Japanese Earthquake Prompts Questions about California's Nuclear Power Plants

Looking at the failure of three cooling systems at nuclear power reactors in Japan and a second containment building explosion, I can’t help but wonder about the shortsightedness of building nuclear plants near an earthquake fault. The question arises, are we at risk here in Southern California?

Southern California Edison proudly proclaims that the San Onofre Nuclear Power Plant was built to withstand a 7.0 quake and 25-foot tall tsunami.

More problematic is the aptly named El Diablo Canyon Power Plant, 160 miles up the coast from Marina del Rey in Avila Beach. It’s a good place to build a power plant, except for four earthquake faults in the vicinity.

The design was considered safe enough to resist shaking from the nearby San Andreas Fault when construction began in 1968. But in 1973, a new fault was discovered three miles off shore, the Hosgri fault. In 1927,  a few miles farther out, it had produced a 7.1-magnitude quake. Yet construction at El Diablo continued.

In 1979, tens of thousands of protestors gathered to try to block the plant's construction.  Two years later, hundreds of activists were arrested. The plant was ultimately finished with a design intended to withstand a 7.5-magnitude earthquake. It went online in the mid-80s.

The nuclear power plant on the coast to the north of Marina del Rey and the one to the south are designed to resist a 7.5 and 7.0 quake respectively. To put this in perspective, the plants would be safe in a quake the size of the one that hit Haiti last year but would not be in an earthquake as big as the one that leveled San Francisco in 1906. That was a 7.8.

Because the Richter Scale is logarithmic, each whole number represents a change in earthquake amplitude by a factor of ten, but that only tells part of the story. As as an estimate of energy expended by a quake, each whole number represents about 31 times more energy than the amount released by the previous number.

Experts are predicting that the next quake on the San Andreas Fault could be

When? Thomas Jordan, Director of the Southern California Earthquake Center, has said repeatedly that the San Andreas fault is ". It's been a long time since an earthquake has occurred on that fault — over 150 years."

We are being reassured that quakes of around 8 are the most we could expect in California because the fault geology is different here than it is in Japan. In fact the biggest quake recorded in California history was the 1857 Fort Tejon earthquake, on the San Andreas fault, which reached 7.9. 

But Friday's 8.9-magnitude earthquake was the biggest in Japanese history. It is now estimated to have killed 10,000 people, pushing Japan 13 feet closer to North America, shortening the earth's day and tilting the planet off its axis.

California didn’t escape unscathed. The tsunami caused an estimated $50 million of damage to our coast.

President Obama has repeatedly mentioned that he supported new nuclear power plant construction to help wean us off fossil fuel dependency, yet if we learn anything from the disaster in Japan, it should be that if we built any additional nuclear plants, they should be in areas more seismically stable than El Diablo Canyon.

My heartfelt good wishes go out the Japanese people. They have suffered a devastating blow and could use our help and prayers.

After quakes in close succession around the Pacific ring of fire, first in New Zealand and now Japan, I hope that that California's faults remain quiescent.