The administration wants to store about 132,000 tons of nuclear waste in Yucca Mountain, an underground waste dump about 90 miles northwest of Las Vegas. But the project is still plagued by scientific foul-ups and political stonewalling. Congress approved Yucca Mountain as the site for the nation's radioactive waste in 2002, but the Energy Department has yet to publish a schedule for opening it.

Energy Department officials told Domenici's panel that they plan to unveil a schedule for sending a building application to the Nuclear Regulatory Commission this summer.

But Domenici said the Bush administration's legislative proposal to speed up Yucca Mountain "has a big vacuum in it" because it does not address what will happen to the waste while Yucca Mountain makes its way through the many regulatory and legal steps that remain.

Spent fuel from the nation's nuclear plants -- which supply about 20 percent of US electricity -- is piling up, with over 50,000 tons of it stored at over 120 temporary locations in 39 states.

Domenici also said he favors a legislative plan to recycle nuclear waste instead of putting fuel rods from nuclear reactors into Yucca Mountain.

"I think we're going to have to put recycling into the legislative process that involves Yucca Mountain," Domenici told reporters. "I think I'm telling you that everything is delayed a long time."

Domenici opposes storage of spent fuel rods because only about 5 percent of their available energy is spent when they are removed, his spokeswoman said.

The Nuclear Energy Institute, the industry's lobbying group, said the government should meet its obligation to store the industry's waste.

Some nuclear operators have sued the Energy Department for failing to meet its obligation to begin accepting waste in 1998, and liability will be up to US$3 billion through 2010 for failing to open Yucca Mountain on schedule, according to Justice Department estimates.

Paul Golan, acting director of the Energy Department's Office of Civilian Radioactive Waste Management, said the administration lacks the authority to proceed with an interim storage plan while it waits for Yucca to get built.

Meanwhile, the Energy Department has already begun a process to select a second repository as required by law, even though Yucca Mountain is far from complete. Golan said he assembled a selection team Monday, which will make an initial report in July.

Sen. Jim Bunning, Kentucky Republican, said Yucca Mountain will be virtually full from the waste that is waiting to be shipped there.