The U.S. Energy Department is seeking comments on options for disposal of material generated from conversion of depleted uranium hexafluoride (DUF6) at the Portsmouth Site in Ohio and the Paducah Site in Kentucky.
The DOE Office of Environmental Management said in a Dec. 28 Federal Register notice it has issued a draft supplemental environmental impact statement on disposal options for the material being generated from the DUF6 work at the two former gaseous diffusion plants.
In the draft supplemental EIS, the Energy Department has said the resulting uranium oxide material could be taken to one of three low-level radioactive waste disposal centers: DOE’s Nevada National Security Site (NNSS) in Nye County, Nev.; the EnergySolutions facility in Clive, Utah; and the Waste Control Specialists (WCS) site in Andrews County, Texas.
The document suggested the risk of serious radiation or chemical contamination for workers with maximum exposure, or from potential accidents that might occur along the way, was not high. For example, the risk of latent deaths from cancer is less than one for 18 years of shipping all the material from Portsmouth to Utah, the document said.
Comments are due by Feb. 11.
Mid-America Conversion Services, a vendor team comprised of Atkins, Westinghouse, and Fluor, has a five-year, $319 million contract through January 2022 to convert the inventory of DUF6 into a more stable uranium oxide form for storage and eventual disposal. It also sells a byproduct, aqueous hydrofluoric acid, for reuse.
The Energy Department manages about 700,000 metric tons (759,000 tons) of DUF6 at the two sites, resulting from former uranium enrichment for nuclear weapons. All DUF6 cylinders previously at DOE’s East Tennessee Technology Park (ETTP) at the Oak Ridge Site have been shipped to Portsmouth for conversion.
In June 2004, DOE issued final environmental impact statements on construction and operation of facilities to convert the DUF6 to depleted uranium oxide. This latest DUF6 document builds upon the 2004 EIS reports.
As of last spring, Portsmouth and Paducah had converted 61,696 metric tons of DUF6 since they began operations in 2010 and 2011, respectively, according to DOE.
In the current supplemental draft, DOE turns its attention to plans of disposal for the resulting material. It does not discuss the process or timeline for eventual disposal off-site.
The Energy Department is holding web-based public hearings in January to field comments on the draft environmental plan. The web sessions are set for 2 p.m. to 4 p.m. ET Jan. 22; 4 p.m. to 6 p.m. Jan. 23, and 7 p.m. until 9 p.m. on Jan. 24. Comments gleaned from these events will be weighed as DOE prepares its final EIS supplement.
Interested parties can access the public hearings by phone at 1-415-527-5035 and use access code: 988230782#. Anyone who wants to speak can sign up before each meeting by submitting a request to [email protected]. Details on accessing the Webex broadcast can be found in the Federal Register notice.
Comments on the draft supplemental EIS can be sent to [email protected].
Most of what would be shipped to the eventual disposal sites by truck or rail would be depleted triuranium octaoxide (U3O8), along with emptied cylinders and a small amount of calcium fluoride (CAF2).
Portsmouth and Paducah respectively produce 11,800 tons and 15,800 tons annually of depleted uranium oxide material, according to the draft supplement. By comparison, the two sites together will generate less than 50 tons annually of the calcium fluoride material. It is assumed the Portsmouth conversion facility will operate for 18 years and the Paducah plant for 25 years, according to the draft.
It would take about 18 years to ship Portsmouth material to either EnergySolutions or the Nevada site, according to the draft document. would result in less than 1 latent cancer fatality from shipments to either location, DOE said. The document indicates DOE is prepared to select either site as the disposal location for the conversion material from Portsmouth and Paducah.
The outlook for WCS appears less certain, the document suggests. Waste Control Specialists could be “a reasonable alternative for disposal of the DOE depleted uranium oxide conversion product in the future,” it says.
“WCS is interested in disposal of the depleted uranium and cylinders from Portsmouth and Paducah” said WCS President and Chief Operating Officer David Carlson in an email Thursday. “Our license has allowed for disposal of DU since 2014, and we currently dispose of DU at the WCS facility,” he added.
The current license, however, does not allow WCS to take uranium hexafluoride material, said Texas Commission on Environmental Quality spokesman Brian McGovern.
EnergySolutions “has confirmed its ability to accept the annual amount of depleted uranium oxide conversion product that will be produced by the two DUF6 conversion facilities for the next 25 years,” and it would be a small portion of the company’s throughput at the Utah facility, according to the draft.
