Mothers for Peace filed a strong objection to an August 12, 2020 “exigent” (urgent) License Amendment Request (LAR) by Pacific Gas & Electric Company (PG&E) to the U.S. Nuclear Regulatory Commission (NRC). PG&E has received permission from the NRC to assess and repair suspected degraded safety-related cooling pipes on Diablo Canyon Unit 1 while the plant continues to operate at full power.
PG&E aims to avoid shutting the plant down as required by technical specifications. PG&E intends to disable the auxiliary feedwater system, a vital cooling mechanism, for seven days while it inspects and repairs the degraded pipes. Yet, the operating license issued by the NRC requires the reactor to be shut down if this cooling system is out-of-service for more than three days.
Based on expert testimony from nuclear engineer David Lochbaum, Mothers for Peace contends that PG&E has not demonstrated that the auxiliary feedwater system (AFW) can be safely disabled for the extended time period proposed by PG&E. If an earthquake or other accident were to occur while the AFW is disabled, it would significantly increase the risk of a core melt accident.
Mothers for Peace Board Member Jill ZamEk compares PG&E’s plans to “changing your brake pads on your vehicle while driving 70mph on the freeway!”
Mothers for Peace has also raised the alarm that PG&E’s belated discovery of corroded AFW pipes shows that PG&E’s program for monitoring safety equipment is inadequate and negligently administered. If PG&E had conscientiously complied with NRC orders issued in 1986 to monitor the thickness of AFW pipes as the plant aged, this safety problem would not have occurred. “As we witnessed when PG&E pipelines blew up in San Bruno and when PG&E transmission lines burned down Paradise, maintenance is not PG&E’s strong suit,” states Mothers for Peace spokesperson Jane Swanson.
The NRC has protected PG&E from public criticism of its risky behavior and negligence by processing PG&E’s License Amendment Request on an expedited basis, without providing adequate public notice and delaying public release of critical documents relating to PG&E’s request. The NRC gave the public only 24 hours to provide comments on whether the proposed License Amendment Request poses a significant safety hazard, rather than the usual comment period of 30 days. And some of the key documents were not posted until August 21, the due date for comments. Linda Seeley, a spokesperson for Mothers for Peace, said “We are outraged by the NRC’s disregard for public safety and the participation process. This lack of transparency and time to prepare comments makes a mockery of that process and puts the Central Coast at risk of a nuclear meltdown.”
The auxiliary feedwater (AFW) is a critical safety system designed to flood a reactor’s core with cooling water in the event of an emergency. Fukushima demonstrated what happens when this cooling mechanism fails. A leaky AFW system is also hazardous to reactor workers: burst AFW pipes have killed workers at both U.S. and Japanese reactors in the past. These deaths led the NRC to establish strict requirements for AFW monitoring in the 1980s.
Significantly, the only reason PG&E knows it needs to do this inspection and repair is because the problem of thinning and leaking pipes was discovered by sheer luck in Unit 2 a few weeks ago. Unit 2 was shut down to correct a problem of excess and potentially explosive hydrogen when an employee happened to notice leaks in the AFW pipes. Upon inspection, PG&E discovered that erosion by the salty marine environment had caused dangerous thinning of the pipe walls.
See the complete filing by Mothers for Peace attorney Diane Curran, supporting declaration by expert witness David Lochbaum, and AFW technical background information.