The SCOTUS ruling on mercury emissions stops years of momentum

The US Supreme Court recently put a stop to federal rules that would require power plants to clean up their emissions of the toxic metal, mercury.

The Environmental Protection Agency has been trying for the past 20 years to cut toxic mercury emissions. The effort paused during the Bush administration, but began anew under President Barack Obama. Writing for the majority, Justice Antonin Scalia said the agency had failed to consider the cost of the clean-up early enough in its rule making process.

“It's an unfortunate decision, in that EPA has to go back and do it over again,” says Carol Browner, head of the EPA under President Bill Clinton. “The good news is that [some] states had set mercury standards and industry had started to shut off and retire some of the older facilities. But, nevertheless, EPA's going to have to go back and redo some of the work.”

A lower court will decide if the EPA can indeed fix the problem or if the mercury rule must be thrown out entirely. That decision is being closely watched as a precedent for the lawsuits that are expected when rules limiting power plants' emissions of global warming gases are issued later this summer.

Browner thinks the EPA will successfully amend the law and seems skeptical of the court opinion.

"When you regulate one pollutant, you frequently get reductions in other pollutants," she says. "In this case, there were significant fine particle reductions, in addition to the mercury reductions. The court seems to be suggesting that you can't count those benefits.”

Under this section of the Clean Air Act, Browner explains, there’s a two-step process: first EPA examines the science to evaluate the danger to public health from a pollutant. Next, the agency looks at all the power plants that emit the pollutant on a type-by-type basis and sets pollution standards based on how much it would cost each type of plant. In this instance, Browner says, some plants would not have had to do anything under the new rules because EPA determined it wasn't cost-effective.

“So they did look at cost. They looked at it endlessly,” Browner says. “What Scalia and the majority are saying is EPA should have looked at cost in the first phase — during the science decision."

Interestingly, Browner notes, Scalia, who wrote the majority opinion on mercury, also wrote a majority opinion reviewing the soot and smog standards that Browner set as head of the EPA. It was a 9-0 ruling and Scalia agreed with EPA’s argument that the agency did not have to take cost into effect in setting these ambient air quality standards because Congress had told it to set a public health standard based on the best available science.

“I think the concern we should all have is that if we move towards setting environmental pollution standards — or workplace safety, or car safety standards or whatever — on a cost-benefit analysis, we may not get the kind of important science-based standards that have brought us safety and cleaner air and cleaner water,” Browner says.

“When you look at cost before you actually regulate a pollutant, you're guessing what the technology is going to be and the cost estimates inevitably are higher than they turn out to be once the standard is set,” she adds. “American innovation and ingenuity find a cheaper solution.”

Browner is hopeful that the consequences of the recent ruling will be small, because some states already have mercury requirements in place and a number of plants have already shut down in anticipation of the new rules. “But my sense is EPA will move quickly to fix the situation,” she says.

This story is based on an interview that aired on PRI's Living on Earth with Steve Curwood