What I dont understand is the way we build nuclear plants - why are they not built in very large pits, with huge silos that hold a concrete slurry mix that can

What I dont understand is the way we build nuclear plants - why are they not built in very large pits, with huge silos that hold a concrete slurry mix that can be realeased to flood the pit and encase the whole thing in concrete should the need arise. http://en.wikipedia.org/wiki/Bingham_Canyon_Mine http://en.wikipedia.org/wiki/Bingham_Canyon_Mine Put it in the base of this pit - and create a way to encase it if needed.