Fukushima Nuclear, Eleven Hundred Aftershocks Later

Emergency workers trying to slow the melting of nuclear fuel at the Fukushima Daiichi power plant were forced to abandon their posts yesterday after another powerful earthquake triggered an evacuation order. The quake also knocked out grid-power to two nuclear plants in northern Japan, although cooling was maintained using backup power sources.

The evacuation of the Fukushima power plant came at a particularly precarious time, as newly released details highlighted the degree to which the situation there continues to worsen. Speculation mounted this week that at least part of the melting nuclear fuel inside reactor 2 had burned through its steel containment structure, and cooling passages are believed to be blocked in reactor 1, where pressures continue to rise alongside fears of another hydrogen explosion.

Yesterday’s quake, measuring 7.1 on the Richter scale, was the fifth major earthquake in the region over the past 30 days, and one of more than 1100 aftershocks since the March 11 disaster.

Data from U.S. Geological SurveyAll of this should call into question the sanity of building nuclear power plants in earthquake zones, where the loss of electric power needed to run cooling pumps quickly leads to disaster.

And California’s nuclear plants would be no match for the punch that Japan’s recent earthquakes are packing. A magnitude 7.1 earthquake like the one that struck yesterday releases 40 percent more energy than one measuring 7.0 – the level that California’s San Onofre Nuclear plant was built to withstand. Reactors at Diablo Canyon are rated to for a more powerful 7.5 quake, but three of the 241 quakes that struck Eastern Honshu on March 11 were stronger than that. With magnitudes of 7.7, 7.9, and 9.0, these three quakes respectively released 2-times, 4-times, and 180-times the energy that Diablo Canyon was built to survive.

Proponents of nuclear power can continue their little waggle dance as long as they like, but nuclear power is already doomed -- even before the current crisis is over. And unfortunately it's far from over, because in Japan, there's still a whole lotta shakin' goin' on.