News Release 443

Southeast Missouri shows air quality violations as the 2009 ozone season ends

Volume 37-443 (For Immediate Release)
Contact: Renee Bungart

JEFFERSON CITY, MO, NOV. 19, 2009 -- The Bonne Terre monitor in Ste. Genevieve County exceeded the 2008 eight-hour ozone standard of 75 parts per billion on one day this year resulting in an air quality violation for 2009.

This exceedance has caused a violation of the standard based on an average of the last three years of monitoring data. Therefore, Ste. Genevieve County is in violation of the ozone standard and will likely be designated a nonattainment area under the 2008 eight-hour standard. This violation is further complicated by the U.S. Environmental Protection Agency's recent announcement that the 2008 eight-hour standard is under reconsideration. It is likely to be lowered to be more protective of public health and the environment.

Furthermore, while designation(s) recommendations under the 2008 eight-hour standard are on hold until EPA finalizes its re-evaluation of the standard, the 2009 monitoring data would support a nonattainment designation for Ste. Genevieve County. This violation and the possibility of a lowered ozone standard will require controls to reduce emissions of ozone precursors, which include volatile organic compounds and nitrogen oxides. The department will continue to work with southeast Missouri stakeholders who have been proactive in their pursuit of voluntary measures to protect air quality in the area. If a nonattainment designation occurs, the department will work closely with these stakeholders to develop control measures that are the most effective in terms of cost and emission reductions.

Ozone season begins April 1 and ends Oct. 31. Throughout the season, monitors in southeast Missouri record ozone levels at two sites. If EPA lowers the standard, it will reevaluate the most recent three years of monitoring data to determine if additional counties should be included in the nonattainment area.

Ground-level ozone is produced when volatile organic compounds mix with oxides of nitrogen on warm, sunny days with little or no wind. Man-made sources of VOCs and NOx include power plants, automobiles and trucks and other business and industries.

Exposure to ground-level ozone, or smog, can attribute to health problems. Those who suffer from asthma, heart disease, emphysema and other respiratory diseases could experience increased breathing difficulty. Long-term exposure to high levels of ozone can even cause healthy adults to experience breathing difficulty, especially those who exercise or work outdoors.

For more information on ozone, contact the department's Air Pollution Control Program at 800-361-4827 or 573-751-4817.