The Environmental Protection Agency announced with the U.S. Department of Justice that P4 Production LLC, a subsidiary of Monsanto Co., agreed to the fine for alleged violations at its South Rasmussen mine in Idaho.
P4 during phosphate mining operations allegedly discharged wastewater containing high levels of selenium and heavy metals that eventually were found in the watershed of the Snake River.
Edward Kowalski, an enforcement officer at the EPA, said selenium pollution poses a direct threat to the health of the regional environment in Idaho. The agency said livestock deaths in the area were linked to selenium contamination of plants.
"Selenium pollution is a serious problem in this of part Idaho and this enforcement action by EPA is one part of the long-term effort to clean up the phosphate patch," he said in a statement.
The company agreed to perform downstream monitoring for five years and said it would work to prevent selenium from reaching sensitive wasters.
Phosphate mines contain high levels of selenium in waste rock.