LAS VEGAS — The Department of Energy is proposing doubling the size of a national nuclear waste repository it plans to build deep below an ancient volcanic ridge in the Nevada desert.

Citing ongoing production of waste at nuclear power plants around the nation, the Energy Department has revealed plans to entomb almost 150,000 tons of highly radioactive waste at Yucca Mountain, which at least one member of Utah's congressional delegation thinks is a bad idea.

"Given DOE's success so far with Yucca Mountain, I would suggest two times nothing is still nothing," said Rep. Chris Cannon, R-Utah. "We need safe nuclear power and the reprocessing that will allow its development."

Nevada's senators and a state official said Friday they doubted Congress would revise a law that caps the Yucca Mountain project at 77,000 tons of radioactive waste and will balk at a price tag that now tops $77 billion.

"If they think they are going to get more money for an irresponsible plan to ship nuclear waste across the country and into Nevada's back yard, they're dreaming," Democratic Majority Leader Harry Reid said.

Bob Loux, head of the Nevada Agency for Nuclear Projects and the state's chief anti-Yucca administrator, branded an environmental study outlining the proposal as "invalid and likely illegal."

He said it went beyond congressional authorization under the Nuclear Waste Policy Act of 1982 and sought exemptions from transportation regulations and hazardous waste laws.

Nevada has been fighting against the proposed nuclear repository for decades while the nuclear power industry has been waiting for the federal storage site for nuclear waste that was supposed to open in 1998 for same amount of time.

The federal storage site's delay prompted some utilities to create the Private Fuel Storage facility plan for a temporary storage facility at a Goshute Indian reservation about 45 miles outside of Salt Lake City.

Utah strongly opposed the idea, but the Nuclear Regulatory Commission granted the site a license. Decisions by the Bureau of Land Management last year took away transportation-route options for the site, which virtually killed the project, although its backers insist their fight is not over yet.

Cannon and the rest of the Utah congressional delegation joined with Nevada's congressmen on a bill in 2005 that would have kept waste onsite at nuclear power plants.

The release of the environmental study, which triggers a 90-day public comment period, came as the Energy Department ramps up efforts to meet a self-imposed June 30 deadline to submit an application to the Nuclear Regulatory Commission for a license to operate the repository in tunnels 1,000 feet below the desert surface.