The only nuclear accident that has killed any significant number of people was Chernobyl: which used the most dangerous reactor design that had ever existed, had tons of corners cut, was being operated by barely-trained staff, and the safeties were turned off temporarily. This was the Soviet Union, where failure could end in the manager's imprisonment in the GULAG or even death. As a result, it was not exactly run properly...

Today, Pripyat is perfectly safe except for the immediate vicinity of the reactor. People could live there.