Wasted forever: Radioactive material likely to remain at Diablo Canyon long after it's shut down 

With the announcement that energy giant PG&E plans to shut down the Diablo Canyon nuclear power plant by 2025, San Luis Obispo County residents are trying to work out just what a future without the controversial facility will look like.

Before the plant’s two reactors are shut down for good, SLO County has nine years to prepare for what will disappear once Diablo Canyon’s operations cease. Nearly a billion dollars for the county’s economy annually? Gone. An estimated 1,500 jobs? Also gone.

But for all SLO County will lose as the plant closes, it will be left with something that will likely stick around far beyond 2025: all the radioactive material used to power its reactors.

The nuclear power industry and government regulators refer to it as “spent fuel.” Anti-nuclear activists call it “nuclear waste.” Whichever name you choose to call it, the material is integral to the creation of nuclear energy, and it remains stored on-site at most plants even after they’ve been shut down.

Diablo Canyon’s reactors are fueled by pellets of radioactive material placed in rods and grouped in bundles called fuel assemblies. Those assemblies are placed into the reactors and irradiated, generating heat to create the steam that powers turbines to produce electricity from a generator. After three to five years, those fuel assemblies are replaced. And while they aren’t strong enough to power the reactors, they still retain heat and remain radioactive.

Until 2009, used fuel assemblies were stored in two massive cooling pools. Today, Diablo Canyon uses a system of moving spent fuel from the pools after a period of about seven years and placing them into large concrete and steel containers, “dry casks,” which are stored on-site.

According to data from the U.S. Energy Information Administration (EIA), there were 2,848 spent fuel assemblies stored in the pools or casks at Diablo Canyon as of June 2013, when the EIA last surveyed the facility. 

That number has likely increased since 2013, and will continue to do so as Diablo operates for another nine years. PG&E Spokesman Blair Jones said the site’s current dry cask storage capacity is ample enough to take on additional spent fuel until the plant shuts down. 

“There is enough space in the dry cask storage facility to hold all the fuel that has currently been used to date, as well as the fuel that will be used to get us out to 2025,” Jones told New Times.

PG&E’s license for its independent spent fuel storage operations expires in 2024, but the company’s proposed plans for the shutdown say that it will seek to renew those licenses with the Federal Nuclear Regulatory Commission no later than 2019. 

At a June 28 California State Land Commission hearing, PG&E President Geisha Williams stated that the spent fuel would be safely stored on-site until the federal government “delivers on its promise” of a long-term, off-site storage facility. Those comments referenced lengthy, complex, and ongoing attempts at the federal level to create an integrated system to take spent fuel from sites like Diablo Canyon and store it in deep underground repositories. But that’s easier said than done. Despite a mandate under the 1982 Nuclear Waste Policy Act to study and designate such sites, the U.S. Department of Energy blew past its deadline to do so long ago. 

“A solution to siting, transporting, and disposing of our spent nuclear fuel and high-level radioactive waste will take decades to implement,” reads a statement regarding the issue on the DOE’s website.

While the federal government continues trying to tackle the issue, spent fuel at shuttered nuclear power plants remains on site. Such is the case with the Maine Yankee Nuclear Power Plant in Wiscasser, Maine. The plant was shut down in 1997 and eventually completely dismantled. But nearly 20 years after that shutdown, the spent fuel is still there, in the plant’s dry cask storage facility, and Maine Yankee is still responsible for managing the site, according to spokesman Eric Howes.

“As you know, it’s the federal government’s responsibility to remove the spent nuclear fuel,” Howes told New Times. “The spent fuel will remain at [Maine Yankee] until the federal government conforms.”

Howes said the cost to maintain the fuel storage site at Maine Yankee is about $10 million a year. To pay for it, Maine Yankee sued the federal government three times, winning millions from the lawsuits. Having the 11-acre fuel storage site at Maine Yankee also means the rest of the roughly 180 acres of land the plant used to sit on can’t be sold or repurposed. 

“Until the federal government removes that fuel, the property is basically unavailable for other uses,” Howes said.

PG&E will likely be in the same situation, barring any sudden breakthroughs at the federal level, and will be required to provide resources for management, oversight, and even physical security for the Diablo Canyon spent-fuel storage area even after the rest of the facility has been dismantled, all but guaranteeing that the company, the casks, and the material they house will remain a fixture on the coastal property that PG&E President Williams described to the State Land Commission as “beautiful” and “majestic.”

PG&E, government regulators, and SLO County citizens will have ample time to wrestle with the issue. Williams said it would take two to three years to create a decommissioning plan for Diablo Canyon, and once it’s approved, the process could take as long as 20 years. 

Staff Writer Chris McGuinness can be reached at [email protected], or on Twitter at @CWMcGuinness.