WASHINGTON -- The Department of Energy on Wednesday expanded the role of government science laboratories at Yucca Mountain, continuing its reorganization of the nuclear waste repository project.

DOE designated Sandia National Laboratories as the lead agency to coordinate science and technical work for the Nevada repository, where the government wants to bury 77,000 tons of high level spent nuclear fuel.

Sandia has been involved in the Yucca Mountain program since its inception in the early 1980s, with cadres of scientists that have contributed to performance assessments, field and laboratory testing and quality assurance, according to the laboratories' Web site.

The new designation greatly expands the role of the Albuquerque-based institute, one of 14 government science facilities that support Energy Department activities nationwide.

Paul Golan, acting Yucca Mountain director, said increasing Sandia's role will improve the credibility of the Yucca project with scientists and federal regulators.

Golan said Sandia performed a similar role in coordinating research at the Waste Isolation Pilot Project in Carlsbad, N.M., a repository that began receiving transuranic nuclear waste for disposal in 1999.

"The independent, expert review that the scientists at Sandia will perform will help ensure that the technical and scientific basis for the Yucca Mountain repository is without question," Golan said.

It was not clear how the change might affect Yucca personnel, most of whom are based in Las Vegas.

The program employs about 100 federal workers in Nevada and about 2,000 others who work for contractors and national laboratories.

One source within the program said Sandia has been recruiting from among contractors who are facing potential layoffs.

Sandia National Laboratories employs about 60 people on the Yucca project.

The Energy Department announced several management and technical changes to the nuclear waste project over the past four months. The Yucca effort has missed self-imposed deadlines, and been confronted budget and legal challenges and fresh questioning by critics and outside reviewers.

A Nevada official who coordinates the state's official opposition to Yucca Mountain said he doubted Sandia's new role will spark the project.

"It's difficult to call Sandia independent, since they have had a major role to play in the program all along," said Bob Loux, director of the state Agency for Nuclear Projects. "In this case, the new boss is the same as the old boss. They've been part of the problem."

Sandia will take over project segments that focus on the placement of waste canisters within Yucca Mountain, the anticipated water flows through rock and the long-term environmental conditions that will gradually corrode the metal containers, officials said.

That work will be assumed from Bechtel SAIC, the project's management and operations contractor. Bechtel will now focus on developing above ground facilities where nuclear waste will be transferred from trucks or rail cars and positioned for burial.

Bechtel's initial five-year contract to manage the Yucca project expires in March. DOE and corporate officials are negotiating a new deal that will likely reflect the scaled back work scope, officials said.

Sen. Pete Domenici, R-N.M., chairman of the Senate Energy and Natural Resources Committee, applauded DOE's move.

"Sandia features some of the best scientists in the country and will be able to provide the Yucca Mountain Project with strong, centralized leadership," said Domenici, who is an active supporter of nuclear laboratories in New Mexico.

In another move reflecting greater reliance on the national labs, DOE said a building on the campus of the Idaho National Laboratory will be transferred to the Office of Civilian Radioactive Waste Management, which runs the Yucca Mountain project.

The TAN-607 building will be used to train nuclear fuel handlers for Yucca Mountain, the department said.

The 153,000-square-foot facility includes the nation's largest "hot shop," a shielded fuel-handling room where radioactive materials can be manipulated by radio-controlled cranes.

The announcement is the latest element in DOE's reorganization of Yucca Mountain. In the fall, officials announced they will redesign nuclear waste canisters and the above ground complex at the site to simplify fuel handling.

Last week, the department said Yucca Mountain management offices in Las Vegas and Washington were being reorganized.