“The earthquake and tsunami of March 11, 2011, were natural disasters of a magnitude that shocked the entire world. Although triggered by these cataclysmic events, the subsequent accident at the Fukushima Daiichi Nuclear Power Plant cannot be regarded as a natural disaster. It was a profoundly manmade disaster—that could and should have been foreseen and prevented.”
—Kiyoshi Kurokawa, “Message from the Chairman,”
The Official Report of The Fukushima Nuclear Accident Independent Investigation Commission
Three years ago, the biggest recorded earthquake in Japanese history hit Tohoku prefecture, leaving more than 20,000 people dead or missing. On the heels of the destructive magnitude 9.0 earthquake came a tsunami that reached a run-up height of 30 meters in some areas, sweeping entire towns away in seconds. Within the affected area were three nuclear power plants: the Fukushima Daiichi and Daini nuclear power plants operated by the Tokyo Electric Power Company (TEPCO), and the Onagawa Nuclear Power Station operated by the Tohoku Electric Power Company. While the three power stations shared similar disaster conditions, nuclear reactor types, dates of operation, and an identical regulatory regime, their fates were very different. The Fukushima Daiichi plant experienced fatal meltdowns and radiation releases. Fukushima Daini was damaged by the earthquake and tsunami, but the heroic efforts and improvisations of its operators resulted in the cold shutdown of all four operating reactors. Onagawa managed to remain generally intact, despite its proximity to the epicenter of the enormous earthquake.
Everyone knows the name Fukushima, but few people, even in Japan, are familiar with the Onagawa power station. Fewer still know how Onagawa managed to avoid disaster. According to a report by the International Atomic Energy Agency mission that visited Onagawa and evaluated its performance, “the plant experienced very high levels of ground motion—the strongest shaking that any nuclear plant has ever experienced from an earthquake,” but it “shut down safely” and was “remarkably undamaged.”
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