Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[Pu239]

Well, I did find this explanation - for the Unit 4 vapour release of June 14 (Japan's June 14 - it was June 13 here in N America):

http://ex-skf.blogspot.com/2011/06/fukushima-i-nuke-plant-live-camera.html

The water in the spent fuel pool of the #4 reactor is not getting cooled as much as before because TEPCO is installing supports beneath the pool. If they squirt in more cold water from the top with the pumper, they spill radioactive water on the construction work.

So the pool is heating up, over 80 degrees C already last week and probably close to boiling now. That will sharply increase the volume of steam, especially so at night when the air is cooler.

 

[mscharisma]

Certain SPEEDI predictions, and off-site samples were clearly censored. This was all to do with evacuations and areas that had suffered the worst contamination.

And yes, in some other regards TEPCO were not exactly forthcoming with information.

However, when it comes to major events on site, and radiation data from site, their track record is not so bad. All I can really say is that there were numerous things they could have kept quiet about, but instead gave us some detail. Sure this does not tell me if they kept anything secret, but it does help me to make preliminary judgements when dealing with non-events that people think they saw on the webcam. TEPCO have had to issue denials based on webcam images at least once in the past, and explain about weather-related phenomenon. In that instance nothing really emerged that suggests they were lying, that anything of note happened. I expect the same this time, although there is always some chance I will be wrong.

"not exactly forthcoming" is somewhat of an oxymoron: either one tells it all or one doesn't. Maybe I'm too hard-nosed on this, but not telling it all makes just about anything questionable. Because there were things they could have kept quiet but didn't doesn't make anything they do release more reliable or conclusive. If I gambled away $1000 of your money, I can deny it completely, increasing the chance I get caught, or I can admit to $700 of it, giving the impression I'm forthcoming and honest, which I still am clearly not. Because of that, I am suggesting that what you called preliminary judgements are and remain indeed just that: preliminary judgements until all data is known and verified - by whoever one can trust these days.

 

[SteveElbows]

I am not sure which official information you are referring to. As you describe it, this information seems to say unambiguously that the panel was in place in the south wall of unit 2 until the explosion of unit 3 on March 14th -- leaving it only ambiguous whether the panel fell off due to that explosion, or whether it was actively removed, prompted by its occurrence. However, photographic evidence shows conclusively that the panel was not in place already by the morning of March 13th.

Thanks to people for pointing this out, I had forgotten about this photographic evidence. I cannot presently work out which official info I was referring to now, just spent ages fruitlessly searching, will try again later and post when I find it.

Indeed, quoting the report to the IAEA (my boldfacing):
"At around 6:00 on March 15, the sound of an impact was heard which was considered to have resulted from a hydrogen explosion. No visible damage was observed at the reactor building, but it was confirmed that the roof of the waste processing building which is neighboring to the reactor building was damaged. During these processes, radioactive material to be released into the environment, and as a result, the radiation dosage around the premises increased."

However, the photographic evidence supports _no progression_ of damage to the unit 2 neighbouring radiation waste building in connection with the explosion on March 15th in the unit 2 reactor building:
the roof of the unit 2 radiation waste building appears to have been damaged already in connection with the unit 1 explosion on March the 12th, and it does not appear to have suffered any further significant damage by later events.

I've not got photos with high enough resolution to see the roof properly from that time period, any chance you can point me to the image you mean?

In any case I've just been looking at their analysis again. TEPCO-2 is the analysis they picked to use for total radiation release estimates, so this is the scenario which generates the rather high estimates for reactor 2, the other reactor 2 analysis scenario tends to have the magnitude of release at around the same level as for reactors 1 & 3.

This version of events has core exposure at 18:00 March 14th and core damage at 19:50. TEPCO don't have RPV failure happening till 03:50 on March 16th, NISA have it at 22:50 on March 14th.

Damage to containment is clearly a part of this analysis case, as we would expect given its assumed environmental impact. In fact this TEPCO-2 analysis, along with one for reactor 1, is what generated a couple of headlines about possible size of containment holes. 50cm squared PCV leakage and 300 cm squared S/C leakage is assumed, and when using these numbers they are able to get the theoretical analysis data for things such as pressure to fit fairly well with actual pressure readings.

Anyway, good old attachment IV-2 ( http://www.kantei.go.jp/foreign/kan/topics/201106/pdf/attach_04_2.pdf ) provides the detail that I have discussed here, and when considering the nature of the release to the environment there are some especially handy graphs. On pages 35, 36 & 37, we can see how a variety of substances are expected to have been generated/released and changed location under this scenario. I note with special interest that the bulk of this seems to have happened prior to the explosion. See for example attached graphs that shows proportion of key substances and their locations, including wet well, reactor building, and crucially 'environment'. Any takers for what location FHB stands for in this context?

 

[SteveElbows]

Well, I did find this explanation - for the Unit 4 vapour release of June 14 (Japan's June 14 - it was June 13 here in N America):

http://ex-skf.blogspot.com/2011/06/fukushima-i-nuke-plant-live-camera.html

The water in the spent fuel pool of the #4 reactor is not getting cooled as much as before because TEPCO is installing supports beneath the pool. If they squirt in more cold water from the top with the pumper, they spill radioactive water on the construction work.

So the pool is heating up, over 80 degrees C already last week and probably close to boiling now. That will sharply increase the volume of steam, especially so at night when the air is cooler.

Its a misleading explanation. Temperature data that is now taken on a regular basis at 4 pool shows temperatures over 80 degrees C. But on the occasions in past months where they took temperature, and the reported temperature before the sensor went wrong in March, were also more than 80 degrees C. So there is no reason to think the pool is very much hotter now than it has been at any previous point since problems there began. Its much hotter than they are happy with, but its been that way for a long time.

As for the spraying, they sometimes go for days without spraying, and operations have continued in June much as before. They sprayed on the 3rd, 4th, 6th, 8th, and were due to spray on the 13th for many hours. That spraying event was due to finish at 21:00 on 13th but may have concluded a little earlier.

 

[~kujala~]

I did, and his reply was:

"I had a quick look at the report, and the geology (bed rock) is the grit (coarse sandstone) and siltstone, which is identical to the one I reported to you in my previous e-mail."

Thank you, sir(s)!

Somebody posted earlier some documents containing geological information of Fukushima. Also translations were provided. In that translation terms 'mudstone' and 'sandstone' were used. Also in an earthquake study of unit #6 the term 'mudstone' was used.

The problem with the word 'mustone' is that it is both a main category and a sub-category. When used as a main category it is also called 'mudrock' and it consists of several sub-categories which are: claystone, mudstone, siltstone, shale, slate.
http://en.wikipedia.org/wiki/Mudrock

So when it is said that bedrock consists of 'mudstone' I think it means that 'mudstone' is used as a main category. Actually the above would suggest that this 'mudstone' is 'siltstone' when going from the main category into the sub-category:

http://varasto.kerrostalo.huone.net/lietekivi_5.png

So from OP +0 m to OP -25 m it seems that 'siltstone' is the main rock category and there is a thinner layer of 'sandstone'. From OP +10 m to OP +0 m it's sand.

I have here a chart that contains the general strengths of different rock types. It's in Finnish but I can give some translations. 'Siltstone' is 'lietekivi' and it belongs to a category 25 - 50 Mpa. 'Sandstone' is 'hiekkakivi' and it belongs to a category 50 - 100 Mpa. Of course these are only general guidelines. 'Granite' is 'graniitti' and it's > 250 Mpa.

http://varasto.kerrostalo.huone.net/lietekivi_1.png

 

[Pu239]

Simple, let's check the wind direction and then look for any reports of radiation increases in the region where any fallout should have gone. I may take a few days but will allow us to discard this as a no-event, or maintain it in our list of "inconsistencies" between observations and reported data.

Good idea. I'm assuming a vapour release [almost always?] carries radiation with it in this situation?

Now, how to get a reliable set of data - obviously not from TEPCO (not picking on them, but I'm afraid credibility there really does approach zero - they're trying to manage things on several fronts).

The crowd-sourced radiation monitoring network(s?) might be more useful, even with cheaper equipment, if you do some kind of ad hoc averaging or trend analysis [I'm guessing]:

http://community.pachube.com/node/611
http://community.pachube.com/node/611#3d

 

[SteveElbows]

TEPCO on-site measurements provided useful information during the early chapters of the crisis, I see no reason at all to disregard such data now. I would be silly to use it as my only source, but right now it helps me lean strongly towards the recent web-cam events being of no significance.

http://www.tepco.co.jp/en/nu/fukushima-np/f1/images/f1-mp-2011061421-e.pdf

The later pages are more interesting. I don't think their weather observations in terms of 'fine', 'cloudy' etc are completely perfect, but bear in mind main gate is some way away from camera position. The wind data matches reasonably well with certain parts of what I recall seeing the sky doing on the camera in the early hours of 14th.

Fans of infuriating webcam weather confusion may also like to check out footage from around 6.30PM onwards where a cloud seems to be impersonating an interesting release from reactor 2, helped on by lighting conditions, the sped up nature of the footage, and the nature of clouds, the way they can 'bubble up'. http://www.youtube.com/user/fuku1live#p/u/8/kXIThbCBj-g

I never say never, but certainly the onus remains on people to demonstrate that anything interesting happened at all, so far we only have visual evidence for which alternative explanations are possible and seem likely, especially given what we have seen in the past on the camera.

 

[NUCENG]

In discussing releases from unit 2, if you accept that 90% of the offsite release is frim the unit which has a hole in its hat (reactor building) but the hat is still on its head. So you would expect that unit to be holding up some of the release in the building. There are reports that the internal radiation levels are too high for access, so they are working on filtering and venting the building which is consistent with it holding up releases. The reported failure was a hydrogen explosion thud in the torus area which depressurized the containment limiting the pressure to force further releases to the environment. (limiting not eliminating).

So here is the question. Does this mean that the unit 3 (which had the same power output as unit2) containment is still holding up most of its source term? With the tremendous damage to the unit 3 building any release from containment is directly to the environment.

 

[MadderDoc]

the roof of the unit 2 radiation waste building appears to have been damaged already in connection with the unit 1 explosion on March the 12th, and it does not appear to have suffered any further significant damage by later events.

I've not got photos with high enough resolution to see the roof properly from that time period, any chance you can point me to the image you mean?<..>

I am talking out of Digitalglobe's photo from March 14th 11:00. This is after the explosion of unit 1, but before the explosions in unit 2, 3, and 4. Although the quality is not A1, the photo appears to show the same damages to the roof of the RW building, as those we see in later and better imagery, e.g. the Air Service photo from March 20. Here's a side by side mount:

 

[SteveElbows]

So here is the question. Does this mean that the unit 3 (which had the same power output as unit2) containment is still holding up most of its source term? With the tremendous damage to the unit 3 building any release from containment is directly to the environment.

Well that's certainly one of the reasons I brought up the reactor 2 & INES release stuff.

In the analysis that this stuff was based on, they have supposed damage to containment on a scale necessary to make their analysis figures roughly match actual recorded data and other presumptions such as the explosion in s/c area at reactor 2. For reactors 1 & 2 they came up with containment damage of a certain size, but for reactor 3 their case seems to involve the possibility that HPCI had a steam leak. So I don't think they did an analysis where other sorts of containment damage featured for reactor 3, and I also don't think their analysis time period went long enough to cover later events at reactor 3.

Currently the matter of reactor 3 release is very inconclusive for me for those reasons and more, not least because the wind direction appears to have hugely reduced the impact certain key reactor 3 events may have had on the land, and presenting a theoretical opportunity to overlook a large release.

And if we are looking at the possibility that reactor 3 events with environmental impact occurred on the week of 20th march, data from this period is also hard to analyse with accuracy due in large part to further weather events that may have had an impact.

The very large order of magnitude of possible release from reactor 2 has tended to dwarf the numbers that follow, with implications even to this day since the large number of TBq released in March have made me a bit too desensitised to the 1TBq or so that is thought to perhaps be escaping on a daily basis to this day.

The attached chart from page 2 of the report to IAEA attachment VI-1 shows estimated magnitude of releases over time. It certainly tells the story of how events at reactor 2 contributed to matters according to the analysis. And also a few interesting tales of slightly lower magnitude later on, what happened on March 30th for example?

 

[Bandit127]

So here is the question. Does this mean that the unit 3 (which had the same power output as unit2) containment is still holding up most of its source term? With the tremendous damage to the unit 3 building any release from containment is directly to the environment.

Given the temperature of the RPV (>100°C) and pressure (~1 bar) readings from Unit 3 over the last month or so, I have to assume that this is a gas cooled reactor that is venting to open air.

No, I don't think it is holding up most of its source term. Gasses and gas borne particles have (mostly) already gone and the corium is still not in a configuartion that can be cooled.

So what source term is left is still mostly liquid and mobile.

I stand (and hope) to be corrected...

EDIT - we could have some data in the near future as TEPCO were sampling 'ambient radioactive substances' yesterday.
http://www.tepco.co.jp/en/news/110311/images/110614_23.jpg"

 

[MadderDoc]

<..>
http://www.tepco.co.jp/en/nu/fukushima-np/f1/images/f1-mp-2011061421-e.pdf

The later pages are more interesting. I don't think their weather observations in terms of 'fine', 'cloudy' etc are completely perfect, but bear in mind main gate is some way away from camera position. The wind data matches reasonably well with certain parts of what I recall seeing the sky doing on the camera in the early hours of 14th.

It may seem a silly question, but having looked at these data before, I never made it to decide whether "Wind direction" means the direction the wind is coming from, or the direction it is going?

Fans of infuriating webcam weather confusion may also like to check out footage from around 6.30PM onwards where a cloud seems to be impersonating an interesting release from reactor 2, helped on by lighting conditions, the sped up nature of the footage, and the nature of clouds

And by cropping the image carefully it can be made crystal clear that we really see fire gushing out of unit 2 ..
See attachment. Grin

 

[Bandit127]

And by cropping the image carefully it can be made crystal clear that we really see fire gushing out of unit 2 ..
See attachment. Grin

7:46 pm... It's crystal clear that it is a cloud lit by the sunset.

(Or did I miss subtle Physics humour there?)

EDIT - D'oh!

 

[MadderDoc]

<..> See for example attached graphs that shows proportion of key substances and their locations, including wet well, reactor building, and crucially 'environment'. Any takers for what location FHB stands for in this context?

I think it stands for Fuel Handling Building

 

[zapperzero]

There are a lots of new images and movies on Tepco's website today.

Broadly split into three categories, they cover new First Aid and medical check rooms at Daiichi and Daini, sampling of the 'ambient radioactive substances' at Unit 3 and some detail on the new cover for Unit 1.

The movies are large (>80MB) and zipped.

http://www.tepco.co.jp/en/news/110311/index-e.html"

High-res laser scan of the reactor 1 and environs. My, they have been busy.

EDIT: Can't open those .zip files. Can anyone who has luck with opening post them on rapidshare or something?

 

[~kujala~]

*Also,*my colleagues warn that the type of bed rock, which geologists identify,*and the strength/suitability of the*bed rock, which soil/geo-engineers determine, is different, ...

This is also something to note.
I am not sure if I understood it correctly but it might refer to a same thing as presented here:

http://iisee.kenken.go.jp/net/yokoi/bedrock/index.htm

In the viewpoint of Earthquake Engineering, it has been proposed, based on the followings, to use the shallower interface of which underlying stratum has from 300 to 700 m/sec of the shear wave velocity. This interface is called "Engineering Bedrock". ...
As the shear wave velocity of upper Earth crust is as homogeneous as from 3000 to 3500 m/sec, the upper interface of the upper Earth crust having 3000 m/sec of the shear wave velocity is called "Seismic Bedrock".

 

[Quim]

It may seem a silly question, but having looked at these data before, I never made it to decide whether "Wind direction" means the direction the wind is coming from, or the direction it is going?

Wind direction is stated as the direction the wind is coming from.

 

[triumph61]

High-res laser scan of the reactor 1 and environs. My, they have been busy.

EDIT: Can't open those .zip files. Can anyone who has luck with opening post them on rapidshare or something?

I have the same problem. CRC Mistake...

 

[Bandit127]

I have the same problem. CRC Mistake...

Let me know if this page works.
http://www.bandit127.com/Nuclear%20Stuff.htm"

If it does I will add the other videos to the page.

It takes a long time though - I have to download, link and then upload.

 

[SteveElbows]

The attached chart from page 2 of the report to IAEA attachment VI-1 shows estimated magnitude of releases over time. It certainly tells the story of how events at reactor 2 contributed to matters according to the analysis. And also a few interesting tales of slightly lower magnitude later on, what happened on March 30th for example?

I found the original source document from the NSC that this data came from, I don't think its available in english though. Much of the data is quite readable in english though. Using dodgy computer translation I can tell that it holds some useful information about the assumptions and data used to reach these conclusions, and some of the uncertainties, but I cannot trust this computer translation enough to talk in detail about this yet.

http://www.nsc.go.jp/anzen/shidai/genan2011/genan031/siryo4-2.pdf

 

[MiceAndMen]

Just to say I doubt of the "qualitative luminescence analysis", since I believe the cam is not in "fix exposition mode", but rather adapts automatically to the lighting conditions, as all webcam do. Except if you have evidence that this is not the case, or if you know very well how this automatic adjustment is done algorithmically, I do not think you can extract meaningful information from such an analysis.

The number of posts here regarding the non-events observed while glued to the Fukushima Webcam Entertainment Network is getting annoying.

 

[clif]

Let me know if this page works.
http://www.bandit127.com/Nuclear%20Stuff.htm

It worked for me on a computer running Ubuntu (linux).

 

[biffvernon]

I have here a chart that contains the general strengths of different rock types. It's in Finnish but I can give some translations. 'Siltstone' is 'lietekivi' and it belongs to a category 25 - 50 Mpa. 'Sandstone' is 'hiekkakivi' and it belongs to a category 50 - 100 Mpa. Of course these are only general guidelines. 'Granite' is 'graniitti' and it's > 250 Mpa.

The trouble with general terms like 'sandstone' and 'mudstone' is that they tell you approximately nothing about the strength and probably nothing about the permeability of the rock.

Sandstone is any sedimentary rock composed of sand grains; mudstone is a sedimentary rock made of much finer particles; siltstone is a sedimentary rock made of particles finer than sand but coarser than mud.

Sandstone may be very weak, crumbling in your hand, if the matrix that holds the sand grains together is weak. At the other extreme a metaquartzite is a rock made of grains of quartz sand cemented together by quartz that has crystallised in conditions of relatively high temperatures and pressures. It's harder and stronger than granite.

In the Fukushima case we seem to be dealing with something not so extreme. It is probably safe to assume that the sandstones and siltstones at the site are quite adequate to build power plants upon (the area of alluvium to the north and to the south has been avoided) and that for most practical purposes the siltstones can be regarded as impermeable to the flow of water while the sandstones will allow the passage of water albeit it at very slow rates. There is likely to be a net flow of water through the rock towards the sea, pressured by rainwater descending from the higher ground inland. Over a period of years one might expect contaminated water to move down and out and released to the Pacific Ocean.

There may be other pathways, joints and bedding planes, even cracks caused by earthquakes, that allow faster flow in complex directions but one needs more site-specific data to judge that.

 

[MiceAndMen]

High-res laser scan of the reactor 1 and environs. My, they have been busy.

EDIT: Can't open those .zip files. Can anyone who has luck with opening post them on rapidshare or something?

The zip files are corrupt according to winrar.

 

[LabratSR]

In WINRAR use the console and check the "Keep Broken Files" box.

 

[MadderDoc]

The zip files are corrupt according to winrar.

My Linux Archive mounter also gives errors during unpacking, although it does produce a reasonably playable wmv. However the resulting 'high resolution laser and whatnot' movie appears to me to be some not overly interesting computer generated graphics of some technical details of the unit 1 cover manipulation.

 

[Bandit127]

The zip files are corrupt according to winrar.

All 4 videos are now hosted on my site at:
http://www.bandit127.com/Nuclear%20Stuff.htm"

They are unzipped, original WMVs from TEPCO, so they will only work on some media players.

I consider this to be 'fair use' of TEPCO's copyright, since the files were hosted on a press release section of their website, but I will be happy remove them on request from TEPCO. http://www.jim-curtis.co.uk/Contact.htm"


EDIT - http://www.izarc.org/" unzipped them for me.

 

[MadderDoc]

Following this forum since a while, thanks to all. This is my first post, Hi everyone! :-)

Just to say I doubt of the "qualitative luminescence analysis", since I believe the cam is not in "fix exposition mode", but rather adapts automatically to the lighting conditions, as all webcam do. Except if you have evidence that this is not the case, or if you know very well how this automatic adjustment is done algorithmically, I do not think you can extract meaningful information from such an analysis.
For instance a cloud could now obscure the moon, the webcam would adjust with more gain and maybe show even more luminescence on average, while in reality it would not be true.

Jeremie

Hi Jeremy, and welcome. I think you are quite right in these observations.

 

[SteveElbows]

My Linux Archive mounter also gives errors during unpacking, although it does produce a reasonably playable wmv. However the resulting 'high resolution laser and whatnot' movie appears to me to be some not overly interesting computer generated graphics of some technical details of the unit 1 cover manipulation.

They got two descriptions the wrong way round. The laser video is really the last one, but its the most broken zip so we don't get to see many seconds of this video at the moment.

 

[MJRacer]

RE: Large emissions from Unit 2

Could it simply be that the emissions from Reactors 1 and 3 are being scrubbed by the torus in each unit and those of Unit 2 are no longer being scrubbed by its damaged torus?

 

[zapperzero]

All 4 videos are now hosted on my site at:
http://www.bandit127.com/Nuclear%20Stuff.htm"

They are unzipped, original WMVs from TEPCO, so they will only work on some media players.

I consider this to be 'fair use' of TEPCO's copyright, since the files were hosted on a press release section of their website, but I will be happy remove them on request from TEPCO. http://www.jim-curtis.co.uk/Contact.htm"


EDIT - http://www.izarc.org/" unzipped them for me.

Thanks a lot. Works a treat.

EDIT: Oh hell and tarnation. No it doesn't. The movies are broken. I'm beginning to suspect I need a system that uses two-byte characters, which I don't have available right now :P. I'll try to get one tomorrow, if no-one cracks it by then.

Anyway, again this stuff is ad usum Delphinii. God forbid they release the actual data. They made a scan and they're keeping it for themselves. We get happy-coloured animations and feelgood pictures of how hard they are working.

 

[clancy688]

EDIT - http://www.izarc.org/" unzipped them for me.

Thanks. So TEPCO does know that HD exists. Interesting. So we probably know now why all people had problems with the zip file. There's probably the last part of the zip missing.

The video number 4 (110614_16) is ~7 MB big, but has a length of 1:38. It stops at ~16 seconds, so there's a large chunk missing.

 

[Pu239]

People in Seattle got on average 5 hot particles per day for the month of April, 2011.
(acc. to Arnie Gundersen, Fairewinds Associates)
Question: What's the known effect of around 5 hot particles a day? The most I can find is the following, indicating a "big" risk of leukemias and cancer - from a study done in the 70s:

http://www.nuc.berkeley.edu/node/4459

Or, anyone with nuclear plant experience know anything about hot particles and what their effects might be?

Many thanks.

 

[Pu239]

People got around 10 particles each in Tokyo. The data is from air filters in Japan and the West Coast.

 

[Joe Neubarth]

People in Seattle got on average 5 hot particles per day for the month of April, 2011.
(acc. to Arnie Gundersen, Fairewinds Associates)
Question: What's the known effect of around 5 hot particles a day? The most I can find is the following, indicating a "big" risk of leukemias and cancer - from a study done in the 70s:

http://www.nuc.berkeley.edu/node/4459

Or, anyone with nuclear plant experience know anything about hot particles and what their effects might be?

Many thanks.

Any ionizing radiation exposure above normal is net additive to the potential for Cancer.