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Ground-level Ozone Pollution

Proposed Determinations of Attainment by the Attainment Date, Extensions of the Attainment Date, and Reclassification of Several Areas Classified as Moderate for the 2008 Ozone Air Quality Standards

As required by the Clean Air Act, EPA has proposed actions for 11 nonattainment areas classified as  moderate for the 2008 ozone National Ambient Air Quality Standards. These areas were required to attain the standards by July 20, 2018.  After evaluating air quality monitoring data for the years 2015 - 2017, EPA is proposing that:

  • Baltimore, MD, and Mariposa, CA, attained the standards by the attainment date;
  • Both the Denver-Boulder-Greeley-Ft. Collins-Loveland, CO, and Sheboygan County, WI, areas are eligible for a 1-year attainment date extension to July 20, 2019; and
  • Seven areas in CA, CT, IL, IN, NJ, NY, TX, and WI failed to attain the standards by their attainment date and do not qualify for a 1-year attainment date extension. These areas would be reclassified as Serious. The new attainment date for the reclassified areas would be July 20, 2021.
EPA will accept public comment on this proposal through February 22, 2019.

EPA will hold a public hearing on this proposed action. The hearing will be held at EPA's Offices in Washington, DC. on Friday, February 15, 2019, from 9:00 a.m. –  5:00 p.m. (local time) or 2 hours after the end of testimony from the last registered speaker.  

Pre-registration for the hearing  is closed. If you have questions about the hearing, you may contact Yvonne Johnson at

Read the notice extending the public commnet period and announcing the public hearing.

See the list of registered speakers below.

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