I am speculating with limited data and a whole hell of a lot of hindsight it is clear to me that many design flaws were built into these designs and being 40 year old plants is no excuse. The fact that all ten emergency generators were at or a little below ground level and were protected by a protection wall high enough to hold back Tsunami force waves and the switchgear to connect them to the plant were behind that wall looks like piss poor planning to me.. The largest wave ever experienced in the area was a 50 footer in 1896 they did not prepare for one that size.. A prudent engineer would have added at least 50 percent more wall just for the hell of it.. Just this one lack of judgement probably put them in this position..
Some are saying today that the plants on the design tables now would have survived this disaster.. That use to sit really well with me but with this incident I will question further designs.. That we pretend to be able to guess the maximum quake strength on any fault has proven to be bullshit time and time again. So what's a good engineer to do.. There most likely is not a design that you can absolutely guarantee will not fail.. You can guarantee it, but who is going to believe it..
The bottom line is a real bitch.. The trade off is as , Don't build them and millions will die from lack of power to sustain modern day life.. or build them and take the chance some will die in a major meltdown ... I'm putting my money on building them.... what am I using to come to this conclusion ..45 years of safe naval reactor operations and with the exception of 3 mile island , a 104 , 40 year plant operating history that has been the safest in comparison to any other major energy fuel..
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