Proposed rule · 2026-08372

Utah; Northern Wasatch Front; 2015 8-Hour Ozone National Ambient Air Quality Standards; Reconsideration and Repeal of Finding of Failure To Attain and Reclassification to a Serious Nonattainment Area; Determination of Attainment by the Moderate Attainment Date But for International Emissions

The U.S. Environmental Protection Agency (EPA) is proposing to repeal the December 9, 2024, final rule in which the Agency determined that the Northern Wasatch Front (NWF) nonattainment area (NAA) in Utah failed to attain the Clean Air Act (CAA) 2015 ozone National Ambient Air Quality Standards (NAAQS) by the August 3, 2024, Moderate area attainment date, and reclassified the area by operation of law to Serious nonattainment (the "December 2024 Final Rule"). The EPA is also proposing to determine that the NWF ozone NAA would have attained the 2015 ozone NAAQS by the Moderate area attainment date but for emissions emanating from outside the United States (U.S.). If the EPA finalizes this proposed action, the NWF ozone NAA would no longer be subject to the CAA requirements pertaining to reclassification to Serious nonattainment upon failure to attain and would remain classified as Moderate for the 2015 ozone NAAQS.