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

ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Part 52</CFR> <DEPDOC>[EPA-R10-OAR-2024-0541; FRL-12449-01-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> Proposed rule. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The Environmental Protection Agency (EPA) is proposing to approve 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. The EPA is proposing this action pursuant to the CAA. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> Written comments must be received on or before August 25, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Submit your comments, identified by Docket ID No. EPA-R10-OAR-2024-0541 at <E T="03">www.regulations.gov.</E> For comments submitted at <E T="03">Regulations.gov</E> , follow the online instructions for submitting comments. Once submitted, comments may not be edited or removed from <E T="03">regulations.gov.</E> For either manner of submission, the EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be confidential business information or other information the disclosure of which 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 the person identified in the <E T="02">FOR FURTHER INFORMATION CONTACT</E> section. For the full EPA public comment policy, information about confidential business information or multimedia submissions, and general guidance on making effective comments, please visit <E T="03">https://www.epa.gov/dockets/commenting-epa-dockets.</E> <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, the use of “we” and “our” means the EPA. <HD SOURCE="HD1">Table of Contents</HD> <EXTRACT> <FP SOURCE="FP-2">I. What action is the EPA proposing?</FP> <FP SOURCE="FP-2">II. Background and Requirements for Regional Haze Plans</FP> <FP SOURCE="FP-2">III. Requirements for Regional Haze Plans for the Second Implementation Period</FP> <FP SOURCE="FP-2">IV. The EPA's Evaluation of the Washington Regional Haze Plan for the Second Implementation Period</FP> <FP SOURCE="FP-2">V. Proposed Action</FP> <FP SOURCE="FP-2">VI. Incorporation by Reference</FP> <FP SOURCE="FP-2">VII. Statutory and Executive Order Reviews</FP> </EXTRACT> <HD SOURCE="HD1">I. What action is the EPA proposing?</HD> The EPA is proposing to approve the regional haze SIP revision submitted by the Washington Department of Ecology (Ecology) on January 28, 2022, under the CAA and the EPA's Regional Haze Rule for the program's second implementation period. Washington's SIP submission addresses 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 SIP submission also addresses other applicable requirements for the second implementation period of the regional haze program. The EPA is taking this action pursuant to CAA sections 110 and 169A. <HD SOURCE="HD1">II. Background and Requirements for Regional Haze Plans</HD> A detailed history and background of the regional haze program is provided in multiple prior EPA proposal actions. <SU>1</SU> <FTREF/> For additional background on the 2017 Regional Haze Rule (RHR) revisions, please refer to Section III of this publication. Overview of Visibility Protection Statutory Authority, Regulation, and Implementation of “Protection of Visibility: Amendments to Requirements for State Plans” of the 2017 RHR. <SU>2</SU> <FTREF/> The following is an abbreviated history and background of the regional haze program and 2017 RHR as it applies to the current action. <FTNT> <SU>1</SU>   <E T="03">See</E> 90 FR 13516 (March 24, 2025). </FTNT> <FTNT> <SU>2</SU>   <E T="03">See</E> 82 FR 3078 (January 10, 2017, located at <E T="03">https://www.federalregister.gov/documents/2017/01/10/2017-00268/protection-of-visibility-amendments-to-requirements-for-State-plans#h-16).</E> </FTNT> <HD SOURCE="HD2">A. Regional Haze</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. CAA 169A. 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.” CAA 169A(a)(1). In CAA section 169A(a)(1), Congress established the national goal of preventing any future and remedying any existing impairment of visibility in mandatory Class I Federal areas that results from manmade (anthropogenic) air pollution. The core component of a regional haze SIP submission for the second planning period is a strategy that addresses regional haze in each Class I area within the State's borders and each Class I area outside the State that may be affected by emissions originating from within the State, CAA section 169A(b)(2)(B), 40 CFR 51.308(f)(2), and makes “reasonable progress” toward the national goal based on consideration of the four statutory factors in CAA section 169A(g)(1)—the costs of compliance, the time necessary for compliance, the energy and non-air quality environmental impacts of compliance, and the remaining useful life of any potentially affected sources. <SU>3</SU> <FTREF/> <FTNT> <SU>3</SU>  CAA section 169A(g)(1); 40 CFR 51.308(f)(2)(i). </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> ). 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 169A(b)(2); see also 40 CFR 51.308(b), (f) (establishing submission dates for iterative regional haze SIP revisions); (64 FR 35714, July 1, 1999, at page 35768). On January 10, 2017, the EPA promulgated revisions to the RHR, (82 FR 3078, January 10, 2017), that apply for the second and subsequent implementation periods. The reasonable progress requirements as revised in the 2017 rulemaking (referred to here as the 2017 RHR Revisions) are codified at 40 CFR 51.308(f). <HD SOURCE="HD2">B. The Western Regional Air Partnership</HD> The Western Regional Air Partnership (WRAP)  <SU>5</SU> <FTREF/> is one of five regional air quality planning organizations across the United States. <SU>6</SU> <FTREF/> The WRAP functions as a voluntary partnership of State, Tribal, Federal, and Local air agencies whose purpose is to understand current and evolving air quality issues in the west. There are 15 member States, including Washington, and 28 Tribal and 30 Local air agency members. <SU>7</SU> <FTREF/> Federal partners include the EPA, National Park Service, U.S. Fish and Wildlife Service, Forest Service, and Bureau of Land Management. <FTNT> <SU>5</SU>  The WRAP website may be found at <E T="03">https://www.wrapair2.org.</E> </FTNT> <FTNT> <SU>6</SU>   <E T="03">See https:// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 145k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━