Environmental groups are targeting southern Indiana and Western Kentucky power plants, naming them among the dirtiest in the country. In a new report issued by the Environmental Integrity Project , four coal fired power plants in Indiana and two in Kentucky are named among the 50 dirtiest in the country. The study suggests those plants produce dangerous levels of carbon dioxide, sulfur dioxide and mercury. Contributers to the study say cleaning up those heavy polluters should be a top priority for states... They're also opposing construction of new, coal fired plants, instead urging power companies to invest in renewable energy sources like bio-fuels, wind, and solar energy. Bruce Nilles of the sierra club spoke about the study today, suggesting that plans to build new coal power plants in Indiana and Kentucky could seriously add to the pollution problem, even if they are built with so called "clean coal" technology.