The U.S. Department of Energy says the cleanup of a 20-acre waste site near the Y-12 nuclear weapons plant in Oak Ridge, Tenn., has significantly reduced the area's groundwater contamination.
Before the cleanup project, the average uranium concentration was 400 picocuries per liter of water. Ten months after cleanup, that level had dropped to about 8 picocuries per liter, which is within drinking-water standards.
The cleanup included the excavation of about 80,000 cubic yards of nuclear and other hazardous waste from a site about 1.5 miles from Y-12.
The waste was burned and buried at the site between 1943 and 1970. Over the years, some of the radioactive material has seeped into the groundwater.
"We are pleased that this remedy has performed as promised," Steve McCracken, Department of Energy cleanup manager, said in a statement.
Sevenson Environmental and STEP Inc. was subcontractor on the project for Bechtel Jacobs Co., DOE's environmental manager in Oak Ridge.