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Ground-level Ozone Pollution

Proposed Action Finding the Denver Area Failed to Attain the 2008 Ozone National Ambient Air Quality Standard and Reclassification

August 8, 2019- As required by the Clean Air Act, EPA Region 8 has proposed action for the Denver Area classified as Moderate for the 2008 ozone National Ambient Air Quality Standards. This area was required to attain the standard by July 20, 2018.  Read the proposed action in the Federal Register.

EPA will hold a public hearing on this proposed action on September 6, 2019. 

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