EPA Proposes Reclassification under 2008 and 2015 8-hour Ozone NAAQS

On April 13, 2022 the U.S. Environmental Protection Agency (EPA) proposed to reclassify the Denver Metro/North Front Range Nonattainment area under both the 2008 and 2015 8-hour ozone National Ambient Air Quality Standards (NAAQS):

• Under the 2008 8-hour ozone NAAQS of 75 parts per billion the EPA is proposing to reclassify the DM/NFR nonattainment area to Severe.
• Under the 2015 8-hour ozone NAAQS of 70 parts per billion the EPA is proposing to reclassify the DM/NFR nonattainment area to Moderate.

The EPA will be accepting written comments on the proposals through June 12, 2022 and will be holding a virtual hearing May 9, 2022. Proposed reclassifications will not take effect until EPA publishes the final reclassification in the Federal Register.

For more information on the RAQC’s planning efforts under both standards please see the RAQC’s Air Quality Planning page.