The report by MRW & Associates, an Oakland-based consulting firm that specializes in power market issues, said the U.S. Department of Energy was supposed to open the Yucca Mountain storage facility in Nevada by 1998.
"However, nearly 10 years after the deadline, a repository at Yucca Mountain is still more than a decade away from being opened, and the opening date continues to slip," the report states.
The Department of Energy said last year the storage site could be opened as early as March 2017 but that a more realistic date was September 2020, according to the MRW report. Earlier this year, the department pushed those predictions back another year.
A California law passed in 1976 prohibits construction of nuclear plants until the Energy Commission concludes that the federal government has found a proven way to store or reprocess spent nuclear plant fuel.
The MRW report comes as the commission opened two days of hearings Monday on the status of nuclear power. Information from the hearings will be used to prepare a report to the governor and Legislature on how to address the state's energy needs.
The state currently has two operating nuclear plants, San Onofre and Diablo Canyon. California utilities also own 27 percent of the Palo Verde Nuclear Generating Station in Arizona.
Nuclear plants supplied nearly 13 percent of the state's electricity last year, and supporters tout expansion of nuclear power as a way to reduce greenhouse gas emissions and combat global warming.
But a long-term method to deal with the waste from nuclear plants remains elusive.
California has more than 2,400 tons of radioactive waste stored at active and decommissioned nuclear plants, and the spent fuel continues to accumulate, said Robert Weisenmiller, executive vice president of MRW.
Eric Knox, an official with the Department of Energy's Office of Civilian Radioactive Waste Management, said he remains optimistic that Yucca Mountain will be opened despite the delays.
"I have never felt better about the future prospects of our success," he told commission members.
He said the department expects to ask the Nuclear Regulatory Commission in June 2008 to grant it a license to operate Yucca Mountain. The Environmental Protection Agency, however, has not drafted standards that the commission will impose on operations at the site.
The department also needs Congress to approve legislation giving it ownership of Yucca Mountain, although construction of the storage facility could begin before that transfer takes place, Knox said.
Opponents say Yucca Mountain has serious environmental problems.
The area around the site, about 100 miles northwest of Las Vegas, is laced with earthquake faults. It also is near at least one potentially active volcano, said Allison Macfarlane, associate professor of environmental science and policy at Virginia's George Mason University.
The groundwater at Yucca Mountain also is highly corrosive, said Robert Loux, executive director of Nevada's Agency for Nuclear Projects. He predicted it would eat through waste containers stored there.
"That's why I believe the site is unlicensable," he said.
After Monday's testimony, California Energy Commission member John Geesman said he had not heard anything to contradict the commission's 2005 finding that the federal government hadn't met the requirements of the 1976 law.
Even if the department gets a license to operate Yucca Mountain, the project faces the likelihood of court challenges, he said.
"We should get ready to maintain spent fuel waste at the reactor site in dry cast storage for a very long time; decades," he added in an interview.
The MRW report also downplayed the possibility of reprocessing nuclear waste for reuse. It said several experts and the Energy Commission had concluded it was not economical and that it raised the possibility of nuclear weapon proliferation.
But a Maryland company that provides uranium and other services for nuclear power plants said reprocessing has been used successfully in Europe.
It would take 10 to 15 years to build a recycling facility in the United States, although nuclear waste could be shipped overseas for reprocessing, said Alan Hanson, an executive vice president for the company, Areva NC Inc.