GAO: DOE Should Consider New Hanford Double-Shell Tanks

The Department of Energy should examine the idea of building new double-shell waste tanks at Hanford, the Government Accountability Office said in a report released today. Concerns have grown over the longevity of Hanford’s current set of 28 double-shell waste tanks, which are intended to store waste taken from the site’s single-shell tanks until it can be processed, since a leak was discovered between the inner and outer shells of Tank AY-102 in 2012. Corrosion has been found to a likely cause of the leak, which DOE has stressed does not pose a threat to the environment. According to the GAO report, though, “DOE has not yet assessed the extent to which the factors that led to corrosion that may have caused the leak in AY-102 are also present in the remaining 27 DSTs.”

According to the report, a rough estimate developed by DOE determined that it could take eight years and $800 million to construct new double-shell tanks. The GAO called on DOE to examine alternatives for creating new “RCRA-compliant tank space,” including new tanks, as well as to assess the extent to which the factors that may have led to the corrosion at Tank AY-102 may be present in other double-shell tanks and to update the Department’s schedule for retrieving waste taking into consideration delays in completing the Hanford Waste Treatment Plant and the risks associated with continuing to store waste in aging tanks.

In a response to the GAO, acting Assistant Energy Secretary for Environmental Management Mark Whitney said DOE accepted the GAO’s recommendations. He noted that DOE is looking at ways to add additional double-shell tank space, such as increasing operational limits in the tanks, operating an evaporator to reduce waste volumes and plans to use an exhauster to reduce surface liquids in the single-shell tanks. Whitney did not address, though, the idea of building new tanks in his response. The DOE Office of River Protection at Hanford declined to provide additional comment on the report yesterday.

The GAO report was released by Sen. Ron Wyden (D-Ore.), who sent a letter yesterday to DOE calling on the Department to provide within 90 days a schedule and plan for implementing each of the GAO’s recommendations. “The tanks at Hanford—both single shell (SST) and double shell (DST)—are in deteriorating condition and the schedule for addressing the problem is slipping inexorably into the future. Although the Department of Energy (DOE) has expanded its program to monitor leaks from the tanks, I am deeply concerned about what continues to be a policy of watch-and-wait,” Wyden wrote. He went on to write, “Increased monitoring is a necessary, but not sufficient response, to the deteriorating condition of the Hanford tanks.”