[chimera]

My guess is that there will probably be some procedural changes as to how much fuel can be in the SPF at any one time. Unit 4 had a full core offload, which adds significantly to the heat load, as well as some older fuel. There will probably be some rule making to the effect that older fuel should be removed to the common storage pool, for those facilities that have such features.

It is not clear to me at this point if the Unit 4 SPF has been significantly damaged. There was some concern that there was fuel damage resulting from overheating when they lost the SPF cooling capabilities, or perhaps from debris falling onto the fuel from the damage to the roof and overhead crane when they had their hydrogen detonation. The pictures I've seen taken from above show a lot of debris and it is difficult to get a clear look. Until there is a close-up inspection it is all guesswork.

[bvw]

It’s clear that the pits and the medium term storage of the spent fuel could use some major re-engineering to reduce event risks (1) during re-fueling and (2) during regular operations.