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Borek
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causeceleb said:then you are saying that TEPCO is saying that there is next to zero radioactivity (these three isotopes) at the main gate?
No, I am just explaining what the result means.
causeceleb said:then you are saying that TEPCO is saying that there is next to zero radioactivity (these three isotopes) at the main gate?
SteveElbows said:The following document, which I have mentioned at least once before in this thread and which is in Japanese, seems to contain a wealth of information about how they estimate contamination, far more than we usually get. Its from an NSC meeting (meeting 31). Computer translation does not do a perfect job of revealing the details in their full glory, but give it a try and you should at least see what I mean. There are a few tables and charts there too which require almost no translation to understand. And the one on the very last page shows a timeline of release magnitude which really helps to get a sense of the picture they have established when collecting data and doing their analysis of what happened.
http://www.nsc.go.jp/anzen/shidai/genan2011/genan031/siryo4-2.pdf
Borek said:No, I am just explaining what the result means.
elektrownik said:Yes but this new water injection system is almost the same as concrede pump, so this shouldn't act on sst water level
interesting data and photos from today about unit 4:
http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_110630_03-e.pdf
clancy688 said:Big thanks! The graph is interesting indeed.
There was a MAJOR C137 release going on for at least one day between March 30th and 31st. 100 TBq/h, makes 2400 TBq C137. Converted value: 96.000 TBq, over 10% of the total number. That alone would be sufficient for an INES 7 classification. What happened that day?
Or is this a mistake on my part, did I read the chart wrong?
In case it's real: Then screw my previous comments about airborne releases and the number not rising anymore - in that case, those are wrong of course.
Bodge said:The CTBTO monitoring is back.
I find the I-131 peaks to be indicative of ongoing fission somewhere on the site.
SteveElbows said:I am fairly sure their estimated total releases covers the entire period shown in that graph, so their figure of 630,000 TBq covers the includes the end of March figure you mention. Actually this document also shows that they slightly revised upwards their calculation for total release of Caesium. Using INES conversion I think the new NSC-calculated total release for period up to 6th April was 670,000 TBq. Crucially I don't think any high magnitude releases beyond the dates covered by this report have been mentioned, so I believe your point that later daily releases don't make very much difference to the estimated total is still valid.
SteveElbows said:I don't think you are reading the chart wrong,but due to a lack of official narrative about air release events past the first week, I cannot really tell you what happened on that day, but I do intend to look into it further again sometime. It was the even higher magnitude release estimated for a time on March 15th that got most of my attention when I first found this document.
As for the number not rising significantly anymore, using computer translation of that NSC document I am fairly sure their estimated total releases covers the entire period shown in that graph, so their figure of 630,000 TBq covers the includes the end of March figure you mention. Actually this document also shows that they slightly revised upwards their calculation for total release of Caesium. Using INES conversion I think the new NSC-calculated total release for period up to 6th April was 670,000 TBq. Crucially I don't think any high magnitude releases beyond the dates covered by this report have been mentioned, so I believe your point that later daily releases don't make very much difference to the estimated total is still valid.
tsutsuji said:The daily Kurion-Areva facility trouble :
http://sankei.jp.msn.com/affairs/news/110630/dst11063022440037-n1.htm (and http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_110630_05-e.pdf ) : On 30 June the decontamination facility was stopped for flushing between 10:46 AM and 1:35 PM. The facility was restarted but after one hour it had to stop again because of an alarm signalling that gasses are unable to evacuate through the exhaust stack at the Areva facility.
http://www.nikkei.com/news/headline...19481E1E2E2E19A8DE1E2E2E4E0E2E3E39797E0E2E2E3 The facility started again at 6:50 PM (30 June).
elektrownik said:Yes but this new water injection system is almost the same as concrede pump, so this shouldn't act on sst water level
interesting data and photos from today about unit 4:
http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_110630_03-e.pdf
Bodge said:The CTBTO monitoring is back.
I find the I-131 peaks to be indicative of ongoing fission somewhere on the site.
[PLAIN]http://www.bfs.de/de/ion/imis/ctbto_aktivitaetskonzentrationen_jod.gif
[PLAIN]http://www.bfs.de/de/ion/imis/ctbto_aktivitaetskonzentrationen_caesium.gif
MiceAndMen said:Hallelujah we finally have an official TEPCO diagram for the refueling floor at unit 4. Very interesting pictures. How very strange to see the reactor well open to the sun and sky looking like a large swimming pool.elektrownik said:Yes but this new water injection system is almost the same as concrede pump, so this shouldn't act on sst water level
interesting data and photos from today about unit 4:
http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_110630_03-e.pdf
joewein said:I am attaching horizontal views of Fukushima 1 unit 1, looking north and looking west. Units 2-5 are somewhat different, but it should still be a useful reference.
causeceleb said:how can there be no new Iodine-131 when there is
800 tons of corium laying about all over the place
at Fukushima Daiichi?
MiceAndMen said:In the same pdf, I'm having trouble placing the bottom left photo with regards to where the camera was positioned and which way it is pointing. The caption may be wrong as well.
SteveElbows said:The caption isn't brilliant, but I have some sense of where this photo is taken, due to the yellow containment cap location which we know well.
Camera is pointing North, so equipment pit is in the far distance. Reactor well is just in front of cameraman, and cameraman could probably have shot the next photo of the reactor well without moving, just by pointing camera down and to the right somewhat. This may not be what actually happened, as reactor well photo may have ben taken from opposite side, I am just trying to illustrate what I believe to be the camera position relative to reactor well in the photo you mention.
joewein said:Unit 1 contained 68 t of fuel while units 2 and 3 contained 94 t each. Therefore, assuming their cores completely melted, the amount of corium should be roughly a third of the figure you gave.
Corium is not only made of melted fuel but also incorporates control rods, melted steel from RPV, rods support assembly and probably a lot of other "stuff" like pipes, bolts... If 100% or each core has melted through RPV, total corium weight might be initially around 260 T (Fuel) + all other stuff surrounding that "hot affair".joewein said:ITherefore, assuming their cores completely melted, the amount of corium should be roughly a third of the figure you gave.
joewein said:I think you got the direction right, but I believe it was taken just a few meters further south, perhaps next to the green "bridge" (which I presume is the "Fuel Exchange Truck", a crane).
When you look at the http://www.tepco.co.jp/en/news/110311/images/110701_1.jpg" and the right one showing the pool gate, while the middle one of the reactor well shows the rusty one.
I wish those two structures where shown on the floor map as the green one is.
Joe Neubarth said:Hence the radioactive Iodine spikes. Weather can not find a hidden reservoir of Iodine that it suddenly taps. I suppose Iodine can be concentrated in the mist in rain clouds, but was it raining from lingering rain clouds every time there was a spike? I don't think so.
Now select the TCb X Pc plot. http://www.ic.unicamp.br/~stolfi/EXPORT/projects/fukushima/plots/cur/out/ptmp-TCn-PCA-un3-full.png [/URL] That one's easy. The bottom of vessel has always been hot enough to boil the water in the vessel. Well except for a couple readings and it'd be logical they pushed their injection up to verify they could cool it. That would be smart for it'd positively rule out ongoing criticality and is something an egghead would think of. Or it could be just that they were getting the hang of controlling temperature with fire pumps. On second thought it would make real good sense to do that experiment given the press speculation about ongoing criticality and could be the basis they asserted in the press release about Neutron Beams "no criticality has occured."[/quote]
[url]http://tickerforum.org/akcs-www?post=182121&page=314[/url]
The south beam of the white crane structure is not visible in the middle photo because it is shot standing on it :-) towards the north and rusty beam.joewein said:I think you got the direction right, but I believe it was taken just a few meters further south, perhaps next to the green "bridge" (which I presume is the "Fuel Exchange Truck", a crane).
When you look at the http://www.tepco.co.jp/en/news/110311/images/110701_1.jpg" and the right one showing the pool gate, while the middle one of the reactor well shows the rusty one.
I wish those two structures where shown on the floor map as the green one is.
Joe Neubarth said:Guys, I think some of those spikes in Iodine were the results of some ongoing criticality somewhere in the Fukushima site.
Do you guys remember Arnie's "Breathing" comments on Reactor One? Do you remember the detection of Neutron Beams outside of the reactor buildings? I don't know that I ever saw a complete explanation about that. We probably never will get one either.
greenpharao said:According to the gamma radiation readings (CAMS) of Unit 1's Drywell B there is still a lot of on/off activity happening. I'm no scientist, but I think this data-graph speaks for itselves
Can anyone interpret these spikes?
I am not qualified to authoritatively speak to ongoing recriticality or its possible variants, but there are three pieces of evidence about that particular sensor (#1 CAM B):greenpharao said:According to the gamma radiation readings (CAMS) of Unit 1's Drywell B there is still a lot of on/off activity happening. I'm no scientist, but I think this data-graph speaks for itselves:
----------------------------------------
Can anyone interpret these spikes?
SteveElbows said:Here is another photo from their adventure on the refuelling floor at reactor 4:
http://www.tepco.co.jp/en/news/110311/images/110701_1.jpg
Finally a view of the spent fuel pool that puts much in perspective, including the large round area that is partially separated from the rest of the pool. We can now see why it has a square round it on diagrams.
SteveElbows said:Here is another photo from their adventure on the refuelling floor at reactor 4:
http://www.tepco.co.jp/en/news/110311/images/110701_1.jpg
Finally a view of the spent fuel pool that puts much in perspective, including the large round area that is partially separated from the rest of the pool. We can now see why it has a square round it on diagrams.
SteveElbows said:The caption isn't brilliant, but I have some sense of where this photo is taken, due to the yellow containment cap location which we know well.
Camera is pointing North, so equipment pit is in the far distance. Reactor well is just in front of cameraman, and cameraman could probably have shot the next photo of the reactor well without moving, just by pointing camera down and to the right somewhat. This may not be what actually happened, as reactor well photo may have ben taken from opposite side, I am just trying to illustrate what I believe to be the camera position relative to reactor well in the photo you mention.
It's hard to say what the whitish structures are. Obviously they've got cranes on them. My guess is they're special equipment needed for the core shroud replacement work, and wouldn't appear in the original blueprints at all. Regardless, they could have been drawn in overlaid on the floor plan, so I'm with you there. It would have made things clearer. I also have to go back and look at the pictures taken from the outside by the aerial survey and T-Hawk drones. I don't remember seeing the white bridge-crane support steel anywhere before these latest pictures.joewein said:I wish those two structures where shown on the floor map as the green one is.