Air Plan Approval; Texas and Oklahoma; Texas Regional Haze Plans for the First and Second Implementation Periods and Five-Year Progress Report; Oklahoma Regional Haze Plan for the First Implementation Period

ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Part 52</CFR> <DEPDOC>[EPA-R06-OAR-2025-0197; FRL-12217-01-R6]</DEPDOC> <SUBJECT>Air Plan Approval; Texas and Oklahoma; Texas Regional Haze Plans for the First and Second Implementation Periods and Five-Year Progress Report; Oklahoma Regional Haze Plan for the First Implementation Period</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Environmental Protection Agency (EPA). <HD SOURCE="HED">ACTION:</HD> Proposed rule and withdrawal of proposed rule. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The Environmental Protection Agency (EPA) is proposing to approve regional haze State Implementation Plan (SIP) revisions submitted by the Texas Commission on Environmental Quality (TCEQ), dated March 20, 2014, and July 20, 2021, as satisfying applicable requirements under the Clean Air Act (CAA or Act) and EPA's Regional Haze Rule (RHR). Additionally, the EPA is proposing to approve portions of the 2009 Texas Regional Haze SIP submission and portions of the 2010 Oklahoma Regional Haze SIP submission that relate to reasonable progress requirements for the first planning period from 2007 through 2018. Finally, the EPA is also withdrawing its 2023 proposed disapprovals regarding Texas's and Oklahoma's first planning period SIPs and its 2024 proposed action regarding Texas's second planning period SIP. The EPA is taking this action pursuant to sections 110 and 169A of the Act. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> Written comments must be received on or before June 23, 2025. <E T="03">Withdrawal:</E> As of May 23, 2025, the proposed rule published October 15, 2024, at 89 FR 83338 is withdrawn, and the proposed disapprovals for portions of Texas and Oklahoma SIPs included as part of the proposed rule published on July 26, 2023, at 88 FR 48152 are withdrawn. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Submit your comments, identified by Docket No. EPA-R06-OAR-2025-0197, at <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">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, please contact Michael Feldman, 214-665-9793, <E T="03">Feldman.Michael@epa.gov.</E> For 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 index to the docket for this action is available electronically at <E T="03">www.regulations.gov.</E> While all documents in the docket are listed in the index, some information may not be publicly available due to docket file size restrictions or content ( <E T="03">e.g.,</E> CBI). <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Michael Feldman, U.S. Environmental Protection Agency, Region 6, Air and Radiation Division, SO <E T="52">2</E> and Regional Haze Section (ARSH), 1201 Elm Street, Suite 500, Dallas, Texas 75270, 214-665-9793, <E T="03">Feldman.Michael@epa.gov.</E> We encourage the public to submit comments via <E T="03">https://www.regulations.gov.</E> Please call or email the contact listed above if you need alternative access to material indexed but not provided in the docket. </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> Throughout this document wherever “we,” “us,” or “our” is used, we mean the EPA. <HD SOURCE="HD1">I. What action is EPA proposing?</HD> On March 19, 2009, Texas submitted a revision to its SIP to address regional haze for the first planning period (2009 Plan). Texas made this SIP submission to satisfy the requirements of the CAA's regional haze program pursuant to CAA sections 169A and 169B and 40 CFR 51.308. The EPA is proposing to approve the portions of Texas's 2009 Plan which the EPA previously disapproved related to certain reasonable progress requirements under 40 CFR 51.308(d)(1) through (3). <SU>1</SU> <FTREF/> The disapproval was subsequently vacated by the Fifth Circuit. The EPA is also proposing to approve the portions of Oklahoma's first planning period SIP that the State submitted in 2010 (2010 Plan) that address certain requirements under 40 CFR 51.308(d)(1). EPA's disapproval of these portions of the Oklahoma plan was also vacated by the Fifth Circuit as part of the same action that vacated portions of our disapproval of Texas's 2009 Plan. <FTNT> <SU>1</SU>  The BART requirements for EGUs were disapproved in a separate action in 2012. See 77 FR 33642 (June 7, 2012). EPA promulgated a Federal Implementation Plan (FIP) to address these requirements in 2017 and revised it in 2020. See 82 FR 48324 (October 17, 2017) and 85 FR 49170 (Aug.12, 2020) As such this action does not address BART for EGUs in Texas. </FTNT> On March 20, 2014, Texas submitted its five-year progress report as a SIP revision (2014 Plan) to satisfy the requirements of 40 CFR 51.308(g) and (h). The EPA is proposing to approve Texas's 2014 Plan. On July 20, 2021, Texas submitted a revision to its SIP to address regional haze for the second planning period (2021 Plan). Texas made this SIP submission to satisfy the requirements of the CAA's regional haze program pursuant to CAA sections 169A and 169B and 40 CFR 51.308. The EPA is proposing to approve the 2021 Plan. <HD SOURCE="HD1">II. Background and Regional Haze Rule Requirements</HD> In the 1977 CAA Amendments, Congress created a program for protecting visibility in the nation's mandatory Class I Federal areas, which include certain national parks and wilderness areas. <SU>2</SU> <FTREF/> The CAA establishes as a national goal the “prevention of any future, and the remedying of any existing, impairment of visibility in mandatory Class I Federal areas which impairment results from manmade air pollution.”  <SU>3</SU> <FTREF/> <FTNT> <SU>2</SU>  CAA section 169A. Areas statutorily designated as mandatory Class I Federal areas consist of national parks exceeding 6,000 acres, wilderness areas and national memorial parks exceeding 5,000 acres, and all international parks that were in existence on August 7, 1977. CAA section 162(a). There are 156 mandatory Class I areas. The list of areas to which the requirements of the visibility protection program apply is in 40 CFR part 81, subpart D. </FTNT> <FTNT> <SU>3</SU>  CAA section 169A. </FTNT> Regional haze is visibility impairment that is produced by a multitude of anthropogenic sources and activities which are located across a broad geographic area and that emit pollutants that impair visibility. 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> sulfur dioxide (SO <E T="52">2</E> ), nitrogen oxides (NO <E T="52">X</E> ), and, in some cases, volatile organic compounds (VOC) and ammonia (NH <E T="52">3</E> )). Fine particle precursors react in the atmosphere to form fine particulate matter (PM <E T="52">2.5</E> ), which impairs visibility by scattering and absorbing light. Visibility impairment reduces the perception of clarity and color, as well as visible distance. <SU>4</SU> <FTREF/> <FTNT> <SU>4</SU>  There are several ways to measure the amount of visibility impairment, <E T="03">i.e.,</E> haze. One such measurement is the deciview, which is the principal metric used by the RHR. Under many circumstances, a change in one deciview will be perceived by the human eye to be the same on both clear and hazy days. The deciview is unitless. It is proportional to the logarithm of the atmospheric extinction of light, which is the perceived dimming of light due to its being scattered and absorbed as it passes through the atmosphere. Atmospheric light extinction (b <SU>ext</SU> ) is a metric used for expressing visibility and is measured in inverse megameters (Mm <E T="51">−1</E> ). Light extinction can be simpler to use in calculations than deciviews, since it is not a logarithmic function. The formula for the deciview is 10 ln (b <SU>ext</SU> )/10 Mm−1). 40 CFR 51.301. </FTNT> To address regional haze visibility impairment, the 1999 RHR established an iterative planning process that requires both States in which Class I areas are located and states “the emissions from which may reasonably be anticipated to cause or contribute to any impairment of visibility” in a Class I area to periodically submit SIP revisions to address such impairment. CAA section 169A(b)(2);  <SU>5</SU> <FTREF/> see also 40 CFR 51.308(b) and (f) (establishing submission dates for iterative regional haze SIP revisions); 64 FR 35714, 35768 (July 1, 1999). <FTNT> <SU>5</SU>  The RHR expresses the statutory requirement for States to submit plans addressing out-of-State Class I areas by providing that States must address visibility impairment “in each mandatory Class I Federal area located outside the State that may be affected by emissions from within the State.” 40 CFR 51.308(d) and (f). </FTNT> <HD SOURCE="HD2">A. Regional Haze Rule Requirements for the First Planning Period</HD> Much of the focus in the first implementati ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 246k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━