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Ozone Designations

EPA responds to State and Tribal Recommendations for the 2015 Ozone Standards

On December 22, 2017, EPA responded to state and tribal recommendations by indicating the anticipated area designations for the portions of the country not already designated for the 2015 ozone standards.  These responses will start a 120-day period for states and tribes to provide additional information before EPA determines the final designations.  EPA will also be opening a 30-day comment period for the public to provide input on these designations before they are finalized.  For next steps, EPA will continue to work closely with our partners at the state, tribal, and local levels to finalize these area designations and improve ozone air quality.

Read EPA's responses to states and tribes as well as accompanying technical support documents.

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