The Department of Energy (DOE) must treat 54 million gallons of radioactive waste that it is holding in aging and leak-prone underground storage tanks in Hanford, Washington. DOE also has to develop plans every few years that model and evaluate different waste treatment options.
A Government Accountability Office (GAO) review has found that DOE has been working to find effective alternatives to deal with the waste—including speeding up treatment. However, the watchdog says the agency hasn’t fully evaluated the effects of the different options for treating tank waste and managing the tanks.
DOE’s plans cover the first phase of waste treatment and disposal at Hanford’s Low-Activity Waste (LAW) facility, including means of identifying and managing barriers to the plans’ implementation. The plans also identify potential cost and schedule effects to the tank waste management and treatment mission from such barriers, which DOE refers to as risks not addressed.
GAO found that while DOE is considering alternatives for treating the waste remaining after the first phase of waste treatment starts, it is not planning to evaluate certain alternatives that may shorten the treatment mission in its upcoming revision to its System Plan. This is a required planning document that models and evaluates different scenarios for tank waste management and treatment. DOE expects to issue a System Plan revision in December 2023. According to DOE officials, the revision will include an updated version of the current planning waste treatment scenario, along with several scenarios that include grouting LAW (i.e., immobilizing the waste in a concrete-like mixture) beginning by 2050. However, in other studies, DOE has been analyzing alternatives that would potentially enable it to begin grouting LAW much sooner, as early as 2027. Given the potential cost and schedule implications for managing tank waste associated with this and other expedited treatment alternatives analyzed in DOE studies, GAO believes the alternatives may merit inclusion in the next revision of the System Plan.
GAO therefore recommends that DOE consider, in consultation with the State of Washington, supplementing the scenarios in the next System Plan revision to include those that may allow expedited treatment of tank waste. DOE concurs with GAO’s recommendation and plans to implement it by December 31, 2025.