Designation of Areas for Air Quality Planning Purposes; Redesignation Request and Associated Maintenance Plan for Whatcom County, WA 2010 SO2 Nonattainment Area

<RULE> ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Parts 52 and 81</CFR> <DEPDOC>[EPA-R10-OAR-2024-0371; FRL-12159-02-R10]</DEPDOC> <SUBJECT> Designation of Areas for Air Quality Planning Purposes; Redesignation Request and Associated Maintenance Plan for Whatcom County, WA 2010 SO <E T="0735">2</E> Nonattainment Area </SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Environmental Protection Agency (EPA). <HD SOURCE="HED">ACTION:</HD> Final rule. <SUM> <HD SOURCE="HED">SUMMARY:</HD> On July 25, 2024, the State of Washington (WA) submitted a request for the Environmental Protection Agency (EPA) to redesignate to attainment a portion of Whatcom County immediately surrounding the now permanently closed aluminum smelter, Intalco Aluminum LLC, which the EPA designated nonattainment for the 2010 1-hour primary sulfur dioxide (SO <E T="52">2</E> ) National Ambient Air Quality Standard (NAAQS). Washington also submitted a request for the EPA to approve a State Implementation Plan (SIP) revision containing a maintenance plan for the area. The EPA is taking the following final actions: we have determined that the Whatcom County (partial) SO <E T="52">2</E> nonattainment area (Whatcom County area or area) is attaining the 2010 1-hour primary SO <E T="52">2</E> NAAQS; we are approving Washington's plan for maintaining attainment of the 2010 1-hour primary SO <E T="52">2</E> NAAQS in the area; and we are redesignating the Whatcom County area to attainment for the 2010 1-hour primary SO <E T="52">2</E> NAAQS. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This final rule is effective January 16, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> The EPA has established a docket for this action under Docket ID No. EPA-R10-OAR-2024-0371. 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">I. Background</HD> On September 27, 2024 (89 FR 79195), The EPA proposed to take the following four separate but related actions: (1) determine that the Whatcom County area is attaining the 2010 1-hour SO <E T="52">2</E> NAAQS; (2) approve Washington's plan for maintaining the 2010 1-hour SO <E T="52">2</E> NAAQS (maintenance plan), including proposed approval of a “reproducible approach” to representing the air quality of the affected area; (3) redesignate the Whatcom County area to attainment for the 2010 1-hour SO <E T="52">2</E> NAAQS; and (4) determine that the Whatcom County area has clean monitoring data. The public comment period for the proposed actions closed on October 28, 2024. We received two anonymous comments, document EPA-R10-OAR-2024-0371-0014 (comment #1) and EPA-R10-OAR-2024-0371-0015 (comment #2). Both comments expressed support for the EPA's approval of Washington's redesignation request and maintenance plan. However, comment #1 and comment #2 raised concerns about Washington's ability to verify continued attainment. In addition, comment #2 suggested the contingency measures contain more specificity and that Washington should include a public accessibility plan in its Maintenance Plan. The full text of the comments may be found in the docket for this action, and we have responded to the relevant comments in section II. of this preamble. Under the Clean Air Act (CAA), the Administrator is required to approve a SIP submission that complies with the provisions of the CAA and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, the EPA's role is to approve State choices, provided that they meet the criteria of the CAA. <HD SOURCE="HD1">II. EPA Responses to Comments Received</HD> <HD SOURCE="HD2">A. Monitoring Network and Verification of Continued Attainment</HD> <E T="03">Comment:</E> The EPA's proposed rulemaking provided a synopsis of Washington's strategy for verification of continued attainment in the area as part of the State's maintenance plan. <SU>1</SU> <FTREF/> A more detailed explanation of Washington's “reproducible approach” to representing air quality, submitted to allow future monitor system modification under 40 CFR 58.14(c)(3), was provided in the maintenance plan itself. <SU>2</SU> <FTREF/> With respect to this issue, comment #1 contains the statement, “although this has well solidified evidence, it is necessary to continue monitoring the nonattainment and attainment areas of Whatcom County to ensure the air quality stays in line with the EPA's NAAQS. If the EPA did approve the request from Washington State it would further confirm the EPA's dedication to implementing their own policies.” Comment #2 states, “while the plan allows for flexibility in adjusting SO <E T="52">2</E> monitoring sites, it is crucial to consider that SO <E T="52">2</E> impacts often disproportionately affect vulnerable communities. Could the EPA establish clearer criteria or a more rigorous review process before relocating or decommissioning monitors? This would ensure that communities previously affected by emissions from the Intalco facility continue to have adequate air quality protections, even in the absence of a large point source.” <FTNT> <SU>1</SU>  See 89 FR 79195 (September 27, 2024) at pages 79200-79202. </FTNT> <FTNT> <SU>2</SU>  See Chapter 6, Verification of Attainment, Control Measures, and Maintenance Demonstration, at pages 35-43. </FTNT> <E T="03">Response:</E> We agree that Washington's maintenance plan should contain provisions for monitoring air quality in the area and verifying continued attainment. As discussed in the preamble to the proposed rulemaking, the maintenance plan contains these provisions and otherwise meets the maintenance plan requirements in CAA section 175A and the EPA's associated guidance. <SU>3</SU> <FTREF/> Neither comment directly addresses the EPA's evaluation of these provisions in the preamble to the proposed rulemaking nor provides a basis for disapproving Washington's maintenance plan. To the extent the comments imply that the maintenance plan is inadequate to monitor and verify continued attainment or lacks specificity in this regard, we disagree. The following discussion summarizes Washington's approach to monitoring air quality in the area post-redesignation and verifying continued attainment. <FTNT> <SU>3</SU>  42 U.S.C. 7505a and the September 4, 1992, Memorandum from John Calcagni titled “Procedures for Processing Requests to Redesignate Areas to Attainment.” </FTNT> In the EPA's December 2020 technical support document for the nonattainment designation, we determined the region of violation was most likely due to plume downwash at the Intalco facility during certain wind conditions, that the modeled area of violation did not extend far from the Intalco facility fence line, that the gradient of concentration near the areas of violation was steep, quickly dropping with distance from the Intalco facility fence line, and that other nearby industrial facilities did not sufficiently contribute to violations of the 1-hour primary SO <E T="52">2</E> NAAQS to warrant inclusion in the nonattainment area boundary. <SU>4</SU> <FTREF/> In our final nonattainment boundary determination, we concurred with the Washington Department of Ecology (Ecology) and Northwest Clean Air Agency (NWCAA) that the boundary should be drawn to encompass the cause of the SO <E T="52">2</E> violations, the Intalco facility. <FTNT> <SU>4</SU>  See 201_Appendix A Whatcom County SO <E T="52">2</E> Area Designation.pdf, included in the docket for this action. </FTNT> With the permanent closure of the Intalco facility, Washington's comprehensive emissions inventory, prepared as part of the maintenance plan, shows no remaining significant sources of SO <E T="52">2</E> , including mobile or area source emissions. <SU>5</SU> <FTREF/> Therefore, in the absence of any current SO <E T="52">2</E> emission sources, Washington's monitoring network and verification of continued attainment strategy focused on potential future emission sources that may be located within the area. <SU>6</SU> <FTREF/> <FTNT> <SU>5</SU>  See Chapter 5, Emissions Inventory, at pages 25-34. </FTNT> <FTNT> <SU>6</SU>  See Chapter 6, Verification of Attainment, Control Measures, and Maintenance Demonstration, at pages 35-43. </FTNT> As described in our proposed rulemaking and the State's maintenance plan, the new source review (NSR) program ensures that any single facility applying for a permit to locate within the area complies with the NAAQS and other regulatory requirements. <SU>7</SU> <FTREF/> In addition, Washington's maintenance plan included a stepwise process for assessing the cumulative impacts of new sources constructed in the area and triggering deployment of SO <E T="52">2</E> monitors. This process ensures that cumulative impacts remain below the NAAQS should multiple facilities move to the area. Under the maintenance plan verificat ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 32k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━