An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Ground-level Ozone Pollution

Information on the Interstate Transport "Good Neighbor" Provision for the 2008 Ozone National Ambient Air Quality Standards (NAAQS) under Clean Air Act (CAA) Section 110(a)(2)(D)(i)(I)

This January 2015 memorandum is to provide information to states regarding State Implementation Plans (SIPs) to address the interstate transport “Good Neighbor” Provision of the CAA as it pertains to the 2008 ozone National Ambient Air Quality Standards (NAAQS).

For more information on the NAAQS, visit the 2008 Ozone NAAQS page.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.

Information on the Interstate Transport "Good Neighbor" Provision for the 2008 Ozone National Ambient Air Quality Standards (NAAQS) under Clean Air Act (CAA) Section 110(a)(2)(D)(i)(I) (PDF)(16 pp, 8 MB, January 22, 2015)