Government scientists say studies support Yucca site

RENO, Nev. - Government scientists presented snippets of studies Wednesday suggesting that ground water movement, thermal activity and other geologic conditions are conducive to storing radioactive waste beneath the Southern Nevada desert for thousands of years.

But Robert A. Levich, a geologist with the U.S. Department of Energy's Yucca Mountain Project, reiterated the federal government's position that a repository would not be built 90 miles northwest of Las Vegas unless science proves it can be done safely.

''We will not build a repository at a fatally flawed site,'' Levich said during a briefing on four of 31 papers dealing with Yucca Mountain that will be detailed Thursday at the Geological Society of America's annual convention being held here.

''The scientists who've been working on Yucca Mountain have not been working to prove it is a good site'' or ''to prove something is good that is not good,'' Levich said.

Bo Bodvarsson, a scientist with the Lawrence Berkeley National Laboratory in Berkeley, Calif., has been studying whether heat from the radioactive material and resulting geothermal activity could cause corrosion of casks designed to hold the waste for tens of thousands of years.

Bodvarsson said his study suggests the high temperature of the rocks beneath the mountain would turn any water to steam, preventing it from condensing and pooling near ''drifts'' where casks would be stored.

''We believe that our studies ... will show that there will be absolutely no water getting into the drifts,'' he said.

Other scientists cited studies on ancient caves, the movement of test materials through similar rock types and groundwater flows as supporting Yucca Mountain's suitability.

Yucca Mountain is the only site being studied for a repository for 77,000 tons of spent fuel from nuclear power plants and defense waste around the country.

Nevada officials and the state's congressional delegation have been battling the federal government for years over the project and question the integrity of studies conducted for the DOE.

On Tuesday, an independent scientist from Bucknell University in Lewisburg, Pa., said she has discovered evidence in an earthquake fault at Yucca Mountain in which minerals were deposited by a significant amount of water.

The finding could contradict federal claims that any ground water in Yucca Mountain within the past million years was deposited by rain and not by hot water rising from deep beneath the mountain, the Las Vegas Sun reported.

If such flooding did occur, it raises the possibility of it reoccurring and causing corrosion.

That report contradicted another released earlier Tuesday by UNLV researchers that said Yucca Mountain was dry enough for a repository.