The U.S. Department of Energy wants ideas about how more than 700,000 tons of depleted uranium being stored at atomic fuel plants in Ohio and Kentucky can be converted into more stable, environmentally friendly forms.

The waste has been accumulating since the 1950s at the former federal atomic fuel plant at Piketon, Ohio, 65 miles south of Columbus, and at a former federal plant at Paducah, Ky.

Fuel for nuclear-powered generators is manufactured at the plants, which now are operated by the privately held United States Enrichment Corp.

The waste, contained in 16,000 rusting and sometimes leaky 14-ton steel cylinders at Piketon and 36,000 cylinders at Paducah, has been a headache for federal and state environmental officials.

“We want the stuff converted” to a more stable form, said Graham Mitchell of the Ohio EPA. “It’s a huge waste-material management problem. It’s been setting out there for up to 50 years.”

The conversion could also provide employment for people in a part of Ohio lacking jobs, but that would be years from now if the project goes forward.

About 4,683 cylinders of material will be brought to the Piketon plant from Energy Department sites at Oak Ridge, Tenn., boosting the material eventually slated for Piketon to more than 20,000 cylinders containing 250,000 tons of depleted fuel.

The material is depleted uranium hexafluoride, normally a crystalline material but which is converted to hydrogen fluoride gas and a compound of uranium, fluoride and oxygen when it contacts air.

Friday, the Department of Energy circulated a draft proposal asking for ideas on how contractors would handle the conversion process. The idea is to convert the uranium hexafluoride into uranium oxide and/or uranium metal, both of which are more stable and not so prone to accidents.

No matter the final form, the plants required to do the work would be expensive — on the order of $200 million each.

Energy Department officials also hope to prove that the uranium hexafluoride isn’t waste, but a material usable in industrial processes and
the military.

However, there would have to be far more demand than the most frequently mentioned uses — armor for tanks and fabrication of casks for the storage of high-level waste at the government’s Yucca Mountain site.

Plans are for the department to seek bids in early 2000 after the agency has completed its request for proposals. Details about how much material may eventually be sold and how much will remain in storage are undecided.

Also not known are the sizes of the plants and the number of people who would be employed, although the number of workers is expected to be about 70 at each facility, said Dale Jackson, director of the department’s uranium management division.

Contractors might choose to build the plants themselves and get a jump on competitors for the anticipated $2 billion job of converting the material, Jackson said.

If private contractors are not willing to build and operate the plants, the government will have to build the plants, he said.

Authorization for the plants was part of the act privatizing the U.S. Enrichment Corp., the federal corporation formed to take over the atomic fuel operation from the Energy Department.

The act called for the corporation to set aside $373 million for conversion of the company’s waste so that more waste would not pile atop the existing waste.

However, the company’s waste has been accumulating only since July 1, 1993, and represents a fraction of the total uranium hexafluoride at the sites. The vast majority of the material is the responsibility of the Energy Department.

Conversion of that material will require appropriations from Congress, Jackson said.

“The impetus is to get it done as quickly as possible,”he said.

That might mean a decade or it might mean several decades, he said.