It said;

Once the reactors automatically shut down following the quake and if normal electrical power supplies are cut off, diesel generators are supposed to kick in to power an emergency core cooling system to prevent meltdown of the nuclear reactor. Unfortunately, the diesel generators were swamped by the tsunami and failed. This opened the door to meltdown, which creates the potential for radioactive materials to be released into the environment.

These events have led the government to declare a "nuclear emergency situations" for the first time ever, destroying the credibility of the claim by the government and electric power industry that nuclear power generation is safe. Japan's nuclear power generation policy must be strictly reviewed.