US Centrus Energy Corp (formerly known as USEC) announced on 2 October that it had been awarded a $15 million work authorisation by the US Department of Energy (DOE) for decontamination and decommissioning (D&D) to prepare the K-1600 facility in Oak Ridge, Tennessee, for demolition. Centrus has leased K-1600 - the former K-25 site - from the DOE since 2002 to test and demonstrate its uranium enrichment technology. The company has also been conducting centrifuge manufacturing, engineering and design at its own nearby Technology and Manufacturing Centre (TMC) in south Oak Ridge, at the former Boeing plant.
K-25 and other Oak Ridge sites were built during World War II as part of the Manhattan Project to build atomic weapons. The K-25 “footprint,” the slab area where the building used to be, is part of the Manhattan Project National Historical Park, which also includes Oak Ridge; Hanford, Washington; and Los Alamos, New Mexico. Efforts are under way to preserve the history of K-25 with a history centre, equipment building, and viewing tower.
The D&D work will continue until 30 September 2019. It will involve removing and disposing of equipment and materials to make K-1600 non-radiologically contaminated and non-possessing (i.e. unclassified), a press release said. DOE will then transfer K-1600 to a contractor for demolition. It is one of the last remaining “legacy structures” on the 2200-acre site of the World War II-era K-25 uranium enrichment plant, now known as the East Tennessee Technology Park (ETTP), the press release said. Many other buildings have been demolished, including the five large gaseous diffusion buildings once used to enrich uranium and ETTP is now being converted into a large industrial park.
The K-1600 D&D is part of a wider DOE effort by to clean up the site for commercial and industrial re-use, the press release said. The Lead Centrifuge Facility (LCF) at the Portsmouth Gaseous Diffusion Plant (GDP) in Piketon, which started operations in August 2006, was intended to demonstrate the gas centrifuge design and equipment for use in the planned American Centrifuge Plant.
Centrus completed a three-year operation of the LCF in 2016, demonstrating the long-term performance and reliability of the machines.
In March that year, the company notified the Nuclear Regulatory Commission (NRC) of its decision to permanently close the facility after DOE announced it would no longer fund operations. DOE announced in that it had exercised its option to extend its contract with Fluor-BWXT Portsmouth for D&D of the GDP for 30 months beyond the 30 September expiration date of the initial contract, which began in March 2011.
Derryberry said the unit was considered successful when it was shut down after meeting performance requirements. Since then, Centrus has continued to improve the technology, seeking to reduce costs and increase reliability, he added, but noted that currently the commercial market will not support a new enrichment plant. However, although the American Centrifuge Plant has not been built, DOE still wants to develop a domestic source of enriched uranium, and Centrus is working with Oak Ridge National Laboratory on that project.
“Centrus continues to discuss with DOE the additional development, testing, and demonstration work on US uranium enrichment technology for future use by the US government for national security purposes,” the press release said. Centrus currently has two primary enriched uranium supply contracts - one with Russia’s Techsnabexport (Tenex) and the other with France’s Orano. There is also surplus inventory from the Paducah gaseous diffusion plant in Kentucky, which was shut down in 2013. Centrus also gets enriched uranium by purchasing inventories that become available on the market.