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Clean Air Markets

Considerations for Identifying Maintenance Receptors Memo

This memo presents information that states may consider as they evaluate the status of monitoring sites that the Environmental Protection Agency (EPA) identified as potential maintenance receptors with respect to the 2015 ozone National Ambient Air Quality Standards (NAAQS) based on EPA’s 2023 modeling. States may use this information when developing state implementation plans (SIPs) for the 2015 ozone NAAQS addressing the good neighbor provision in Clean Air Act (CAA) section 110(a)(2)(D)(i)(I).

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