This was not unexpected, but it is shocking and depressing:
Sunday, March 13, 2011
Meltdown Caused Nuke Plant Explosion: Safety Body
TOKYO (Nikkei)–The Nuclear and Industrial Safety Agency (NISA) said Saturday afternoon the explosion at the Fukushima No. 1 nuclear plant could only have been caused by a meltdown of the reactor core.
The same day, Tokyo Electric Power Co., which runs the plant, began to flood the damaged reactor with seawater to cool it down, resorting to measures that could rust the reactor and force the utility to scrap it.
Cesium and iodine, by-products of nuclear fission, were detected around the plant, which would make the explosion the worst accident in the roughly 50-year history of Japanese nuclear power generation.