# 2025-05921: EPA nods to cleaner air plans in Pennsylvania towns 2025-05921, Air Plan Approval; Pennsylvania; Redesignation Request and Associated Maintenance Plan for the Liberty-Clairton Area for the 1997 Annual and 2006 24-Hour Fine Particulate Matter Standard and Maintenance Plan for the Allegheny County Area for the 2012 Annual Fine Particulate Matter Standard, is a Federal Register proposed rule from Environmental Protection Agency published 2025-04-07, effective Written comments must be received on or before May 7, 2025.; PRIA reads it as touching household money (as of 2026-10-07). - Canonical: https://policyrisk.com/federal-register/2025-05921 - As of: 2026-10-07 - Plain-text twin of the page above; the HTML and this file carry the same facts. ## Facts - Document number: 2025-05921 - Title: Air Plan Approval; Pennsylvania; Redesignation Request and Associated Maintenance Plan for the Liberty-Clairton Area for the 1997 Annual and 2006 24-Hour Fine Particulate Matter Standard and Maintenance Plan for the Allegheny County Area for the 2012 Annual Fine Particulate Matter Standard - Type: Proposed Rule - Agencies: Environmental Protection Agency - Citation: 90 FR 14939 - Published: 2025-04-07 - Effective: Written comments must be received on or before May 7, 2025. - Comments close: not stated - Significant: no - Touches household money: yes - Regulation identifier numbers: none - Last updated: 2026-10-07 ## In one line EPA nods to cleaner air plans in Pennsylvania towns ## Summary The EPA is giving a thumbs-up to Pennsylvania for cleaning up the air in Liberty-Clairton, officially recognizing it meets important air quality standards and approving a plan to keep it that way through 2035. Allegheny County gets a green light on its plan to control vehicle pollution through 2035, but it’s not yet officially meeting all air quality goals. These changes affect local communities and transportation planning, with public comments open until May 7, 2025. ## Abstract The Environmental Protection Agency (EPA) is proposing to approve a request from the Commonwealth of Pennsylvania to redesignate the Liberty-Clairton, Pennsylvania nonattainment area (Liberty-Clairton Area) to attainment for the 1997 annual and 2006 24-hour fine particulate matter (PM2.5) national ambient air quality standards (NAAQS or standard). The EPA is also proposing to approve, as revisions to the Pennsylvania state implementation plan (SIP), the Commonwealth's plan for maintaining the 1997 annual and 2006 24-hour PM2.5 NAAQS through 2035 for the Liberty-Clairton Area. Additionally, the EPA is proposing to approve the maintenance plan for the Allegheny County, Pennsylvania nonattainment area (Allegheny County Area) for the 2012 annual PM2.5 NAAQS through 2035. The maintenance plan includes 2017, 2026, and 2035 mobile vehicle emissions budgets (MVEBs) for mobile sources of PM2.5 and nitrogen oxides (NOX) for the Allegheny County Area. The EPA is proposing to find these 2017, 2026, and 2035 MVEBs for PM2.5 and NOX adequate and to approve these MVEBs into the Pennsylvania SIP for transportation conformity purposes. This action does not redesignate the Allegheny County Area to attainment for the 2012 annual PM2.5 NAAQS, as Pennsylvania withdrew its redesignation request specific to the Allegheny County Area. The redesignation request and maintenance plan were submitted by the Commonwealth of Pennsylvania Department of Environmental Protection (PADEP or Pennsylvania) on behalf of the Allegheny County Health Department (ACHD). This action is being taken under the CAA. ## Effects PRIA read - Liberty‑Clairton Redesignated to Attainment: benefit, medium. The EPA is proposing to redesignate the Liberty‑Clairton area to attainment for the 1997 annual PM2.5 NAAQS (15.0 micrograms per cubic meter) and the 2006 24‑hour PM2.5 NAAQS (35.0 micrograms per cubic meter) and to approve the area's maintenance plan that keeps these standards met through 2035. - Removal of 1997 Conformity Requirements in Liberty‑Clairton: benefit, low. If the Liberty‑Clairton redesignation is finalized, the 1997 primary annual PM2.5 NAAQS will be revoked for that area on the effective date of redesignation and the area will no longer be subject to transportation or general conformity requirements for the 1997 annual PM2.5 standard beginning on th… - PSD Program Applies After Redesignation: cost, medium. If Liberty‑Clairton is redesignated to attainment, the prevention of significant deterioration (PSD) program for the 1997 annual and the 2006 24‑hour PM2.5 NAAQS will apply in the Liberty‑Clairton area upon redesignation. - Allegheny County Maintenance Plan Approved Through 2035: benefit, medium. The EPA is proposing to approve the Allegheny County maintenance plan for the 2012 annual PM2.5 NAAQS through 2035, including contingency provisions intended to correct any violations of the 2012 annual PM2.5 standard through 2035. - Allegheny Nonattainment Requirements Remain in Place: cost, medium. This action does not redesignate the Allegheny County area to attainment for the 2012 annual PM2.5 NAAQS; all applicable nonattainment area requirements for the Allegheny County area for the 2012 annual PM2.5 NAAQS shall remain in place until Pennsylvania submits a redesignation request and the EPA… - 2017, 2026, 2035 MVEBs Approved for Transportation Conformity: mixed, medium. The EPA is proposing to find the 2017, 2026, and 2035 mobile vehicle emissions budgets (MVEBs) for PM2.5 and NOX for the Allegheny County area adequate and to approve them into the Pennsylvania SIP for transportation conformity purposes; the adequacy comment period for these MVEBs begins upon publi… ## Related documents - [2026-19071](https://policyrisk.com/federal-register/2026-19071): Partial Repeal of the Carbon Pollution Standards for Fossil Fuel-Fired Electric Generating Units, 2026-09-17 - [2026-19072](https://policyrisk.com/federal-register/2026-19072): Rescission of the Greenhouse Gas Findings for Fossil Fuel-Fired Power Plants and Repeal of Regulations for Power Plant Greenhouse Gas Emiss…, 2026-09-17 - [2026-18317](https://policyrisk.com/federal-register/2026-18317): Updated Definition of “Waters of the United States”, 2026-09-09 - [2026-14112](https://policyrisk.com/federal-register/2026-14112): Amendments and Nonconformance Penalties for Model Year 2027 and Later Heavy-Duty Highway Engines and Amendments to Inducement Provisions fo…, 2026-07-14 - [2026-13667](https://policyrisk.com/federal-register/2026-13667): Minor New Source Review Program Air Permitting Public Participation Requirements for State Implementation Plans, 2026-07-07 - [2026-13263](https://policyrisk.com/federal-register/2026-13263): Revisions To Establish the Sixth Unregulated Contaminant Monitoring Rule (UCMR 6) for Public Water Systems, 2026-07-01 ## Sources - [2025-05921 on federalregister.gov](https://www.federalregister.gov/documents/2025/04/07/2025-05921/air-plan-approval-pennsylvania-redesignation-request-and-associated-maintenance-plan-for-the) - [2025-05921 as published (PDF)](https://www.govinfo.gov/content/pkg/FR-2025-04-07/pdf/2025-05921.pdf) ## Related - [Previous: 2025-05920, Alcohol Facts Statements in the Labeling of Wines, Distilled Spirits, and Malt…](https://policyrisk.com/federal-register/2025-05920) - [Next: 2025-05799, Establishment of Class E Airspace; Blue Hill, ME](https://policyrisk.com/federal-register/2025-05799) - [All Federal Register documents](https://policyrisk.com/federal-register) Source: PRIA, https://policyrisk.com/federal-register/2025-05921 (as of 2026-10-07).