Denver's Ozone Designation
On November 20, 2007, the Environmental Protection Agency (EPA) announced it
will not grant another extension date for Denver to meet EPA's 8-hour ozone
standard. The result is a federal nonattainment designation for the Denver area.
According to state-validated air quality data from 2005, 2006, and the first
three quarters of 2007, the Denver area violated the 8-hour federal health-based
standard for ozone. Based on this data, EPA has allowed a nonattainment designation
to take effect, thus the area has forfeited its participation in the Early Action
Compact program. The Denver Early Action Compact agreement was signed in December
2002 by the Regional Air Quality Council, Colorado Department of Public Health
and Environment, Colorado Department of Transportation, the Air Quality Control
Commission, the Denver Regional Council of Governments and EPA. The nonattainment
designation will require local and state officials to submit a new plan to reduce
ground-level ozone pollution.
In April 2004, EPA designated the Denver area (Adams, Arapahoe, Boulder, Broomfield,
Denver, Douglas, Jefferson and parts of Larimer and Weld counties) as nonattainment
for the 8-hour ozone standard, but deferred the effective date of the designation
based on a commitment from the State of Colorado, the Regional Air Quality Council
and others to implement ozone control measures sooner than required by the Clean
Air Act. This commitment was contained in the Denver Early Action Compact. In
return for this early action and for meeting certain milestones, EPA agreed
to defer the effective date of the nonattainment designation under the 8-hour
ozone standard. View
a map of the designated nonattainment area.
The latest deferral date was November 20. Because the state's monitoring data
shows a violation of the 8-hour ozone standard, EPA did not grant another extension,
and the 8-hour ozone nonattainment designation for the Denver EAC area is effective
November 20, 2007.
Ground-level ozone, a primary ingredient in smog, is formed when volatile organic
compounds and nitrogen oxides react chemically in the presence of sunlight.
Cars, trucks, power plants and industrial facilities are the primary sources
of these emissions. Ozone pollution is a concern during the summer months when
weather conditions needed to form ground-level ozone - stagnant air, lots of
sun and hot temperatures - normally occur. Ozone is unhealthy to breathe, especially
for people with respiratory diseases and for children and adults who are active
outdoors.
CDPHE, the RAQC and others are working on a revised state implementation plan
to address the Denver area's 8-hour ozone nonattainment issues. The revised
plan is expected to contain additional control measures that will ensure the
area meets the 8-hour ozone standard in the shortest time possible.
Please visit these sites for more information:
- 8-Hour Ground-level Ozone
Designations
provides a full listing of EPA's designations of state and tribal areas - Clean Air Rules of 2004
- Early Action Compacts