The Energy Department has until Friday to tell the Washington state Department of Ecology when the agency plans to close four single-shell tanks at the Hanford Site near Richland, Wash.
The schedule due to the state at the close of the week includes closure dates for tanks C-201, C-202, C-203, and C-204: four of the 16 single-shell tanks in Hanford’s C Farm that were were once filled with liquid waste left over from Cold War-era plutonium production.
DOE and its contractors have already drained these tanks to the levels specified in the Tri-Party Agreement that governs Hanford cleanup and now must close the tanks either by removing them from the site or filling them with cement to prevent what waste remains inside from leaking out.
Tanks 201 through 204 are the first of the 16 C Tank farms slated for closure, according to a late-November regulatory filing from DOE. All 16 tanks were once supposed to be closed by 2019, but the agency and Ecology agreed to a delay last year.
In total, there are 149 single-shell tanks at Hanford and 28 double-shell tanks. Pumpable liquids have been removed from leak-prone single-shell tanks, but the majority have not been emptied of sludge.
All told, the tank farms contain more than 55 million gallons of liquid waste that will eventually be turned into more easily storable glass canisters in the Waste Treatment Plant Bechtel National is building at Hanford. The plant must start treating the site’s briny, low-activity waste by 2023 and its sludgy, high-level waste by 2036, a federal judge ruled last year.
