WASHINGTON (AP) - The Energy Department says it could take two more years to determine how much recycled uranium - which contains traces of plutonium and other radioactive materials - passed through its nuclear facilities.

The agency released a preliminary review Thursday analyzing the flow of recycled uranium throughout the DOE sites between 1952 and 1999. The agency was unable to complete a final analysis due to "significant inconsistency and inherent uncertainty" in the data it gathered from 12 facilities at nine sites.

The investigation began in 1999, prompted by concerns that workers were unknowingly exposed to high levels of radiation at uranium enrichment plants in Paducah, Ky.; Piketon, Ohio; and Oak Ridge, Tenn.

The Energy Department used uranium in nuclear weapons and as fuel for reactors. The agency began recycling it in the early 1950s to reduce U.S. dependence on foreign uranium. The report said most Energy Department facilities stopped using recycled uranium in the late 1960s.

Recycled uranium is more harmful than mined uranium because it has been processed in a reactor, where it becomes contaminated with plutonium and neptunium.

Pete Dessaules, a team leader in DOE's Office of Plutonium, Uranium and Special Materials Inventory, said an overall assessment of the 12 facilities will help determine exactly how much recycled uranium was used over the years and how much may still be stored around the country.

However, the task is proving more difficult than expected, Dessaules said.

"The biggest challenge in completing the report is standardizing the definitions that were used in the site reports for recycled uranium," he said. "That may involve looking at millions of records."

According to DOE, recycled uranium was present at the following locations: Hanford, Wash.; Savannah River, S.C.; Idaho National Engineering and Environmental Lab, Idaho; Fernald, Ohio; West Valley, N.Y.; Weldon Springs, Mo.; RMI Inc., Ohio; the gaseous diffusion plants in Paducah, Piketon and Oak Ridge; the Y-12 Plant in Oak Ridge; and Rocky Flats, Colo.
---
On the Net:
DOE Report: http://tis.eh.doe.gov/legacy/