Bloomberg: Power producers would have to curb the tainted water they discharge into waterways under a proposal issued by the Environmental Protection Agency on Friday, the latest in a series of rules focused on utilities that burn coal. The agency proposed four options for regulating the waste from power plants, which are the top source of pollutants in streams, rivers and other waters. The final rules would have the most impact on coal-fired plants, which are the primary source of the pollutants, and would...