Air Plan Approval; Wyoming; R-35 Wyoming Air Quality Standards and Regulations Rule Package

<RULE> ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Part 52</CFR> <DEPDOC>[EPA-R08-OAR-2025-0204; FRL-12942-02-R8]</DEPDOC> <SUBJECT>Air Plan Approval; Wyoming; R-35 Wyoming Air Quality Standards and Regulations Rule Package</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Environmental Protection Agency (EPA). <HD SOURCE="HED">ACTION:</HD> Direct final rule. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The Environmental Protection Agency (EPA) is taking direct final action to approve revisions to the Wyoming State Implementation Plan (SIP) submitted by the Wyoming Department of Environmental Quality (WDEQ) on December 16, 2024. WDEQ requested the EPA approve the revised rules for Chapters 2, 3, 4, 8, and 14 in the Wyoming Air Quality Standards and Regulations (WAQSR). The revised rules include non-substantive updates to rule language that ensure consistent grammar, formatting, and written clarity as well as updated references to the Code of Federal Regulations (CFR). The EPA is taking this action pursuant to the Clean Air Act (CAA). </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This direct final rule is effective on November 10, 2025, without further notice, unless the EPA receives adverse comments by October 14, 2025. If adverse comments are received, the EPA will publish a timely withdrawal of the direct final rule in the <E T="04">Federal Register</E> informing the public that the rule will not take effect. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Submit your comments, identified by Docket ID No. EPA-R08-OAR-2025-0204, to the Federal Rulemaking Portal: <E T="03">https://www.regulations.gov.</E> Follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from <E T="03">https://www.regulations.gov.</E> The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission ( <E T="03">i.e.,</E> on the web, cloud, or other file sharing system). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit <E T="03">https://www.epa.gov/dockets/commenting-epa-dockets.</E> <E T="03">Docket:</E> The EPA has established a docket for this action under Docket ID No. EPA-R08-OAR-2025-0204. All documents in the docket are listed on the <E T="03">https://www.regulations.gov</E> website. Although listed in the index, some information is not publicly available, <E T="03">e.g.,</E> CBI or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the internet and will be publicly available only in hard copy form. Publicly available docket materials are available through <E T="03">https://www.regulations.gov,</E> or please contact the person identified in the <E T="02">FOR FURTHER INFORMATION CONTACT</E> section for additional availability information. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Chelsea Cancino, Air and Radiation Division, EPA, Region 8, Mailcode 8ARD-IO, 1595 Wynkoop Street, Denver, Colorado 80202-1129, telephone number: (303) 312-6276, email address: <E T="03">cancino.chelsea@epa.gov.</E> </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> Throughout this document “we,” “us,” and “our” means the EPA. <HD SOURCE="HD1">I. Background</HD> WDEQ reviewed its regulations and concluded that rule revisions were needed to modify the wording of selected text to correct typographical errors and reflect new formatting guidelines. WDEQ adopted these various minor revisions and updated their rules on April 30, 2024, and then requested that the EPA approve these revisions into the Wyoming SIP in a submittal dated December 16, 2024. <HD SOURCE="HD1">II. The EPA's Evaluation</HD> WDEQ has requested that the EPA approve revised rules under Chapter 2, 3, 4, 8, and 14 of the WAQSR. These revisions adopt minor changes in rule language to meet updated state style and formatting guidelines. These revisions also include Incorporation by Reference (IBR) material in Wyoming's SIP. IBR allows state agencies to comply with the requirement to adopt certain Federal rules by referring to materials already published in the CFR. In this SIP revision, Wyoming is incorporating by reference 40 CFR parts 50, 51, 53, 60, 81, and 93 as published on July 1, 2023. No terms or definitions were added or removed from the revised sections. Since the revisions are minor in nature, do not make this rule less stringent, and do not affect the scope or intent of the rules, the EPA finds that the revisions to these chapters are approvable. With regard to the approval of WAQSR Chapter 02, Section 04, “Ambient Standards for Sulfur Oxides,” we note that the December 16, 2024 submittal supersedes the revisions to this section contained in WDEQ's February 10, 2014 SIP submittal that the EPA had not previously acted on. <SU>1</SU> <FTREF/> <FTNT> <SU>1</SU>  See 80 FR 45608, July 31, 2015, in which the EPA did not act on the State's proposed revisions to WAQSR Chapter 02, Section 04(a), 4(a)(i) and 4(a)(ii). These provisions are removed from Chapter 02, Section 04 as submitted December 16, 2024, and the EPA considers this submittal to supersede that of February 10, 2014. </FTNT> <HD SOURCE="HD1">III. Final Action</HD> The EPA is approving the December 16, 2024, submission by WDEQ as a revision to the Wyoming SIP. Specifically, the EPA is approving updates to WAQSR Chapters 2, 3, 4, 8, and 14 as detailed in table 1 below. We are publishing this action without a prior proposed rule because we view these SIP revisions as noncontroversial and anticipate no relevant adverse comment. The revisions are administrative in nature and do not constitute substantive changes to Wyoming's SIP. However, in the “Proposed Rules” section of this <E T="04">Federal Register</E> publication, we are publishing a separate action to approve the revisions to Wyoming's SIP submitted by the WDEQ on December 16, 2024 if adverse comments are received on this direct final rule. We will not institute a second comment period on this action. Any parties interested in commenting must do so at this time. For further information about commenting on this rule, see the <E T="02">ADDRESSES</E> section of this document. If the EPA receives adverse comment, we will publish a timely withdrawal in the <E T="04">Federal Register</E> informing the public that this direct final rule, or the relevant provisions of this rule, will not take effect. We would address all public comments in any subsequent final rule based on the proposed rule. If we receive adverse comment on a distinct provision of this rulemaking, we will publish a timely withdrawal in the <E T="04">Federal Register</E> indicating which provisions we are withdrawing. The provisions that are not withdrawn will become effective on the date set out above, notwithstanding adverse comment on any other provision. <GPOTABLE COLS="4" OPTS="L2,nj,i1" CDEF="xs66,r50,r50,xs62"> <TTITLE>Table 1—EPA's Evaluation</TTITLE> <CHED H="1">Rule No.</CHED> <CHED H="1">Rule title</CHED> <CHED H="1">Revision summary</CHED> <CHED H="1"> EPA's proposed action </CHED> <ROW EXPSTB="03" RUL="s"> <E T="02">Chapter 02. Ambient Standards</E> </ENT> </ROW> <ROW EXPSTB="00"> <ENT I="01">Section 02</ENT> <ENT>Ambient Standards for Particulate Matter</ENT> <ENT>Non-substantive formatting revisions</ENT> <ENT>Approval.</ENT> </ROW> <ROW> <ENT I="01">Section 03</ENT> <ENT>Ambient Standards for Nitrogen Oxides</ENT> <ENT>Non-substantive formatting revisions</ENT> <ENT>Approval.</ENT> </ROW> <ROW> <ENT I="01">Section 04</ENT> <ENT>Ambient Standards for Sulfur Oxides</ENT> <ENT>Non-substantive formatting revisions</ENT> <ENT>Approval.</ENT> </ROW> <ROW> <ENT I="01">Section 05</ENT> <ENT>Ambient Standards for Carbon Monoxide</ENT> <ENT>Non-substantive formatting revisions</ENT> <ENT>Approval.</ENT> </ROW> <ROW> <ENT I="01">Section 06</ENT> <ENT>Ambient Standards for Ozone</ENT> <ENT>Non-substantive formatting revisions</ENT> <ENT>Approval.</ENT> </ROW> <ROW> <ENT I="01">Section 08</ENT> <ENT>Ambient Standards for Suspended Sulfates</ENT> <ENT>Non-substantive formatting revisions</ENT> <ENT>Approval.</ENT> </ROW> <ROW> <ENT I="01">Section 10</ENT> <ENT>Ambient Standards for Lead</ENT> <ENT>Non-substantive formatting revisions</ENT> <ENT>Approval.</ENT> </ROW> <ROW RUL="s"> <ENT I="01">Section 12</ENT> <ENT>Incorporation by Reference</ENT> <ENT>Updated adoption of the CFR as of July 1, 2023 and associated weblink</ENT> <ENT>Approval.</ENT> </ROW> <ROW EXPSTB="03" RUL="s"> <ENT I="21"> <E T="02">Chapter 03. General Emission Standards</E> </ENT> </ROW> <ROW EXPSTB="00"> <ENT I="01">Section 02</ENT> <ENT>Emission Standards for Particulate Matter</ENT> <ENT>Non-substantive formatting revisions</ENT> <ENT>Approval.</ENT> </ROW> <ROW> <ENT I="01">Section 03</ENT> <ENT>Emission Standards for Nitrogen Oxides</ENT> <ENT>Non-substantive formatting revisions</ENT> <ENT>Approval.</ENT> </ROW> <ROW> <ENT I="01">Section 04</ENT> <ENT>Emission Standards for Sulfur Oxides</ENT> <ENT>Non-substantive formatting revisions</ENT> <ENT>Approval.</ENT> </ROW> <ROW> <ENT I="01">Section 05</ENT> <ENT>Emission Standards for Carbon Monoxide</ENT> <ENT>Non-subs ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 26k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━