Federal “Good Neighbor Plan” for the 2015 Ozone National Ambient Air Quality Standards; Notice on Remand of the Record of the Good Neighbor Plan To Respond to Certain Comments

The Environmental Protection Agency (EPA) is addressing certain comments that were submitted on the proposed Good Neighbor Plan that the Supreme Court of the United States concluded the EPA had likely not sufficiently addressed in the final Good Neighbor Plan. The EPA is providing a fuller explanation of its reasoning at the time of its action in response to these comments. The Good Neighbor Plan addressed 23 states' obligations to eliminate significant contribution to nonattainment or interference with maintenance of the 2015 ozone national ambient air quality standards (NAAQS), pursuant to the "good neighbor" provision of the Clean Air Act (CAA or Act). On September 12, 2024, the D.C. Circuit Court of Appeals remanded the record of the Good Neighbor Plan to the EPA to permit the Agency to further respond to comments related to the Good Neighbor Plan's operation if one or more upwind States were no longer participating. In this document, the EPA responds to the comments by more fully explaining why the Good Neighbor Plan appropriately defines each state's obligations, regardless of the status of the rule in other states, and can be implemented without modification in any individual state or combination of states covered by the rule.