{"abstract":"The U.S. Environmental Protection Agency (EPA) is proposing revisions to the Federal Implementation Plan (FIP) addressing regional haze in the State of Wyoming. The EPA is proposing revisions to the FIP's nitrogen oxides (NO<INF>X</INF>) best available retrofit technology (BART) requirements for the PacifiCorp Dave Johnston Power Plant Unit 3. In response to PacifiCorp's letter no longer consenting to closure of Dave Johnston Unit 3, the EPA is proposing to withdraw the NO<INF>X</INF> BART determination containing the closure requirement. Additionally, in response to a request from PacifiCorp, and in light of new information that was not available at the time the EPA originally promulgated the FIP in 2014, the Agency is also proposing to revise the other NO<INF>X</INF> BART determination for Dave Johnston Unit 3.","action":"Proposed 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/2026/06/08/2026-11436.html","cfr_references":[{"chapter":null,"citation_url":null,"part":"52","title":40}],"citation":"91 FR 34589","comment_url":"http://www.regulations.gov/commenton/EPA-R08-OAR-2026-1651-0003","comments_close_on":"2026-07-23","correction_of":null,"corrections":[],"dates":"Comments: Written comments must be received on or before July 23, 2026 unless a public hearing is held. If a public hearing is held, comments on this notice of proposed rulemaking must be received on or before date 30 days after date of public hearing.","disposition_notes":null,"docket_ids":["EPA-R08-OAR-2026-1651","FRL-13299-01-R8"],"dockets":[{"supporting_documents":[{"title":"Summary of FLM Conclusions and Recommendations and How the EPA Addressed the Comments","document_id":"EPA-R08-OAR-2026-1651-0017"},{"title":"Memo to docket_Meetings between EPA_ PacifiCorp_and State of Wyoming","document_id":"EPA-R08-OAR-2026-1651-0016"},{"title":"Email communication between the EPA and PacifiCorp_May 28 2026","document_id":"EPA-R08-OAR-2026-1651-0015"},{"title":"Wyoming permit number MD-6041_December 31 2009","document_id":"EPA-R08-OAR-2026-1651-0014"},{"title":"Wyoming permit number MD-5098_June 27 2008","document_id":"EPA-R08-OAR-2026-1651-0013"},{"title":"Wyoming EGU BART and Reasonable Progress Costs_October 28 2013","document_id":"EPA-R08-OAR-2026-1651-0012"},{"title":"PacifiCorp 2025 Integrated Resource Plan_March 31 2025","document_id":"EPA-R08-OAR-2026-1651-0011"},{"title":"PacifiCorp 2025 Integrated Resource Plan_January 30 2026","document_id":"EPA-R08-OAR-2026-1651-0010"},{"title":"North American Electric Reliability Corporation 2024 Long-Term Reliability Assessment_December 2024","document_id":"EPA-R08-OAR-2026-1651-0009"},{"title":"Letter from PacifiCorp to U.S. EPA Region 8_March 4 2026","document_id":"EPA-R08-OAR-2026-1651-0008"}],"agency_name":"EPA","documents":[{"comment_count":2,"comment_start_date":"2026-06-08","updated_at":"2026-06-10T01:57:06.651-04:00","comment_url":"https://www.regulations.gov/commenton/EPA-R08-OAR-2026-1651-0003","allow_late_comments":false,"id":"EPA-R08-OAR-2026-1651-0003","comment_end_date":"2026-07-24","regulations_dot_gov_open_for_comment":true}],"supporting_documents_count":16,"id":"EPA-R08-OAR-2026-1651","title":"Approval and Promulgation of Air Quality Implementation Plans; Wyoming; Regional Haze Federal Implementation Plan"}],"document_number":"2026-11436","effective_on":null,"end_page":34597,"executive_order_notes":null,"executive_order_number":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2026/06/08/2026-11436.xml","html_url":"https://www.federalregister.gov/documents/2026/06/08/2026-11436/approval-and-promulgation-of-air-quality-implementation-plans-wyoming-regional-haze-federal","images":{},"images_metadata":{},"json_url":"https://www.federalregister.gov/api/v1/documents/2026-11436?publication_date=2026-06-08","mods_url":"https://www.govinfo.gov/metadata/granule/FR-2026-06-08/2026-11436/mods.xml","not_received_for_publication":null,"page_length":9,"page_views":{"count":308,"last_updated":"2026-06-13 20:15:03 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2026-06-08/pdf/2026-11436.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":"https://public-inspection.federalregister.gov/2026-11436.pdf?1780663515","publication_date":"2026-06-08","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2026/06/08/2026-11436.txt","regulation_id_number_info":{},"regulation_id_numbers":[],"regulations_dot_gov_info":{"supporting_documents":[{"title":"Summary of FLM Conclusions and Recommendations and How the EPA Addressed the Comments","document_id":"EPA-R08-OAR-2026-1651-0017"},{"title":"Memo to docket_Meetings between EPA_ PacifiCorp_and State of Wyoming","document_id":"EPA-R08-OAR-2026-1651-0016"},{"title":"Email communication between the EPA and PacifiCorp_May 28 2026","document_id":"EPA-R08-OAR-2026-1651-0015"},{"title":"Wyoming permit number MD-6041_December 31 2009","document_id":"EPA-R08-OAR-2026-1651-0014"},{"title":"Wyoming permit number MD-5098_June 27 2008","document_id":"EPA-R08-OAR-2026-1651-0013"},{"title":"Wyoming EGU BART and Reasonable Progress Costs_October 28 2013","document_id":"EPA-R08-OAR-2026-1651-0012"},{"title":"PacifiCorp 2025 Integrated Resource Plan_March 31 2025","document_id":"EPA-R08-OAR-2026-1651-0011"},{"title":"PacifiCorp 2025 Integrated Resource Plan_January 30 2026","document_id":"EPA-R08-OAR-2026-1651-0010"},{"title":"North American Electric Reliability Corporation 2024 Long-Term Reliability Assessment_December 2024","document_id":"EPA-R08-OAR-2026-1651-0009"},{"title":"Letter from PacifiCorp to U.S. EPA Region 8_March 4 2026","document_id":"EPA-R08-OAR-2026-1651-0008"}],"comments_count":2,"agency_id":"EPA","comments_url":"https://www.regulations.gov/docketBrowser?rpp=50&so=DESC&sb=postedDate&po=0&dct=PS&D=EPA-R08-OAR-2026-1651","supporting_documents_count":16,"docket_id":"EPA-R08-OAR-2026-1651","document_id":"EPA-R08-OAR-2026-1651-0003","regulation_id_number":null,"title":"Approval and Promulgation of Air Quality Implementation Plans; Wyoming; Regional Haze Federal Implementation Plan","checked_regulationsdotgov_at":"2026-06-11T08:55:04Z"},"regulations_dot_gov_url":"http://www.regulations.gov/commenton/EPA-R08-OAR-2026-1651-0003","significant":null,"signing_date":null,"start_page":34589,"subtype":null,"title":"Approval and Promulgation of Air Quality Implementation Plans; Wyoming; Regional Haze Federal Implementation Plan","toc_doc":"Wyoming; Regional Haze Federal Implementation Plan","toc_subject":"Air Quality State Implementation Plans; Approvals and Promulgations","topics":["Air pollution control","Ammonia","Carbon oxides","Environmental protection","Incorporation by reference","Intergovernmental relations","Lead","Nitrogen oxides","Ozone","Particulate matter","Reporting and recordkeeping requirements","Sulfur oxides","Volatile organic compounds"],"type":"Proposed Rule","volume":91}