Wednesday, May 25, 2011
Speaking of Doom
Regarding that Fukushima Daiichi incident - I was castigated the week after the disaster by a commenter who apparently thought I didn't know what I was writing about. Well, I can't say that I did know, but years ago when I had to work on business continuity plans for banks with nuclear plant exposures, I realized that nothing out there was adequate. So at that time I sat down and read through a bunch of NRC studies, figuring that NRC DID know.
So my comments were really based on NRC work, and as it turns out, NRC is quite good at what they do. I find this somewhat reassuring, although I wish we didn't have the proof. The evidence of which can be found in TEPCO's last analysis of the reactor states, which can be found at JAIF. Here is the latest one, which contains:
The operator of the troubled Fukushima Daiichi nuclear power plant says data analyses suggest that damage to its reactors may have caused holes inside them of up to 10 centimeters across.I sat down about a week ago with the records of water injection rates, and calculated some rough aperture estimates myself. I came out somewhat lower, but I am pretty sure that these are the data calculations TEPCO is relying on.
Reactors 1 through 3 at the plant suffered nuclear fuel meltdowns after the March 11th earthquake and tsunami. This is likely to have created holes and cracks at the bottom of the pressure vessels protecting the reactor cores and damaged the containment vessels.
Massive amounts of highly radioactive water also leaked from the structures. Tokyo Electric Power Company analyzed the changes in pressure levels inside the pressure and containment vessels after the quake to gauge the scope of the damage.
TEPCO said the analyses show that a hole 3 centimeters across may have been created at the containment vessel of the Number One reactor 18 hours after the quake. It added that a hole as large as 7 centimeters across is also likely to have been created at least 50 hours after the quake.
It also said a hole about 10 centimeters across may have been created in the containment vessel of the Number 2 reactor about 21 hours after the quake. It said that after the sound of an explosion was heard from the suppression pool of the Number 2 reactor on March 15th, a hole as large as 10 centimeters across may have been created there.
TEPCO said these results were obtained through data calculations, and that it has yet to confirm whether such holes actually exist.
Their plan to fix reactor 2 includes digging up the suppression chamber and grouting all around it. They are testing a compound in their lab.
Another fact which has emerged is that SPEEDI did a very good job indeed of predicting radiation dispersion.
As far as Hoenig goes, his resignation
might have shaken the political establishment.
Staying around to be the lone no vote doesn't
mean much. The situation is too serious for
talk without action from those in power.
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