Vermont Yankee owner Entergy Nuclear won permission Friday from the state to build a second pad on which to store concrete-encased radioactive nuclear waste at the closed plant.
The Public Service Board allowed the second pad on the grounds that it will have “no undue adverse effects on the environment” and will promote the state’s general good by hastening the transfer of spent nuclear fuel from the pools in which it now sits.
Entergy anticipates keeping the storage casks on the pads until as late as 2052, by which time it is hoped the federal government will have built a permanent storage facility for the country’s nuclear waste.
Until then, state officials say, the waste is better off stored inside concrete dry casks than submerged in cooling pools.
An existing concrete pad holds 13 casks and can accommodate 36, but the plant in Vernon is thought to contain enough spent fuel to require 58 casks in total.
Storing the waste in 13-ton concrete casks will eliminate the need to monitor the pools in which it’s currently held, said Public Service Commissioner Chris Recchia on Monday. The pools require human intervention to keep them operating in case of certain emergencies, Recchia said, and their moving parts introduce potential sources of failure that dry casks lack.
“I think this will help alleviate any remaining issues with the fuel, in terms of management,” Recchia said.
Moving the waste into casks also is a step toward preparing the fuel for permanent disposal once the federal government secures a suitable location, he said.
The transfer into concrete casks also speeds the process of making the Vermont Yankee site radiologically inert again, Recchia said. The plant stopped producing power at the end of 2014.
Entergy committed publicly to have the spent fuel moved from storage pools into casks by the year 2020, Recchia said.
Vermont Yankee spokesman Marty Cohn said the PSB order comes in time for his company to meet that deadline.
Entergy will put up about $143 million to build the pad and purchase and fill the casks, Cohn said. The federal government will then reimburse the company.
The company’s upfront contribution will conserve money already in the Vermont Yankee decommissioning trust fund. Some people are concerned that any withdrawal from the fund will further delay the eventual cleanup of the plant, which isn’t set to start until the fund has enough money.
Entergy has earmarked an additional $225 million to store the casks until as late as 2052, Cohn said; that money will be withdrawn as needed from the cleanup fund.
The fuel is to be stored for decades on the site because the federal government failed to build the planned Yucca Mountain spent fuel repository in Nevada. Nuclear plant operators have for years paid a portion of their proceeds toward such a site. Since none exists, the Department of Energy will reimburse Entergy for both the cost of interring the material in casks and for storage costs.
Opponents have 10 days from the PSB order’s filing date of June 17 to ask the board to reconsider, Cohn said.
Barring such a request, Vermont Yankee will have secured all the necessary permits to begin transferring spent fuel from the storage pools into dry casks, Cohn said.
Cohn said he doesn’t expect further obstacles to the transfer and that he and the company are very pleased with the board’s order.