P4 Production, a mining and phosphorous processing company owned by Monsanto, has agreed to pay a $1.4 million civil penalty for reported Clean Water Act violations at its South Rasmussen Mine, the U.S. Justice Department and the EPA announced Thursday.

P4 has also agreed to spend $875,000 on monitoring and to prevent pollutants from entering local waters.

“The Justice Department and the EPA are committed to enforcing the Clean Water Act to reduce pollution from mining and mineral processing operations,” said Ignacia Moreno, assistant attorney general for the Environment and Natural Resources Division of the U.S. Department of Justice. “Today’s settlement agreement will make Idaho’s waters cleaner by preventing selenium and other hazardous pollutants generated by P4’s mining operations from entering local creeks and wetlands.

The complaint against the mining company claims P4 discharged effluent containing selenium, cadmium, nickel and zinc, from the Horseshoe Overburden [dump] Area at the South Rasmussen Mine in southeast Idaho for a period of at least five years.

The Horseshoe dump is located at the headwaters of a tributary to Sheep Creek, which is a tributary of Lanes Creek, a tributary of the Blackfoot River, which flows into the Snake River, which flows in the Columbia River, which ends at the Pacific Ocean. A wetland is also located at the base of the dump.

Phosphate mines in the area, including the South Rasmussen mine, are known to contain high levels of selenium in their waste rock. Rain and weathering allowed the selenium to leach into nearby surface water. Sheep, horse and cattle deaths in southeast Idaho have been linked to selenium contamination of plants.

“Today’s settlement resolves a long-standing hazard to fish, wildlife and the environment in Southeast Idaho,” said Edward Kowalski, director of EPA’s Seattle Office of Enforcement and Compliance. “Selenium pollution is a serious problem in this part Idaho, and this enforcement action by EPA is one part of the long-term effort to clean up the phosphate patch.”

Monsanto uses South Rasmussen phosphate to manufacture Roundup, a herbicide.

The company did not admit any liability arising out of the consent decree. However, it has agreed to clean up discharges from the Horseshoe Overburden area within three years from the effective date of the consent decree.

P4 will also make monthly reports of water sampling in the area, and notify the EPA if the mine cannot comply with Clean Water Act requirements.

The consent decree is valid for five years.