March 11, 2011: An very important earthquake occurred off the coast of Japan. At 3:41 p.m. the resulting earthquake tsunami hit the Fukushima plant. Three of six reactors at the Fukushima nuclear power plant were in operation when the earthquake struck and Safe Stop has worked for all three reactors. But the tsunami wave was at least 14 meters high, while the plant was built to withstand a tsunami about 6 m tall. Thus, the power cuts caused by the earthquake were worsened by the failure of backup generators. In the reactors the radioactive nuclei were in two places: a) At the heart of the reactor in which fissile bars produced energy during times of normal operation. b) In storage pools containing bars that had already been used, but the radioactivity was still too large to be stored elsewhere. Since radioactivity produced a lot of heat as the water cooling was not working, there was overheating followed by partial melting of the radioactive material. On contact with water, the hot iron produced hydrogen: $2Fe$ $ + $ $3H_2O$ $\longrightarrow$ $3H_2 $ $+ $ $Fe_2O_3$ A mixture of hydrogen and oxygen in the presence of catalysts exploded: $2H_2$ $+$ $O_2$ $\longrightarrow$ $2H_2O$ Radioactive isotopes were thrown in the air after the explosions and were also mixed with the sea water which the Japanese had to use to cool the reactors at all costs.
Fanciful values of dose are circulating. Here are the values that seem assured:
