EPA Targets Mercury 'Hot Spots' at Power Plants

Jeffrey R. Holmstead, head of the EPA's Office of Air and Radiation, said the rule would eliminate "hot spots," or high mercury levels, in lakes and streams near big power plants. "We don't believe there will be any utility hot spots after this rule has gone into place," he said at a news conference to mark its signing.

But the regulation does not include any specific steps to address such hot spots, one of the most persistent mercury concerns among environmentalists, public health officials and many lawmakers. Rather, EPA officials say, the agency will "monitor this situation closely," and if new information confirms the existence of hot spots, it will "take action as needed."

The federal government and 45 states have issued warnings about fish consumption, particularly for women of childbearing age. Mercury that falls in lakes, rivers and oceans has been linked to neurological and developmental damage -- especially in newborns who were exposed to mercury in the womb, primarily from mothers who had eaten canned tuna and other fish. Coal-fired power plants are the largest source of mercury emissions in the U.S., producing 48 tons a year.

Holmstead said the rule -- along with a related regulation signed last week to reduce nitrogen oxides and sulfur dioxide -- would set national caps of 38 tons of mercury emissions from power plants in 2010, a 21% reduction from 1999 levels, and 15 tons beginning in 2018, or nearly 70% lower. Scrubbers required to remove the other two pollutants will decrease mercury emissions as well.

Because of market incentives in the rule, EPA officials said, there would be more rapid reductions initially, to 31 tons in 2010. But the 70% goal won't be reached until sometime after 2018, they said.

The EPA's plan is market-based, giving companies the option of cutting their own emissions of mercury or buying "credits" from other companies that do. That means some power plants won't reduce mercury emissions at all. Many critics seek emission ceilings at all plants, and argue that far deeper reductions are possible with current technology.