And given the Japanese architectural engineering prowess on display from all the video abounding showing how little structual damage occured despite the intense shaking of a very violent earthquake, them pressure containment vessels could withstand a direct hit of a small nuke right now and retain pressure integrity AFAIC.
There's no way any meltage of the core occured. There is undoubtedly deformation of the fuel and moderator rod assembly, i.e., warpage due to unmitigated intense heat of the nuclear pile while it was uncovered for a short time (as the coolant bled off).
Even so, the nuclear pile was never totally uncooled. Even IF the entire nuclear pile was only in contact with steam, the steam was still exchanging heat from the nuclear pile into the secondary torus water reervoir; all that's part of the calculated cooling design specs (albeit not optimal but within putative tolerances ostensibly to avoid outright core meltdown).
In fact, even in the Sci-Fi event the reactor core did melt in entirety, the secondary containment vessel is designed and constructed such that the molten slag of the entire nuclear core would be confined entirely within the secondary torus water reservoir (resting upon a graphite floor a meter thick acting as moderator). It might take a decade for that to cool, but there'd be no catastrophe.
There's no way for un-enriched fuel to go critical, and the graphite - along with the incorporated molten moderating rod material - would dampen over time whatever residual reaction was still occuring.
Thank you for the clarification.
the steam was still exchanging heat from the nuclear pile into the secondary torus water reservoir
I'm thinking that with a 9.1 earthquake and a 10 meter tsunami, it is possible that the torus in several of the reactors did shift. In the designs of these types of reactors, the torus is actually "floating" in the basement of the reactor.........When reactor #1 exploded topside, there were 4 workers in the basement who were injured. I'm thinking that they were monitoring the leaks down there........
Anyway, the main problem at these reactors has been the continual loss of cooling water.......
Something else that very few are talking about is the "spent fuel pool" where decades of spent fuel are housed in something similar to a swimming pool (open on top)............in the reactors in trouble right now in Japan, I believe all of them have the spent fuel pools stationed above the reactor. Once they have a loss of water and are exposed to the air, there is the potential for very serious problems............My hope is that the hydrogen venting explosions that occurred at #1 and #3 did not compromise the pools that hold the still radioactive fuel that could possibly catch fire, etc...........
No Chicken Little here, just using Free Republic as it is meant to be used, for information and discussion.........
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