an 
additional constraint to ensure that mass emissions during startup and 
shutdown do not exceed the mass emissions allowed during periods of 
normal operation on a 24-hour average basis. As a result, we propose to 
determine that the District has established requirements in the SIP 
that implement RACT for the miscellaneous combustion units listed in 
Table 2.
    Finally, for each of the boilers, gas turbines, and miscellaneous 
combustion units listed in Table 2, we are proposing to determine that 
our approval of the District Permits for each of the sources would 
comply with CAA section 110(l), because the proposed SIP revision would 
strengthen the SIP by adding new requirements and would not interfere 
with any applicable CAA requirements, including requirements for RFP 
and attainment of the NAAQS. CAA section 193 does not apply to this 
action because the District Permit conditions have not previously been 
approved into the SIP and were therefore not in effect before November 
15, 1990.

C. Public Comment and Proposed Action

    As authorized in section 110(k)(3) of the Act, the EPA proposes to 
approve the District Permits, as adopted on March 28, 2024, into the 
California SIP. Based on our discussion in Section II.B of this 
document, we propose to determine that the District Permits will comply 
with the EPA's SSM policy and other applicable CAA requirements and 
will, in conjunction with the SIP-approved NOX limits 
already established in Rule 411 and 413,

[[Page 54753]]

implement RACT for each major NOX source in the District.
    In addition, as discussed in our June 30, 2023 final action, the 
absence of emission limits that apply at all times was the basis for 
our disapproval of the major source NOX element of the 2017 
RACT SIP. Since we are proposing to determine that the District 
Permits, in conjunction with the SIP-approved NOX limits 
already established in Rule 411 and 413, implement RACT for each major 
NOX source in the District, we are also proposing to approve 
the major source NOX element of the District's 2017 RACT 
SIP.
    We will accept comments from the public on this proposal until 
August 1, 2024. If we take final action to approve the District Permits 
as proposed, our final action will incorporate these District Permits 
into the federally enforceable SIP. In addition, it will permanently 
stop the sanctions and Federal implementation plan (FIP) clocks started 
by our June 30, 2023 final action, and it will address the EPA's 
obligation to promulgate a FIP arising from our February 3, 2017 
finding of failure to submit.\12\
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    \12\ 82 FR 9158. The sanctions clock triggered by this finding 
of failure to submit was permanently stopped by a finding of 
completeness made by the EPA on August 23, 2018 for the District's 
2017 RACT SIP submittal.
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III. Incorporation by Reference

    In this rule, the EPA is proposing to include in a final EPA rule 
regulatory text that includes incorporation by reference. In accordance 
with requirements of 1 CFR 51.5, the EPA is proposing to incorporate by 
reference the District Permits listed in Table 2, as adopted on March 
28, 2024, which regulate NOX emissions from boilers, gas 
turbines, and miscellaneous combustion units. The EPA has made, and 
will continue to make, these materials available through https://www.regulations.gov and at the EPA Region IX Office (please contact the 
person identified in the FOR FURTHER INFORMATION CONTACT section of 
this preamble for more information).

IV. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submission that complies with the provision of the Act and applicable 
federal regulations. 42 U.S.C. 740(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 proposed action merely proposes to approve state law 
as meeting federal requirements and does not impose additional 
requirements beyond those imposed by state law. For that reason, this 
proposed 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 proposes to approve 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 CAA.
    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 EJ considerations as part of its SIP 
submittal; the CAA and applicable implementing regulations neither 
prohibit nor require such an evaluation. The EPA did not perform an EJ 
analysis and did not consider EJ in this action. 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 E.O. 12898 of achieving EJ 
for people of color, low-income populations, and Indigenous peoples.

List of Subjects in 40 CFR Part 52

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

    Dated: June 25, 2024.
Martha Guzman Aceves,
Regional Administrator, Region IX.
[FR Doc. 2024-14336 Filed 7-1-24; 8:45 am]
BILLING CODE 6560-50-P