Radioactive cobalt detected! Tokyo will never be evacuated, even in a worst-case scenario.

It's just too big. There is no place to move the 13 million slaves. No evacuation order will be issued. They will just play it down untill people start becoming sick, to keep the government functioning.



They have detected radioactive cobalt, most likely cobalt-60, in the Ocean near the Fukushima nuclear power plant. This is bad, cobalt-60 is what they would've used in a cobalt bomb, a so called salted bomb. Forget plutonium, cobalt-60 is even more radioactive.



If we have a catastrophic meltdown in the reactors at Fukushima, and they blow up due to a steam explosion, they could spread significant amounts of cobalt-60 all over Japan, along with uranium, plutonium, caesium-137 and iodine-131.

Cobalt-60 is most dangerous though, because it's particles are very light and can be carried longer distances by the wind. All you need is a few grams distributed in small particles per square kilometer and it'll be a mess for hundreds of years. Uranium and plutonium will probably not make it far outside 100km of the plant by wind though, they are too heavy.