Hanford experts are wondering what to do with 12 buried barrels holding plutonium 238.

They are buried in a 200 West Area trench that holds a large number of drums of transuranic and low-level radioactive wastes.

Fluor Hanford recently began removing dirt and barrels from the trench and expects to reach the 12 drums of plutonium 238 next spring or summer, said Mark French, the Department of Energy's transuranic waste disposal project director.

On Nov. 7, the Defense Nuclear Facilities Safety Board wrote DOE to note that it identified the 12 barrels as a problem in June 2002, but has not received information yet from DOE about how it plans to deal with the drums.

The board wants an answer by early February.

"We have the same concerns as the defense board in dealing with those drums," French said.

DOE hasn't replied because Hanford just began removing barrels of wastes from 200 West Area trenches in late October, French said. Also, Hanford has not figured out what to do with those barrels, he said.

They contain plutonium 238 and plutonium 239 shipped to Hanford from Savannah River in the 1960s for experiments at Pacific Northwest National Laboratory.

Afterward, the plutonium was placed in cans, which were put inside barrels, which were buried in the 200 West Area along with thousands of other drums of wastes.

The plutonium 238 presents a headache, French said, because it emits much more radiation and more heat than plutonium 239, which Hanford normally deals with. That increases the chance of damage to the barrels and danger to workers moving the drums. Also, if plutonium 238 reaches ground water, it moves faster through the soil than many other contaminants.

Although plutonium 238 is a transuranic substance, the concentrations in the barrels are much greater than can be legally accepted at a permanent underground transuranic waste site near Carlsbad, N.M.

And plutonium 238's extreme heat and radiation are hurdles to converting it into a safer form at Hanford's Plutonium Finishing Plant.

DOE and Fluor have to figure out how to dig up the barrels safely, inspect them for damage and repack them if needed, and where to dispose of them.

French said some questions might be answered by early February when DOE replies to the defense board.

However, he said, many questions will still need to be answered before DOE can settle on a plan to deal with the drums.

If no plan is ready by the time Hanford workers are ready to unearth the drums, they will be left buried. If that happens, workers will shift to removing barrels from other nearby trenches, he said.