The US Supreme Court has asserted limits to the Environmental Protection Agency’s authority to regulate greenhouse gases (GHGs) specifically but approved limitation of GHG emissions from plants subject to control of other pollutants covered by the Clean Air Act.
Oil industry groups applauded the expressions of restraint on EPA’s authority.
The case, Utility Air Regulatory Group v. EPA, questioned the extent of the EPA’s authority to require best available control technology (BACT) for GHG emissions. The agency requires BACT in prevention-of-significant-deterioration (PSD) permits required for new facilities and under Title V of the act for existing facilities.
In 2007, the court had ruled EPA could regulate GHG emissions under the Clean Air Act if it determined the emissions endangered human health. The agency made that determination, implemented regulations of GHG emissions for motor vehicles, and made stationary sources subject to its controls. To accommodate administration, it focused regulation of stationary sources on large emitters under a provision called a “tailoring rule.”
In its June 23 ruling, the high court held:
· The Clean Air Act doesn’t compel or permit EPA to interpret the act so as to require a new or existing emitter to obtain PSD or Title V permits only on the basis of potential GHG emissions.
· The EPA lacked authority to tailor the act’s “unambiguous numerical thresholds of 100 or 250 tons/year to accommodate its greenhouse-gas-inclusive interpretation of the permitting triggers.”
· The agency “reasonably interpreted the act” when it required sources that would need permits based on emissions of conventional pollutants to comply with BACT requirements for GHGs.
Groups on both sides of the challenge to EPA’s GHG regulatory authority welcomed the ruling.
Harry Ng, vice-president and general counsel of the American Petroleum Institute, called it a “stark reminder that the EPA’s power is not unlimited.”
Rich Moskowitz, general counsel of American Fuel and Petrochemical Manufacturers, also welcomed the limitation of EPA authority.
“The Court makes clear that an agency cannot rewrite the law to advance its political goals,” he said. “The Clean Air Act PSD program was never intended to regulate pollutants such as carbon dioxide in this fashion. This decision brings us closer to correcting a very costly regulation that would strain states’ resources and impose burdensome permitting requirements on some businesses.”
David Doniger, director of the Climate and Clean Air Program at the Natural Resources Defense Council, liked the decision for different reasons.
Doniger said the decision “builds on the Court’s prior decisions upholding most important Clean Air Act authority in the fight against global warming—EPA’s responsibility to set national standards to curb the carbon pollution emitted by automobiles and power plants.”