Edison Proceeds With Plans To Bury Nuclear Waste At San Onofre Site

Monday, September 18, 2017
By Alison St John
Credit: Google Earth
Above: Google Earth image showing new location of nuclear waste storage site at the San Onofre Nuclear Power Plant (bottom left corner).

Southern California Edison said it will start burying spent nuclear fuel from the now-closed San Onofre Nuclear Generating Station by the end of this year.

Opponents of the decision, at a Sept. 14 meeting of the San Onofre Community Engagement Panel, said Edison should wait till after a strategic plan for the waste is done.

A legal settlement adopted in August requires Edison to develop a strategic plan for how and where to store the nuclear waste from San Onofre.

Ray Lutz, of the group "Citizens Oversight," was a plaintiff in the lawsuit. He said Edison should delay its plans to bury tons of spent nuclear fuel to canisters 100 feet from the ocean.

“The settlement calls for them to hire experts and come up with a strategic plan for how they’re going to develop another offsite location,” Lutz said. “We want to have that settlement done before they start mindlessly moving the fuel.”

Lutz said it would be better to keep the waste in spent fuel pools until a permanent site is found for it elsewhere.

“Because there is an option — a load-and-go scenario — where the waste would be loaded onto a train and onto another site," Lutz said. "The less handling you can get involved, the better.“

But Tom Palmisano, chief nuclear officer for San Onofre, said the new onsite storage system is now ready and he will start moving the spent fuel by the end of this year.

“A spent fuel pool is not the best choice for storage of fuel at a decommissioning plant,” he said. “Dry cask storage — when the fuel is ready to move to it — is a better choice, and we’re committed to that."

Palmisano said the recent legal settlement has no bearing on his existing plans to move the fuel into canisters buried in concrete on site.

“The settlement is not tied to moving spent fuel from spent fuel pools to dry cask storage,” he said. “That is not part of the settlement."

There is no time line in the settlement for when the strategic plan should be complete. Finding an alternative site to store the waste could take years.

Inspecting the canisters

One change to Edison’s plans that was agreed to in the settlement was a commitment to develop an inspection and maintenance plan for the stainless steel canisters by 2020. That is two years earlier than Edison committed to in 2015, when the California Coastal Commission granted the company the permit to bury the waste.

The technology to inspect the canisters had not yet been fully developed. The task of checking for cracks is made more difficult by the small space between the canister’s stainless steel walls and the surrounding concrete.

Without a permanent storage site, tons of nuclear waste already sit in about 50 horizontal canisters at San Onofre. The storage system, designed by Areva, will need re-licensing in 2022.

Lisa Edwards, senior project manager of Radiation Safety at the nonprofit Electric Power Research Institute, spoke at the Community Engagement Panel meeting. She described ongoing research into how to conduct Aging Management Plans for the storage systems. She described using micro robots to test the most susceptible areas, using technology like acoustic emissions and “Eddy currents,” an electromagnetic current like a sonogram.

“Think of this as a starting point” she said.

Edison plans to add 73 vertical canisters, filled with 3.6 million pounds of spent fuel, to its existing onsite storage system of 50 horizontal canisters. The process of moving them out of the spent fuel pools and into Holtec's dry-cask storage system is expected to start at the end of this year and take about 18 months.