When the San Onofre Nuclear Generating Station officially ceased operations in 2013, most Americans moved on. But not in southern California, where activists and regulators are now at loggerheads over how to dismantle the site and where to store the spent nuclear fuel.
Simply, when the nuclear plants are generating electricity, the spent fuel is placed in “pools” where it is cooled for about five years. That is called “wet storage.” After it has cooled, that radioactive fuel is then transferred to “dry storage,” or in a concrete cask. At the San Onofre site, known as SONGS, one-third of the nuclear waste is now such dry cask while two-thirds remains in “wet storage.”
“We are determined to complete the safe decommissioning of San Onofre as expeditiously and cost efficiently as possible,” says Edison International’s Southern California Edison. “Our immediate goal is to safely move the power plant's used nuclear fuel, now cooling in pools, into dry cask storage as quickly and as carefully as we can until the government creates the long-term storage option that it has committed to implement.”
Last week, the California Coastal Commission voted unanimously to go ahead with dismantling SONGS, where 3.5 million pounds of used nuclear fuel is stored on site — a location easily visible from Interstate 5 and near the city of San Diego. The utility said that the process of moving the irradiated fuel from wet storage to dry storage will begin in 2020 and that it will take about 10 years.
The decommissioning will employ 600 people and the $4.4 billion cost will be paid mostly by using investment funds, although a third of it will come from the utility’s ratepayers. The decommissioning general contractors are Aecom and EnergySolutions
In July 2012, Southern California Edison shut down the SONGS units because tubes located in newly installed steam generators had prematurely eroded — items that had been installed in 2009. Specifically, Unit 2 was taken down for routine maintenance. Unit 3, meanwhile, was taken off line a few weeks later because of the leaking tubes. That is, excessive vibrations caused the erosion of the tubes and the small radiation leaks. The Nuclear Regulatory Commission said that the public was never in danger.
An international panel ordered Mitsubishi Heavy Industries to pay in March $125 million to the utility because it had supplied the defective steam generators.
“It’s a no-win,” Steve Padilla said, who is vice chair of the Coastal Commission, at last week’s hearing, per the San Diego Union Tribune. “If we fail to move this forward, we delay the decommissioning, we delay the ability to remediate the site ... I just want the public and region here today to know that all of us are holding our nose.”
Critics of the Coastal Commission’s current permit to store the used fuel on site say that the canisters to be used have a “thin wall” and that those containers cannot be inspected, repaired or maintained when they are in the ground. Such canisters can crack and release radiation, they say, adding that the better solution is to leave the spent fuel where it is — in cooling ponds, where they could remain for another 40 years. But if it has to be moved and placed in canisters, then it should be few hundred yards east and on higher ground. SCE posted a video on its website showing recent canister inspections and a method for canister repair.
The Citizens’ Oversight Projects wants the canisters to have a much thicker outer shell, enabling them to better avoid corrosion and deterioration.
Skeptics are also drawing attention to an incident that occurred last year in which a 50-ton canister had been wedged for 45 minutes. The canister, which held spent nuclear fuel, was getting moved from the wet storage pools to the dry storage area.
What is happening at SONGS is a microcosm of what is now taking place in the nuclear energy sector. That is, there are 96 nuclear generating units that hold 70,000 tons of radioactive nuclear waste on site. Besides Southern California Edison, Entergy Corp. and Dominion Energy are closing merchant nuclear plants that compete in the open market. PG&E Corp., meanwhile, will shut down its nuclear plant, Diablo Canyon, by 2025. All of them will face a predicament similar to that of Southern California Edison.
As for Southern California Edison, it would like to see the spent fuel get transferred to an interim storage facility in Texas or New Mexico, or even to Nevada’s Yucca Mountain. However, moving the radioactive material over long distances and to someone else’s backyard is just as contentious.
The storage of spent nuclear fuel has always been controversial. While a permanent storage facility would be the ideal solution, there is no political will to get that done. Therefore, on site storage has been the most practical method. And this is the unenviable position in which Southern California Edison now finds itself — and one to which the California Coastal Commission can relate. Unless the federal government steps in and overrules the commission’s decision, the spent fuel will start going from wet storage to dry storage in 2020.
Date: Oct 23, 2019