The Government Accountability Office is recommending that Congress clarify the Department of Energy’s legal authority to sell depleted uranium hexafluoride (DUF6) left over from uranium enrichment operations at the department’s Portsmouth Site in Ohio and the Paducah Site in Kentucky.
The DOE estimates that it could cost at least $7.2 billion to convert its inventory of DUF6 into more stable chemical forms and dispose of it off-site. But if the DOE can transfer portions of its DUF6 inventory—such as by selling some to a private company—it could save billions, according to the GAO.
The GAO findings are contained in its report, “Nuclear Waste Cleanup: DOE’s Efforts to Manage Depleted Uranium Would Benefit from Clearer Legal Authorities,” published on July 27. The DOE has not issued comment on the report as of this writing.
The findings: The DOE’s Office of Environmental Management (EM) used the COVID-19 shutdown to perform maintenance and modifications at the two DUF6 conversion facilities at Portsmouth and Paducah. These facilities convert DUF6 into two primary products: depleted uranium oxide and hydrofluoric acid.
According to the report, the agency spent about $47.4 million on modifications to improve the facilities’ efficiency. EM has not fully assessed the impact of this shutdown on the conversion mission, but officials have stated that they were developing new cost and schedule estimates for the facilities that will be finalized in 2022, the GAO said. Conversion operations restarted at the Paducah facility in November 2021, and EM officials told the GAO that operations restarted at the Portsmouth facility in July 2022.
Ownership: EM has three agreements to reserve nearly 30,000 cylinders of DUF6 (about 44 percent of the inventory) for use by other entities. If the agreements are finalized, the agency may not need to convert all its DUF6 and could reduce operations of the conversion facilities by roughly 30 years, potentially saving over $2 billion in operations costs, according to the GAO report.
EM has two agreements to transfer ownership of nearly 5,500 cylinders to the National Nuclear Security Administration for two separate programs, but the plans and timing of one agreement are uncertain, noted the GAO. EM has also reserved over 24,000 cylinders to sell to a private company. However, the GAO said that the DOE’s authority to sell depleted uranium is doubtful, as it appears to be inconsistent with the 1996 legislation governing DOE uranium disposition.
Disposal: EM has identified options for disposing of depleted uranium oxide, but plans have not been finalized, according to the GAO. EM has determined that three waste disposal sites may be suitable for the depleted uranium oxide but, as of March 2022, only one is licensed to receive it. EM officials have noted that the agency has been waiting for funding before beginning the disposal process.
In addition, EM has directed its contractor to sell hydrofluoric acid to a private company and apply the proceeds of those sales to contract costs, the GAO said. EM has been able to keep and use the proceeds of the hydrofluoric acid sales under appropriations laws enacted from fiscal years 2011 through 2022.