Japan Lesson: Slowly Relicense California Nukes
Posted Mar. 24, 2011, 6:56 am
Tom Elias / Mirror Columnist
Foresight is a quality rarely seen among politicians in Sacramento, which makes it remarkable that 10 state legislators actually displayed a lot of it barely two weeks before the devastating March 11 9.0 Japanese earthquake and the nuclear power plant crisis that followed.
The group of 10, mostly Democrats, but notably including Republican state Sen. Sam Blakeslee of San Luis Obispo, fired off a letter in late February to the U.S. Energy Department’s Blue-Ribbon Commission on America’s Nuclear Future begging the federal team to hold hearings in California before the Nuclear Regulatory Commission (NRC) relicenses the Diablo Canyon or San Onofre nuclear power plants. Blakeslee’s participation is notable not only because his party usually wants the wishes of big industries and utilities rubber-stamped, but also because he’s the Legislature’s lone geophysicist, with a doctorate in earthquake studies.
Current licenses for both plants run well into the 2020s, but the owners of each are already working toward relicensing. Pacific Gas & Electric Co. has applied to renew its permits for both units at Diablo Canyon, on the coast at Avila Beach in San Luis Obispo County. That plant’s license was last approved without an earthquake response plan, because Diablo Canyon is built to withstand the 7.5 temblor thought to be the maximum possible for its location.
Southern California Edison, operator of San Onofre, is expected to apply for license renewals at Units 2 and 3 of that plant, adjacent both to a state beach and the Interstate 5 freeway south of San Clemente, at the northern edge of the U.S. Marines’ huge Camp Pendleton base.
The message of the 10 legislators was not necessarily to deny renewals, but to take them slowly. The same message was echoed just after the Japanese quake by California’s two U.S. senators, Democrats Barbara Boxer and Dianne Feinstein.
And why not go slowly, especially after explosions, radiation leaks, and fires rocked Japan's Fukushima Daiichi nuclear power plant following the big quake and the disastrous tsunami that slammed ashore a short time later.
For one thing, license expirations are not imminent: the earliest comes in 2022. Plus, the state of seismic knowledge has advanced considerably since the two California plants were last licensed. So a complete examination of their operations is in order, even if there is no known imminent threat.
“Concern over seismic events at nuclear power plants in California is not a new issue,” wrote the state lawmakers. They noted that a nuclear plant at Humboldt Bay was closed for seismic retrofitting in 1976 because of newly known earthquake faults and was later decommissioned.
They also noted that when a 6.8 quake in 2007 jolted Japan’s Kashiwazaki nuclear facility, the world’s largest, ground motion nearly doubled the maximum for which that plant was designed. The latest quake also far exceeded design expectations. How can we be sure the same thing won't happen here the lawmakers asked.
“We believe the seismicity and remaining uncertainty of California creates concerns,” they said.
What concerns? While both PG&E and Edison have issued soothing statements since the Japanese disaster about how prepared their plants are and how they’re designed to take the maximum possible movement of any known nearby faults, plenty is known today that was not a few years ago.
For one thing, the U.S. Geological Service in 2008 reported discovering a previously unknown “significant” fault directly beneath Diablo Canyon, meaning there are at least two active faults in its immediate vicinity. A quake on one fault can sometimes trigger movement on others nearby, creating more earth movement than the known maximum for any single fault in the area.
The legislators added that “there is credible reason to believe that the design basis … approved by the NRC at the time of licensing (San Onofre) may underestimate the seismic risk at the site.” This doesn’t make San Onofre unsafe, they said, but it may mean its margin of safety is less than previously thought.
While no one accuses either PG&E or Edison of deliberately understating risks, that has happened at other American nukes, most notably New York’s Shoreham Nuclear Power Plant, where builders were found by federal investigators to have lied in 1988 about seismic safety factors.
So it behooves Californians and federal regulators not to meekly accept the statements of the big utilities. They’ve been wrong before, as when PG&E told the state just prior to the 2008 USGS report of a new fault that, “We believe there is no uncertainty regarding the seismic setting and hazard” at Diablo Canyon.
The Japanese crisis, complete with evacuation of half a million persons and a radiation quarantine zone extending 19 miles around Fukushima Daiichi, demonstrates that the risks of nuclear power – entirely aside from problems with storing radioactive waste – dictate going slowly whenever possible. And the long time frame before California’s two nukes actually need relicensing mandates not just hearings, but very careful analysis of all potential hazards and the reliability of all planned safety and mitigation measures.