Figures released by the US Department of Energy (DOE) put the total cost of the Yucca Mountain repository – which includes research, construction and operation of the facility up to 2133 – at $96.2bn.

It is a steep rise from government estimates in 2001, which placed the cost at $57.5bn.

Officials in Washington said the new figures took account of a “substantial increase” in the amount of waste that will be shipped and stored at Yucca Mountain, and more than $16bn in inflation.

“This increased cost estimate is reasonable given inflation and the expected increase in the amount of spent nuclear fuel from existing reactors with license renewals,” said Edward “Ward” Sproat, director of the Office of Civilian Radioactive Waste Management.

Work on the Yucca Mountain project began in 1983, and has already cost the government about $13.5bn although it is not expected to open until after 2017.

Jim Riccio, nuclear policy analyst for Greenpeace, told edie: “These soaring costs are yet another reminder why the so called “nuclear renaissance” is really dead on arrival.

“Once touted as “too cheap to meter,” nuclear power and the cost of storing its atomic wastes has become too expensive to really matter.

“We need real solutions to our climate and energy problems that are fast and affordable and nuclear is neither.”

Kevin Kamps, from campaign group Beyond Nuclear, told edie: “To spend nearly $100bn on a hole in the ground guaranteed to massively leak deadly radioactivity into the drinking water supply over time would perhaps represent the biggest boondoggle yet of the Atomic Age.

“Sixty six years after Enrico Fermi first split the atom, we still don’t have a solution for the first cupful of high-level radioactive waste generated.”

The Nuclear Information and Resource Service (NIRS) called for the next administration to scrap Yucca Mountain.

Executive director Michael Mariotte told edie: “The Department of Energy finally has admitted what many observers already knew – the proposed Yucca Mountain nuclear waste dump would be the most expensive public works project in recorded history.

“Its cost is rising far higher than inflation, giving rise to the likelihood that the cost will increase far more before the facility could ever be completed.

“But even at nearly $100bn, the DOE cannot assure that the dump won’t leak, nor that it would even meet basic regulatory requirements.”

Throughout Yucca Mountain’s lifetime, the DOE estimates $54.8bn will be spent on construction, operation and decommissioning.

Another $19.5bn will be needed for transportation of nuclear waste, and more than $8bn for other costs.

Kate Martin

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