San Onofre Nuclear Power Plant

On the coast midway between Los Angeles and San Diego is the now-shuttered San Onofre nuclear power plant. An accident or terrorist event there could have taken out much of Southern California.

We opposed it from the beginning. Dr. Sheldon Plotkin, a safety engineer and long-time CBG Board member, testified as an expert witness during the licensing proceeding that the emergency plan could not possibly work. Freeways were already jammed much of the time, even when there was no nuclear accident to escape from. If there were a nuclear evacuation ordered, there was simply no way to get people out in time. Southern California Edison (SCE) had assumed in its analysis that essentially every square foot of freeway would be filled with cars, with no space between them, and all cars going 65 miles an hour, with no traffic jams, crashes, or other impediments. Dr. Plotkin showed how this couldn’t work, but the NRC rubber-stamped the approvals anyway

In January 2011, CBG launched its “Truth to Power Campaign” headed by S. David Freeman, who had previously run the Tennessee Valley Authority, the LA Department of Water & Power, and the Sacramento Municipal Utility District. It was aimed at rapidly phasing out nuclear power and replacing it with renewables, and soon focused on shutting down California’s nuclear plants, San Onofre and Diablo Canyon.

In 2012, the year after the Fukushima accident, San Onofre was unexpectedly shut down because of rupture of some steam generator tubes and associated release of radioactivity. SCE was cagey about how many tubes were damaged and the seriousness of the problem. We immediately recognized, however, that the situation was considerably more worrisome than SCE had disclosed.

Steam generators are critical features of a nuclear reactor. They help extract heat from the nuclear fuel, essential to preventing it from melting, and they provide a pathway for radioactivity to be released from the containment structure into the environment. San Onofre’s steam generators were supposed to last the lifetime of the reactor, but wore out prematurely, so SCE had to buy new ones (they are huge and very expensive) and replace them. The new ones were only a year or two old when they failed.

In a tense exchange at a huge public meeting, Dan Hirsch got SCE to admit that not just a few but thousands of steam generator tubes were damaged. Dorah Shuey and Dale Bridenbaugh helped produce a detailed CBG report examining the history of steam generators nationally that showed that the San Onofre failures were orders of magnitude greater than experienced virtually anywhere else. Senator Boxer provided our report to the NRC Commissioners at a Senate hearing, calling on all of them to review it and respond. Dan Hirsch then testified before the NRC about the problems.

An Atomic Safety and Licensing Board was established to review SCE’s request to restart one of the San Onofre reactors without fixing the steam generators. Citing in part the CBG report, the Board refused to allow it, requiring instead a full license amendment hearing on the safety of restart. SCE then withdrew the request and announced the reactors would be permanently closed, an astonishing victory.