July 14, 2008

Air Pollution

Court Overturns Regulation On Power Plant Emissions

EPA must start from scratch on rule to curb releases of SO₂ and NO_x

Cheryl Hogue

EPA needs to completely rewrite a Clean Air Act regulation designed to reduce power plant pollution linked to smog and acid rain, a federal court ruled on July 11.

The Bush Administration's 2005 Clean Air Interstate Rule, or CAIR, contains "several fatal flaws," the U.S. Court of Appeals for the District of Columbia Circuit said.

The regulation was aimed at reducing emissions of sulfur dioxide and nitrogen oxides from power plants in 28 eastern states and the District of Columbia. SO₂ causes acid rain, whereas NO_x is a precursor to ground-level ozone, or smog.

The rule set a cap for the pollutants across the region, rather than requiring all facilities to cut their releases of the substances. It allowed power plants that reduced their emissions the most to sell allowances to facilities that maintained or increased their releases of SO₂ and NO_x.

North Carolina and several utilities challenged the rule in court. North Carolina argued the regulation would allow power plants in neighboring states to emit more pollution that would blow into its jurisdiction. Utilities, meanwhile, argued that the rule was not fair in allocating allowances for pollution reductions.

The court agreed with both arguments. A three-judge panel directed EPA to start from scratch on a regulation to reduce SO₂ and NO_x from power plants. "No amount of tinkering ??? will transform CAIR, as written, into an acceptable rule," the court explained.

CAIR was one of the two hallmark regulations of the Bush Administration under the Clean Air Act. Federal courts have now struck both down. The other rule controlled mercury emissions from coal-fired power plants and was overturned in February (C&EN, Feb. 18, page 6).

The two decisions essentially leave it up to President George W. Bush's successor to rework the overturned rules, and they let utilities continue their current emissions until new regulations are finalized.

The rulings could push Congress into passing pending legislation that would reduce SO₂, NO_x, and mercury—and perhaps carbon dioxide, as well—from power plants.

Chemical & Engineering News

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