BISMARCK — An estimated 6,300 gallons of produced water spilled Monday, March 23, on a well pad in Billings County, N.D., according to a news release from the state Department of Environmental Quality.

Produced water is a mixture of saltwater, oil and sometimes, drilling fluids, that is created during oil and gas production.

Scout Energy Management reported the spill, which occurred southwest 10 miles from Belfield, was caused by faulty valve. The produced water impacted rangeland, which often cannot be used after such a spill. It's unclear how much of the spilled brine was recovered.

Department officials will continue investigating the spill and monitoring remediation efforts.