Proposed rule · 2025-11250

Air Plan Approval; Utah; Interstate Transport of Air Pollution for the 2008 8-Hour Ozone National Ambient Air Quality Standard

Pursuant to the Federal Clean Air Act (CAA or the Act), the Environmental Protection Agency (EPA) is proposing to approve a portion of a Utah State Implementation Plan (SIP) submission addressing interstate transport for the 2008 8-hour ozone national ambient air quality standard (NAAQS). The "interstate transport" provision requires that each state's SIP contain adequate provisions to prohibit emissions from within the state from significantly contributing to nonattainment or interfering with maintenance of the NAAQS in other states. In this action, EPA is only addressing the requirement prohibiting interference with maintenance, referred to as "prong 2," for the 2008 ozone NAAQS.