Response to Clean Air Act Section 176A Petition From New Hampshire

Official abstract: The Environmental Protection Agency (EPA) is proposing to grant a Clean Air Act (CAA or Act) petition submitted by the state of New Hampshire on December 24, 2025. The petition requests that the EPA remove the State of New Hampshire from the Ozone Transport Region (OTR) based on New Hampshire's continued attainment of the ozone National Ambient Air Quality Standards (NAAQS) and technical analyses demonstrating that the additional control of emissions from the state will not significantly contribute to ozone attainment in any area in the OTR. The OTR was established by the 1990 Clean Air Act Amendments and included the States of Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, the District of Columbia, and portions of northern Virginia.