BOISE, Idaho — A deep well used to monitor radioactive and other contamination in a giant Idaho aquifer is back in service after a three-year absence, a contractor for the U.S. Department of Energy says.
Fluor Idaho in a statement Tuesday said scientists determined contamination discovered in the 1,110-foot (340-meter) well was caused by an industrial solvent in the well's tubing fluid and was not in the ground water.
Fluor Idaho is a contractor that manages radioactive pollution cleanup at the Energy Department's 890-square-mile (2,305-square-kilometer) site in eastern Idaho that includes the Idaho National Laboratory. The site sits above the Eastern Snake Plain Aquifer, which supplies water to cities and farms in the region.
The company said it removed the solvent from the well with an innovative device, and it found two other wells with similar problems that are going through the same process and should be back in use this summer.
Marc Jewett is the director of the company's Environmental Restoration program for Idaho. He said that a device was lowered into the first well tube that removed the solvent, and that repeating that process reduced the contamination in the tube "to such a level that we can return the well to service and begin collecting aquifer samples in the immediate future."
The federal site in high-desert sagebrush steppe opened in 1949 and includes various components. Among them is a U.S. Navy site that handles fuel waste from the nation's fleet of nuclear-powered warships and the Idaho National Laboratory, considered the nation's leading nuclear research lab. It has also been used to store radioactive waste brought in from other states.
Officials say contamination from the federal site reached the aquifer through injection wells, unlined pits and accidental spills, mainly during the Cold War era before regulations to protect the environment were put in place.
The U.S. Geological Survey monitors about 175 wells in the area to track radioactive contamination and other pollutants in the Eastern Snake Plain Aquifer below the site. It takes from 50 to 700 years for water to travel through the Lake Erie-sized aquifer and emerge in springs near the small city of Twin Falls.
A report it released in 2017 said the aquifer is as free of radioactive contamination and other pollutants as it has been in more than six decades of monitoring.
U.S. Geological Survey scientist Roy Bartholomay, who monitors the wells, was unavailable for comment Wednesday because of the federal government shutdown.