{"abstract":"The Environmental Protection Agency (EPA) is taking final action to redesignate the nonattainment area in Muscatine County, Iowa to attainment for the 2010 1-hour sulfur dioxide (SO<INF>2</INF>) National Ambient Air Quality Standard (NAAQS). The EPA is also approving Iowa's maintenance plan for the 2010 1-hour SO<INF>2</INF> NAAQS for the Muscatine nonattainment area and approving modifications to source-specific permits in the Iowa State Implementation Plan (SIP). The EPA is taking this action in accordance with the requirements of the Clean Air Act (CAA).","action":"Final rule.","agencies":[{"raw_name":"ENVIRONMENTAL PROTECTION AGENCY","name":"Environmental Protection Agency","id":145,"url":"https://www.federalregister.gov/agencies/environmental-protection-agency","json_url":"https://www.federalregister.gov/api/v1/agencies/145","parent_id":null,"slug":"environmental-protection-agency"}],"body_html_url":"https://www.federalregister.gov/documents/full_text/html/2025/11/18/2025-20197.html","cfr_references":[{"chapter":null,"citation_url":null,"part":"52","title":40},{"chapter":null,"citation_url":null,"part":"81","title":40}],"citation":"90 FR 51554","comment_url":null,"comments_close_on":null,"correction_of":null,"corrections":[],"dates":"This final rule is effective on December 18, 2025.","disposition_notes":null,"docket_ids":["EPA-R07-OAR-2025-0818","FRL-12901-02-R7"],"dockets":[{"supporting_documents":[{"title":"File List IDNR Submitted Modeling Muscatine IA","document_id":"EPA-R07-OAR-2025-0818-0012"},{"title":"muscatine1hrSO2-maintenanceSIP.final_","document_id":"EPA-R07-OAR-2025-0818-0011"},{"title":"Muscatine IA 2010 SO2 Redesignation TSD","document_id":"EPA-R07-OAR-2025-0818-0010"},{"title":"GPC Excess Emission Reports Summary 02-24-2025","document_id":"EPA-R07-OAR-2025-0818-0009"},{"title":"GPC Excess Emission Reports Past 5 years","document_id":"EPA-R07-OAR-2025-0818-0008"},{"title":"Calcagni Memo","document_id":"EPA-R07-OAR-2025-0818-0007"},{"title":"Attachment3-Monsanto","document_id":"EPA-R07-OAR-2025-0818-0006"},{"title":"Attachment2-MPW","document_id":"EPA-R07-OAR-2025-0818-0005"},{"title":"Attachment1-GPC","document_id":"EPA-R07-OAR-2025-0818-0004"},{"title":"20211112-RedesignationTransmittalLetter","document_id":"EPA-R07-OAR-2025-0818-0003"}],"agency_name":"EPA","documents":[{"comment_count":0,"comment_start_date":"2025-11-18","updated_at":"2025-11-18T09:14:07.429-05:00","comment_url":"https://www.regulations.gov/commenton/EPA-R07-OAR-2025-0818-0013","allow_late_comments":false,"id":"EPA-R07-OAR-2025-0818-0013","comment_end_date":null,"regulations_dot_gov_open_for_comment":false}],"supporting_documents_count":11,"id":"EPA-R07-OAR-2025-0818","title":"Air Plan Approval; IA, Muscatine; 2010 1-Hour SO2 Maintenance Plan and Redesignation"}],"document_number":"2025-20197","effective_on":"2025-12-18","end_page":51559,"executive_order_notes":null,"executive_order_number":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2025/11/18/2025-20197.xml","html_url":"https://www.federalregister.gov/documents/2025/11/18/2025-20197/air-plan-approval-ia-muscatine-2010-1-hour-so2-maintenance-plan-and-redesignation","images":{},"images_metadata":{},"json_url":"https://www.federalregister.gov/api/v1/documents/2025-20197?publication_date=2025-11-18","mods_url":"https://www.govinfo.gov/metadata/granule/FR-2025-11-18/2025-20197/mods.xml","not_received_for_publication":null,"page_length":6,"page_views":{"count":132,"last_updated":"2026-06-08 20:15:03 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2025-11-18/pdf/2025-20197.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":"https://public-inspection.federalregister.gov/2025-20197.pdf?1763387139","publication_date":"2025-11-18","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2025/11/18/2025-20197.txt","regulation_id_number_info":{},"regulation_id_numbers":[],"regulations_dot_gov_info":{"supporting_documents":[{"title":"File List IDNR Submitted Modeling Muscatine IA","document_id":"EPA-R07-OAR-2025-0818-0012"},{"title":"muscatine1hrSO2-maintenanceSIP.final_","document_id":"EPA-R07-OAR-2025-0818-0011"},{"title":"Muscatine IA 2010 SO2 Redesignation TSD","document_id":"EPA-R07-OAR-2025-0818-0010"},{"title":"GPC Excess Emission Reports Summary 02-24-2025","document_id":"EPA-R07-OAR-2025-0818-0009"},{"title":"GPC Excess Emission Reports Past 5 years","document_id":"EPA-R07-OAR-2025-0818-0008"},{"title":"Calcagni Memo","document_id":"EPA-R07-OAR-2025-0818-0007"},{"title":"Attachment3-Monsanto","document_id":"EPA-R07-OAR-2025-0818-0006"},{"title":"Attachment2-MPW","document_id":"EPA-R07-OAR-2025-0818-0005"},{"title":"Attachment1-GPC","document_id":"EPA-R07-OAR-2025-0818-0004"},{"title":"20211112-RedesignationTransmittalLetter","document_id":"EPA-R07-OAR-2025-0818-0003"}],"comments_count":0,"agency_id":"EPA","comments_url":"https://www.regulations.gov/docketBrowser?rpp=50&so=DESC&sb=postedDate&po=0&dct=PS&D=EPA-R07-OAR-2025-0818","supporting_documents_count":11,"docket_id":"EPA-R07-OAR-2025-0818","document_id":"EPA-R07-OAR-2025-0818-0013","regulation_id_number":null,"title":"Air Plan Approval; IA, Muscatine; 2010 1-Hour SO2 Maintenance Plan and Redesignation","checked_regulationsdotgov_at":"2025-11-19T17:55:06Z"},"regulations_dot_gov_url":null,"significant":null,"signing_date":null,"start_page":51554,"subtype":null,"title":"Air Plan Approval; IA, Muscatine; 2010 1-Hour SO2 Maintenance Plan and Redesignation","toc_doc":"Iowa, Muscatine; 2010 1-Hour SO2 Maintenance Plan and Redesignation","toc_subject":"Air Quality State Implementation Plans; Approvals and Promulgations","topics":["Air pollution control","Environmental protection","Incorporation by reference","Intergovernmental relations","Reporting and recordkeeping requirements","Sulfur oxides"],"type":"Rule","volume":90}