The Environmental Protection Agency (“EPA”) on January 6, 2010 announced a drastic lowering of the National Ambient Air Quality Standards (“NAAQS”) for ozone, or smog, but neglected to give a specific number for the new standards.  The agency proposed to set the health-based primary standard for smog within a range of 60 to 70 parts per billion (ppb) when averaged over an 8-hour period.  EPA also proposed a separate secondary standard, aimed at protecting vegetation and ecosystems, within the range of 7 to 15 parts per million-hours.  Such a secondary standard would be based on a cumulative, weighted total of daily 12-hour ozone exposures to plants and crops over a three-month period.  The estimated cost for implementing the draft rule range from $19 billion to $90 billion.

The current primary ozone standard is 75 ppb.  There is no separate secondary standard. The current standard was proposed in March 2008 after a lengthy revision process spurred by a lawsuit requiring EPA to issue a final ozone NAAQS rule by March 12, 2008.  In a court filing on September 16, 2009, the Justice Department announced that the EPA would reconsider the Bush-era NAAQS for ozone.  EPA’s latest reconsideration of the ozone NAAQS was based on the previous scientific and technical record used in its March 2008 review. 

While environmentalists praised the new proposed standards, industry groups expressed concern that the regulations are not needed to protect public health and welfare and will impose undue economic burdens.  The American Petroleum Institute said in a statement that the action lacks scientific justification. “EPA acknowledges the newer studies on ozone ‘do not materially change any of the broad scientific conclusions regarding the health effects of exposure,’” the group said in a statement.  “Given that conclusion, there is absolutely no basis for EPA to propose changing the ozone standards promulgated by the EPA Administrator in 2008.”

In a separate rule, EPA proposed in July 2009 to modify the ozone air quality monitoring network design requirement to support a lower standard, requiring an estimated 270 new ozone monitors throughout the country.  EPA currently is considering comments received on the proposed monitoring requirements and plans to issue a final rule in coordination with the final new ozone standards.

EPA will finalize specific primary and secondary ozone standards in a final rule by August 31, 2010. The agency is proposing an accelerated schedule for designating areas for the primary ozone standard and is taking comment on whether to designate areas for a seasonal secondary standard on an accelerated schedule or a 2-year schedule.  Under the proposed accelerated schedule, states ultimately would be required to meet the primary standard between 2014 and 2031, with deadlines depending on the severity of the problem.