Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[clancy688]

Hm, another observation on Unit 3:

Image of March 14th, 3 minutes after the explosion:

http://www.digitalglobe.com/downloads/featured_images/japan_earthquaketsu_fukushima_daiichiov_march14_2011_dg.jpg

Image of March 16th:

http://www.digitalglobe.com/downloads/featured_images/japan_earthquaketsu_fukushima_daiichi3_march16_2011_dg.jpg

Note that on both pictures, which are two days apart, there are two different steam plumes originating in Unit 3.

Plume 1 = SFP, Plume 2 = RPV maybe?

 

[triumph61]

I found a Video at Stern.de 15. März 2011, 14:09 Uh.
B3 is dameged, B4 still ok.
http://www.stern.de/panorama/atomunfall-fukushima-explosion-reisst-loecher-in-reaktor-4-1663871.html

 

[Jorge Stolfi]

I've updated my plots of Fukushima Daiichi reactor variables, units #1--#3, up to NISA release 104 (20/apr 15:30) :

http://www.ic.unicamp.br/~stolfi/EXPORT/projects/fukushima/plots/cur/Main.html

The sudden factor-of-ten drop in the CAMS reading (A) of reactor #1 suppression chamber, which happened betwen NISA releases 97 and 98, is persisting. Perhaps all previous readings were wrong?

I am surprised at the large difference between readings for the CAMS od suppression chamber in reactor #2: the (A) reading is 0.55 Sv/h, the (B) reading is 103 Sv/h. (Yep, sievert, not millisievert.) How could that be?

 

[clancy688]

I found a Video at Stern.de 15. März 2011, 14:09 Uh.
B3 is dameged, B4 still ok.

Um... your video has been taken from the north west side, so you can't see the east side. Furthermore, the titel of the video is "Explosion reißt Löcher in Reaktor 4", translated "Explosion tears holes in reactor 4".
So it's NOT okay. ;)

 

[triumph61]

i don´t know when the video was taken. The original is NHK. There is no smoke at B3 seen.
B4 seems intakt at this side. Perhaps more than one explosion

 

[MadderDoc]

<..>regarding the report of a fire at Unit 4, check this on-line (copyrighted) document:

https://netfiles.uiuc.edu/mragheb/www/NPRE%20402%20ME%20405%20Nuclear%20Power%20Engineering/Fukushima%20Earthquake%20and%20Tsunami%20Station%20Blackout%20Accident.pdf

On page 6, seems to conclude that a fire has started "in the side of the Building 4" and has a different photograph of the smoke, less from Bldg 3 and more from Bldg 4.

It's the same photo, still from 11:04 JST. You can use the center smoke from unit 3 for 'fingerprinting'. It's all in how you cut and expose it. What your eye interprets as 'more smoke' from unit 4, is just the light of the sun reflected by the roof of the unit 4 turbine building.

Reflected why? Because the roof is still _wet_ from the fallout of the grand expulsion of steam and water from unit 3 that happened a few minutes earlier.

I still can't separate what smoke is definitely coming from the exhaust tower vs what might be coming from the east side of Bldg 4.
Photo excerpt attached. It would be useful to have the original photo. Resolution is poor and the light is tricky.

Indeed it is :-)

 

[jmelson]

clancy 688: that may be A difference (I have to confirm your elevation data) but still, the picture i posted shows that there has also been a heavy flooding of the platform at the Daini plant (which i didn't really know about to tell you the truth). At the Daichi plant, if i remember well, the diesel generators were at ground level (or even below ground level maybe, in the basement of the turbine building? Don't remember...). So my point is: ok the tsunami has been worse at Daichi than at daini because some difference of height of the platform but still, did the EDG at Daini went under water, or close to go under water too?

http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110409e9.pdf

Daini maintained grid power, so the Diesel generators were not critical to maintaining cooling.
I think THAT may have been the main difference. The extra elevation sure didn't hurt, though.

Jon

 

[triumph61]

one more Video
http://www.stern.de/panorama/atomkatastrophe-in-japan-erneute-explosion-setzt-radioaktivitaet-frei-1663662.html

 

[clancy688]

http://www.stern.de/panorama/atomkat...i-1663662.html

If you're referring to the helicopter flight video around the plant - that was probably taken before the accident. All Units are fine and there's no tsunami damage whatsoever at the other buildings.

-------------------------------------------------------------------------------

Robot videos online: http://www.tepco.co.jp/en/news/110311/index-e.html

 

[jmelson]

Not-so-fun-fact:

http://english.kyodonews.jp/news/2011/04/82888.html

Maximum run-up height was 37.9 metres in Taro. The village was featured in an 2005 Discovery Channel documentary about Tsunamis. They talked about their 10 metre tsunami wall and how this wall is offering them only partial protection.
Watching that documentary now is like watching a prophecy... Taro's been totally shattered by the March 11th monster wave.

Holy cow, that's 124 FEET!

Jon

 

[AntonL]

...

What is the meaning of the "O.P." acronym ?

Observation Post a fixed reference level set in concrete before work begins.

 

[MadderDoc]

Hm, another observation on Unit 3:

Image of March 14th, 3 minutes after the explosion:

http://www.digitalglobe.com/downloads/featured_images/japan_earthquaketsu_fukushima_daiichiov_march14_2011_dg.jpg

Image of March 16th:

http://www.digitalglobe.com/downloads/featured_images/japan_earthquaketsu_fukushima_daiichi3_march16_2011_dg.jpg

Note that on both pictures, which are two days apart, there are two different steam plumes originating in Unit 3.

Plume 1 = SFP, Plume 2 = RPV maybe?

In most photos there appears to be two distinct sources of steam/smoke from unit3. The northern of those plumes seems to originate from the area of the chute between the reactor and the utility pool. The southern plume from the opposite side of the reactor area, close to the chute to the SFP. I don't remember any photos in which steam unambiguously was seen coming from the SFP itself, rather than the chute. Between the two apparent sources lies the booms of the heavy overhead crane and the crane itself, sunk into the concrete reactor lid and the service deck

 

[triumph61]

If you're referring to the helicopter flight video around the plant - that was probably taken before the accident. All Units are fine and there's no tsunami damage whatsoever at the other buildings.

-------------------------------------------------------------------------------

Robot videos online: http://www.tepco.co.jp/en/news/110311/index-e.html

No! Look at 1.36 at the Video. Left B1 (damaged) B2, B3 damaged, B4 still seems ok.

 

[Rive]

Yes, the dark spots are draped debris, probably roofing insulation, and presumably from the explosion at Unit 3, not from an explosion at Unit 4.

It's possible that one of the dark spots are predate the explosion of U3 - check the video in #4433 at 01:19.

Do we have any earlier high resolution picture about this area?

 

[clancy688]

No! Look at 1.36 at the Video. Left B1 (damaged) B2, B3 damaged, B4 still seems ok.

Nope. You can't say that for certain. We can only see the north and west walls of the building, not the south and east ones.
Destruction at Unit 4 startet with two panels which were blown out. But I don't know on which side of the building.

 

[tsutsuji]

Observation Post a fixed reference level set in concrete before work begins.

I have tried to google it again and found the following, seemingly meaning some sort of altitude reference used in Japan :

O.P. (Osaka Peil) means the lowest low-water level observed in Osaka Port in 1885 and this level is used as the standard datum in Osaka area

page 185 of http://wwwrcamnl.wr.usgs.gov/rgws/Unesco/PDF-Chapters/Chapter9-5.pdf

See http://en.wikipedia.org/wiki/Datum_(geodesy)

Other datums used in Japan are the "Tokyo Peil" (T.P.), "Arakawa Peil" (A.P.), "Yodogawa Peil" (Y.P.) : http://www.dobokunet.com/modules/xwords/search.php?term=peil

► At Fukushima Daiichi, countermeasures for tsunamis had been established with a design basis height of 5.7 m above the lowest Osaka Bay water level.

page 16 of http://www.vgb.org/vgbmultimedia/News/Fukushimav15VGB.pdf

Peil is borrowed from Dutch :

2.peil noun
♦level
♦plane
♦standard
http://www.systranet.com/dictionary/dutch-english/peil

 

[triumph61]

Nope. You can't say that for certain. We can only see the north and west walls of the building, not the south and east ones.
Destruction at Unit 4 startet with two panels which were blown out. But I don't know on which side of the building.



And that's, as mentioned before, archive material from BEFORE the tsunami.

When the south and east Side is blown away, you think so, then there was more as one Explosion.

 

[MadderDoc]

Also remember that the SkyGlobe pic is taken from orbit, so it will include any clouds that happened to be between the plant and the satellite, even in the statosphere. Not so for wbcam and airplane pics.

That is generally true, however at the time of this particular photo, shortly after the unit 3 explosion, no clouds got into the picture. On the zoomout you see that clearly:

 

[clancy688]

When the south and east Side is blown away, you think so, then there was more as one Explosion.

Hm... I was confused by the report of two holes in the side of the reactor:

Japan's nuclear safety agency NISA reported two holes, each 8 meters square, or 64 square metres (690 sq ft), in a wall of the outer building of unit 4 after the explosion.

http://www.reuters.com/article/2011/03/15/japan-nuclear-holes-idUSTFD00668920110315But I have taken a look at the webcam pictures from the NPP-Webcam. There you can clearly see, that ALL of the damage occurred on March 15th between 6:00 and 7:00 am JST (because the roof is blown off then).
So every video shot at March 15th or later should show a destroyed Unit 4 building. If not, it's from March 14th or earlier.



You can also see that there are very bad weather conditions on that day. Since there's been a no fly zone 20 or 30 km around the plant, every video was shot from 20 or 30 km away. With such weather conditions, that would be impossible. That's why we don't have videos or sat images from March 15th.

 

[Jorge Stolfi]

I am truing to build a computer graphics model of the Fukushima reactors #1--#4. Does anyone know where I can get dimensional data? Even the basic data would help:

* outside width,length,height of the top part building
* ditto for the lower part
* diameter of RPV and drywell
* depth of basement below road level

Those would be enough to get started, as I can deduce other rough measurements from other cutaway drawings, photos, and models.

Thanks...

 

[clancy688]

Those would be enough to get started, as I can deduce other rough measurements from other cutaway drawings, photos, and models.

Don't know if that helps you, but here are Blueprints of Unit 1:

http://www.houseoffoust.com/fukushima/blueprint.html

 

[|Fred]

some nice 3d modeling has already been done ;) but they are not entirely accurate


Outside (fukushima)

http://sketchup.google.com/3dwarehouse/details?mid=f04823398eed697d3fdfd6bc6322f73b&hl=fr&ct=lc

http://sketchup.google.com/3dwarehouse/details?mid=11b70c1651c0b152f0725315050aa28f&prevstart=12


Inside (not fukushima)
http://sketchup.google.com/3dwarehouse/details?mid=9d08f6a2a38642b0ef378390a82b2ba&prevstart=24

 

[MadderDoc]

<..>
But I have taken a look at the webcam pictures from the NPP-Webcam. There you can clearly see, that ALL of the damage occurred on March 15th between 6:00 and 7:00 am JST (because the roof is blown off then).
So every video shot at March 15th or later should show a destroyed Unit 4 building. If not, it's from March 14th or earlier.



You can also see that there are very bad weather conditions on that day. Since there's been a no fly zone 20 or 30 km around the plant, every video was shot from 20 or 30 km away. With such weather conditions, that would be impossible. That's why we don't have videos or sat images from March 15th.

Indeed there is a dearth of images from that day. This is the only photo I think likely was taken on March 15th. (I think that because inland smoke plus overcast appears to have ben a rare combination on the 16th)
[URL]http://www.tepco.co.jp/en/news/110311/images/110316_1f_chijou_2.jpg[/URL]

However I am sure there must be other photos, clearly there were choppers in the air, see the webcam 7 am on March 15th:

[PLAIN]http://pointscope01.jp/data/f1np/f1np1/pic/20110315070000.jpg

 

[triumph61]

Unit 3(Shut down)
-Explosive sound and white smoke were confirmed at approximately 11:01am
on March 14th. It was assumed to be hydrogen explosion.
-From 6:02 pm on March 25th, we started injecting fresh water to the
reactor and are now injecting fresh water by a motor driven pump powered
by the off-site transmission line.

Unit 4(outage due to regular inspection)
-At approximately 6:00 am on March 15th, we confirmed the explosive sound
and the sustained damage around the 5th floor rooftop area of the Nuclear
Reactor Building.

Therefore the Video was taken between 14.3. 11.01am till end of day ~7.00pm.

 

[clancy688]

Don't know if that's been recognized before - Seawater contamination levels are clearly falling. TEPCO's advances to stop water leakage into the ocean are apparently successfull:

http://fukushima.grs.de/sites/default/files/Daten_Seewasser_I131_20110420-0800.pdf
http://fukushima.grs.de/sites/default/files/Daten%20Seewasser_Cs137_20110420-0800.pdf

And I didn't realize it until now, but since three weeks, there has been no new airborne contamination!

http://fukushima.grs.de/sites/default/files/Messwerte%20ODL%20Fukushima%20Daiichi_110420-1230_Gesamt.pdf

So I guess the reactors are somehow stable / not open to the environment...?

 

[htf]

@default.user There are German forums

Das ist fraglich.
...
Wie lange war die Kühlung in Daiichi unterbrochen?

@default.user Jag es durch den google-Übersetzer - der haut ganz gut hin.

But now in English.

There are German forums where you can ask your questions in your mother tongue. This forum is quite nice (but it is a much smaller community than physicsforum.com):
http://fukushima.physikblog.eu/discussions
They have a summary of the current status of Fukushima plant and the course of the events of the accident.

And there is the dedicated page of the GRS (Gesellschaft für Anlagen- und Reaktorsicherheit). They are payed by our taxes to collect, summarize and evaluate information regarding Fukushima accident:
http://fukushima.grs.de/
They may not have thrilling news like Arnie Gunnarson but what they say is reliable information.

BTW - google translator does a good job. So my English seems to be not too bad ...

 

[jlduh]

Jon

Daini maintained grid power, so the Diesel generators were not critical to maintaining cooling.
I think THAT may have been the main difference

well, your are right, that may be the main difference in fact. In this case, that would be more a big LUCK, considering the flooding of the plant...

 

[jlduh]

When i consider the layout of the Daichi plant, and especially the transversal cut of the buildings, it is clear that the reactor building and the turbine building go deep in the ground of the platform, so the basement of these buildings (for example where the torus sits) is i think something like almost 10 meters below the ground (more data on this would be needed though). Considering that the platform is around 10 meters abose sea level, it is clear that there is not much margin between the basements of the buildings and the sea level.

This leads me to consider that one of the reason (and maybe the main reason at the time of the design??) for the plaform was also to put the basement of these rooms a little bit above what we can imagine being the phreatic level, so the concrete doesn't lay in undergroud water.

It is reasonable to consider that the phreatic level of underground water is more or less the sea level, based upon the proximity of the ocean. This leads me to the subject of the contamination of the the phreatic water by contaminated water: it is said (but with very few data until now, if you have some please post!) that phreatic water is now heavily contaminated, but i didn't sea any map of the underground phreatic water in this area (deepness, size and direction of flows, and of course possible impacts on various uses of this resource).

Did somebody found some useful data on this subject?

 

[Joe Neubarth]

Don't know if that's been recognized before - Seawater contamination levels are clearly falling. TEPCO's advances to stop water leakage into the ocean are apparently successfull:

http://fukushima.grs.de/sites/default/files/Daten_Seewasser_I131_20110420-0800.pdf
http://fukushima.grs.de/sites/default/files/Daten%20Seewasser_Cs137_20110420-0800.pdf

And I didn't realize it until now, but since three weeks, there has been no new airborne contamination!

http://fukushima.grs.de/sites/default/files/Messwerte%20ODL%20Fukushima%20Daiichi_110420-1230_Gesamt.pdf

So I guess the reactors are somehow stable / not open to the environment...?

What we know from the data as presented.
After the explosions the contamination on the ground is decaying and not spreading.
The flow into the sea is greatly decreased.
Radiation released to the atmosphere is not known with any accuracy.

 

[Dmytry]

Jon



well, your are right, that may be the main difference in fact. In this case, that would be more a big LUCK, considering the flooding of the plant...

dont forget electrical equipment was also in basement in daiichi, not only the generators.

 

[MiceAndMen]

Don't know if that helps you, but here are Blueprints of Unit 1:

http://www.houseoffoust.com/fukushima/blueprint.html

You will notice a lot of references to "OP" on that drawing. I interpret OP as roughly "above sea level". There are also elevation numbers abbreviated with "EL". They seem consistent. Notice the level of the ground is listed as "OP. 10000", i.e. 10 meters above sea level.

 

[MiceAndMen]

That's probably not the case. The recently announced TEPCO-6-month-plan stated, that they'll fill the containments of Units 1 and 3 with water in the near future, indicating that they're currently dry and unfilled.

It also assumes the containments are able to hold water without leaking. Are they even in a position to determine that yet with any certainty?

To me, it seems as though their announced plans/roadmap are all a bit premature and designed to give the appearance that they know what they're doing lest anyone challenge their competence further.

 

[PietKuip]

And I didn't realize it until now, but since three weeks, there has been no new airborne contamination!

http://fukushima.grs.de/sites/default/files/Messwerte%20ODL%20Fukushima%20Daiichi_110420-1230_Gesamt.pdf

That is not quite true. When winds are inland, there is fallout in Ibaraki and as far away as Tokyo; see pages 4 and 5 of http://www.slideshare.net/iaea/radiological-monitoring-and-consequences-19-april-2011

 

[clancy688]

That is not quite true. When winds are inland, there is fallout in Ibaraki and as far away as Tokyo; see pages 4 and 5 of http://www.slideshare.net/iaea/radiological-monitoring-and-consequences-19-april-2011

Okay, let's change it towards "no airborne contamination which's strongly changing the radiation levels". ^^

 

[jlduh]

Does somebody understand this strange statement:

"The company says water levels are also rising in the Number 5 and 6 turbine buildings."

http://www3.nhk.or.jp/daily/english/21_03.html

Why would the water level rise in these buildings?