Environment

Top physicist calls for caution regarding Yucca Mountain
“Yucca Mountain has the biggest problems it has ever had right now. The Department of Energy is committed to getting a license application into the Nuclear Regulatory Commission by the end of this year. This is a head-on train wreck. If they put in a license application, it’s going to be a lousy job because they don’t have the science to put in a good one.”

Those are the words of Paul Craig. He’s a physicist by training and a professor emeritus of engineering at UC Davis. While those bona fides are enough, he has one credential that puts him above most other people when discussing Yucca Mountain. He was a member of the Nuclear Waste Technical Review Board—the top board for the study of Yucca Mountain—from 1996 until January 2004.

Some question those credentials. The Department of Energy spokesman Allen Benson, for example.

“He’s a former member of the Nuclear Waste Technical Review Board who appears to be on some kind of crusade,” Benson says. “I don’t believe he’s a metallurgist, so I’m curious as to how he can talk about the metal issue.”

Membership to the review board requires a presidential appointment. Craig was appointed by President Clinton. Clinton got Craig’s name from the National Academy of Sciences. It was a cake deal, particularly for Craig who’s been interested in energy matters from technical and policy standpoints.

But in January, Craig did the unexpected. He quit the 11-member commission in part to protest the actions of the Department of Energy. Mostly, though, he quit because it was time to start speaking his mind about the science behind the plan to store 77,000 tons of high-level nuclear waste at Yucca Mountain, about 90 miles northwest of Las Vegas.

Craig is particularly worried about the casks that are supposed to contain nuclear waste for hundreds of thousands of years.

A November report by the NWTRB, which can be found at www.nwtrb.gov/reports/2003ltr.pdf, suggests that localized corrosion of the metal casks is likely.

Craig’s assessment is harsher.

“If you operate under the conditions that you propose to operate at, these canisters are going to corrode, and radioactivity will be released into the environment,” he said.

Put in simplest terms, the DOE hopes to store highly radioactive waste in special metal canisters in Yucca Mountain. After the canisters are placed in tunnels and the mountain is sealed, temperatures will begin to rise to hundreds of degrees. That process will last several hundred years. It’s when the temperatures begin to cool that the issue that’s got Craig spooked will arise. Yucca Mountain is water permeable.

While the waste is hot, water that drips onto the casks will evaporate as steam. However, when the waste cools off, the water will condense on the casks. As water collects on metal, even on metal as high-tech as Alloy-22, the skin of the casks, metal begins to corrode. Faster when the salts in the rock of Yucca Mountain are factored in. And eventually, though maybe not for 1,000 years, radioactivity may leak into the ground and into the nearby water aquifers.

“If they were to design it so it never got hot, they might very well be able to do a good design,” he says. “But to do that design, they need scientific data about the details of the mountain, which they’re not collecting.”

Benson, the Energy Department spokesman, says Craig is premature in his fears and wrong in his facts. The Yucca Mountain design is ongoing, and even if this design isn’t the best, the design is improving.

“We are working with the Nuclear Waste Technical Review Board, and we are working with the Nuclear Regulatory Commission to resolve any concerns that they have raised,” Benson says. “This is an iterative process. You design something, you see how it works, and you talk to experts in the area and then you go back and forth until you come up with the best possible design.”