The US Environmental Protection Agency (EPA) is proposing to determine that the Denver Metro/North Front Range ozone non-attainment area did not meet the 2008 National Ambient Air Quality Standard (NAAQS) by the specified deadline and should be reclassified from a Moderate to a Serious non-attainment area.
EPA will be accepting public comment on the proposed action for a 30-day period beginning on 15 August and will hold a public hearing at the Agency’s regional office in Denver on 6 September.
The Denver area has been classified as a Moderate non-attainment area for the 2008 ozone 8-hour NAAQS since 2016. Based on an evaluation of air quality data collected from 2015 to 2017, the Agency is proposing to determine that the Denver Metro/Northern Front Range non-attainment area did not meet the standard within the timeframe established for 2008 Moderate ozone non-attainment areas.
Under the Clean Air Act, areas that do not attain national standards in a timely manner are reclassified to a higher non-attainment status, in this case from Moderate to Serious.
Under the Clean Air Act, the State of Colorado is responsible for developing a State Implementation Plan (SIP), which is a set of enforceable rules and programs to achieve compliance with national air quality standards. EPA’s action proposes due dates for Colorado to submit SIP revisions to attain the ozone standard, including the implementation of reasonably available control technologies.