How is that different from the accident point of view. They're both quite radioactive and both sit in deep pools of water.

The water in a nuclear waste storage pool should not be particularly radioactive unless something has gone wrong and contains mostly regular H2O.

The reactor vessel can contain heavy water or water with boric acid in it, neither of which are good for you. Additionally, neutron radiation from the reactor will cause the formation of radioactive tritium in the vessel water, so the liquid itself becomes radioactive.