Nuclear security

Chernobyl, Fukushima, and preparedness for a "next one"

April 26 marks the 30th anniversary of the Chernobyl disaster, and those old enough to remember the event can recall the explosion, the evacuation, and the dread. But they rarely remember an immense milestone in the response to the disaster: the completion in November 1986 of a concrete encasement of Chernobyl's reactor number four. Workers drawn from all across the Soviet Union built this "sarcophagus" under extreme radiological conditions, on the ruins of the destroyed reactor. They used unimaginable amounts of concrete—and a great deal of imagination. This concrete mausoleum has held up, with some assistance, for 30 years now. (A larger containment structure that will fit over the existing sarcophagus is now being built.)

Over the years, as the ranks of those who responded to Chernobyl have thinned, new generations of nuclear professionals have been trained to prevent another disaster. Their training has emphasized "safety culture." This, along with "inherently safe designs," was going to guarantee an accident-free nuclear future. For a while, it seemed as if the world was on the verge of forgetting forever what responding to a nuclear emergency really required. Then, in March 2011, multiple reactors at one of the world's largest nuclear power plants melted down as a consequence of a massive earthquake, a tsunami, and a sustained power outage.