The U.S. Environmental Protection Agency says it will study whether to toughen regulation of large livestock farms that release manure and other pollutants into waterways. Runoff of waste and fertilizers from the operations — and from croplands where manure is spread — fouls streams, rivers and lakes. It’s a leading cause of algae blooms that create hazards in many waterways and dead zones in the Gulf of Mexico and Lake Erie. Read the full story by The Associated Press.