In what world are you living that you not have heard about nuclear accidents? Here is a reading list for you:
https://en.wikipedia.org/wiki/Windscale_fire
https://en.wikipedia.org/wiki/Three_Mile_Island_accident
https://en.wikipedia.org/wiki/Chernobyl_disaster
https://en.wikipedia.org/wiki/Fukushima_nuclear_accident
With regard to nuclear waste. Here is an example, how it can went quickly out of control:
Yes I have and you clearly know nothing about those incidents else you wouldn't give a laundry list of wikipedia article you haven't even read.