[upcountryhorseman]

If the containment vessel is cracked or damaged, there will
be a meltdown because coolant water will leak out and not
cover the fuel rods.

[lepton]

If the containment vessel is cracked or damaged, there will be a meltdown

One of the key things here is what is meant by "meltdown". "Melting" is not the same as meltdown, and "meltdown" is a whole range of things. Which one do you mean?