A group of 32 mostly Democratic senators acted last week to force a floor vote on a resolution that would overturn an EPA rule establishing a cap-and-trade program to reduce mercury emissions from coal-fired power plants. Sen. Patrick Leahy (D-Vt.) introduced the resolution last month under a 1995 law that allows Congress to overturn final agency rules with a majority vote.

A discharge petition filed by Leahy and 31 cosponsors on July 18 moves the resolution directly to the Senate floor. A vote might occur this month but could be delayed until after the August recess, according to a Leahy aide. Critics of the EPA regulation say the trading system would not reduce mercury emissions to levels required by the Clean Air Act. Leahy says the law requires EPA to set strict maximum achievable control technology limits on the facilities.

But Senate Environment & Public Works Committee Chairman James M. Inhofe (R-Okla.) argues that technology-based emission controls would force power plants to shift from coal to more costly natural gas. Rolling back the rule, he asserts, “will only delay progress in reducing mercury emissions.” EPA defends the March 15 regulation as the most cost-effective way to achieve major reductions in power plant mercury emissions (C&EN, March 14, page 30).