Feb 03, 2004 — For the first time, the U.S. government is preparing to regulate mercury emissions from coal-fired power plants. Part of the administration's proposal is to use a market-based approach, called "cap-and-trade." People in the energy business say "cap-and-trade" programs are proven tools to protect the environment at a lower cost. But some critics say a pollutant as toxic as mercury should have a more traditional and tougher regulatory program. The Great Lakes Radio Consortium's Erin Toner reports.