The level of radiation that nuclear reactors can produce is staggering. That's what makes them good at heating water. It takes a lot of shielding to protect people from that. Even a reactor that is "shut down" produces a good amount of radiation for weeks. The fuel cells continue to make heat almost indefinitely. If they are kept cool then no problem. But if they are not kept cool they will heat up and keep on heating up until they melt and then you could have concentration of the fuel, which then could cause an explosion or do the China Syndrome thing.
Along the way, if nuclear material is spread around, by explosions or leaking primary coolant from the reactor, then you have another problem. Everything that water touches becomes contaminated and it can spread radiation even further.
Scientists are already detecting increased Iodine-131 levels on both coasts in the US. You can run but you can't hide. Its here.
The only thing that suits do is protect you from contamination, not radiation.












