Thanks. I am just a layperson too, who had a very large amount of time to pay attention to this disaster in the first years, and who always enjoyed talking here about it 10+ years ago with knowledgable and inquisitive people. And now its only in recent years that they reached the point of site...
By the way, after quite a number of years of not paying as much attention as I did in the first years after the disaster, I found it rather tedious trying to search for the English versions of TEPCO documents that come out these days, due to changes in how their website is organised. Sometimes...
Thanks for that update. The DebrisWiki site is useful. They also review their understanding of core damage and accident progression on that site. As we already know from past stuff such as the missing concrete in unit 1, there is an assumption of plenty of MCCI there. And just like in the report...
Thanks so much for drawing attention to this document and explaining it.
Are they saying that a fuel bundle handle is shown in one of those photos? Certainly an object that shape is rather the star of one of the photos in that document. If so its certainly the most interesting 'corium' type...
The following english pdf has radiation measurements of the water. Since years have gone by since I learned something about how to interpret the scale of such readings, and I've gone really rusty on this front in the meantime, would anybody be so kind as to say something about these numbers and...
Here is the version in english:
http://www.tepco.co.jp/en/nu/fukushima-np/handouts/2016/images/handouts_160526_01-e.pdf
And here is the much older 2015 document that drew conclusions about unit 1 using that technique...
I thought the X-6 penetration decontamination attempts looked like something of a failure in that document. And indeed I just noticed that TEPCO made an English press release in late January that admitted there would be a delay...
What you may need to keep in mind is that this is a physics forum. As such there is a low tolerance towards various forms of discussion about Fukushima that veer to far away from the scientific method.
As I understand it there was more slack given to the main Fukushima thread than would often...
Well as radiation survey maps from previous years showed the same pattern, this stuff has been discussed before.
I don't have the most detailed studies to hand, but here is a rough description of relevant info:
Wind direction was out to sea at several stages, including the explosion of...
A lot of the December 13th documents that still say 'to be translated' on the TEPCO page have actually been translated already, and are available in english by clicking the links. There are only a few exceptions.
Perhaps I should mention that another, much longer, document came out on the same date, I assume exploring the same topics in more technical detail. But as my attempts to machine-translate it have given very poor results, I haven't tried to work out if there is anything of note in it...
The acknowledgment of these things also has implications for TEPCOs own analysis of things like core melt. It allows them to update such stuff to be somewhat more credible. I certainly spent a while complaining about their analysis in the past, and one of my complaints was the rather optimistic...
I'd need to go back and check. All the same I think they think reactor 3 venting did eventually happen via the stack. Obviously another problem they had was a lack of stack instrument functionality due to power failure, so they were using crude methods such as checking the webcam for evidence of...
All this talk of rupture disc problems runs the risk of downplaying the other issues that delayed venting, and also runs the risk of making it sound like venting failed at all the reactors, as opposed to the apparent reality that it was mostly reactor 2 where the failure to vent story was...
I believe we need a lot more detailed mappings of radiation levels at a wide range of locations in the reactor 1 torus room. Especially since there is quite a large disparity between the first set of 'probe dangled on a wire' radiation readings at different heights within the reactor 1 torus...