By John Stang
Pacific Gas & Electric plans to issue a request for proposals around September for accelerated transfer and storage of spent nuclear fuel at the Diablo Canyon nuclear power plant near San Luis Obispo, Calif.
Representatives from the utility briefed its Diablo Canyon Decommissioning Engagement Panel on this plan during a March 13 meeting.
The utility expects to close its two Diablo Canyon reactors in November 2024 and August 2025. It wants to accelerate completion of fuel movement from 10 years after 2025 to seven years after that date. That would save money while also giving PG&E extra time to deal with unexpected problems in the process, Mark Mayer, PG&E’s manager for nuclear fuel purchasing, told the panel.
There was no immediate word on the schedule for completing the procurement.
Pacific Gas & Electric is also exploring whether better cask technology might be available to deal with heat from the used fuel than the Holtec 100 system currently used at Diablo Canyon, said utility spokeswoman Susan Hosn.
Officials mentioned three potential storage cask vendors Wednesday: Holtec, NAC International, and Orano. However, Hosn said other vendors would be welcome to send proposals.
Since 2009, PG&E has competed seven campaigns to transfer used fuel to a dry storage site at Diablo Canyon. The pad holds 1,856 used fuel assemblies in 58 casks. Another 1,596 assembles are in the plant’s wet storage pools.
Diablo Canyon’s Nuclear Regulatory Commission license allows it to store 138 loaded casks containing 32 assemblies in each cask — meaning a total of 4,416 assemblies, Hosn said.
PG&E might consider adding movement and storage of the site’s Great-Than-Class-C waste to the RFP. However, extra engineering work is needed before this decision can be made. PG&E expects a maximum of 10 casks to be needed for this waste if the Holtec 100 canisters are used.
On Jan. 29, PG&E filed for Chapter 11 bankruptcy in U.S. Bankruptcy Court for the Northern District of California, due to expected liabilities of $30 billion or more connected to wildfires in the state in 2017 and 2018. PG&E’s transition lines and other equipment have been blamed for many of the fires.
The Diablo Canyon decommissioning trust fund currently has $3.2 billion, with the utility seeking permission from the California Public Utilities Commission to increase rates to provide another $1.6 billion it says it will need to complete that work. The commission is expected to take 12 to 18 months to rule on that matter.
So far, the utility has publicly said the bankruptcy and reorganization will not affect its decommissioning plans.
Panelists and members of the public express concern at the meeting about the possibility of used fuel being stored for an extended period at Diablo Canyon.
The Department of Energy’s planned spent fuel disposal site at Yucca Mountain, Nev., remains stalled and interim storage sites in New Mexico and Texas are still working their way through the NRC licensing process.
“We have to assume the wastes will be stored here for decades or a hundred years,” said Jane Swanson, president of the San Luis Obispo Mothers of Peace.
Diablo Canyon Decommissioning Engagement Panel member Alex Karlin worried about the panel’s ability to double-check PG&E’s plan.
“This panel has no competence or basis to tell what PG&E tells us is right or wrong,” said Karlin, an environmental attorney.
