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Ozone Designations

Extension of Deadline for Area Designations for 2015 Ozone Standards

The Administrator has determined that there is insufficient information to complete area designations for the 2015 ozone standards and is extending the deadline by one year, until October 1, 2018. Taking additional time will allow EPA to evaluate a host of complex issues regarding the 2015 ozone NAAQS and its implementation, such as understanding the role of background ozone levels and appropriately accounting for international transport; to develop additional flexibilities for states to comply with the ozone NAAQS; to consider completely all designation recommendations provided by state governors, including full consideration of exceptional events impacting designations; and to provide new agency officials time to complete their review of the 2015 ozone standards.

Read the Extension Notice

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