Experts said that the decision to pump seawater into the unit was a recognition that the elaborate system of valves, pumps and pipes, and the layers of steel and concrete, might not be enough to guarantee that the nuclear facility could avoid a disaster of Chernobyl proportions.
The water and boric acid would absorb neutrons, Tokyo Electric said. But experts said it would also make it unlikely that the plant would operate again.
It was a one-two punch. First the quake -- bad enough. And then the flood. What actually happened inside Fukushima Daiichi?
The explosion inside Fukushima Daiichi unit 1 destroyed a building that housed both the reactor vessel and its containment structure. It was caused by hydrogen, which nuclear experts said could only have been produced from inside the reactor vessel by the exposure of zirconium cladding that surrounds the fuel rods. Those rods are supposed to be covered by water, but at very high temperatures, steam reacts with the zirconium and produces hydrogen.
When pressure rose in the reactor vessel, it vented the gas into the containment structure and then into the outer building. Experts believe devices designed to ignite the hydrogen before it reached dangerous levels were not working because of power failures.
Those power failures helped start the crisis at the nuclear plants. After grid power was knocked out by the quake, the tsunami flooded and disabled backup diesel generators, and battery power ran out. ...Washington Post
In a country as huge as the US, we can hardly imagine a place like Japan having so few energy resources. They are dependent on nuclear power in a way that we aren't. Of course, if inhabitants on this planet learn quickly enough from recurring disasters like this one, we'll find and use much safer sources of energy. If.
