Air Plan Approval; Wyoming; Revisions to Regional Haze State Implementation Plan

<RULE> ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Part 52</CFR> <DEPDOC>[EPA-R08-OAR-2022-0536; FRL-11829-02-R8]</DEPDOC> <SUBJECT>Air Plan Approval; Wyoming; Revisions to Regional Haze State Implementation Plan</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Environmental Protection Agency (EPA). <HD SOURCE="HED">ACTION:</HD> Final rule. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The Environmental Protection Agency (EPA) is approving a State Implementation Plan (SIP) revision submitted by the State of Wyoming on December 30, 2022, and supplemented on August 31, 2023, and November 16, 2023, addressing regional haze for Jim Bridger Units 1 and 2 (Wyoming 2022 SIP revision). Wyoming's 2022 SIP revision provides oxides of nitrogen (NO <E T="52">X</E> ) emission and heat input limits that collectively allow for identical reasonable progress as part of the long term strategy during the first implementation period as the associated emission limits in the existing SIP for Jim Bridger Units 1 and 2. The EPA is also approving monthly and annual NO <E T="52">X</E> and sulfur dioxide (SO <E T="52">2</E> ) emission limits for Jim Bridger Units 1 through 4 that were included in Wyoming's 2022 SIP revision. The EPA is taking this action pursuant to the Clean Air Act (CAA or the Act). </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This rule is effective on September 8, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> The EPA has established a docket for this action under Docket ID No. EPA-R08-OAR-2022-0536. 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> Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the internet and will be publicly available only in hard copy form. Publicly available docket materials are available through <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> Jaslyn Dobrahner, Air and Radiation Division, EPA, Region 8, Mailcode 8P-ARD, 1595 Wynkoop Street, Denver, Colorado 80202-1129, telephone number: (303) 312-6252, email address: <E T="03">dobrahner.jaslyn@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. What is being addressed in this document?</HD> The EPA is approving Wyoming's 2022 SIP revision addressing regional haze long term strategy for the first implementation period at Jim Bridger Units 1 and 2. As required by section 169A of the CAA, the regional haze rule (RHR) calls for state and federal agencies to work together to improve visibility in 156 national parks and wilderness areas, known as mandatory Class I Federal areas. <SU>1</SU> <FTREF/> The rule requires the states, in coordination with the EPA, the National Park Service (NPS), the Fish and Wildlife Service, the Forest Service, and other interested parties, to develop and implement air quality protection plans to reduce the pollution that causes visibility impairment in mandatory Class I Federal areas. Visibility impairing pollutants include fine and coarse particulate matter (PM) ( <E T="03">e.g.,</E> sulfates, nitrates, organic carbon, elemental carbon, and soil dust) and their precursors ( <E T="03">e.g.,</E> SO <E T="52">2</E> , NO <E T="52">X</E> , and, in some cases, volatile organic compounds (VOC) and ammonia (NH <E T="52">3</E> )). As discussed in further detail in our proposed rule, this document, and the accompanying Response to Comments (RTC) document, the EPA finds that Wyoming submitted a regional haze SIP revision addressing long term strategy at Jim Bridger Units 1 and 2 that meets the regional haze requirements for the first implementation period. The State's submission, the proposed rule, and the RTC document can be found in the docket for this action. <FTNT> <SU>1</SU>   <E T="03">See</E> 40 CFR part 81, subpart D. </FTNT> <HD SOURCE="HD1">II. Background</HD> On December 30, 2022, Wyoming submitted a revision to its SIP to address regional haze for the first implementation period for Jim Bridger, Units 1 through 4 in accordance with the requirements of the CAA's regional haze program established by CAA sections 169A and 169B and 40 CFR 51.308. <SU>2</SU> <FTREF/> <FTNT> <SU>2</SU>  The State supplemented the SIP revision on August 31, 2023, and November 16, 2023. </FTNT> On April 10, 2024, the EPA proposed to approve Wyoming's 2022 SIP revision which will replace the previously approved NO <E T="52">X</E> emission limit of 0.07 pounds per million British Thermal Units (lb/MMBtu) (30-day rolling average) at Jim Bridger Units 1 and 2 for Wyoming's regional haze long-term strategy. <SU>3</SU> <FTREF/> Specifically, the Wyoming 2022 SIP revision amends the State's previously approved long-term strategy for the first regional haze implementation period and requires Jim Bridger Units 1 and 2 to meet NO <E T="52">X</E> emission limits of 0.12 lb/MMBtu (30-day rolling average) and annual NO <E T="52">X</E> limits of 1,314 tons/year for each unit, and a heat input limit of 21,900,000 MMBtu/year per unit by January 1, 2024. Ultimately, the Wyoming 2022 SIP revision finds the modified NO <E T="52">X</E> emission and heat input limits to be sufficient for reasonable progress as part of the long-term strategy during the first implementation period in lieu of the existing emission limits associated with the installation of SCR controls approved and codified by EPA at 40 CFR 52.2636(c)(1). <SU>4</SU> <FTREF/> Wyoming also included in Wyoming's 2022 SIP revision NO <E T="52">X</E> and SO <E T="52">2</E> monthly and annual emission limits for Jim Bridger Units 1-4. The Wyoming 2022 SIP revision reflects changes to Chapters 7 and 8 of Wyoming's regional haze SIP narrative  <SU>5</SU> <FTREF/> and incorporates certain conditions of Wyoming air quality permits #P0025809 and #P0036941. <FTNT> <SU>3</SU>  89 FR 25200 (April 10, 2024). </FTNT> <FTNT> <SU>4</SU>  79 FR 5032 (January 30, 2014). </FTNT> <FTNT> <SU>5</SU>  State of Wyoming, “Addressing Regional Haze Visibility Protection For The Mandatory Federal Class I Areas Required Under 40 CFR 51.309,” Revised May 23, 2022 (“Wyoming 2022 SIP revision”). </FTNT> Our April 10, 2024, proposed rule provided background on the requirements of the CAA and RHR, a summary of Wyoming's regional haze submittals and related EPA actions, and the EPA's rationale for its proposed action. <SU>6</SU> <FTREF/> That background and rationale will not be restated in full here; see the proposed rule preamble for details. <SU>7</SU> <FTREF/> <FTNT> <SU>6</SU>  89 FR 25200 (April 10, 2024). </FTNT> <FTNT> <SU>7</SU>  89 FR 25200 (April 10, 2024). </FTNT> <HD SOURCE="HD1">III. Public Comments and EPA Responses</HD> The public comment period on the proposal closed on May 10, 2024. During the public comment period, we received three comments on our proposal; two in support and one in opposition. The commenters were:  <SU>8</SU> <FTREF/> Idaho Power Company, and PacifiCorp. <SU>11</SU> <FTREF/> The full text of comments received is included in the publicly posted docket associated with this action at <E T="03">https://www.regulations.gov.</E> Our RTC document, which is also included in the docket associated with this action, provides detailed responses to all significant comments received. <FTNT> <SU>8</SU>  We received one comment that was not related to the proposed rulemaking. </FTNT> <FTNT> <SU>9</SU>  Letter dated May 10, 2024. </FTNT> <FTNT> <SU>10</SU>  Letter dated May 7, 2024. </FTNT> <FTNT> <SU>11</SU>  Letter dated May 10, 2024. </FTNT> <HD SOURCE="HD1">IV. Final Action</HD> For the reasons stated in the proposed rule, we find that the Wyoming 2022 SIP revision requiring NO <E T="52">X</E> emission and heat input limits, are sufficient for reasonable progress during the first planning period and that the NO <E T="52">X</E> emission limits associated with the installation of SCR controls are no longer required. Therefore, we are approving Wyoming's 2022 SIP revision for the NO <E T="52">X</E> reasonable progress analysis and determination for Jim Bridger Units 1 and 2, including the associated emission and operational limitations, compliance dates, and monitoring, recordkeeping and reporting requirements as well as the separate monthly and annual NO <E T="52">X</E> and SO <E T="52">2</E> emission limits. Specifically, the EPA is approving the following as federally enforceable elements of the Wyoming 2022 SIP revision for Jim Bridger Units 1-4: • The NO <E T="52">X</E> emission limits found in Wyoming air quality permit #P0036941 (Condition 9 for NO <E T="52">X</E> lb/MMBtu and tons/year emission limits) for Units 1 and 2. • The NO <E T="52">X</E> and SO <E T="52">2</E> emission limits found in Wyoming air quality permit #P0025809 (Condition 7 for pounds per hour (lb/hr) and Condition 9 for tons/year) for Units 1-4. • The operational limit on annual heat input (based on a 12-month rolling average of hourly heat input values) found in Wyoming air quality permit #P0036941 (Condition 19). • The compliance dates found in Wyoming air quality permit #P0036941 (Conditions 11 and 16) requiring that Units 1 and 2 comply with NO <E T="52">X</E> emission rates in lb/MMBtu (30-day rolling average) and tons/year as well as an annual heat input in MMBtu/year; and permit #P002580 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 29k characters. 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