Japan underestimated the risks of tsunami that led to the nuclear crisis at the Fukushima No. 1 nuclear plant, the International Atomic Energy Agency said in a preliminary summary Wednesday, while pointing out the need to reinforce the independence of its nuclear regulators.
"The tsunami hazard for several sites was underestimated. Nuclear designers and operators should appropriately evaluate and provide protection against the risks of all natural hazards," reads the IAEA summary.
The IAEA team of experts — which arrived in the country May 23 — visited the Fukushima Nos. 1 and 2 plants, as well as the Tokai No. 2 plant in Ibaraki Prefecture, to investigate the sites in an effort to glean lessons on nuclear safety from the ongoing crisis.