A draft report issued this month by the U.S. Environmental Protection Agency (“EPA”) calls for substantially tightening air quality standards for fine particulate matter.  The report comes as EPA prepares to issue a draft proposal in November 2010 and a final rule in July 2011 for annual and 24-hour fine particulate matter standards.

EPA last revised the fine particulate matter standards in 2006, tightening the allowable concentration from 65 to 35 micrograms per cubic meter when measured over a 24-hour period. It left in place the annual standard of 15 micrograms per cubic meter.  Environmental groups sued EPA over the revised standards, arguing that EPA ignored staff and scientific advisors’ recommendations for a lower annual standard of between 13 and 14 micrograms.  A federal appeals court ruled against the Agency, finding that EPA had failed to adequately explain why a level of 15 micrograms adequately protects public health and welfare and visibility.  EPA is now reconsidering the annual standard in response to the court ruling.

There are already 120 counties nationwide that currently are nonattainment for fine particulate matter, based on EPA’s air monitoring data from 2006 to 2008.  See here for discussion of 2007 particulate matter implementation rule.  In the new draft report, EPA scientists conclude that the annual standard should be lowered to protect public health and the environment, despite EPA data showing that fine particulate matter measured annually fell by 19 percent between 1990 and 2008.  The report suggests two options: (1) lowering the annual standard to between 12 and 13 micrograms per cubic meter while either retaining or lowering the 24-hour standard to between 30 and 35 micrograms, and (2) lowering the annual standard to between 10 and 11 micrograms and lowering the 24-hour standard to between 25 and 30 micrograms.  

Meanwhile, on March 17th, two environmental groups petitioned the National Park Service to certify that 12 coal-fired boilers and one coal-fired cement kiln in Colorado are contributing to visibility problems in Rocky Mountain National Park.  A certification would require Colorado to adopt “best available retrofit technology” requirements to reduce the nitrogen oxides, sulfur dioxide, and particulate matter emissions from the plants.