EPA Issues Final Rule Tightening Ozone Ambient Air Quality Standard

May 16, 2008
Client Alert Newsletter May 2008

On March 12, 2008, the U.S. Environmental Protection Agency ("EPA") announced a final rule tightening the National Ambient Air Quality Standard ("NAAQS") for ozone. The new eight-hour standard of 0.075 pm. replaces the existing standard of 0.08 pm. EPA's July 2007 rulemaking proposal, which proposed a range of 0.070-0.075 pm., had been sharply criticized by some groups, because the agency's Clean Air Scientific Advisory Committee had recommended a revised NAAQS standard between 0.060 and 0.070 pm. The final rule has likewise been criticized, although EPA estimates that the tightened standard will yield health benefits valued between $2 billion and $19 billion. The revised NAAQS will trigger a series of implementation actions, including state attainment designation recommendations due in June 2009, EPA's finalization of the designations in 2010, and state implementation plan revisions in 2013. Attainment dates, depending on nonattainment classification, will range from 2013 to 2030.