The Department of Energy’s projected cost for cleaning up the radioactive waste legacy of the Cold War and Manhattan Project continues to mount, the Government Accountability Office (GAO) said in a report made public this week.
“As of May 2025, EM [DOE’s Office of Environmental Management] estimated that the remaining cleanup work at all its sites would cost more than half a trillion dollars,” GAO said in its latest report on the office.
There are currently 15 Environmental Management cleanup sites across the country and EM estimates the remaining work could drag on until 2122, according to the report.
The total estimated costs for Environmental Management’s biggest capital asset projects, which have defined start and end dates, increased by more than $2 billion between 2022 and 2025, according to the GAO report. 2022 was the last time GAO issued a detailed report on Office of Environmental Management costs.
Examples of big capital projects include construction of the Waste Treatment Plant at the Hanford Site in Washington state and the new underground ventilation system at the Waste Isolation Pilot Plant (WIPP) in New Mexico, GAO said.
Meanwhile, the cost estimates for Environmental Management’s most expensive operations increased by about $75 billion since GAO last reported in 2022. Examples of the biggest operations include liquid tank waste stabilization and disposal for Hanford as well as the Savannah River Site in South Carolina.
“EM has seen cost increases and schedule delays due to multiple factors, and the office struggles to maintain complete documentation and reconcile data discrepancies,” GAO said.
“Even if EM improves the completeness and consistency of information on its projects and activities, its cost and schedule estimates may still reflect significant uncertainty,” GAO said in the report. “EM officials from several sites told GAO that final cleanup remedies at their sites still need to be determined, which may increase costs and schedules.”
The March GAO was issued to House and Senate Armed Services and Appropriations Committees. The Environmental Management audit is the second report GAO rolled out in the past couple of weeks on the weapons complex. It published a report on DOE’s National Nuclear Security Administration on Feb. 26.
In comments included with the GAO EM report, DOE’s Assistant Secretary for Environmental Management Tim Walsh, said the cleanup office hopes to enact GAO’s two recommendations by Sept. 30.
This includes updating EM operating procedures to ensure the latest data reports are entered into DOE’s Project Assessment and Reporting System. It also includes improving coordination with the cleanup sites and contractors.