By Brett Rosenberg
February 20, 2006

The Environmental Protection Agency announced plans to review implementation schedules February 3 for the National Ambient Air Quality Standards (NAAQS) concerning fine particulates in the air. The announcement addresses potential revisions to the timelines to implement both fine particle standards, known as PM 2.5 and inhalable coarse particle standards, known as PM 10-2.5. The EPA last revised PM 2.5 standards in 1997 and has not revised coarse PM standards since 1987.

While the EPA has not announced which of the areas out of attainment with current air quality standards the potential revisions may affect, more heavily polluted areas may receive additional time to comply with any new standards. Currently, there are approximately 224 areas out of attainment with existing PM 2.5 standards.

According to the EPA, this latest review, an Advanced Notice of Public Rule Making, is meant to alert the public that the agency is aware of, and considering the complex issues associated with implementing any new or revised particulate matter standards. The notice recognizes that there is not yet a final decision on whether or how to revise PM standards, but nonetheless addresses implementation issues if they are revised.

Assuming the EPA’s schedule to publish a final rule in September 2006 does not change, the likely effective date of the new PM 2.5 standard will begin in December 2006. This would trigger a period in which states recommend which areas are out of attainment with the new standard, based on monitoring data from 2005-2007. Based on these recommendations, EPA would then officially designate non-attainment areas by December of 2009, and they would become effective in April of 2010. By April of 2013, areas in non-attainment would be required to prepare State Implementation Plans, outlining the means to reach attainment. States and areas in non-attainment would have to meet the standards by April of 2015, although in some exceptional cases, the EPA would grant up to five additional years to comply.

The potential timeframe for PM 10-2.5 attainment is similar to PM 2.5. The main difference is that the EPA would take three additional years to collect and analyze data before seeking designation recommendations from the states.

In a sign that the EPA may be on the right track, both industry and environmental groups have expressed concern for various reasons. Some industry groups have expressed doubts that there is enough scientific evidence to support a tighter particulate matter standard. Environmental groups, meanwhile, have assailed the proposed revisions, stating that they are less stringent than those recommended in a recent report prepared by the EPA’s Clean Air Science Advisory Committee.

Particulate matter, also known as soot, contains microscopic solids and liquids that can lodge deep in lungs and is responsible for the haze seen in many cities. PM has been implicated in severe respiratory illness, such as asthma, and heart and lung disease. PM sources include tailpipe emissions, roads – both paved and unpaved, construction sites and smokestacks. The EPA is seeking public comments on implementing the proposed standards through mid April.