Molten salt reactors have the ability to avoid such disasters, as a built-in design criterion. In such a reactor there's no issue if the fuel melts down, it's n

Molten salt reactors have the ability to avoid such disasters, as a built-in design criterion. In such a reactor there's no issue if the fuel melts down, it's normally molten anyway. If there's a loss of coolant then the core melts through a frozen salt plug and then sits in a catch area. Because the core isn't under high pressures there's vastly less risk of any radioactive bits escaping the confines of the reactor.