On May 1, the Environmental Protection Agency released the list of counties not meeting the 2008 ozone standards of 75 parts per billion (ppb). This list includes 45 areas. Most areas have been on the non-attainment list previously, except for three new areas in two states — California and Wyoming.
The current ozone standards of 75 ppb have been in place since 2008. EPA has worked with states and tribes, and through a public comment period, to identify areas of the country that do not meet the standard. The agency credits ongoing improvements in air quality by states, tribes and local governments as a big reason why more areas were not classified as non-attainment.
The ozone rule was originally proposed by the EPA in January 2010. The agency proposed to change the current primary ozone standard of 75 ppb to a range of 60–70 ppb. The White House estimated the cost of implementation to be between $19 billion and $90 billion.
Under the stricter standards, as originally proposed, almost 650 counties would be designated as non-attainment.
But in September 2011, President Obama chose to withdraw the tighter proposal due to “reducing regulatory burdens and regulatory uncertainty.” However, the standard will be revisited in 2013. Under the Clean Air Act, every five years the EPA is required to review and revise, if necessary, current air quality standards.
Ozone is primarily created through emissions from cars, power plants, industrial facilities, electric utilities and other sources. Ozone can also be created by indoor equipment such as printers and copiers.
Since both sunlight and hot weather precipitate its formation, ozone is known as primarily a summer pollutant. Both urban and rural areas can have high levels of ozone due to airborne transport of pollutants from hundreds of miles away.