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Ground-level Ozone Pollution

Reasonable Further Progress, Attainment Demonstration, and Related Requirements for Ozone Nonattainment Areas Meeting the Ozone National Ambient Air Quality Standard

This memorandum details the legal rationale for interpreting certain Clean Air Act (CAA) provisions so as not to require areas that are meeting the ozone standard to make the SIP submissions to EPA described in the provisions as long as the areas continue to meet the standard. It also describes the process by which EPA will determine that an area is attaining the ozone standard and need not make these SIP submissions.

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