Note: Single-source report; awaiting corroboration.
The Savannah River Site (SRS) has completed the operational closure of several high-level radioactive liquid waste tanks, marking significant progress in managing Cold War-era waste. Tank 20 was the first tank certified closed by the South Carolina Department of Environmental Services (SCDES) on July 31, 1997, followed by Tank 17 in December 1997. These tanks, part of the F Tank Farm and constructed in the late 1950s and early 1960s, stored radioactive liquid waste from special nuclear material production. Additional tanks—including Tanks 18, 19, 5, 6, 12, and 16—also underwent operational closure between 2012 and 2016 in the F and H Tank Farms, with service dates ranging from 1956 to 1964.
Operational closure is defined by mutual agreement of the DOE, SCDES, and EPA that waste removal has been completed to the extent practicable from an engineering perspective. The tanks are then isolated from related transfer and chemical systems and stabilized by filling with grout.
DOE, SCDES, EPA, the U.S. Nuclear Regulatory Commission, SRS workers, and stakeholders worked jointly to ensure strict closure requirements, compliance with regulations, and long-term protection of people and the environment.
Before operational closure, a milestone called Preliminary Cease Waste Removal (PCWR) is reached, indicating agreement among DOE, EPA, and SCDES that closure performance objectives are likely to be met. This allows sampling and analysis to verify closure conclusions.