Mercury Aired

AIR POLLUTION

States and environmental groups are gearing up to sue EPA over a rule that the agency issued last week to control mercury emissions from coal-fired power plants.

The regulation would cut the 48 tons of mercury spewed out by U.S. power plants each year to 38 tons by 2010 and to 15 tons after 2018. Electricity generators will receive credits allowing them to emit a specified amount of mercury. Plant operators that curb their releases below this amount can sell excess allowances to facilities that need more.

States and environmental groups are preparing lawsuits arguing that EPA went afoul of the Clean Air Act in creating a cap-and-trade program for a pollutant that is neurotoxic. They contend that EPA instead should force every U.S. coal-fired power plant to install equipment to cut mercury emissions.

EPA officials respond that government lawyers carefully considered this issue and are ready to defend the new rule in court.

The agency acknowledges that generators will not need to install special equipment to achieve the 2010 mercury limits. The reduction will happen as a by-product of another regulation requiring power plants to curb releases of sulfur dioxide and nitrogen oxides. Issued on March 10, that rule is expected to reduce emissions of SO₂ and NO_x from electricity generators in 28 eastern states.

State regulators, environmental activists, and public health advocates also say the regulation gives utilities too long to curb their mercury emissions.

William O'Sullivan, air quality director for New Jersey, says of the mercury regulation: "The emission limits in this rule are not nearly stringent enough and do not even reflect the level of control capable by currently available technology." New Jersey is requiring its power plants to cut their emissions of mercury by 90% by the end of 2007.

But Scott Segal, director of the Electric Reliability Coordinating Council, says no control technology now exists to achieve the levels of mercury required in the final phase of the EPA regulation. Segal, who praises the cap-and-trade approach, says development continues on technologies to remove large amounts of mercury from different plant configurations and various types of coal.

The new rule's goal is to eventually reduce mercury levels in fish eaten by pregnant women, since the nervous systems of developing babies can be damaged by the metal.

EPA emphasizes that mercury emissions from U.S. coal-fired power plants are responsible for only a small amount of the metal accumulating in U.S. waters. Americans eat fish caught all over the world, it adds.

The Bush Administration last month helped scuttle a proposal for a global treaty to lower industrial releases of mercury. It successfully pushed for a voluntary program to control emissions internationally (C&EN, March 7, page 30).