This is kind of what they were worried about, the spent fuel pools need to also be kept cool by pumped water and the difference is that they aren’t in a containment vessel.
Precisely the problem. Two huge holes in the building. Apparently the explosions and other chaos caused them to stop monitoring the spent fuel rod tanks in #4. Now reports are that #5 and #6 pools are heating. This plant was really a dumb idea and that dumb idea was compounded by not being able to find a safe permanent storage facility for the spent fuel rods far away from any live reactors. This is the folly of man.