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Ground-level Ozone Pollution

Implementation of the 2008 Ozone National Ambient Air Quality Standard (NAAQS) Memorandum

The purpose of this September 2011 memorandum was to clarify for state and local air agencies the status of the 2008 ozone NAAQS and to outline implementation steps moving forward.

To learn more about the implementation rule, visit the 2008 Ozone NAAQS Implementation Rule page.

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