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Ozone Pollution

Policy for Establishing Separate Air Quality Designations for Areas of Indian Country Memorandum

This 2011 memorandum provides EPA's policy regarding designating areas of Indian country separately from adjacent areas for the National Ambient Air Quality Standards (NAAQS), when requested by the relevant tribe for a particular area of Indian country (as defined at 18 U.S.C. § 1151).

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

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