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Clean Air Markets

October 2017 Memo and Supplemental Information on Interstate Transport SIPs for the 2008 Ozone NAAQS

On October 27, 2017, EPA issued a memo to provide supplemental information to states and the Environmental Protection Agency (EPA) Regional offices.  This information supports the development or review of State Implementation Plans (SIPs) which address section 110(a)(2)(D)(i)(I) of the Clean Air Act (CAA), also called the “good neighbor” provision, as it pertains to the 2008 ozone National Ambient Air Quality Standards (NAAQS).

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