Challenge to Designations for Fine Particulate Nonattainment Rejected

September 8, 2009
Client Alert Newsletter September 2009

Particulate matter, a mixture of microscopic solids and liquid droplets suspended in the air, is produced through a variety of combustion activities and certain industrial processes. According to the U.S. Environmental Protection Agency ("EPA"), exposure to particulate matter can cause a host of serious health problems, including heart and lung diseases, decreased lung function, asthma attacks, and even premature death. In 1997, EPA promulgated the National Ambient Air Quality Standards ("NAAQS") for fine particulate matter ("PM2.5"), which consists of two parts: a 24-hour standard of 65 micrograms per cubic meter (µg/m3), and an annual standard of 15 µg/m3. Using these standards, EPA designated various areas of the country as being in either nonattainment or attainment/unclassifiable with the 1997 PM2.5 NAAQS. These designations were published in December 2004 and became effective in April 2005. In our region, Bucks, Chester, Delaware, Montgomery, Philadelphia, Camden, Burlington, and Gloucester counties, among others in Pennsylvania and New Jersey, are designated as nonattainment for the 1997 PM2.5 NAAQS.

A number of cities, counties, and states that were designated by EPA in 2005 as being in nonattainment with the 1997 PM2.5 NAAQS filed petitions in the U.S. Court of Appeals for the District of Columbia Circuit challenging the designations. These counties argued, inter alia, that EPA ignored data from local emissions monitors and inconsistently applied its own guidelines in making the designations. On July 7, 2009, with the exception of one county, the Court unanimously rejected the petitions. With respect to the one exception, Rockland County, New York, the Court directed EPA to clarify its designation. States having at least one county designated as being in nonattainment are required to develop State Implementation Plans to demonstrate attainment with the 1997 PM2.5 NAAQS.