Proposed rule · 2026-01844

Interstate Transport Plan Review for the 2015 Ozone NAAQS

Pursuant to the Clean Air Act (CAA), the U.S. Environmental Protection Agency (EPA) is proposing to approve State Implementation Plan (SIP) submissions from eight States--Alabama, Arizona, Kentucky, Minnesota, Mississippi, Nevada, New Mexico, and Tennessee--regarding interstate transport for the 2015 8-hour ozone National Ambient Air Quality Standards (NAAQS). This action also explains why the EPA anticipates withdrawing previously proposed EPA error-correction actions related to interstate transport obligations for Iowa and Kansas and withdrawing previously proposed SIP disapproval actions for Tennessee, New Mexico, and Arizona. The "good neighbor" or "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. If finalized as proposed, this action would resolve these 10 States' obligations to eliminate significant contribution to nonattainment or interference with maintenance of the 2015 8-hour ozone NAAQS in other States.