Final rule · 2026-21268

Approval and Promulgation of Implementation Plans; Arizona; Revisions to the Cleaner Burning Gasoline, Winter Oxygenated Fuel, and Gasoline Set-Aside Programs

The U.S. Environmental Protection Agency (EPA) is finalizing an approval of a revision to the Arizona State Implementation Plan (SIP) submitted by the Arizona Department of Environmental Quality (ADEQ). This revision includes statutes and regulations amending the Cleaner Burning Gasoline (CBG) program, which is a control measure in the greater Phoenix metropolitan area to reduce emissions of ozone- forming pollutants, carbon monoxide (CO), and particulate matter. Additionally, this revision addresses the Winter Oxygenated Fuel program to control CO emissions in the Tucson area. Finally, this revision repeals the Arizona Gasoline Set[hyphen]aside (GSA) Program, applicable to the 1971 carbon monoxide nonattainment area covering Maricopa County and a portion of Pima County. This SIP revision is administrative in nature. This final action updates the existing SIP- approved CBG program with revisions that have been adopted and implemented by the State to clarify requirements, update references, and enhance flexibility of the program and will not impose any additional costs or regulatory burdens.