On August 23, the US Court of Appeals for the District of Columbia released its decision regarding petitions by Murray Energy Corporation and others, including Environmental Petitioners, regarding the 2015 Ozone National Ambient Air Quality Standard. There are over 120 million people in the U.S. exposed to unhealthy levels of ozone.
The decision was heavily based on scientific advice from the Clean Air Scientific Advisory Committee of the U.S. Environmental Protection Agency, which was chaired by CCEE’s Dr. H. Christopher Frey. CASAC’s Ozone Review Panel was comprised of nearly two dozen internationally prominent experts in a wide range of scientific disciplines pertaining to the public health and environmental impacts of ozone. The Court mentions CASAC 98 times in its decision.
The court upheld the “primary” health-based standard recommended by CASAC in 2014 and set by EPA in 2015 because CASAC provided scientific advice that EPA followed. However, the court remanded the “secondary’ standard, which pertains to impacts such as foliar injury, because EPA did not follow CASAC’s scientific advice and did not provide adequate rationale for departing from CASAC’s scientific advice. The Court explained that “EPA’s failure to explain why it could not accept data that CASAC deemed informative falls short of reasoned decisionmaking.” However, based on precedent from a Supreme Court ruling, the Court of Appeals agreed with the decision of both CASAC and EPA to refuse to consider cost in recommending and adopting, respectively, a revised standard.
This court decision illustrates the importance of having clearly stated and well-formulated scientific advice as the basis for setting air quality standards in the United States.
You can see Reuters news service coverage of this topic here.