WASHINGTON — A federal appeals court on Tuesday overturned a federal rule that would have forced 28 states to clean up air pollutants drifting from their power plants downwind to other states.
In a 2-1 ruling, a panel of the U.S. Court of Appeals for the District of Columbia said the Environmental Protection Agency had exceeded its authority in the way it apportioned the cleanup work among the upwind states.
The EPA was trying to address a problem that has vexed the air pollution control system for at least three decades: how to deal with states whose own air was clean enough, but were hosts to power plants, refineries and other industrial plants that emitted sulfur dioxide and nitrogen oxide pollutants that prevented neighboring states from attaining the level of cleanliness required under federal law.
The rule thrown out, called the Cross-State Air Pollution Rule, was the agency's attempt to carry out a court-ordered fix on an earlier version, the 2005 Clean Air Interstate Rule.
The court said the EPA was authorized to set rules that would require upwind states "to bear responsibility for their fair share of the mess in downwind states."
But the EPA had improperly required states "to reduce their emissions by more than their own significant contribution to a downwind state's nonattainment," according to the opinion.
The EPA's rule also violated the Clean Air Act because it failed to let the states submit their own plans to comply and imposed a federal plan instead, the court said. The statute leaves it to the states to decide how they will meet federal standards.
Several power companies challenged the EPA rule, and were supported by more than a dozen states, mostly in the South and Midwest. North Carolina supported the rule, as did some mid-Atlantic and New England states.