More efficient handling of nuke waste is urged

Benjamin Grove

Friday, Dec. 17, 2004 | 8:59 a.m.

WASHINGTON -- Yucca Mountain managers need a better overall plan for handling high-level nuclear waste after it is hauled to the proposed repository, a project watchdog panel said.

The nation's most highly radioactive waste would be shipped from sites nationwide to Yucca for permanent storage under the Energy Department plan.

But the department does not have an "integrated" plan to efficiently deal with the waste when it arrives, Nuclear Waste Technical Review Board chairman John Garrick said in an interview. The board was commissioned by Congress to conduct technical oversight of Yucca.

Nuclear reactor waste generates heat as it decays, which may affect the tunnel rock inside Yucca. Some waste likely would be stored temporarily at the Yucca surface facility after it arrives as workers sort it based on when it was removed from its reactor, and how long it has been cooling in pools or dry cask containers. Workers will sort waste and place it in the tunnels based on how "hot' it is.

It's also possible that once the waste arrives at Yucca it will have to be stored temporarily in an on-site storage container, then re-loaded into a permanent storage container, Garrick said.

Under current plans, highly radioactive waste could be handled up to four times before it is finally sealed away forever inside Yucca's underground tunnels, Garrick noted in a Nov. 30 letter to the Energy Department's Yucca director Margaret Chu.

The Energy Department needs a plan to minimize waste handling and to devise a more efficient system, the Garrick wrote.

"We are concerned that right now their act isn't quite together on integrated systems," Garrick said.

More analysis is needed to "identify possible safety and operational concerns, and optimize the system," Garrick's letter said.

Energy Department spokesman Allen Benson said department officials were reviewing the letter and offered no response to it.

On an unrelated subject, the letter also cautioned the department to further consider the effects of molten rock, or magma, on the waste containers. Yucca critics have long said that volcanic activity was a possible threat, but the risk has been dismissed by many project supporters as an extremely remote possibility.

An early study conducted by the Electric Power Research Institute indicated that samples of a nickel-based metal called Alloy 22 -- a material likely to be used for waste containers -- held up well when exposed to magma.

But the chemical compositions of magma at Yucca would vary widely and more research is needed to know if the waste canisters could survive a flow of molten rock in the Yucca tunnels, the board noted in its letter.