Unruly Mercury

A FEDERAL COURT recently overturned a controversial Environmental Protection Agency regulation requiring coal-fired power plants to reduce mercury emissions. While the Bush Administration is appealing the decision, utilities' emission of the neurotoxic metal may still face regulation by state agencies.

Environmental activists, backed by the research arm of Congress, say that because the federal rule has been vacated, the Clean Air Act must now require states to review plans for new coal-fired power plants or modifications to existing units. State regulators will also have to require the facilities to install mercury controls, they say. Attorneys for the utility industry, however, say that after the court's ruling, the only regulation of mercury emissions from power plants remaining is a handful of laws and rules that states adopted in recent years.

In a case brought by 17 states and backed by environmental groups, the U.S. Court of Appeals for the District of Columbia Circuit determined in February that EPA's 2005 "Clean Air Mercury Rule" was unlawful (C&EN, Feb. 18, page 6). In mid-March, the court officially nullified the rule. The regulation had set a nationwide cap on mercury releases from power plants and allowed utilities to trade permits for emitting the metal. Utilities favor the rule, but many states and environmental groups argue that EPA should require each coal-fired facility to install pollution control technology to capture mercury releases.

John D. Walke, senior attorney with the Natural Resources Defense Council, says regulation by states took effect as soon as the court wiped the mercury regulation off federal rulebooks. States are obligated to regulate mercury emissions from newly built power plants or existing plants undergoing modifications, he tells C&EN. This should continue until EPA issues a new rule on mercury, he argues.

A recent legal analysis of the decision by the Congressional Research Service (CRS) supports Walke's position. "If the court's ruling stands, it would appear to guarantee that all new and some existing EGUs [electricity generating units] will be subject to more stringent mercury control standards in the immediate future," the analysis says.

An organization of state and local clean air regulators is gearing up to implement mercury controls on new and modified power plants. "We plan on helping states to meet those requirements," says S. William Becker, executive director of the National Association of Clean Air Agencies.

Walke says that these requirements date from December 2000, during the last weeks of the Clinton Administration, when EPA listed power generators that emit mercury as sources of hazardous air pollution. This action triggered a provision in the federal Clean Air Act that effectively required states to regulate mercury from any newly built or modified power plants by requiring installation of maximum achievable control technology, he tells C&EN. The provision stayed in effect until 2005, when, under the Bush Administration, EPA reversed the Clinton era decision by delisting power plants and issuing the cap-and-trade rule.

The utility industry maintains, however, that the court's ruling does not prompt instant state regulation.

Scott Segal, director of the utility industry group the Electric Reliability Coordinating Council, says the court's order carries one immediate consequence: It officially removes EPA's mercury regulation from the federal rulebooks. The claim that it also requires states to start regulating mercury from new or modified power plants "is not in the decision, and it's not correct," he tells C&EN.

In the midst of this disagreement, EPA isn't saying much. Agency spokesman Timothy Lyons says that EPA continues to evaluate the impact of the court's decision, including the possible implications for states.

ULTIMATELY, EPA may issue a new regulation controlling mercury emissions from power-generating facilities, one that requires each plant to install maximum achievable control technology. But there are two reasons that the new rule will take years to establish. First, it is unlikely that the Bush Administration, which is appealing the court's decision, could or would come up with a proposed version of a new rule before the President's term ends in January 2009. Second, it would probably take the next Administration at least six months to develop policy positions on the mercury issue. From that point, EPA would need 18 months to propose and then finalize a rule.

CRS predicts that setting the new standards might take as long as three years because EPA will have to gather new data on mercury emissions and the effectiveness of control technologies.

The appeal of the February decision, meanwhile, may continue regardless of who wins the White House in November. If the federal appeals court turns down the Bush Administration's request to review the ruling, an appeal to the U.S. Supreme Court is possible. If the high court agrees to hear the case, the utility industry could continue arguing the case, even if the new president chooses not to press the matter further and EPA issues a maximum achievable technology rule.