Air Plan Approval; Washington; Regional Haze State Implementation Plan for the Second Implementation Period

<RULE> ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Part 52</CFR> <DEPDOC>[EPA-R10-OAR-2024-0541; FRL-12449-02-R10]</DEPDOC> <SUBJECT>Air Plan Approval; Washington; 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 the regional haze State implementation plan (SIP) revision, submitted by Washington on January 28, 2022, to address applicable requirements under the Clean Air Act (CAA) and the EPA's Regional Haze Rule (RHR) for the regional haze program's second implementation period. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This final rule is effective October 27, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> The EPA has established a docket for this action under Docket ID No. EPA-R10-OAR-2024-0541. 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 or other information the disclosure of which 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 at <E T="03">https://www.regulations.gov,</E> or please contact the person listed in the <E T="02">FOR FURTHER INFORMATION CONTACT</E> section for additional availability information. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Jeff Hunt, EPA Region 10, 1200 Sixth Avenue, Suite 155, Seattle, WA 98101, at (206) 553-0256 or <E T="03">hunt.jeff@epa.gov.</E> </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> Throughout this document, wherever “we” or “our” is used, it means the EPA. <HD SOURCE="HD1">Table of Contents</HD> <EXTRACT> <FP SOURCE="FP-2">I. What is being addressed in this document?</FP> <FP SOURCE="FP-2">II. Summary of the Proposed Action and the EPA's Reasons for This Final Action</FP> <FP SOURCE="FP-2">III. Public Comments and EPA Responses</FP> <FP SOURCE="FP-2">IV. Final Action</FP> <FP SOURCE="FP-2">V. Incorporation by Reference</FP> <FP SOURCE="FP-2">VI. Statutory and Executive Order Reviews</FP> </EXTRACT> <HD SOURCE="HD1">I. What is being addressed in this document?</HD> The EPA is approving a SIP revision submitted by the State of Washington to the EPA on January 28, 2022, addressing the Regional Haze Rule (RHR) requirements for the regional haze program's second implementation period. As required by section 169A of the CAA, the RHR calls for state and Federal agencies to work together to improve visibility in 156 national parks and wilderness areas. The RHR requires the states, in coordination with the EPA, the Federal Land Managers (FLMs), 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 (Class I areas). Visibility impairing pollutants include fine and coarse particulate matter ( <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, oxides of nitrogen, and, in some cases, volatile organic compounds and ammonia). As discussed in further detail in our proposed action published on July 24, 2025 (90 FR 34792), in this document, and in the accompanying Response to Comments (RTC) document, the EPA finds that Washington submitted a SIP revision that meets all RHR requirements for the second implementation period. Washington's SIP revision, the proposed action, and the accompanying RTC document may be found in the docket for this action. <HD SOURCE="HD1">II. Summary of the Proposed Action and the EPA's Reasons for This Final Action</HD> <HD SOURCE="HD2">A. Summary of the Proposed Action</HD> On January 28, 2022, Washington submitted a SIP revision to address its regional haze obligations for the second implementation period (2018-2028). Washington made this revision to satisfy the requirements of the CAA's regional haze program pursuant to CAA sections 169A and 169B and 40 Code of Federal Regulations (CFR) 51.308. On July 24, 2025, the EPA proposed to approve Washington's 2022 SIP revision (90 FR 34792). Specifically, the EPA proposed to approve Washington's 2022 SIP revision as satisfying the requirements of 40 CFR 51.308(f)(1): calculations of baseline, current, and natural visibility conditions, progress to date, and the uniform rate of progress; 40 CFR 51.308(f)(2): long-term strategy; 40 CFR 51.308(f)(3): reasonable progress goals; 40 CFR 51.308(f)(4): reasonably attributable visibility impairment; 40 CFR 51.308(f)(5) and 40 CFR 51.308(g): progress report requirements; 40 CFR 51.308(f)(6): monitoring strategy and other implementation plan requirements; and 40 CFR 51.308(i): FLM consultation. Our public comment period closed on August 25, 2025. We received 5 comments, the full text of which may be found in the docket for this action. Our July 2025 proposed action provided background on the requirements of the CAA and RHR, a summary of Washington's regional haze SIP revision and related EPA actions, and the EPA's rationale for its proposed action. That background and rationale will not be restated here. <HD SOURCE="HD2">B. Reasons for This Final Action</HD> In this final action, the EPA is affirming that it is now the Agency's policy that, where visibility conditions for a Class I 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 implementation period for that Class I area. The EPA acknowledges that this final action reflects a change in policy as to how the URP should be used in the evaluation of regional haze second implementation period SIP revisions but believes that this policy better aligns with the purpose of the statute and RHR: achieving “reasonable” progress towards natural visibility. As described in the final rule approving West Virginia's regional haze plan, the EPA has discretion and authority to change its policy. <SU>1</SU> <FTREF/> In <E T="03">FCC</E> v. <E T="03">Fox Television Stations, Inc.,</E> the U.S. Supreme Court plainly stated that an agency is free to change a prior policy and “need not demonstrate . . . that the reasons for the new policy are better than the reasons for the old one; it suffices that the new policy is permissible under the statute, that there are good reasons for it, and that the agency believes it to be better.” 566 U.S. 502, 515 (2009) (referencing Motor <E T="03">Vehicle Mfrs. Ass'n of United States, Inc.</E> v. <E T="03">State Farm Mut. Auto. Ins. Co.,</E> 463 U.S. 29 (1983)). <E T="03">See also Perez</E> v. <E T="03">Mortgage Bankers Assn.,</E> 135 S. Ct. 1199 (2015). <FTNT> <SU>1</SU>  90 FR 29737 (August 6, 2025). </FTNT> The Class I areas impacted by emissions from Washington are all below the 2028 URP, and Washington's SIP revision demonstrated that the state took into consideration the four reasonable progress factors listed in CAA section 169A(g)(1)  <SU>2</SU> <FTREF/> with respect to an adequate number of emissions sources. Thus, the EPA has determined that Washington's SIP revision is fully approvable under the Agency's new policy. Indeed, we think this policy better aligns with the statutory goal because it recognizes the considerable improvements in visibility impairment that have been made by a wide variety of state and Federal programs in recent decades. <FTNT> <SU>2</SU>   The four statutory factors required to be taken into consideration in determining reasonable progress are: the costs of compliance, the time necessary for compliance, and the energy and non-air quality environmental impacts of compliance, and the remaining useful life of any existing source subject to such requirements. CAA section 169(g)(1). </FTNT> In developing the regulations required by CAA section 169A(b), the EPA established the concept of the URP for each Class I area. The URP is determined by drawing a straight line from the measured 2000-2004 baseline conditions (in deciviews) for the 20% most impaired days at each Class I area to the estimated natural conditions (in deciviews) for the 20% most impaired days in 2064. From this calculation, a URP value can be calculated for each year between 2004 and 2064. The EPA developed the URP to address the diverse concerns of Eastern and Western states and account for the varying levels of visibility impairment in Class I areas around the country while ensuring an equitable approach nationwide. For each Class I area, states must calculate the URP for the end of each implementation period ( <E T="03">e.g.,</E> in 2028 for the second implementation period). <SU>3</SU> <FTREF/> 40 CFR 51.308(f)(1)(vi)(A). States may also adjust the URP to account for impacts from anthropogenic sources outside the United States and/or impacts from certain wildland prescribed fires. 40 CFR 51.308(f)(1)(vi)(B). Then, for each Class I area, states must compare the reasonable progress goal (RPG) for the 20% most impaired days to the URP for the end of the implementation period. If the RPG is above the URP, then an additional “robust demonstration” requirement is triggered for each state that contributes to that Class I area. 40 CFR 51.308(f)(3)(ii)(B). <FTNT> <SU>3</SU>  We note that RPGs are a regulatory construct that we developed to address the statutory mandate in CAA section 169B(e)(1), which required our regulations to include “criteria for m ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 26k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━