The Department of Energy is hoping to expand the capacity of the $90 billion Yucca Mountain nuclear waste repository in Nevada—a facility that President-elect Barack Obama has consistently said he opposes—instead of building a second repository, The New York Times reported last week.

Edward F. Sproat III, director of the DOE’s Office of Civilian Radioactive Waste Management, said at a conference hosted by the Center for Strategic and International Studies in Washington that the amount of spent fuel in the U.S. would reach the 77,000-ton limit of the repository just two years from now. It was therefore necessary to expand Yucca Mountain’s capacity or build a second storage site. But given that the process to open one repository had been slow and expensive, this would not be a good time to start looking for another, he said.

Sproat said he would deliver a report to Congress soon outlining those choices—as well as an option not to “do anything and let this whole thing just sit for another 10 to 20 years and see what happens,” the Associated Press said.

Sproat’s announcement comes at a time of great uncertainty for the project. With the new administration comes a likely change of top Energy Department officials. The repository’s price—$19 billion more than last year’s estimate—and mounting federal debt also make the undertaking costly.

The government promised utility companies that the facility would begin accepting waste in 1998, and it is currently accepting payments of $0.10 per kWh. The repository is now scheduled to open by 2020 at the earliest. The New York Times estimated that, as a result of the delay, the government could owe the utilities commercial damages of $11 billion or more.

The option for a second repository stems from the early 1980s, when the DOE was originally assessing sites in which to bury waste from reactors and the nuclear weapons program. The DOE had wanted to build one repository in the West and one in the East and had listed dozens of sites in seven states. Congress had directed the DOE to focus on Yucca Mountain and set that waste repository’s limit at 70,000 tons.

The DOE had last year announced it was looking to double the size of the repository to a capacity of 135,000 tons.

“We do think there is room for additional storage at Yucca. How much, we’re not clear on,” Sproat told reporters last week.

Sources: The New York Times, AP, Las Vegas Review-Journal