The federal Nuclear Regulatory Commission said on Wednesday that Diablo Canyon nuclear power plant operated safely during 2014.
The agency held its annual public meeting to discuss the performance of Diablo Canyon and take input from the public. More than 80 members of the public attended the meeting, held at the Embassy Suites hotel in San Luis Obispo.
About a dozen people came wearing green Friends of Diablo Canyon T-shirts to show their support for the continued operation of the plant.
Tom Hipschman, NRC senior resident inspector at Diablo Canyon, said the NRC conducted 7,300 hours of inspections at Diablo Canyon in 2014. Also in 2014, an analysis of the plant regarding its seismic and flooding hazard showed the plant could safely shut down in the event of an earthquake.
The NRC did note one problem at Diablo Canyon involving the plant's emergency evacuation planning. From 2005 to 2013, the emergency plan lacked a requirement to evacuate boats at sea within 10 miles of the plant in the event of a radioactive release.
Officials with Pacific Gas & Electric, which owns the plant, and the NRC said the omission had low to moderate safety significance because the county had evacuation plans in place that would have required boats to leave the area.
However, the omission resulted in one of the plant's inspection findings to be reduced from green to white and an additional inspection will be performed later this year.
Blair Jones, a PG&E spokesman, said the utility noticed the error and brought it to the attention of the NRC.
"It was our relentless focus on safety that led us to identify and correct a technical procedure change in our previous emergency response plan," he said.
Barry Allen, PG&E director of nuclear services, said the utility did a thorough review of its emergency preparedness program to correct any similar problems.
During public comment, Jane Swanson, a spokeswoman for San Luis Obispo Mothers for Peace, said PG&E has a history of safety lapses, especially regarding storage of highly radioactive used fuel.
She cited the fact that PG&E did not load 19 of its 34 used fuel dry storage casks according to a technical specification made by the casks' manufacturer, Holtec International, regarding the proper mixture of older and newer spent fuel to ensure proper heat dissipation.
The specification was outdated and has been removed, PG&E officials said. The NRC is reviewing the incident but does not consider the issue to be a safety violation. The sealed casks could not emit any radiation, said Lara Uselding, NRC spokeswoman. PG&E will file a license amendment application to fix the problem.
Marc Dapas, NRC regional director for the western United States, said the error showed a disconnect between PG&E's safety culture and its adherence to safety specifications and encouraged PG&E to correct any underlying problems that caused the oversight.
Ed Halpin, PG&E chief nuclear officer, said there was some confusion over the specification and the dry cask loading process was shut down for a week to review the dry cask specifications.
Swanson asked the NRC assure the public that the dry casks at the plant are properly guarded.
"Given that the NRC's mandate includes protecting people and the environment, these casks need to be under guard day and night," she said.
The dry casks, like all of Diablo Canyon's facilities, are guarded around the clock by a highly trained and heavily armed security force, Uselding said.