Air Plan Approval; Illinois; Alton Township 2010 Sulfur Dioxide Redesignation and Maintenance Plan

ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Parts 52 and 81</CFR> <DEPDOC>[EPA-R05-OAR-2023-0498; FRL-12265-01-R5]</DEPDOC> <SUBJECT>Air Plan Approval; Illinois; Alton Township 2010 Sulfur Dioxide Redesignation and Maintenance Plan</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 redesignate the Alton Township nonattainment area in Madison County, Illinois to attainment for the 2010 sulfur dioxide (SO <E T="52">2</E> ) National Ambient Air Quality Standard (NAAQS). EPA is also proposing to approve Illinois' maintenance plan for the area. Illinois submitted the request for approval on October 2, 2023. Additionally, EPA is proposing to determine the Alton Township area attained the 2010 SO <E T="52">2</E> NAAQS by the September 12, 2021, attainment date, fulfilling EPA's obligation under the Clean Air Act (CAA) to determine whether the area attained the relevant NAAQS standard within six months of the attainment date. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> Comments must be received on or before November 7, 2024. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Submit your comments, identified by Docket ID No. EPA-R05-OAR-2023-0498 at <E T="03">https://www.regulations.gov,</E> or via email to <E T="03">arra.sarah@epa.gov.</E> For comments submitted at <E T="03">Regulations.gov,</E> follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from the docket. EPA may publish any comment received to its public docket. Do not submit to EPA's docket at <E T="03">https://www.regulations.gov</E> any information you consider to be Confidential Business Information (CBI), Proprietary Business Information (PBI), 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. 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 CBI, PBI, 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> Cecilia Magos, Air and Radiation Division (AR18J), Environmental Protection Agency, Region 5, 77 West Jackson Boulevard, Chicago, Illinois 60604, (312) 886-7336, <E T="03">magos.cecilia@epa.gov.</E> The EPA Region 5 office is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding Federal holidays. </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> Throughout this document whenever “we,” “us,” or “our” is used, we mean EPA. <HD SOURCE="HD1">I. Background and Redesignation Requirements</HD> On June 22, 2010 (75 FR 35520), EPA revised the primary SO <E T="52">2</E> NAAQS, establishing a new health-based 1-hour standard of 75 parts per billion (ppb). EPA promulgated designations for this standard in four rounds. On September 18, 2015, Illinois submitted its recommendations to EPA to designate certain areas of the State as part of the Round 2 designations. Illinois recommended a portion of southern Alton Township in Madison County be designated as nonattainment for the 2010 SO <E T="52">2</E> NAAQS. EPA concurred with Illinois' analysis and published a final action designating the area as nonattainment for the 2010 SO <E T="52">2</E> NAAQS effective September 12, 2016 (81 FR 45039). Illinois submitted an attainment plan for the Alton Township nonattainment area on December 3, 2018. Under section 192(a) of the CAA, these plans are required to demonstrate that areas will attain the NAAQS as expeditiously as practicable, but no later than five years from the effective date of designation. The plan included modeling from emissions associated with the Alton Steel Inc. (Alton Steel) facility in Alton, Illinois, and emissions from the Ameren Missouri-Sioux Energy Center (Ameren-Sioux) power plant in Missouri, located about 13 kilometers west-northwest of the nonattainment area. The modeled emissions showed the nonattainment status of the area was mainly attributed to these two SO <E T="52">2</E> sources. Unlike the Round 2 designations modeling, the Alton Township attainment demonstration did not include the Wood River Power Station among the sources modeled due to the retirement of the facility in June 2016 and its demolition in February 2021. On March 14, 2019, after Illinois' submission of the attainment plan, the Illinois Environmental Protection Agency issued Construction Permit #18020009 for the Alton Steel facility to operate a new ladle metallurgy facility (LMF) stack, removing the downfacing vents that were contributing to modeled nonattainment at the facility. EPA included additional dispersion modeling to supplement Illinois' attainment demonstration to demonstrate that the emission limits required by the Illinois SIP and submitted for EPA approval provide for modeled concentrations meeting the 2010 SO <E T="52">2</E> NAAQS. EPA approved Illinois' attainment plan revision on February 21, 2023 (88 FR 10464). Additionally, under section 179(c)(1) of the CAA, EPA is required to determine whether a nonattainment area attained a standard by the applicable attainment date based on the area's air quality as of the attainment date. EPA is to issue this determination within six months of the attainment date. Thus, EPA had a mandatory duty under CAA section 179(c) to determine by March 12, 2022, whether the Alton Township area attained by September 12, 2021. As an additional action, EPA is proposing to determine the Alton Township area did attain the 2010 SO <E T="52">2</E> NAAQS by the attainment date of September 12, 2021. On October 2, 2023, Illinois submitted a redesignation request and maintenance plan for the Alton Township nonattainment area for the 2010 SO <E T="52">2</E> NAAQS. Additionally, on March 31, 2022, Missouri adopted into its SIP a Consent Agreement between the Missouri Department of Natural Resources' Air Pollution Control Program and Ameren-Sioux, APCP-2021-018. EPA approved the revision to incorporate the Ameren-Sioux Consent Agreement on November 16, 2022 (87 FR 68634), establishing an enforceable SO <E T="52">2</E> emissions limit for two coal-fired boilers at the facility. <E T="03">See</E> Appendix B of the State's submittal included in the public docket of this action—Ameren-Sioux Consent Agreement. The submitted redesignation request and maintenance plan includes the Construction Permit issued to Alton Steel and the Consent Agreement issued to Ameren-Sioux approved into the Missouri SIP (87 FR 68634, November 16, 2022) with accepted SO <E T="52">2</E> emissions limits. While the Ameren-Sioux facility is not in the Alton Township nonattainment area, Illinois included this facility in their modeling due to its close proximity to the nonattainment area and high SO <E T="52">2</E> emissions, using information provided by the Missouri Department of Natural Resources. EPA's supplemental modeling with the updated limit of 7,342 pounds per hour (lbs/hr) averaged over a 24-hour block period for the Ameren-Sioux facility outlined in the Consent Agreement, provided for attainment of the 2010 SO <E T="52">2</E> NAAQS, and thus is included in Illinois' submittal. Under section 107(d)(3)(E) of the CAA, EPA may not promulgate a redesignation of a nonattainment area (or portion thereof) unless: 1. EPA has determined that the area has attained the NAAQS; 2. EPA has fully approved the applicable implementation plan for the area under section 110(k) of the CAA; 3. EPA has determined that improvement in air quality is due to permanent and enforceable reductions in emissions resulting from implementation of the applicable implementation plan and applicable Federal air pollution control regulations and other permanent and enforceable reductions; 4. EPA has fully approved a maintenance plan for the area under section 175A of the CAA; and 5. The State containing such area has met all requirements applicable to the area under section 110 of the CAA and part D. <HD SOURCE="HD1">II. Evaluation of Illinois' Redesignation Request and Maintenance Plan</HD> On October 2, 2023, Illinois submitted a redesignation request for the Alton Township 2010 SO <E T="52">2</E> nonattainment area to attainment and a SIP revision containing a maintenance plan for the area. EPA's evaluation of Illinois' redesignation request and maintenance plan was based on consideration of the five redesignation criteria provided under CAA section 107(d)(3)(E). <HD SOURCE="HD2"> Criteria (1)—The Alton Township SO <E T="54">2</E> Nonattainment Area Has Attained the 2010 SO <E T="54">2</E> NAAQS </HD> In accordance with CAA section 107(d)(3)(E)(i), for redesignation of a nonattainment area to attainment, the CAA requires EPA to determine that the area has attained the applicable NAAQS. An area is attaining the 2010 SO <E T="52">2</E> NAAQS at an ambient air quality monitoring site, in accordance with 40 CFR 50.17 and appendix T of part 50, when the three-year average of the annual (99th percentile) of the daily maximum 1-hour average concentrations is less than or equal to 75 ppb. As stated in EPA's April 23, 2014, “Guidance for 1-Hour SO <E T="52">2</E> Nonattainment Area SIP Submissions” (“April 2014 SO ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 54k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━