Japan Earthquake: nuclear plants


by gmax137
Tags: earthquake, japan, nuclear
jim hardy
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#12943
Apr22-12, 02:26 PM
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Yet, in na'r an official document can you find reference to the explosion in unit 3, without being told implicitly that nothing but the possibility of a hydrogen explosion --an 'ex-ex-vessel' hydrogen explosion so to speak -- in the upper floors of the building has been found worth considering, but really hasn't, while it is all just 'believed to be' or 'assumed to be' what happened, nothing more, nothing less, and nothing is learned.
Are you hinting that what has not been said might speak volumes?

When the cameras get to the area of PCV flange then on to RPV upper and lower heads it'll end a lot of speculation.
SpunkyMonkey
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#12944
Apr22-12, 02:30 PM
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Quote Quote by westfield View Post
Spunky & Madder I may be wrong but I'm fairly sure that once you get past roughly halfway into the plug penetration it transitions from square opening to round - so there are likely no corners \ floor \ walls once you are in there at the PCV hatch.
Notice at the last corner before the slime trail, the wall looks pretty flat. But maybe you're right and it goes to a circular passage there, I'm not 100% sure either way.

Update: consistent with your theory, I think the slime trail may be seen to curve upward in the first frames where we get a quick look down its length. Or that might be camera 'fish-bowl' distortion.

I may be wrong again but these do look quite like a PCV hatch and flange.
Looking Straight at hatch, along "wall" at hatch. across hatch to wall ---
I'm tempted to agree, and as such in viewing the 'hotspot' we're not really looking at a new place. I'm thinking maybe the burst of ccd snow is caused by the camera being closer to an unvisualized floor were highly contaminated water has pooled. That burst of snow has to mean something unique me thinks.
MadderDoc
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#12945
Apr22-12, 05:12 PM
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Gentlemen, it is such a pleasure working with you. On reviewing the video using autogain, as inspired by Spunky's wonderfully improved video, and using westfield's directives along the route, I get the timeline below of the camera position relative to landmarks of the cavity wall.

Position A is at the outside wall of the concrete shield, B is at the first notch on the wall, C is a small notch in the wall which I would think is close to as far as the plug goes, when it is fully inserted. Behind C and deeper into the void, we are inside the room that was behind the plug in its normal position. At D not far from C, the room seems to narrow in considerably, which might mean we are now inside the cylindrical part of the hatch construction, and we could potentially now be seeing the lid of the hatch at some time during the approximately 2 minute sequence which follows, until the camera finally exits.

Entry times:
A: 0:54.4
B: 0:58.4
C: 1.07.8
D: 1.09.0

Exit times
D: 3:05.3
C: 3:08.0
B: 3:19.0
A: 3:31.2

To westfield: I suggest there might be a bottom insert in the metal portion of the hatch, such as to produce a horizontal floor inside it. I imagine that could be practical for equipment loading and unloading through the hatch, and the previously posted photo from that METI/industry document of an open hatch seen from inside of the PCV appears to have such an insert.

To Spunky: looking at these streaking particles, there are times I get this weird impression that they move as being taken by a wind, is it only my brain doing this, is it some kind of illusion, or is there a draught at the floor in that room?

To both of you: Could that yucky rusty patch be on such presumed horizontal floor inside the metal portion of the hatch?. I can't get away from Tepco's statement that the water is seen on a floor.
MadderDoc
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#12946
Apr23-12, 05:08 AM
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Quote Quote by jim hardy View Post
Are you hinting that what has not been said might speak volumes?
In a way, maybe, similar to the curious incident of the dog (it didn't bark), in the short story Silver Blaze.

("Is there any point to which you would wish to draw my attention?" "To the curious incident of the dog in the night-time." "The dog did nothing in the night-time." "That was the curious incident," remarked Sherlock Holmes.)

When the cameras get to the area of PCV flange then on to RPV upper and lower heads it'll end a lot of speculation.
Well there's some way to go to get there yet, but they do seem to be building a platform, which could be suitable for such attempts.

(photo cropped from: http://www.sdnyw.cn/news/edit/Upload...1292418951.jpg)

The photo above, btw, establishes certainty about what is the dark shape we have seen in poorer photos, at the east side of the equipment pool, at the close end to the reactor area. It is not anything but a big hole in the fifth floor, apparently blown upwards from below. Previous photos from above would then suggest that the damage below goes as far as to the 3rd floor. The hole in the floor would seem to be a likely candidate for the apparent source of the black smoke event on March 21st, one week after the explosion. No close up photos have been published of the possibly related black smoke event on March 23rd
MadderDoc
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#12947
Apr23-12, 05:35 AM
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Quote Quote by MadderDoc View Post
<..>Could that yucky rusty patch be on such presumed horizontal floor inside the metal portion of the hatch?. I can't get away from Tepco's statement that the water is seen on a floor.
I've thought about, looked a bit more on this video, and perhaps the indications of Tepco matters less as regards which surface this water is seen, than as regards which type of damage is indicated. I may have just got a false impression of what Tepco intended to convey. Although I am still not quite sure what I see in the video, it seems a far cry from just a puddle in some rails, or a leaking gasket. I do understand the video might have given some pause for thought.
MadderDoc
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#12948
Apr23-12, 07:05 AM
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Quote Quote by biggerten View Post
You make a valid point. But how do you eat an elephant? One bite at a time.
Yeah, always. But how do you roach it.... :-)

OK, water-filling to the fifth floor of these tormented structures. Plan B?
SteveElbows
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#12949
Apr23-12, 07:54 AM
P: 630
For now I'm keeping an open mind on the reactor 3 equipment hatch video, since issues of scale as well as orientation play tricks on me.

Meanwhile there are a couple of good images of people visiting the upper floor of reactor 4 here, including the covered fuel pool and a view of the top of the reactor well.

http://photo.tepco.co.jp/library/120.../120423_03.jpg

http://photo.tepco.co.jp/library/120.../120423_04.jpg
SteveElbows
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#12950
Apr23-12, 08:00 AM
P: 630
Quote Quote by MadderDoc View Post
The photo above, btw, establishes certainty about what is the dark shape we have seen in poorer photos, at the east side of the equipment pool, at the close end to the reactor area. It is not anything but a big hole in the fifth floor, apparently blown upwards from below. Previous photos from above would then suggest that the damage below goes as far as to the 3rd floor.
The thing that was described a long time ago as 'snaggle tooth' and that I spent a while on debunking the idea that it was the top of containment?

From that photo Im not sure as it is a hole, it could be, but it could also be something that has melted/burnt. I believe there is a little bit of melted black substance hanging off the roof beams that are above this area, not sure if its related.

As for whether it has anything to do with the black smoke event, it might, but there isn't much that lets us take this idea much further.

edited to add picture where black stuff on roof beam can be made out.
Attached Thumbnails
reactor3blackstuff.jpg  
Rive
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#12951
Apr23-12, 08:09 AM
P: 337
Quote Quote by MadderDoc View Post
... a big hole in the fifth floor, apparently blown upwards from below. Previous photos from above would then suggest that the damage below goes as far as to the 3rd floor.
We have some floorplans from U2 survey maps, so maybe we can find out something about the affected areas.
westfield
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#12952
Apr23-12, 08:27 AM
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Quote Quote by MadderDoc View Post

<snip>


To westfield: I suggest there might be a bottom insert in the metal portion of the hatch, such as to produce a horizontal floor inside it. I imagine that could be practical for equipment loading and unloading through the hatch, and the previously posted photo from that METI/industry document of an open hatch seen from inside of the PCV appears to have such an insert.

<snip>

To both of you: Could that yucky rusty patch be on such presumed horizontal floor inside the metal portion of the hatch?. I can't get away from Tepco's statement that the water is seen on a floor.
When any of these PCV hatches are open I would be very surprised if there was not always some sort of cover to protect at least the seal seat on the flange if not the whole flange from damage and as you say, to make the hatch trafficable. We see such "bridges" in the Browns Ferry & the Onagawa equipment hatch images and in those it's clear the "bridges" would be removed when the PCV hatch is closed out.

Additionally, I don't think anything loose at all would be left in the shield plug void and I don't think there would be anything permanent that might tie or create possible interference with the concrete \ steel interface at operational temperatures.

So I'm only guessing but personally I wouldn't think there would be any sort of "step" mounted in the equipment hatch flange itself or near it.


I've been reading about Onagawa NPP damage due to earthquake only. Quite eye opening.
Amongst that there is this ( taken from this report )

Onagawa PCV equipment hatch shield plug


How much it broke it's lock and moved


Shield plug movement mystery solved?
HowlerMonkey
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#12953
Apr23-12, 09:20 AM
P: 275
Lots of combustible materials outside containment but within the buildings.
jim hardy
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#12954
Apr23-12, 09:30 AM
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the dark shape we have seen in poorer photos,
great images guys, guess i haven't been keeping up.


"Snaggletooth" was a shadowy apparition in several early photos. i've seen no further hints of him since March last year.

old jim
westfield
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#12955
Apr23-12, 10:13 AM
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Quote Quote by SteveElbows View Post
The thing that was described a long time ago as 'snaggle tooth' and that I spent a while on debunking the idea that it was the top of containment?

From that photo Im not sure as it is a hole, it could be, but it could also be something that has melted/burnt. I believe there is a little bit of melted black substance hanging off the roof beams that are above this area, not sure if its related.

As for whether it has anything to do with the black smoke event, it might, but there isn't much that lets us take this idea much further.

edited to add picture where black stuff on roof beam can be made out.
Quote Quote by MadderDoc View Post

<snip>


Well there's some way to go to get there yet, but they do seem to be building a platform, which could be suitable for such attempts.

<snip>


The photo above, btw, establishes certainty about what is the dark shape we have seen in poorer photos, at the east side of the equipment pool, at the close end to the reactor area. It is not anything but a big hole in the fifth floor, apparently blown upwards from below. Previous photos from above would then suggest that the damage below goes as far as to the 3rd floor. <snip>
Is that one of the platforms for the demolition work in your previous post?

You mean this hole in the floor adjacent to the DS pit was uncertain? ;) (March 30 2012 image)




Steve what was the date for the "black smoke" event? As you also noticed on aerial shots sometime between the March 20th and the 24th the roof truss directly over that hole seems to have taken on a sooty appearance. Edit : I'm not referring to the black sheet of roofing membrane or whatever it is.

Around March 20th 2011, Around Mar 23 and then Mar 30.



Re damage in U3 - if you watch the recent PCV equipment hatch clip there are several glimpses of more significant disarray on FL 1 than we have seen before. It's not so tidy down there. The reason I mention that in relation to the hole in FL5 floor is I was reading an interesting report last night that included some modeling of the U3 hydrogen dispersion and subsequent deflagration. That particular modeling placed the ignition source on 1FL of U3. I will try to find the link. I didn't bother at the time because I thought it would have been posted here already. It seemed quite authoritive. It was a reprt from Nisa or METI or someone like that.Is that modelling and the first floor ignition point something new?
MadderDoc
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#12956
Apr23-12, 10:24 AM
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Quote Quote by SteveElbows View Post
The thing that was described a long time ago as 'snaggle tooth' and that I spent a while on debunking the idea that it was the top of containment?

From that photo Im not sure as it is a hole, it could be, but it could also be something that has melted/burnt.
Yes, that was a fair alternative explanation. What finally clinches it for me as a hole is that in the new photo I can now clearly see the bent up rebar at the far side. But already the previous best photo of the location I felt strongly suggested a hole:

(crop, color-releveled & de-distorted, from http://photo.tepco.co.jp/library/111008_1/111008_05.jpg )

I believe there is a little bit of melted black substance hanging off the roof beams that are above this area, not sure if its related.

As for whether it has anything to do with the black smoke event, it might, but there isn't much that lets us take this idea much further.<..>
Oh Steve! We can do better, we can put to rest that idea once and for all :-)
The black substance was there on those roof beams with a quite similar attire in photos from the day before the first black smoke event, so it had nothing to do with any of those.

It appears to be some flexible material, and has always had a weird 'green-metallic' look. I have no idea how it got there, but would assume it came there as a result of the explosion. It can be fairly hypothesised, seeing the way it has been apparently closely draped around the beams that it may have been shaped by heat influence, either from landing there while the beams were still hot after the explosion, or from the heat influence of the massive amounts of steam that came out of the primary containment vessel during the first couple of days after the explosion.
MadderDoc
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#12957
Apr23-12, 10:29 AM
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Quote Quote by westfield View Post
<..>Is that modelling and the first floor ignition point something new?
It is to me, at least (drool).
westfield
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#12958
Apr23-12, 10:36 AM
P: 143
Quote Quote by MadderDoc View Post
It is to me, at least (drool).
ok I will trawl through my browser history and try to find the link.
Don't ruin your shirt though, it was only a one or two page summary of the modelling in amongst a lot of other summaries.

Edit : While I look for that- I don't know if this report has been posted.
I had always wondered what happened to the roller door of the Unit 3 TB.

This emergency response report has lots of interesting details of the immediate on site actions that I'd never read in other reports, such as why they drove a truck through the Turbine Building roller door.

Edit Edit : Holy C*** - what are the odds two people would post a link to the same report at virtually the same time!!!
MadderDoc
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#12959
Apr23-12, 10:41 AM
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Perhaps relevant to some of the current topics of discussion:
(from http://icanps.go.jp/eng/120224Honbun04Eng.pdf )

"At around 14:31 that day [March 13th 2011], a high radiation level of more than 300 mSv/h was detected north of the double-entry door of the Unit 3 R/B, white haze was observed inside the double-entry door and a level of 100 mSv/h was detected south of the double-entry door."

" Since white haze filled the first floor of the Unit 3
R/B and their APDs showed high readings at that time, they evacuated from the building."
MadderDoc
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#12960
Apr23-12, 10:49 AM
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Quote Quote by westfield View Post
ok I will trawl through my browser history and try to find the link.
Don't ruin your shirt though, it was only a one or two page summary of the modelling in amongst a lot of other summaries.
Well, I'll be happy to read it if you can find it without too much trouble. Whereas there are signs of damage just about anywhere of unit 3, this damage seems to me to be centered about the 3rd,4th and 5th floor, and the primary containment. Hum. Perhaps centered is not the right word for such widespread destruction. Anyhow, not particularly centered about the 1st floor.


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