The Nuclear Regulatory Commission questioned Westinghouse Electric Co. officials Wednesday about nuclear material missing from its fuel-making plant in Columbia, S.C.
An NRC enforcement meeting in Atlanta addressed the loss of 4.5 ounces of powdered uranium hexafluoride, also known as UF6. Westinghouse workers discovered on Feb. 11 that three five-gallon cans containing 16 sample vials of the material were unaccounted for.
Westinghouse workers and an outside consultant made visual and radioactive searches of the fuel plant, a nearby landfill and facilities for scrap metal recycling and metal shredding. No signs of the material were found.
Vaughn Gilbert, spokesman for Monroeville-based Westinghouse, said the company believes the cans have been covered over in an Elgin, S.C., landfill, but that the materials are too weak and small in volume to pose an environmental threat that would merit unearthing them. Nevertheless, he said, “It’s a situation that should not have happened.”
“We take this type of thing very seriously,” Gilbert said. “We have safeguards in place that we are continuing to evaluate and strengthen to make sure nothing like this happens again.”
The Union of Concerned Scientists, however, raised concerns about the possible health risk if the UF6 is exposed to water or even humid air. Under those conditions, toxic hydrofluoric acid is created that can be deadly in large quantities. In 1986, a worker at a nuclear fuels plant in Oklahoma died and five others were hospitalized when nearly 15 tons of UF6 spewed from a ruptured tank.
NRC spokesman Ken Clark said the amount of missing UF6 in this instance is far too small to cause any major or permanent health risk, either from radioactivity or if transformed into inhalable acid. Nor is it enough to be useful for nuclear weaponry, he added. The missing fuel would emit radiation no greater than the amount experienced by a passenger on a one-way flight between New York and London from altitude-related cosmic radiation.
The NRC is contemplating three violations of fuel-handling rules. A decision on Westinghouse’s possible culpability and fines is expected within 30 days.