By JENNIFER 8. LEE New York Times

Tuesday, March 16, 2004

Washington -- Under pressure from environmental groups and state officials, the Bush administration says it is rethinking its proposed rules limiting mercury emissions from coal-burning power plants and as a result may tighten the proposal.

Administration officials have become uncomfortable with analyses indicating that if the proposal is adopted, the Environmental Protection Agency could miss, perhaps by more than a decade, its own 2018 deadline for reducing those emissions by 70%.

Michael O. Leavitt, who took the helm of the environmental agency only weeks before the proposed regulations were announced, was largely uninvolved in their initial development. But in the last several weeks, EPA employees say, he has immersed himself in briefings about the rules.

On Friday, Leavitt briefed the White House, indicating that his agency would consider exploring tougher alternatives or adjustments to the proposal.

"What our models now show is that we wouldn't get there as soon as we expected we would," Jeffrey Holmstead, assistant environmental protection administrator in charge of the air office, said of the agency's goal.

Coal-burning power plants are the nation's largest source of unregulated emissions of mercury, spewing about 48 tons of it a year, equivalent to about 40% of all human-caused mercury emissions. But court-ordered deadlines, resulting from a lawsuit that environmental groups brought against the Clinton administration, mandated the EPA's introduction of a mercury proposal by last Dec. 15, with a final rule due on Dec. 15 of this year.

The proposal that the Bush administration offered in December, and that it is now reconsidering, would allow power plants to buy and sell among themselves, starting in 2010, a limited right to pollute with mercury, much as with the current regulation of sulfur dioxide, a component of acid rain.

Environmental groups, which criticize that approach as questionable under the Clean Air Act, favor a stricter system that would force all power plants to install pollution controls by 2007, a deadline that utility companies call technically unfeasible.

EPA staff members have complained that analysis has been unusually limited for a regulation so complex.

Mercury has become a politically delicate issue for the administration, particularly in the Great Lakes states, some of them crucial in the presidential election and almost all with mercury- contamination warnings about eating fish.

Mercury is also an issue among another important constituency: women. The Centers for Disease Control and Prevention has estimated that one woman in eight has a mercury concentration in her body that exceeds safety levels.