nuclear-news

By Shalina Chatlani  Southern California Edison will soon resume storing spent nuclear fuel at San Onofre Nuclear Generating Station. The move comes almost a year after a near-miss accident, when one of the canisters that contained the spent nuclear fuel nearly fell 18 feet.

Resuming storing the fuel has also reignited concerns from residents who live around San Onofre on whether storing 1,700 tons of nuclear waste next to the beach is safe.

Residents still worried

Many of those concerned residents, like Peter McBride of Oceanside, attend regular meetings of the San Onofre Community Engagement Panel.

“Nobody has talked about the half-life of the nuclear waste that’s there,” he said at a June meeting. “Some of (the nuclear waste) goes quickly. But some of it goes 24,000 years. We’re talking about canisters … that are going to hold it for 10 to 60 years. It’s ridiculous.”

McBride and others at the meeting said the canisters are too thin, and with the salt air, they will corrode and break open. Some also said rising ocean levels could smother the canisters in water and cause them to breach.

“I’m worried about the fact that not only this area but other areas of the country face the same kind of irresponsibility with this potentially disastrous material,” McBride said. “I’m worried about our children, my grandson.”

San Onofre’s senior nuclear engineer Randall Granaas said residents shouldn’t be concerned. He recently led KPBS on a tour of the station and said any danger would come from heat and radiation.

Right after being removed from the reactor, fuel rods are extremely hot. They are then put in cooling ponds for five to seven years.

“After five years then we can transfer it into this dry storage system,” he said. “And that’s adequate, using the natural convection to cool the fuel.”

Granaas said vents on the canisters allow cold air to come in, so the heat can circulate out.

There is, however, still the issue of radiation. Even spent nuclear fuel is highly radioactive. Part of that radiation can go through some materials, like aluminum, but not through steel or concrete. The radiation, known as gamma, can take years to dissipate.

“So if you had no shielding between our fuel and yourself, it could be fatal in a relatively short amount of time. So it is important to maintain that shielding,” Granaas said. “But if you fast-forward several hundred years from now you can walk up to one of those fuel assemblies for a short period of time and you’ll be fine.”

But we can’t fast forward — that has residents such as McBride worried. What would happen if the shielding suddenly went away?

Storage is structurally sound, officials say

At San Onofre’s spent fuel site, a thick concrete slab acts as a 35,000-pound lid. It sits on top of a 20-foot crevice, where the fuel canisters are stored. Officials say this system can withstand massive amounts of stress.

Still, some scientists are skeptical.

Physicist Tom English told KPBS he thinks there are a number of ways this operation could go wrong.

“They’re basically going to put the stuff in a thin storage container, which probably will have some problems with corrosion given this ocean environment here,” he said. “The second idea is they’re going to store it such that it will be about 100 feet from the water and a few inches above the groundwater table, which is totally ridiculous. As the sea level rises, what will happen is the bottom of the containers will corrode.”……. https://www.kpbs.org/news/2019/jun/19/nuclear-waste-beach-science-and-safety-explained/