"There are going to be significant layoffs, several hundred. They're going to come in waves," he told Nevada's Legislative Committee on High-Level Radioactive Waste.

He later told the committee, led by state Sen. Mike McGinness, R-Fallon, that "at least 500 people would be removed from the program in the next several months, the majority in Nevada, some in New Mexico from Sandia (National) labs."

Of the "65 to 70" workers at the Yucca Mountain site, 100 miles northwest of Las Vegas, where a fence stretches across the entrance to the 25-foot-diameter tunnel that loops through the ridge, "basically all are going to be let go in the next 30 days," Sproat said.

Project spokesman Allen Benson said the tunnel's ventilation system was shut down in late December to save on "substantial" electrical bills. The cost at the site for electrical utilities, water and maintenance was $3 million last year.

Sproat said the program staffs some 2,400 full-time positions, but funding cutbacks by Congress of $108 million from the 2008 budget this late in the fiscal year have left him no choice but to pursue layoffs.

The Bush administration requested $494.5 million for the fiscal year that began on Oct. 1. Congress in December approved $386.5 million.

The lack of money probably will push back the Department of Energy's self-imposed June 30 license application deadline.

"I cannot stand behind the June 30, 2008, date," Sproat said about the deadline he had set for submitting a license application to the Nuclear Regulatory Commission. The submission would start what he expected to be at least a three-year review.

Sproat, a political appointee who predicts he will be fired in 12 months under a new administration, said he hopes the license application will be submitted under his watch.

"I am mildly optimistic, cautiously optimistic, that we will get a license application done, but I just don't know yet," he said.

Because of the cutbacks, complete construction of a rail line across east-central Nevada to deliver spent fuel will slip at least two years to 2016. As for construction to be under way in October 2009, "that's not going to happen," he said.

"The transportation piece is off the critical path. That's where we took the resources from" to make up for funding reductions, Sproat said.

And, receipt of the waste in 2017, as planned, isn't feasible.

"I would say the 2017 date is not achievable given the funding we've got," he said.

Bob Loux, executive director of Nevada's Nuclear Projects Agency and a critic of the Yucca Mountain Project, said outside the meeting that many of the layoffs will involve contractor personnel whose jobs would end anyway as their roles in the licensing work are completed.

Despite Sproat's direction to scale back aspects of the project, Nevada is not going to soften in its opposition, Loux said.

Late Tuesday, attorneys representing Nevada filed a 30-page appeal with the Nuclear Regulatory Commission that challenged a three-judge panel's rejection of Nevada's challenge that a database of 3.5 million licensing documents should not be certified as complete because crucial studies and safety reports are missing or are works in progress.

Without the documents, Nevada would have difficulty completing its review of the licensing data in the required six-month span, the state said.

"For these reasons, the commission should reverse the ... board's decision, strike DOE's certification and require that DOE may certify only when it has provided all of the core technical documents necessary to permit 'focused and meaningful contentions,'" the appeal said.

At the committee's meeting, Loux described a list of more than 25 concerns about the project, including DOE's repository design being only about 40 percent complete and the agency's failure to address fully the potential for terrorism and sabotage in transporting nuclear waste across the nation.

Contact reporter Keith Rogers at krogers@reviewjournal.com or (702) 383-0308.