EPA concerned about Monsanto pollution control dam

Federal regulators are concerned that a dam built by Monsanto Co. earlier this year to trap phosphate mine runoff may be stopping more than just pollution. They say the dam has also halted millions of gallons of water in Sheep Creek that would otherwise help fill the Blackfoot River. The Environmental Protection Agency now wants the maker of Roundup herbicide to begin a costly treatment to remove selenium and heavy metals, then discharge clean water downstream, instead of capturing it in a 50-million-gallon lake behind the dam and using it for dust control on its mining roads.