Approval and Promulgation of Air Quality Implementation Plans; Nevada; Regional Haze State Implementation Plan for the Second Implementation Period

<RULE> ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Part 52</CFR> <DEPDOC>[EPA-R09-OAR-2025-0101; FRL-12600-02-R9]</DEPDOC> <SUBJECT>Approval and Promulgation of Air Quality Implementation Plans; Nevada; Regional Haze State Implementation Plan for the Second Implementation Period</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 portions of the regional haze state implementation plan (SIP) revisions submitted by the Nevada Division of Environmental Protection (NDEP) on August 12, 2022 (“2022 Nevada Regional Haze Plan”) and on May 28, 2025 (“2025 SIP Supplement”), as satisfying applicable requirements under the Clean Air Act (CAA) and the EPA's Regional Haze Rule (RHR) for the program's second implementation period. These revisions address the requirement that states must periodically revise their long-term strategies for making reasonable progress towards the national goal of preventing any future, and remedying any existing, anthropogenic impairment of visibility, including regional haze, in mandatory Class I Federal areas. The revisions also address other applicable requirements for the second implementation period of the regional haze program. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This final rule is effective on March 9, 2026. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> The EPA has established a docket for this action under Docket ID No. EPA-R09-OAR-2025-0101. 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> Emily Millar, 880 Front Street, San Diego, CA 92101, Geographic Strategies and Modeling Section (ARD-2-2), Planning & Analysis Branch, EPA Region IX, telephone number: (213) 244-1882, email address: <E T="03">millar.emily@epa.gov.</E> </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> Throughout this document, “we,” “us,” and “our” refer to the EPA. <HD SOURCE="HD1">Table of Contents</HD> <EXTRACT> <FP SOURCE="FP-2">I. Background</FP> <FP SOURCE="FP-2">II. Public Comments and EPA Responses</FP> <FP SOURCE="FP-2">III. Final Action</FP> <FP SOURCE="FP-2">IV. Incorporation by Reference</FP> <FP SOURCE="FP-2">V. Statutory and Executive Order Reviews</FP> </EXTRACT> <HD SOURCE="HD1">I. Background</HD> On August 12, 2022, NDEP submitted the 2022 Nevada Regional Haze Plan, titled “Nevada Regional Haze State Implementation Plan for the Second Planning Period” as a revision to the Nevada SIP to address regional haze for the second implementation period. NDEP 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 found this submission complete on August 16, 2022. On July 27, 2023, NDEP withdrew the reasonable progress determinations for Tracy Generating Station's Piñon Pine Unit (also known variously as Tracy Unit 4 and Tracy Unit 7) and North Valmy Generating Station's Unit 1 and Unit 2. On May 28, 2025, NDEP submitted the 2025 SIP Supplement, titled “Nevada Regional Haze Revision to the State Implementation Plan for the Second Planning Period,” which includes revised reasonable progress determinations for those two sources. The 2025 Supplement also includes updated permits for three sources, replacing those submitted as part of the 2022 Nevada Regional Haze Plan. On October 23, 2025, the EPA proposed to approve the 2022 Nevada Regional Haze Plan (excluding the portions withdrawn on July 27, 2023) and appendix A (“Air Quality Permits Incorporated by Reference”) of the 2025 Supplement (collectively “the Plan”) into the Nevada SIP. <SU>1</SU> <FTREF/> The October 23, 2025 proposal provided background on the requirements of the CAA and RHR, summarized the Plan, and explained the rationale for our proposed action. That background and rationale will not be restated in full here. <FTNT> <SU>1</SU>  90 FR 48481. </FTNT> <HD SOURCE="HD1">II. Public Comments and EPA Responses</HD> The EPA's October 23, 2025 proposal provided a 30-day public comment period that ended on November 24, 2025. The EPA received nine comments during the comment period: three anonymous comments; one comment from a private individual; a comment from Mid-Atlantic/Northeast Visibility Union (MANEVU); a comment from Citizens Rulemaking Alliance; a comment from Idaho Power Company; a comment from NV Energy; and a joint comment letter signed by the National Parks Conservation Association (NPCA), Sierra Club, Center for Biological Diversity, and Coalition to Protect America's National Parks. After reviewing the anonymous comments and the comment from the private individual, the EPA has determined that they fail to raise issues germane to the approval of the Plan, which is based on the criteria set forth in the CAA, the RHR and relevant policy documents. Therefore, we have determined that these comments do not necessitate a response, and the EPA will not provide specific responses to these comments. The comments from Idaho Power Company and NV Energy supported the EPA's proposed action. The EPA acknowledges these supportive comments, which are included in the docket for this action. We respond to the issues raised in the three remaining comment letters received on our proposed rulemaking in this document and the associated response to comments (RTC) Document, which is included in the docket for this rulemaking. We briefly address in this section the following topics that were raised by commenters: (1) whether the EPA's new policy is consistent with the CAA and RHR; (2) whether the EPA sufficiently justified its basis for the new policy; (3) whether the action is nationally applicable or based on a determination of nationwide scope and effect; (4) whether the action departs from national policy without complying with the EPA's consistency regulations at 40 CFR part 56; and (5) whether the Plan meets the applicable statutory and regulatory requirements in accordance with the new policy. As stated in the proposal, it is now the EPA's policy that, where visibility conditions for a Class I Federal area impacted by a state are below the Uniform Rate of Progress (URP) and the state has considered the four statutory factors, the state will have presumptively demonstrated reasonable progress for the second planning period for that area. <SU>2</SU> <FTREF/> As detailed at length in the RTC Document section III., the EPA's new policy is consistent with the CAA. Pursuant to CAA 169A(a)(4), Congress explicitly delegated to the EPA the authority to promulgate regulations regarding reasonable progress towards meeting the national goal. As some commenters note, to determine the measures necessary to make reasonable progress towards the national visibility goal under 169A(a)(1), Congress mandated “tak[ing] into consideration the cost of compliance, the time necessary for compliance, and the energy and nonair quality environmental impacts of compliance, and the remaining useful life of any existing source subject to such requirement.”  <SU>3</SU> <FTREF/> <FTNT> <SU>2</SU>  90 FR 48481, 48496 (citing, <E T="03">e.g.,</E> 90 FR 29737, 29738 (July 7, 2025); 90 FR 20425, 20434 (May 14, 2025)). </FTNT> <FTNT> <SU>3</SU>  CAA 169A(g)(1). </FTNT> The EPA emphasizes that just because a Class I area is below the URP does not mean that a state is relieved of its obligations under the CAA and the RHR to make reasonable progress. In other words, the URP is not a “safe harbor,” as that phrase has sometimes been used, because the EPA still must review a state's determination whether additional control measures are necessary to make reasonable progress, determine whether the state submitted those measures for incorporation into the SIP, and evaluate whether the measures are consistent with other provisions in the CAA. Regarding the basis for the new policy, under <E T="03">FCC</E> v. <E T="03">Fox Television,</E> 556 U.S. 502 (2009), an agency's change in policy is permissible if the agency acknowledges the change, believes it to be better, and “show[s] that there are good reasons for the new policy.”  <SU>4</SU> <FTREF/> In section IV.E.7. of our proposal for this rulemaking, we referred to previous actions, in which we stated our reasons for implementing this new policy. <SU>5</SU> <FTREF/> <FTNT> <SU>4</SU>  556 U.S. 502, 515. </FTNT> <FTNT> <SU>5</SU>  90 FR 48481, 48496 (citing <E T="03">e.g.,</E> 90 FR 29737, 29738 (July 7, 2025); 90 FR 20425, 20434 (May 14, 2025)). </FTNT> The decision in <E T="03">FCC</E> v. <E T="03">Fox</E> turned primarily on whether the FCC's change in policy would lead to the FCC “arbitrarily punishing parties without notice of the potential consequences of their action.”  <SU>6</SU> <FTREF/> In this instance, the changed policy is prospective, which addresses the primary concern in <E T="03">FCC</E> v. <E T="03">Fox.</E> Additionally, the new policy “aligns with the purpose of the statute and RHR, which is achieving `reasonable' progress, not maximal progress, toward Congress' natural visibility goal.”  <SU ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 30k characters. 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