EPA Reopens Comments on Mercury Rule

EPA is accepting additional public comments on certain parts of its March final rule regulating mercury emissions from coal-fired power plants (C&EN, March 21, page 11). Although it is unusual for the agency formally to accept comments on rules after they are finalized, EPA is doing so in this case at the request of more than a dozen states and several environmental groups. The states and environmentalists oppose the part of the final rule that establishes an emissions cap on mercury releases and lets power plants trade emission allowances. They argue that the Clean Air Act does not allow pollution trading of toxic substances such as mercury. EPA says it will accept new comments on its cap-and-trade approach for regulating power-plant mercury. It will also allow comments related to a Bush Administration decision overturning the agency's 2000 legal determination that mercury releases from power plants should be reduced by emission control technology and not through a cap-and-trade program.