WASHINGTON — A fractured Supreme Court on Monday limited but did not eradicate the Environmental Protection Agency’s power to regulate certain greenhouse gas emissions.
In a complex 5-4 decision, the court’s conservatives declared the EPA cannot require stationary polluters to get permits solely because they might emit greenhouse gases. But if a permit is needed because of other emissions, the court acknowledged, regulators can compel use of certain greenhouse gas control technologies.
“We think it beyond reasonable debate that requiring permits for sources based solely on their emissions of greenhouse gases...would be incompatible with the substance of Congress’ regulatory scheme,” Justice Antonin Scalia wrote for the majority.
At the same time, the court agreed that for polluters already regulated for non-greenhouse gas emissions, the EPA can require use of so-called best available control technology.
“Applying BACT to greenhouse gases is not so disastrously unworkable, and need not result in such a dramatic expansion of agency authority, as to convince us that EPA’s interpretation is unreasonable,” Scalia wrote.
Scalia further stressed that the ruling Monday would only restrain the EPA from regulating a small percentage of greenhouse-gas polluters. The ruling, moreover, does not affect other Obama administration proposals to control greenhouse gases under different Clean Air Act provisions.
More than half of the nation’s states took sides in the dispute over federal authority to regulate stationary greenhouse gas emissions. Conservative lawmakers such as Senate Minority Leader Mitch McConnell, R-Ky., faced off against Southern California air pollution managers.
The decision consolidated six lawsuits that challenged Environmental Protection Agency rules. The lawsuits boiled down to one central question: Did the EPA overstep its bounds in regulating stationary greenhouse gas emissions based on an earlier determination that it could regulate such emissions from motor vehicles?
The Supreme Court’s four dissenters said Monday the EPA acted reasonably.
“What sense does it make to read the Act as generally granting the EPA the authority to regulate greenhouse gas emissions and then to read it as denying that power with respect to the programs for large stationary sources at issue here?” Justice Stephen Breyer questioned in dissent.
In a 2007 case, a closely divided court held that the Clean Air Act gave the EPA authority to regulate greenhouse gases, which contribute to global climate change. A hotter planet, in turn, has been linked to worsening ozone pollution, more intense forest fires, increased drought and a host of human respiratory problems, among other things.
Targeting six greenhouse gases, including carbon dioxide and methane, the EPA set tailpipe emission standards for cars and light trucks.
The EPA further reasoned that since the six greenhouse gases were deemed dangerous enough to regulate as tailpipe emissions, they must also fall under the pre-construction permit requirements for stationary emission sources, such as small industrial plants and agricultural facilities.
The Clean Air Act sets 100 or 250 tons per year, depending on the source, as the pollutant emissions threshold for when permits are needed. For greenhouse gas emissions, which are emitted from many sources, the EPA changed this to a more lenient 100,000 tons per year.
Keeping the stricter emission permit standards would have meant that tens, if not hundreds, of thousands of additional sources would face more regulatory burdens, according to the EPA.