[Federal Register Volume 89, Number 63 (Monday, April 1, 2024)]
[Proposed Rules]
[Pages 22363-22371]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-06807]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R10-OAR-2023-0438, FRL-11366-01-R10]


Air Plan Approval; OR; Permitting Rule Revisions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) proposes to approve 
revisions to the Oregon State Implementation Plan (SIP) submitted on 
March 27, 2023. The submitted changes are designed to strengthen the 
stationary source permitting rules by eliminating generic plant site 
emission limits in favor of source-specific and source-category 
specific limits, updating construction notification requirements, 
clarifying the use of modeling and monitoring for compliance assurance, 
and streamlining the application process.

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

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R10-
OAR-2023-0438, at https://www.regulations.gov. Follow the online 
instructions for submitting comments. Once submitted, comments cannot 
be edited or removed from https://www.regulations.gov. The EPA may 
publish any comment received to its public docket. Do not 
electronically submit any information you consider to be Confidential 
Business Information (CBI) or other information the disclosure of which 
is restricted by statute. Multimedia submissions (audio, video, etc.) 
must be accompanied by a written comment. The written comment is 
considered the official comment and should include discussion of all 
points you wish to make. The EPA will generally not consider comments 
or comment contents located outside of the primary submission (i.e., on 
the web, cloud, or other file sharing system). For

[[Page 22364]]

additional submission methods, the full EPA public comment policy, 
information about CBI or multimedia submissions, and general guidance 
on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: Kristin Hall, EPA Region 10, 1200 
Sixth Avenue, Suite 155, Seattle, WA 98101, at (206) 553-6357 or 
[email protected].

SUPPLEMENTARY INFORMATION: Throughout this document, wherever ``we'' or 
``our'' is used, it means the EPA.

Table of Contents

I. Background
    A. State Implementation Plan
    B. State Submission
II. Evaluation
    A. Division 200--General Air Pollution Procedures and 
Definitions
    B. Division 208--Visible Emissions and Nuisance Requirements
    C. Division 209--Public Participation
    D. Division 210--Stationary Source Notification Requirements
    E. Division 216--Air Contaminant Discharge Permits
    F. Division 222--Stationary Source Plant Site Emission Limits
    G. Division 224--New Source Review
    H. Division 225--Air Quality Analysis Requirements
    I. Division 226--General Emission Standards
    J. Division 228--Requirements for Fuel Burning Equipment
    K. Division 232--Emission Standards for VOC Point Sources
    L. Division 234--Emission Standards for Wood Products Industries
    M. Division 21--General Emission Standards for Particulate 
Matter
III. Proposed Action
    A. Rule Sections To Be Incorporated by Reference
    B. Rule Sections To Be Removed From Incorporation by Reference
IV. Incorporation by Reference
V. Statutory and Executive Order Reviews

I. Background

A. State Implementation Plan

    The Clean Air Act requires the EPA to establish national ambient 
air quality standards (NAAQS) for carbon monoxide, lead, nitrogen 
dioxide, ozone, particulate matter, and sulfur dioxide.\1\ Each state 
has a State Implementation Plan (SIP) designed to meet the NAAQS 
through various air pollution regulations, control measures and 
strategies. A SIP contains elements such as emission limits, pollution 
control technology requirements, permitting programs, and enforcement 
mechanisms, among other elements. Each state revises its SIP over time 
to respond to new Federal requirements and to address changing air 
quality conditions.
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    \1\ See Clean Air Act section 109.
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    States submit SIP revisions to the EPA for review and approval.\2\ 
The EPA takes action through notice and comment rulemaking to approve 
and incorporate submitted state air quality regulations by reference 
into the SIP, codified in the Code of Federal Regulations (CFR). As 
part of the SIP, state regulations are enforceable by the EPA and by 
citizens in Federal district court.\3\
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    \2\ See Clean Air Act section 110.
    \3\ See Clean Air Act section 304.
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B. State Submission

    On March 27, 2023, the Oregon Department of Environmental Quality 
(DEQ) submitted a SIP revision to the EPA for approval into the Oregon 
SIP, codified at 40 CFR part 52, subpart MM. The submitted changes, 
State effective March 1, 2023, update the stationary source permitting 
programs established in chapter 340 of the Oregon Administrative Rules 
(OAR). The Oregon Department of Environmental Quality (Oregon DEQ) is 
the permitting authority throughout the State, except where Lane 
Regional Air Protection Agency has been authorized to permit sources 
located in Lane County, Oregon.

II. Evaluation

    The following sections of this preamble describe the significant 
changes made to the Oregon air permitting regulations and evaluate the 
changes with respect to Clean Air Act requirements.\4\
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    \4\ We note that we have not described minor wording changes and 
clarifications that do not alter the meaning of the rules. We also 
note that we intend to address the submitted changes to Division 
214, related to stationary source reporting requirements, in a 
separate action.
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A. Division 200--General Air Pollution Procedures and Definitions

    Oregon clarified and updated several centralized definitions which 
are used throughout the Oregon air quality regulations.\5\ The State 
updated the definition of ``air contaminant'' to clearly exclude 
uncombined water.\6\ This update is appropriate because: (1) uncombined 
water is not a criteria pollutant or otherwise regulated air pollutant 
under the Clean Air Act; and (2) uncombined water is not included when 
measuring particulate matter emissions, consistent with the EPA's 
definition at 40 CFR 51.100(pp). Oregon also made clear that the 
definition of ``construction'' includes the replacement of a source and 
that the definition of ``emission limit'' includes a permit condition 
or order. These changes are appropriate because they strengthen and 
clarify the SIP.
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    \5\ See OAR 340-200-0020 General Air Quality Definitions.
    \6\ Uncombined water means droplets of water that have not 
combined with hygroscopic particles or do not contain dissolved 
solids.
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    The State also made minor updates to certain terms; for example, 
Oregon clarified that all fluorinated greenhouse gases, as defined in 
40 CFR part 98, are included in the State's definition of ``greenhouse 
gas.'' Oregon updated the definition of ``major source'' to ensure that 
all uses of the term throughout the air quality rules point to the 
corresponding definition based on the applicable permitting program 
(the Clean Air Act defines the term ``major source'' differently based 
on area designation, type of pollutant, etc.). In addition, the State 
clarified the correct definition of ``particulate matter'' to be used 
in regulating visible emissions. Oregon also updated the definition of 
``significant emission rate'' to point to the EPA test method used to 
measure inorganic fluoride compounds and updated the definition of 
``VOC'' to align with the Federal definition in 40 CFR 51.100(s). We 
propose to approve these clarifying updates.
    Oregon revised the definition of ``significant impact level'' to 
remove the levels established for the coarse particulate matter 
(PM10) annual standard. This change is consistent with the 
EPA's revocation of the PM10 annual standard on October 17, 
2006 (71 FR 61144). Finally, Oregon struck the definition of ``generic 
plant site emission limit'' because the State has repealed the 
permitting regulations in which the term is used. For further 
discussion, please see section II.G. of this preamble. We propose to 
approve the removal of these obsolete terms and definitions.

B. Division 208--Visible Emissions and Nuisance Requirements

    Oregon updated the visible emission regulations in Division 208 in 
several ways. Oregon spelled out that the visible emission limits in 
OAR 340-208-0110 do not apply to recovery furnaces that are subject to 
the separate standards for wood products industries established in 
Division 234. In the same rule section, the State removed text that 
historically served to phase in tighter, 20 percent opacity limits. The 
limits are now widely applicable. In addition, Oregon clarified that, 
in and around the Portland area, industrial fuel burning equipment that 
fires wood residue is limited to no more than 0.10 grains per

[[Page 22365]]

standard cubic foot of exhaust.\7\ We propose to approve the submitted 
changes because they clarify how and where visible emission limits 
apply without relaxing the requirements.
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    \7\ If installed, constructed or last modified after June 1, 
1970. Such equipment installed before that date is limited to 0.20 
grains per standard cubic foot.
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C. Division 209--Public Participation

    In the submission, the State updated the centralized public 
participation requirements in Division 209. Oregon revised OAR 340-209-
0080 to spell out the timeline and actions required for an owner or 
operator to appeal a permit decision, specifically adding text stating 
that an issued permit is effective on the date of signature, unless the 
applicant requests a hearing to contest the permit within 20 days of 
the notification date. In addition, Oregon made clear that a permit 
denial is effective 60 days from the notification date unless the 
applicant requests a hearing within that timeframe. We propose to 
approve the changes because they make the permit appeal process 
transparent to applicants and the public.

D. Division 210--Stationary Source Notification Requirements

    In the submission, Oregon made changes to the registration 
requirements in Division 210. The current SIP requires that any air 
contaminant source that is not otherwise required to obtain an air 
contaminant discharge permit under Division 216, or title V operating 
permit under Division 218, must register with the permitting authority 
upon request. The State updated the general registration provisions in 
OAR 340-210-0100 to make clear to owners and operators of subject 
sources that appropriate record-keeping is required and that failure to 
pay fees may be cause to terminate registration.\8\ We propose to 
approve the submitted changes because they clarify what is required to 
maintain source registration and therefore strengthen the SIP.
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    \8\ Registered sources include sources such as motor vehicle 
surface coating operations, dry cleaners using perchloroethylene, 
and other types of smaller sources. Registering such sources helps 
the Oregon DEQ inventory statewide emissions, provide technical 
assistance, and communicate with owners and operators.
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    In the submission, the State also made changes to the notice of 
construction provisions in Division 210. An owner or operator of a 
proposed new source that will emit any regulated air pollutant, and 
that is not otherwise required to obtain an air contaminant discharge 
permit under Division 216 or a title V permit under Division 218, must 
notify the permitting authority, consistent with Division 210. In 
addition, an owner or operator seeking to modify an existing source 
must notify the permitting authority if the modification would increase 
regulated air pollutant emissions, replace an emissions device, or 
modify or replace an air pollution control device. We note that such a 
modifying source may or may not have an existing air contaminant 
discharge permit or title V permit.
    In the submission, Oregon revised the applicability requirements in 
OAR 340-210-0205 to make clear that owners or operators must notify the 
permitting authority using the appropriate application materials before 
undertaking any of the covered activities in Division 210. We propose 
to approve the changes as strengthening the SIP.
    The State also added language to OAR 340-210-0225 to clarify which 
kinds of changes fall under each notification type prescribed in the 
Division 210 rules (Types 1, 2, 3 and 4), in addition to the associated 
requirements for owners and operators under each type. Type 1 changes 
generally consist of construction and modification for which an owner 
or operator is not required to obtain an air contaminant discharge 
permit or permit modification under Division 216, and where the changes 
would not increase emissions in a significant way, would not increase 
emissions above an existing plant site emission limit (PSEL), and would 
not be used to establish a federally enforceable limit on potential to 
emit.\9\ A construction or modification may also be a Type 1 change if 
it is one of a list of equipment, units, or activities that are 
expected to result in little to no change in emissions.\10\ Type 2 
changes include construction or modification for which the owner or 
operator is not required to obtain an air contaminant discharge permit 
or permit modification under Division 216, and where the construction 
or modification would not cause or increase emissions above certain 
regulatory thresholds, such as the significant emission rate.\11\ Type 
3 changes include construction or modification where the construction 
or modification would cause or increase emissions above certain 
regulatory thresholds, such as the significant emission rate.\12\ 
Finally, Type 4 changes include construction or modification that is 
subject to new source review (NSR) requirements governed by Division 
224. We propose to approve the changes because they are designed to 
ensure that construction activities receive the proper review by the 
permitting authority.
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    \9\ More specifically, the construction or modification would: 
have emissions from any new, modified, or replaced device or 
activity, or any combination of devices or activities, of less than 
or equal to the de minimis levels defined in OAR 340-200-0020; not 
result in an increase of emissions from the source above any PSEL; 
not result in an increase of emissions from the source above the 
netting basis by more than or equal to the SER; not be used to 
establish a federally enforceable limit on the potential to emit; 
and not require a technically achievable control technology 
determination under OAR 340-226-0130 or a maximum achievable control 
technology determination under OAR 340-244-0200.
    \10\ Activities that are expected to result in little or no 
change in emissions include, for example: vacuum pumps; hand-held 
sanding equipment; Lithographic printing equipment which uses laser 
printing; concrete application and installation; among numerous 
other activities. See submitted changes to OAR 340-210-0225 in the 
submission in the docket for this action.
    \11\ Specifically, construction or modification that would have 
emissions from any new, modified, or replaced device or activity, or 
any combination of devices or activities, of less than the 
significant emission rate (SER) defined in OAR 340-200-0020; not 
result in an increase of emissions from the source above any plant 
site emission limit (PSEL); not result in an increase of emissions 
from the source above the netting basis by more than or equal to the 
SER; not be used to establish a federally enforceable limit on the 
potential to emit; be used to establish a State-only enforceable 
limit on the potential to emit; not require a technically achievable 
control technology (TACT) determination under OAR 340-226-0130 or a 
maximum achievable control technology (MACT) determination under OAR 
340-244-0200; and not cause or contribute to a new exceedance of the 
NAAQS for a new or replaced device or activity.
    \12\ Specifically, construction or modification that would 
result in emissions from any new, modified, or replaced device or 
activity, or any combination of devices or activities, of more than 
or equal to the SER defined in OAR 340-200-0020; result in an 
increase of emissions from the source above any PSEL before applying 
unassigned emissions or emissions reduction credits available to the 
source but less than the SER after applying unassigned emissions or 
emissions reduction credits available to the source; be used to 
establish a federally enforceable limit on the potential to emit; 
require a TACT determination under OAR 340-226-0130 or a MACT 
determination under 340-244-0200; or not cause or contribute to a 
new exceedance of a National Ambient Air Quality Standard adopted 
under OAR chapter 340, division 202 for a new or replaced device or 
activity.
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    Oregon also revised the application requirements in OAR 340-210-
0230 to specify what should be in a notice of construction application 
and to require that applicants must generally use the State-provided 
online electronic forms. In addition, applications must include 
information on production, throughput, material usage, and emissions 
with supporting calculations. Any person proposing a Type 2 or Type 3 
change for a new or replaced device or activity must also submit an air 
quality analysis, for any pollutants that are emitted above the de 
minimis emission level, demonstrating that the emissions from the 
individual device or activity, including reductions due to air 
pollution control devices or permitted limits on production capacity, 
will not

[[Page 22366]]

cause or contribute to a new exceedance of the NAAQS. We propose to 
approve these revisions as strengthening the SIP because they require 
an air quality analysis to demonstrate the NAAQS are protected when 
Type 2 and Type 3 construction and modification activities are planned 
at a source.
    The State revised the construction approval conditions in OAR 340-
210-0240 to clarify when and how an applicant may proceed with 
construction or modification. For a Type 1 change, an owner or operator 
may proceed with construction immediately after notifying the 
permitting authority, unless the owner or operator requests 
confirmation. For a Type 2 change, an owner or operator may construct 
or modify 60 calendar days after the permitting authority receives the 
complete notice application and fees, or on the date that the 
permitting authority approves the application in writing, whichever is 
sooner, unless the permitting authority determines that the activity 
does not qualify as a Type 2 change. When planning a Type 3 or Type 4 
change, an owner or operator must obtain the appropriate air 
contaminant discharge permit prior to proceeding with construction or 
modification. Upon approval, an owner or operator must commence 
construction or modification within 18 months. Approval terminates if 
not commenced within 18 months, except that a source may request one 18 
month extension of the deadline. Oregon also spelled out that any 
construction or modification must happen according to the plans and 
specifications reviewed and approved by the permitting authority. 
Finally, Oregon revised OAR 340-210-0250 to clarify which types of 
permits must be obtained for Type 3 and 4 changes. We propose to 
approve the changes because they clarify the construction approval 
requirements and require owners and operators to construct according to 
approved plans.

E. Division 216--Air Contaminant Discharge Permits

    As part of the submission, the State revised the air contaminant 
discharge permit (ACDP) requirements in Division 216 to ensure proper 
permitting and NAAQS compliance. First, Oregon updated the general 
applicability provisions in OAR 340-216-0020 to make clear that the 
owner or operator of a source must construct and operate the permitted 
facility in accordance with previously-approved plans and 
specifications. Second, the State revised OAR 340-216-0025 to add 
clarifying language about the permitting authority's ability to 
reassign a source to a different permit type. Specifically, Oregon 
added language stating that, notwithstanding the other eligibility 
requirements already established in the State regulations for the 
different types of ACDPs, the permitting authority may change the 
specific permit type to be issued to a source based on several 
additional factors including the compliance history of the facility's 
corporate officers, parent company, subsidiaries, and other related 
people and entities. We propose to approve these changes because they 
are designed to enhance State oversight of stationary source 
construction and operation.
Permit Application Procedures
    Oregon made changes to the permit application procedures in OAR 
340-216-0040 to require additional application materials when a source 
applies for a new, renewed, or modified permit. These materials were 
added to help ensure that subject sources will not cause or contribute 
to a new exceedance of the NAAQS, including the short-term NAAQS 
promulgated by the EPA in 2010 for SO2 and NO2.
    When requesting a new ACDP--except a new short-term activity 
permit--in addition to what was already required in the application, 
each source must also provide:
     The make, model, and identification number associated with 
activities and devices used at the source, if available;
     The specific exhaust parameters for devices used at the 
source;
     The most recent information reported to the EPA's toxics 
release inventory (TRI) for that specific source, if that source is 
subject to the TRI program;
     An air quality impact analysis conducted in accordance 
with Division 225 demonstrating that the source's emissions will not 
cause or contribute to a new exceedance of any NAAQS;
     The anticipated date of commencement of construction; and
     The anticipated date of construction completion.
    When requesting to renew an ACDP permit, in addition to the 
already-required materials, each source must also submit:
     All information required for a new ACDP if that 
information has changed since the last permit renewal or issuance;
     A complete list of all devices and activities at the 
source;
     An estimate of the amount and type of each air contaminant 
emitted by the source; and
     All changes to the source since the last permit issuance 
and all requirements applicable to those changes; and
     When required by the permitting authority, an air quality 
analysis conducted in accordance with Division 225 demonstrating that 
the source's emissions will not cause or contribute to a new exceedance 
of a NAAQS.
    For requests to modify an ACDP permit, in addition to the already-
required materials, each source must also submit:
     When required by the permitting authority, an air quality 
analysis conducted in accordance with Division 225 demonstrating that 
the source's emissions will not cause or contribute to a new exceedance 
of a NAAQS.
    For all permit applications, if additional information is needed to 
complete the permit application, the permitting authority will send a 
written request to the applicant and require the information be 
submitted within 60 days. Applicants may request a good cause 
extension. We propose to approve the changes to the permit application 
procedures because they are designed to provide the permitting 
authority with the specific information needed to issue a permit that 
protects ambient air quality, including the short-term NAAQS.
Short-Term Activity Permits
    With respect to short-term activity ACDPs, the State revised OAR 
340-216-0054 to make clear that a short-term permit is only available 
for activities that either do not require a title V operating permit, 
that are unexpected or emergencies, or that involve a pilot plant or 
exploratory emissions unit. The State also added several application 
requirements, including, if required by the permitting authority, an 
air quality impact analysis demonstrating that the source's emissions 
will not cause or contribute to a new exceedance of the NAAQS. The 
State added that a short-term activity permit automatically terminates 
after 60 days. A source may request one 60-day extension, but no more. 
If a short-term activity permit is issued to an already-permitted 
source, that source must include the emissions from the short-term 
activity when determining compliance with applicable plant site 
emission limits. We propose to approve these revisions because they are 
intended to prevent covered activities from causing or contributing to 
a new NAAQS exceedance.
General Permits
    As specified in Division 216, general ACDPs are established by the 
permitting authority for specific source categories when there are 
multiple sources with

[[Page 22367]]

the same, or substantially similar, types of operations. The general 
permit provisions indicate that such a permit is appropriate when all 
requirements applicable to a covered operation may be included in the 
general permit, the emission limitations, monitoring, recordkeeping and 
reporting are the same for all operations covered by the general 
permit, and the regulated pollutants emitted are of the same type for 
all covered operations. Examples include rock crushers and asphalt 
plants. For such general permits, the State added procedures to OAR 
340-216-0060 spelling out how a person may petition to add a new 
category to the list of source categories covered by general permits. 
We propose to approve the revisions to OAR 340-216-0060.
Simple and Standard Permits
    Simple ACDPs, described in OAR 340-216-0064, generally limit a 
source's emissions to less than the significant emission rate (SER) for 
each pollutant. Oregon updated these requirements to ensure that 
emissions from a source permitted under a simple permit will not cause 
or contribute to a new exceedance of a NAAQS. In particular, the 
revisions require that a simple permit include each physical or 
operational limit required to ensure all devices and activities at a 
source are controlled, or a requirement to conduct ambient monitoring 
to ensure compliance with the NAAQS. Oregon also extended the simple 
permit term from 5 years to 10 years. For standard permits in OAR 340-
216-0066, Oregon made similar changes, except that the permit term for 
standard permits will generally remain at 5 years, except when issued 
to meet major new source review (NSR), in which case the permit will 
have no expiration date. We propose to approve these changes as 
consistent with the EPA's NSR regulations at 40 CFR 51.161 through 166. 
For further discussion, see section II.G. of this preamble.
Permit Termination and Department-Initiated Permit Modifications
    Oregon revised the rules addressing termination of permits in OAR 
340-216-0082 to make clear that a source may not operate after an air 
contaminant discharge permit has been terminated. However, when a 
construction approval permit is terminated for failure to commence or 
complete construction within required timeframes, a source may request 
an extension for good cause and a terminated permit may be reinstated 
by the permitting authority if the source submits a complete renewal 
application within 30 days of termination and pays all applicable fees. 
Oregon also revised OAR 340-216-0884 to make clear that department-
initiated modifications are issued by the permitting authority 
following the regulatory procedures for each type of permit, including 
the appropriate public participation process spelled out in Division 
209. We propose to approve the changes because they clarify the public 
process for department-initiated modifications and spell out the permit 
termination procedures.
Permit Fees
    In the submission, Oregon requested to remove a table of permit 
fees from the SIP (Table 2 to OAR 340-216-8020). This table includes 
the specific dollar amounts charged for various types of permit actions 
and is revised over time by the State for inflation and needed revenue 
adjustments. We propose to approve Oregon's request to remove the fee 
table from the SIP because the overall requirement for sources to pay 
pre-construction permit fees at OAR 340-216-8020(1) will remain in the 
SIP, consistent with the requirements of Clean Air Act section 
110(a)(2)(L).\13\
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    \13\ OAR-340-214-0820(a).
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F. Division 222--Stationary Source Plant Site Emission Limits

    Plant site emission limits (PSELs) are included in most Oregon air 
contaminant discharge permits and title V operating permits as a means 
of regulating plantwide increases and decreases in air emissions. 
Historically, PSELs were established by the Oregon DEQ at either 
source-specific levels or standardized ``generic'' levels for each 
pollutant. Generic PSELs were defined in the Oregon air regulations as 
annual limits set at one (1) ton less than the significant emission 
rate (SER) for each pollutant. In practice, a source with capacity less 
than the SER for a pollutant would often be assigned a generic PSEL in 
a permit. However, many such sources had actual emissions lower than 
the generic PSEL. This system was devised in 2001 as a permit 
streamlining practice that allowed owners or operators to increase 
emissions up to the generic PSEL without requiring a permit 
modification, if there were no physical modifications to the source. 
Oregon has since determined that the use of generic PSELs is no longer 
an appropriate permitting tool. In the submission, the State eliminated 
generic PSELs in favor of PSELs specific to an individual source or 
source category. The changes are described in the following paragraphs.
    Oregon clarified in the general requirements for establishing PSELs 
at OAR 340-222-0035 that such limits must include aggregate 
insignificant activities, if applicable, because aggregate 
insignificant activities must be considered when determining new source 
review applicability under Division 224. We propose to approve this 
clarification because it is intended to make sure that sources are 
appropriately brought into the new source review permitting program for 
review.
    The State repealed the generic PSEL option at OAR 340-222-0040 and 
all references to generic PSELs in Division 222. Oregon then revised 
the annual PSEL provisions in OAR 340-222-0041 to account for the 
repeal of the generic PSEL option and to further clarify how the 
permitting authority will establish all types of annual PSELs. 
Specifically, for a general ACDP, the permitting authority may 
establish a general PSEL for a pollutant based on the corresponding 
source category's maximum potential to emit that pollutant.\14\ For 
each source subject to a simple ACDP, a source-specific PSEL is 
established for each regulated pollutant based on the facility's 
potential to emit. In addition, for each source subject to a standard 
ACDP, the permitting authority will establish a source-specific PSEL 
for each regulated pollutant based on the facility's potential to emit, 
netting basis, or a level requested by the applicant, whichever is 
less. This approach is designed to yield permits that more accurately 
reflect actual emissions and to ensure the permitting authority has the 
opportunity to require and review

[[Page 22368]]

air quality modeling for compliance with the short-term NAAQS.
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    \14\ Revised OAR 340-222-0041(1) states ``For sources subject to 
a General ACDP or a General Oregon Title V Operating Permit, a PSEL 
may be set based on the potential to emit of the largest emitting 
source in that source category for all sources on that permit type 
in the State. PSELs will be set for all regulated pollutants emitted 
at more than the de minimis emission level.'' The EPA interprets 
this to mean that the PSEL may be set based on the potential to emit 
of the largest emitting source in the source category for which the 
permitting authority issued the General ACDP. For example, the 
Oregon DEQ has issued a General ACDP for portable and stationary 
rock crushers, screens, and associated material handling activities 
(SIC 1442): Permit Number AQGP-008 (available at https://www.oregon.gov/deq/FilterPermitsDocs/AQGP-008.pdf). Revised OAR 340-
222-0041(1) permits the Oregon DEQ to set the PSELs for sources 
eligible under this General ACDP to the potential to emit of the 
largest emitting portable and stationary rock crusher, screening, 
and material handling source that holds a current General ACDP under 
AQGP-008 in Oregon. The EPA further understands that a source with 
the potential to emit equal to or greater than the significant 
emission rate (SER) for a pollutant is subject to a standard ACDP 
and therefore any PSEL revisions for sources subject to General 
ACDPs will always be lower than prior Generic PSELs.
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    Finally, Oregon clarified that an increase in the PSEL for 
PM10 or PM2.5 is subject to air quality analysis 
requirements but an increase in total particulate matter is not, as 
described in section II.H. of this preamble. In reviewing the repeal of 
generic PSELs and the changes to Division 222, we propose to approve 
the changes described as well as other changes Oregon made to the PSEL 
rules because they clarify and strengthen the SIP.

G. Division 224--New Source Review

    Oregon revised the new source review (NSR) requirements in Division 
224 to remove the expiration dates from NSR permits. The State made 
this change because the permitting authority must reissue an expired 
NSR permit in order to change NSR permit conditions. For certain 
sources subject to both NSR and title V, NSR permits must be 
incorporated into title V operating permits and this change to remove 
expiration dates is intended to eliminate the need for the source to 
reapply for the same permit and for the permitting authority to reissue 
the permit. We propose to approve the removal of NSR permit expiration 
dates because the EPA's NSR regulations at 40 CFR 51.161 through 166 do 
not mandate NSR permits expire after a specific duration and removal of 
the expiration dates does not affect the stringency of the SIP.

H. Division 225--Air Quality Analysis Requirements

    Certain sources seeking permits in Oregon are subject to the air 
quality analysis requirements in Division 225. In the submission, the 
State added language to the procedural requirements in OAR 340-225-
0030. Significant increases in total particulate matter emissions \15\ 
do not require an air quality impact analysis for comparison to 
significant impact levels, PSD increments, and ambient air quality 
standards. However, if applicable, the Oregon DEQ may require an owner 
or operator to speciate particulate matter and conduct an air quality 
analysis for PM10 and PM2.5. We propose to 
approve this clarification because it is appropriate to focus air 
quality analyses on PM2.5 and PM10 for comparison 
to the PM10 and PM2.5 NAAQS.
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    \15\ Significant in this context means equal to or greater than 
the SER.
---------------------------------------------------------------------------

    Oregon also corrected the rule language addressing analyses to 
determine compliance with the NAAQS, PSD increments, visibility and 
other requirements in OAR 340-225-0050 and OAR 340-225-0070 to 
consistently refer to a ``proposed source or modification.'' We propose 
to approve the changes because they correct inadvertent errors from a 
prior State rulemaking.

I. Division 226--General Emission Standards

    The State revised the general emission standards for highest and 
best practicable treatment and control in Division 226. Specifically, 
Oregon revised OAR 340-226-0010 to state that the Oregon DEQ may 
establish permit conditions to prevent the degradation of air quality. 
Oregon added language to OAR 340-226-0140 to make clear that any air 
quality analysis must be conducted in accordance with the procedures in 
Division 225. The revisions also included changes to the same rule 
section clarifying that for existing sources, the permitting authority 
may conduct monitoring or modeling (or may require the source to 
conduct monitoring or modeling) to determine whether the source's 
emissions will cause or contribute to a new exceedance of an ambient 
air quality standard. In addition, OAR 340-226-0240 historically phased 
in tighter grain loading standards to limit particulate matter 
emissions from sources other than fuel and refuse burning.\16\ The 
tighter limits are now in effect and the State has removed the obsolete 
phase-in language. We propose to approve the changes because they are 
designed to improve permit program implementation and protect the 
NAAQS.
---------------------------------------------------------------------------

    \16\ Fuel and refuse burning are regulated in Divisions 228 and 
230, respectively.
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J. Division 228--Requirements for Fuel Burning Equipment

    Oregon made similar changes to the fuel burning equipment 
requirements in Division 228 to remove obsolete language that 
historically phased in tighter emission limits. We propose to approve 
these housekeeping changes.

K. Division 232--Emission Standards for VOC Point Sources

    Oregon revised the non-categorical emission standards at OAR 340-
232-0040 to clarify that certain large VOC sources with no categorical 
Reasonably Available Control Technology (RACT) requirements are subject 
to case-by-case RACT determination by the Oregon DEQ. If a source is 
located in the Portland-Vancouver or Salem-Keizer areas \17\ and has 
the potential to emit over 100 tons per year of VOC from aggregated, 
non-regulated emissions units based on the design capacity or maximum 
production or throughput capacity of the source operating 8,760 hours 
per year without the use of control devices or limits on hours of 
operation, it is subject to case-by-case RACT. A source that has 
complied with the NSR requirements in Division 224 and is subject to 
Best Available Control Technology (BACT) or Lowest Achievable Emission 
Rate (LAER) requirements is presumed to have met the Division 232 RACT 
requirements. In addition, a source may request relief from RACT by 
demonstrating to the Oregon DEQ that the aggregated, non-regulated 
emissions units are unable to emit more than 100 tons per year of VOC, 
based on the design capacity or maximum production or throughput 
capacity of the source operating 8,760 hours per year without the use 
of control devices. We propose to approve the changes because they make 
clear that a VOC PSEL is not sufficient to avoid this non-categorical 
RACT requirement.
---------------------------------------------------------------------------

    \17\ See OAR 340-232-0020.
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    The State also revised the surface coating in manufacturing 
requirements at OAR 340-232-0160 to clarify that surface coating 
operations not specifically listed in the rule are subject to OAR 340-
232-0040. But the requirements do not apply to certain very small VOC 
sources.\18\ We propose to approve these minor changes.
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    \18\ Specifically, sources whose VOC potential to emit before 
add on controls from activities identified in section (5) is less 
than 10 tons per year; sources with VOC actual emissions before add 
on controls from activities identified in section (5) are less than 
3 pounds per hour; sources with VOC actual emissions before add on 
controls from activities identified in section (5) are less than 15 
pounds per day. See OAR 340-232-0160.
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L. Division 234--Emission Standards for Wood Products Industries

    Oregon revised the emission standards for kraft pulp mills to 
clarify that sources subject to the particulate emission standards in 
Division 234 are not also subject to the grain loading standards in 
Divisions 226 and 228 and the opacity limits in Division 208. We 
propose to approve this clarification.

M. Division 21--General Emission Standards for Particulate Matter

    The Oregon SIP contains certain expired rules that historically 
addressed industrial contingency requirements for selected 
PM10 nonattainment areas in Oregon (OAR 340-021-0200 through 
0245). In the submission, Oregon requested to remove the rule sections 
from the SIP because they have expired and are no longer in effect as a 
matter of State law. The expired rule sections

[[Page 22369]]

applied only to coarse particulate (PM10) nonattainment 
areas that failed to attain the 1987 PM10 NAAQS by the 
applicable attainment date of December 31, 1994.\19\ There are no areas 
in which these rules apply because all PM10 nonattainment 
areas in Oregon have attained the PM10 standard and have 
been redesignated to attainment.\20\ We propose to approve the State's 
request to remove the Division 21 rules from the SIP because the rules 
are expired, apply nowhere in Oregon, were repealed by the State in 
1998, no longer exist as a matter of State law, and as such, removal 
will not interfere with any applicable requirements concerning 
attainment and reasonable further progress, or any other applicable 
requirement of this chapter.
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    \19\ See 57 FR 13498, April 16, 1992, at page 13537. The 
applicable attainment date for PM10 nonattainment areas 
classified as ``moderate'' was December 31, 1994. All designated 
PM10 areas in Oregon were classified as moderate.
    \20\ See Oregon area designations codified at 40 CFR 81.338.
---------------------------------------------------------------------------

III. Proposed Action

    The EPA is proposing to approve revisions to the Oregon SIP 
submitted on March 27, 2023.\21\ The following paragraphs detail our 
proposed incorporations by reference.
---------------------------------------------------------------------------

    \21\ We note that we have not described minor wording changes 
and clarifications that do not alter the meaning of the rules. We 
also note that we intend to address the submitted changes to 
Division 214, related to stationary source reporting requirements, 
in a separate action.
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A. Rule Sections To Be Incorporated by Reference

    The EPA is proposing to incorporate specific Oregon administrative 
rule sections by reference. Upon final action, the regulatory portion 
of the Oregon SIP, at 40 CFR 52.1970(c), will include the following 
provisions, State effective March 1, 2023:
     OAR 340-200-0020 General Air Quality Definitions (defining 
terms used in the Oregon air quality regulations);
     OAR 340-200-0025 Abbreviations and Acronyms (defining 
abbreviations and acronyms used in the Oregon air quality regulations);
     OAR 340-200-0035 Reference Materials (specifying the title 
and version of each reference material used in the Oregon air quality 
regulations);
     OAR 340-204-0300 Designation of Sustainment Areas \22\ 
(identifying the areas in Oregon designated as sustaining the relevant 
air quality standard);
---------------------------------------------------------------------------

    \22\ Oregon revised the regulatory note only, not the regulatory 
text.
---------------------------------------------------------------------------

     OAR 340-204-0310 Designation of Reattainment Areas \23\ 
(identifying the areas in Oregon designated as reattaining the relevant 
air quality standard);
---------------------------------------------------------------------------

    \23\ Oregon revised the regulatory note only, not the regulatory 
text.
---------------------------------------------------------------------------

     OAR 340-206-0010 Introduction (establishing significant 
harm levels for pollutants in areas based on priority level);
     OAR 340-208-0110 Visible Air Contaminant Limitations 
(establishing limits and test methods for visible emissions);
     OAR 340-209-0080 Issuance or Denial of a Permit 
(specifying procedures for issuing and denying permits, including how 
to request a hearing to contest a permit decision);
     OAR 340-210-0100 Registration in General (identifying 
categories of sources that are required to register with the Oregon 
DEQ);
     OAR 340-210-0205 Notice of Construction and Approval of 
Plans: Applicability and Requirements, except paragraph (3) (listing 
source types and activities that require notice to the Oregon DEQ prior 
to construction);
     OAR 340-210-0225 Notice of Construction and Approval of 
Plans: Types of Construction/Modification Changes (establishing the 
activities that qualify for each type of notice of construction);
     OAR 340-210-0230 Notice of Construction and Approval of 
Plans: Notice to Construct Application (requiring the specific 
information to be submitted in an application);
     OAR 340-210-0240 Notice of Construction and Approval of 
Plans: Construction Approval (specifying what level of approval from 
Oregon DEQ is needed before a source may begin construction);
     OAR 340-210-0250 Notice of Construction and Approval of 
Plans: Approval to Operate (specifying what is required of a source to 
obtain approval to operate);
     OAR 340-214-0110 Reporting: Request for Information 
(requiring sources to respond to Oregon DEQ requests for information);
     OAR 340-214-0114 Reporting: Records; Maintaining and 
Reporting (detailing when and how to record and report data);
     OAR 340-214-0130 Reporting: Information Exempt from 
Disclosure (establishing that trade secrets and other eligible data may 
be exempt from disclosure);
     OAR 340-216-0020 Applicability and Jurisdiction 
(identifying source categories subject to air contaminant discharge 
permits);
     OAR 340-216-0025 Types and Permits (identifying the types 
of air contaminant discharge permits);
     OAR 340-216-0040 Application Requirements (spelling out 
the information required to be included in permit applications);
     OAR 340-216-0054 Short Term Activity ACDPs (listing the 
pilot and other time-limited activities that may be eligible for a 
short term activity ACDP);
     OAR 340-216-0056 Basic ACDPs (identifying the contents of 
a basic ACDP);
     OAR 340-216-0060 General Air Contaminant Discharge Permits 
(identifying the contents of a general ACDP);
     OAR 340-216-0064 Simple ACDPs (identifying the contents of 
a simple ACDP);
     OAR 340-216-0066 Standard ACDPs (identifying the contents 
of a standard ACDP);
     OAR 340-216-0068 Simple and Standard ACDP Attachments 
(allowing Oregon DEQ to add requirements to existing simple and 
standard ACDP permits);
     OAR 340-216-0082 Expiration, Termination, Reinstatement or 
Revocation of an ACDP (regulating when and how ACDPs expire, are 
terminated, reinstated or revoked);
     OAR 340-216-0084 Department Initiated Modification 
(establishing a means by which Oregon DEQ may modify an ACDP when 
needed);
     OAR 340-216-8010 Table 1--Activities and Sources (listing 
which source categories and associated activities must obtain an ACDP);
     OAR 340-216-8020 Table 2--Air Contaminant Discharge 
Permits, except paragraph (2) and Table 2 (requiring sources to pay 
ACDP fees to the Oregon DEQ);
     OAR 340-222-0020 Applicability and Jurisdiction (requiring 
that plant site emission limits are included in most ACDPs and title V 
operating permits);
     OAR 340-222-0035 General Requirements for Establishing All 
PSELs (describing how plant site emission limits are established and 
how they are revised);
     OAR 340-222-0041 Annual PSELs (prescribing how annual 
plant site emission limits are established on a source-specific basis);
     OAR 340-222-0042 Short Term PSEL (establishing short term 
limits for sources located in areas with an established short term 
significant emission rate);
     OAR 340-222-0046 Netting Basis (establishes netting basis 
requirements);
     OAR 340-224-0030 New Source Review Procedural Requirements 
(establishing application and processing procedures for new source 
review permits);

[[Page 22370]]

     OAR 340-224-0520 Net Air Quality Benefit Emission Offsets: 
Requirements for Demonstrating Net Air Quality Benefit for Ozone Areas 
(requiring certain sources to offset emissions in areas with ozone 
problems);
     OAR 340-224-0530 Net Air Quality Benefit Emission Offsets: 
Requirements for Demonstrating Net Air Quality Benefit for Non-Ozone 
Areas (requiring sources to offset emissions in areas with particulate 
matter problems);
     OAR 340-225-0030 Procedural Requirements (prescribing the 
procedures for air quality analysis);
     OAR 340-225-0050 Requirements for Analysis in PSD Class II 
and Class III Areas (establishing the modeling requirements for sources 
in PSD class II and III areas);
     OAR 340-225-0070 Requirements for Demonstrating Compliance 
with Air Quality Related Values Protection (describing how to comply 
with limits established for national parks, wilderness, and other 
areas);
     OAR 340-226-0100 Highest and Best Practicable Treatment 
and Control: Policy and Application (requiring appropriate conditions 
in permits to control and treat emissions to the highest extent);
     OAR 340-226-0130 Highest and Best Practicable Treatment 
and Control: Typically Achievable Control Technology (TACT) (laying out 
when and how the Oregon DEQ will make typically achievable control 
technology determinations);
     OAR 340-226-0140 Highest and Best Practicable Treatment 
and Control: Additional Control Requirements for Stationary Sources of 
Air Contaminants (providing that the Oregon DEQ will establish 
additional control requirements to protect the NAAQS, visibility, and 
other public health and environmental goals);
     OAR 340-226-0210 Grain Loading Standards: Particulate 
Emission Limitations for Sources Other Than Fuel Burning Equipment, 
Refuse Burning Equipment and Fugitive Emissions (establishing 
particulate emission standards for non-fuel burning equipment);
     OAR 340-228-0210 General Emission Standards for Fuel 
Burning Equipment: Grain Loading Standards (setting grain loading 
standards for fuel-burning equipment);
     OAR 340-232-0030 Definitions (defining terms used in the 
rules establishing emission standards for VOC point sources);
     OAR 340-232-0040 General Non-Categorical Requirements 
(spelling out general case-by-case RACT requirements for VOC point 
sources);
     OAR 340-232-0090 Bulk Gasoline Terminals Including Truck 
and Trailer Loading (VOC emission limits for bulk gasoline terminals);
     OAR 340-232-0160 Surface Coating in Manufacturing (VOC 
emission limits for surface coating operations);
     OAR 340-232-0170 Aerospace Component Coating Operations 
(VOC emission limits for component coating in the aerospace industry);
     OAR 340-234-0010 Definitions except (8) and (10) (defining 
terms used in the rules establishing emission standards for the wood 
products industry);
     OAR 340-234-0210 Kraft Pulp Mills: Emission Limitations, 
except references to total reduced sulfur (setting emission limits for 
kraft pulp mills);
     OAR 340-236-8010 Hot Mix Asphalt Plants: Table--Process 
Weight Table (requiring hot mix asphalt plants to comply with specific 
process weight discharge rates);

B. Rule Sections To Be Removed From Incorporation by Reference

    The EPA is proposing to remove from incorporation by reference the 
following Oregon administrative rule sections:
     OAR 340-210-0215 Notice of Construction and Approval of 
Plans: Requirement, State effective April 16, 2015 (requirements to 
notify the Oregon DEQ prior to constructing or modifying a subject 
source);
     OAR 340-222-0040 Generic Annual PSEL, State effective 
April 16, 2015 (establishing generic plant site emission limits for 
subject sources that emit less than the significant emission rate);
     OAR 340-021-200 Purpose, State effective May 1, 1995 
(describing the purpose of contingency control requirements for 
existing industrial sources in coarse particulate matter nonattainment 
areas);
     OAR 340-021-205 Relation to Other Rules, State effective 
March 10, 1993 (describing the relation of contingency control 
requirements to other regulations);
     OAR 340-021-210 Applicability, State effective March 10, 
1993 (stating that contingency control requirements shall apply if the 
EPA determines an area has failed to attain the PM10 
standard by the applicable attainment date);
     OAR 340-021-215 Definitions, State effective March 10, 
1993 (establishing definitions used in the contingency control 
requirements);
     OAR 340-021-220 Compliance Schedule for Existing Sources, 
State effective March 10, 1993 (setting the compliance schedule for 
sources to install emissions control systems as a contingency control 
requirement);
     OAR 340-021-225 Wood-Waste Boilers, State effective March 
10, 1993 (limiting emissions from wood-waste boilers to a specific rate 
as a contingency control requirement);
     OAR 340-021-230 Wood Particle Dryers at Particleboard 
Plants, State effective March 10, 1993 (limiting emissions from wood 
particle dryers to a specific rate as a contingency control 
requirement);
     OAR 340-021-235 Hardboard Manufacturing Plants, State 
effective March 10, 1993 (limiting emissions from hardboard 
manufacturing plants to a specific rate as a contingency control 
requirement);
     OAR 340-021-240 Air Conveying Systems, State effective 
March 10, 1993 (limiting emissions from air conveying systems to a 
specific rate as a contingency control requirement); and
     OAR 340-021-245 Fugitive Emissions, State effective March 
10, 1993 (requiring wood products manufacturing plants to limit 
fugitive emissions as a contingency control requirement).

IV. Incorporation by Reference

    In this document, the EPA is proposing to include in a final 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 provisions described in section III. of this preamble. 
The EPA has made, and will continue to make, these documents generally 
available through https://www.regulations.gov and at the EPA Region 10 
Office (please contact the person identified in the FOR FURTHER 
INFORMATION CONTACT section of this preamble for more information).
    Also in this document, the EPA is proposing to remove in a final 
rule, regulatory text from incorporated by reference, as described in 
section III. of this preamble.

V. 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 Clean Air Act 
and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). 
Thus, in reviewing SIP submissions, EPA's role is to approve State 
choices, provided that they meet the criteria of

[[Page 22371]]

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 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 proposed rule would not have Tribal implications 
and would 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 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 air agency did not evaluate environmental justice 
considerations as part of its SIP submission; the Clean Air Act 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. 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 proposed action, and there is no information 
in the record inconsistent with the stated goal of Executive Order 
12898 of achieving environmental justice 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, 
Particulate matter, Reporting and recordkeeping requirements, Sulfur 
oxides, Volatile organic compounds.

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

    Dated: March 26, 2024.
Casey Sixkiller,
Regional Administrator, Region 10.
[FR Doc. 2024-06807 Filed 3-29-24; 8:45 am]
BILLING CODE 6560-50-P