Supreme Court strikes down EPA rules on mercury emissions from power plants

Reuters / Gary Cameron
By not considering the monetary cost of its rules, the US Environmental Protection Agency (EPA) "unreasonably" interpreted the Clean Air Act in its efforts to limit mercury and toxic emissions from power plants, according to the US Supreme Court.

In a 5-4 ruling, the Supreme Court reversed a US Court of Appeals decision that said the EPA properly assessed health risks, but not regulatory compliance costs, when it issued rules to limit mercury and other hazardous emissions from electricity generators, mainly those powered by coal. The rules – set by the agency based under the Clean Air Act ‒ would have affected about 600 older US power plants lacking the technology to treat pollutants.

"EPA strayed well beyond the bounds of reasonable interpretation in concluding that cost is not a factor relevant to the appropriateness of regulating power plants," said the Court's majority, in a ruling by Justice Antonin Scalia.

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The court was charged with interpreting a section of the Clean Air Act that states the EPA "shall regulate" toxic emissions from power plants if the agency discovers "such regulation is appropriate and necessary." The Court had to decide if the EPA's interpretation of "appropriate" had taken into account the monetary costs of the regulations.

"It is not rational, never mind 'appropriate,' to impose billions of dollars in economic costs in return for a few dollars in health or environmental benefits," Scalia wrote.

The EPA issued the final rules in December 2011, deciding to limit emissions of mercury, heavy metals, and acidic gases from electric utilities. The agency argued that the rules would protect public health, and that they would result in savings of at least three times the regulatory compliance costs.

Industry and 23 US states challenged the rule in court, saying the EPA did not take costs into consideration. They posited that costs of complying would hit $9.6 billion overall, according to the Wall Street Journal.

Scalia insisted the Clean Air Act must factor in the costs of regulatory demands.

Writing for the minority, Justice Elena Kagan said the Court's ruling was an effective "micromanagement" of the EPA's mission that “deprives the agency of the latitude Congress gave it to design an emissions-setting process sensibly accounting for costs and benefits alike.”

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The decision also "deprives the American public of the pollution control measures that the responsible agency, acting well within its delegated authority, found would save many, many lives," Kagan added.

Groups opposed to the decision on Monday said the EPA could alter the emissions rule to meet the Supreme Court's demands.

"The Court has sided with the Dirty Delinquents -- the small percentage of coal-fired plants that haven't cleaned up -- and against the majority that are already protecting our children from mercury and other toxic pollutants," Fred Krupp, president of the Environmental Defense Fund, said in a statement. "It's critically important for our nation that these life-saving protections remain in place while EPA responds to the Court's decision, and EDF will focus its efforts on ensuring these safeguards are intact."