You can walk through the chernobyl exclusion zone and get no significant extra rads whatsoever as long as you stick to paths and roads which have been checked - the radiative contanimation doesnt just blanket the place, it is spotty, and the fukushima zone got hit much less hard, so industrializing the heck out of the place- for whatever purpose- is not going to negatively affect the workers as long as you go over the place with a geiger counter first. Given the value of japanese land, I sort of expect the exclusion zone to get turned into a series of disconnected exclusion hotspots after people go over the entire area in a fine grid with geiger counters. If that doesnt happen because of paranoia, making it an energy park makes a lot of sense.