The Iowa Department of Natural Resources (DNR) said equipment failures at Roquette America's plant in Keokuk on Monday resulted in about 4,000 gallons of industrial wastewater entering the Mississippi River.
The state agency said the first spill occurred between 9:15 a.m. - 9:30 a.m. when a pump failed. The company said it was able to repair the pump and stop the discharge.
The second spill of about 3,500 gallons occurred about 5:00 p.m. The DNR said a faulty pump was again the source, but it's unclear if it was the same pump that caused the morning spill. The agency said it is looking into the cause of the second spill.
The contents of the releases might be ethanol and related compounds, but the DNR said nothing will be certain until a lab tests the results of collected samples.
The agency said it would continue to monitor the situation. It said this will help determine if the discharges exceeded the limits of Roquette America's National Pollutant Discharge Elimination System permit.