Of course they will. Uranium decays slowly by emitting an alpha particle. The half-life of uranium- 238 is about 4.47 billion years. Now thta is only the half life so you will have to wait about four times that to get to 1/16th life to be safe.
This may sound like a joke, but honestly why not dump a hydrogen bomb on the nuke sites and turn everything into glass? Serious question. Im not a scientist and yes, the entire Japan would be affected, but it could eliminate much of the radiation that would come out of it.
Sounds like that would send tons of radioactive material all over the place.
What I don't understand how they manage to lose reactors that were cool and not operational when the quake hit. It's like they couldn't do a worse job even if they were actually sabotaging the site themselves.
Japan would be suffering rolling blackouts for several years until new power could be brought online. The economic cost would be devastating. They probably tried to salvage, and waited too long. People never want to believe their eyes when the damage is this severe and this vital to their recovery.