Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[Jorge Stolfi]

It certainly does. The photo must have been taken after the tsunami, and before the debris on the road by that orange crane was cleared. From the direction of sunlight, the time of day would appear to be in the morning, about 8 am. The clearness of the sunlight is inconsistent with the weather conditions in the morning of March 13th. This really leaves us with no other choice than to accept the date to which it is attributed, March 12th.

Thanks. But then, if the two pictures were taken on the same flight, the Green Box is obviously not a shadow of the tower's top (which can be seen on the second photo, further to the south and much larger). And if they were taken at ~08:00 on the 12th, then the Green Box survived the tsunami.

The Green Box in those pictures looks reasonably similar to the Greenish Closet of the latter pictures.

Looks like some scaffold. ... Maybe it was covered with something green like this :http://image.ec21.com/image/greennet/simg_GC03913493_CA03915980/PE_Nets_Scaffolding_Cover_Net_Debris_Net_Shade_Net.jpg

Indeed, the other pictures (by the drone looking down, and of workers from the ground) are consistent with that too: a metal strucure covered by a loose plastic net.

Maybe for some repairs on the outer wall. Such scaffold could disappear easily.

Perhaps, but It looks a bit too "dense" and sturdy for a simple maintenance scaffold. A support for temporary pipes or equipment, perhaps?

 

[rowmag]

03:50 pm February 10th : A leak in reactor 4 , 2 liters of contaminated water was found during periodic inspection ...

If you look through the reports from the past few years, there is always some little leak being discovered and fixed somewhere. I don't think it means anything very interesting for the present situation, though. Just routine maintenance stuff, seems like.

One confounding factor for the isotope concentration and ratio analyses is that there appears to be some coupling between underground water accumulations from different reactors. It has been observed, for example, that the turbine hall basement water levels for Units 3 and 4 seem to be rising and falling together, so there is some suspected leakage path between the two. The sub-drain sampling points are even further away from the reactors than the turbine hall. So, I think it is going to be difficult to diagnose leaks in SFP4, for example, from measurements made in the sub-drains.

 

[Cainnech]

This really leaves us with no other choice than to accept the date to which it is attributed, March 12th.

Yes, I'm quite sure you are right there. I tried to track the photo at gettyimages.com. Unfortunately the information has been removed (at least where I looked), but the current google cache of the image information says that the photo was taken at march 12th:
http://webcache.googleusercontent.com/search?q=cache:VTi8HUvLZ84J:www.gettyimages.com/detail/110022112+site:gettyimages.com+fukushima+nuclear&cd=14&hl=sv&ct=clnk&gl=se&source=www.google.se

Caption: An aerial view shows the quake-damaged Fukushima nuclear power plant in the Japanese town of Futaba, Fukushima prefecture on March 12, 2011. Japan scrambled to prevent nuclear accidents at two atomic plants where reactor cooling systems failed after a massive earthquake, as it evacuated tens of thousands of residents. Tokyo Electric Power, which runs the plants, said it had released some radioactive vapour into the atmosphere at one plant to relieve building reactor pressure, but said the move posed no health risks. AFP PHOTO / JIJI PRESS (Photo credit should read STR/AFP/Getty Images)
Date created: 12 Mar 2011 , Photographer: AFP/Stringer, Object name: Hkg4680477.

 

[MadderDoc]

Having stared at a few captures of this video for a while,I think people should be very careful when looking for damage to the racks themselves.

If I look carefully at the racks, then it seems that there are lugs/handles which protrude higher than the rest of the rack. They can be seen most clearly on the rack that is to the right of the image, and once noticed are also easy to spot for the rack we have a full view of in the middle. As they seem to always be on the third row of fuel slots from the edge, they would also be present in just the area you have pointed to with arrows, and if not taken account of may look like distortion to the racking.

Attached is an image with pairs of these circled.

Right, so we better steer clear of those handles:
[URL]http://gyldengrisgaard.dk/fuku_docs/sfp4_rackdamage2.bmp[/URL]

 

[MiceAndMen]

PDF with the core shroud replacement schedule for unit 4. Interesting pic on page 1 shows the core shroud being hoisted out of the cavity.

http://www.tepco.co.jp/nu/f1-np/state/unit4/data/1f4shroud.pdf

I think the apparent hole in those Unit 4 pics is related to the core shroud replacement project. The bright green appearance on the photo from September 2010 may be a tarp covering the construction of the hole/door/hatch. Replacing the reactor core shroud probably wasn't planned for when the building was designed, and maybe they needed another access passage to get the old shroud out and the new one in. The SE corner at that level just might have been the most convenient location.

I still wish we had an engineering drawing of the refueling floor plan. Normally one does not move heavy objects over the SFP using the bridge crane. It would be interesting to see how much clearance there was between the east wall of the SFP and the east wall of the RB.

 

[razzz]

@Jorge Stolfi

Great work on the renderings!

At your post:
https://www.physicsforums.com/showpost.php?p=3275086&postcount=5393
You say/ask:
"However, the flanges connecting shroud and drywell seem to be rather massive things held together with a zillion heavy bolts. So I would expect that the walls of the drywell will rupture at some weld somewhere else, well before the bolts do. Is that correct?"

See page 5 of 7 in attached DOE-leakage study.pdf where it says;

"For the BWR Mark I -- a leak area of 35 sq in was estimated at -- 117 psig --. Most of this leak area (approximately 95%) is attributed to the drywell head which is predicted to unseat at a pressure of 27 psig."

The study described in the attached pdf "concentrated on identifying potential leakage paths that may occur prior to reaching currently reported containment shell capability pressures."

In other words, at a containment pressure [117 psig] which is much less than the design strength of the steel containment, the drywell head will unseat and leak.

@razzz

Is the above DOE-leakage study.pdf the report you remembered?

.

That was a nice find and close enough to backup the discussion. I still can't find the paper I was reading, I think it was at .docstoc but the history links I have timeout when I click on them (never load) so I can't check. I could have swore it was an independent study with a mock up with real time pressure heating until failure. Oh well, seals failing after achieving rated temperatures during certain time frames is not surprising just renders containment as worthless in the extremes.

The smaller Unit 1 might still be holding pressures if what the gauges report are to be believed probably because a slightly over-design was adhered to on the first attempt.

 

[dh87]

As others have observed, we can see when the camera enters the water (at frames 35-40) and comes out again (150-155).

It is not the illumination that is waving, the rack shapes get visibly distorted and magnified. And I do not think it is salinity either; the flakes show vigorous convenction, so the salt and fresh waters must be well-mixed by now.



Yes. Could they be steam? If the pool water near the surface is at 90 C, wouldn't steam bubbles condense before rising more than a few feet?

If they are not steam, what could it be? Too many and too late for disolved air. Hydrogen? Presumably, if the flow of water through an assembly is suffciently blocked at some point, a steam bubble will form below the block, and then fuel in that region can get arbitrarily hot.



Indeed. In your sharper picture the light curved spots in row 2 (lower) resolve into a row of handles like those in row 7, and separate round spots belonging to the top of the assemblies.

Can the bubbles that people have noticed be caused by radiolysis of water, which releases H₂, O₂, and O₃?

 

[MadderDoc]

<..>if they were taken at ~08:00 on the 12th, then the Green Box survived the tsunami.

Mm. In this 'before and after' image we see, to the left, the green box hanging on the wall in late 2010 -- and to the right, the same wall, photographed the day after the tsunami.

 

[MadderDoc]

Can the bubbles that people have noticed be caused by radiolysis of water, which releases H₂, O₂, and O₃?

I suppose it could. Hydrogen could also come from the chemical reaction of aluminium with hot water, as promoted by salt. I understand all three ingredients are present in the soup.

from:
http://www.eere.energy.gov/hydrogenandfuelcells/pdfs/aluminium_water_hydrogen.pdf

 

[georgiworld]

Interesting video showing external situation around the reactors.


Pity it's in Japanese. Why is the US media silent?

It seems there is a sheet covering something in the video in which someone on another forum believes is a fuel assembly and RPV cap.

http://files.abovetopsecret.com/images/member/bb837fdce30f.jpg

Any ideas?

 

[MadderDoc]

<..>
I think the apparent hole in those Unit 4 pics is related to the core shroud replacement project. The bright green appearance on the photo from September 2010 may be a tarp covering the construction of the hole/door/hatch. Replacing the reactor core shroud probably wasn't planned for when the building was designed, and maybe they needed another access passage to get the old shroud out and the new one in. The SE corner at that level just might have been the most convenient location.

I put the new shroud on the roof, ready for you to bring in through the hatch.

 

[Jorge Stolfi]

Mm. In this 'before and after' image we see, to the left, the green box hanging on the wall in late 2010 -- and to the right, the same wall, photographed the day after the tsunami.

Well, the mystery thickens. The sequence seems to be

* AERIAL IMAGE A: Late 2010: A neat Light Green Box is on the terrace. Staircase on south wall.

* March 11, 2011: earthquake + tsunami.

* AERIAL IMAGES B1,B2: March 12, ~8:00: Green Box apparently lost the light green skin, became the Big Greenish Closet - actually an open metal framework, still on terrace. Staircase situation unknown.

* March 14, 11:00: explosion of #3

* AERIAL IMAGE C: Unknown time: Big Closet gone, Thing with Mickey Mouse Ears in its place. Big Closet may be hanging from terrace by two bundles of pipes/cables. Upper part of staircase still on south wall.

* March 15, 06:00: explosion of #4

* DRONE IMAGE D, GROUND IMAGE E, after #4 explosion: Thing with Mickey Mouse Ears destroyed or buried by debris. Greenish Closet definitely hanging from terrace. Staircase gone.

What was the date of the photo showin the Mickey Mouse ears?

I think the apparent hole in those Unit 4 pics is related to the core shroud replacement project.

Not likely. According to the blueprints we have, that floor (3rd) seems quite cramped. Behind the wall, at that spot, there is only a relatively small space (less than 6 m wide and 5 m high) around the base of the spent-fuel pool. Any reactor parts would have to be lowered from the 5th floor (where the reactor opening is) to the 3rd floor through the elevator shaft --- whch is on the West side of the building, and goes straight down to the entrance door on the ground floor.

From its location, it seems possible that the Green Box had something to do with the spent-fuel pool. However there must be also a lot of machinery on that floor that is not related to the SFP.

 

[MiceAndMen]

I put the new shroud on the roof, ready for you to bring in through the hatch.

Nice try. According to this http://www.irpa.net/irpa10/cdrom/00584.pdf the core shroud is approximately 4.5 meters in diameter and about 7 meters high. So it would more closely resemble the attached pictures.

It's almost a perfect fit.

The amount of room to work between the wall and the SFP could be a problem for this arrangement. That is certainly true. Thus, my thirst for more and better blueprints. I was frankly surprised when I quickly whipped up the core shroud cylinder and placed it on the low roof. There could be other reasons why they needed a 5 x 5 m opening (or whatever it is).

 

[jim hardy]

Pity it's in Japanese. Why is the US media silent?

It seems there is a sheet covering something in the video in which someone on another forum believes is a fuel assembly and RPV cap.

http://files.abovetopsecret.com/images/member/bb837fdce30f.jpg

Any ideas?

i think that thing behind sheet must be an array of instrument tubes. it looks like there are little clamps over them and the horizontal supports are spaced closer than on the fuel element in inset.

were that a spent fuel element, getting that close to it should kill any CMOS IC's in the camera.

why media silent?
I think TPTB had planned on nuclear renaissance fueling our economy for next decade replacing our antique nuclear power plant fleet.
watch for applied mass psy-ops.

 

[elektrownik]

It seems there is a sheet covering something in the video in which someone on another forum believes is a fuel assembly and RPV cap.

http://files.abovetopsecret.com/images/member/bb837fdce30f.jpg

Any ideas?

No way it would be extream radioactive, and it would melt without cooling.
About unit #4. This is possible that they were repleacting core shroud, reactor 4 was shout down and defueled becouse there was some crack in core shroud, so this would be possible that they were repleacing it. There is no much space, but look on this photo:

 

[htf]

Japans government advisor Kosako for nuclear energy resigns

Has anybody noticed this?

http://www.spiegel.de/wissenschaft/mensch/0,1518,759906,00.html

A brief summary of this article in English:

Prof. Kosako, recently announced advisor of the Japanese government on nuclear energy, has resigned and accuses the Japanese government of breaking the laws. He is frustrated and said with tears in his eyes that he cannot accept the government's decision to increase the safe dose for children to 20 Millisievert per year, which is the maximum permissible dose for a German NPP worker. He also says that he got the impression that the government is not seeking for a real solution for the crisis but is playing for time with interim and emergency solutions. The article states that it is very exceptional for a scientist to resigns under protest from such a prestigious job

I know that this is a thread about the technical aspects of the Fukushima crisis. But it is nevertheless important to notice what insiders think about the crisis management of the Japanese. People like Gunderson and Busby may not be 100% reliable but they seem to bring up painful subjects.

 

[MiceAndMen]

About unit #4. This is possible that they were repleacting core shroud, reactor 4 was shout down and defueled becouse there was some crack in core shroud, so this would be possible that they were repleacing it. There is no much space, but look on this photo:

There is no doubt they were replacing the core shroud. TEPCO claims it was for preventive maintenance, not because of any cracks. As for that photo, I'm not sure what it shows. The caption says something about existing piping, but Google translations are not always clear. I don't think it's a core shroud.

 

[~kujala~]

I noticed yesterday there was this spike in the sub-drain radiation of the unit 4 on the 20th of April.

Now when examining more closely the sub-drain data the same kind of spike can be seen in the unit 1, 3 and 6.

In this picture I put the data from 1, 3, 4 and 6 on top of each other so that this spike can be more clearly seen:
http://varasto.kerrostalo.huone.net/sub_drain_spike.png

I think what one can see in the sub-drain data is the mixture from airborne radiation passing through the ground into the groundwater (this takes some time) and leaks from the reactors (takes some time also).

In the case of 5 and 6 the most of it might be coming from airborne radiation.

The spike on the 20th of April might be the result of an airborne spike in March which has taken a long time to be seen in the groundwater.

If groundwater from 1 - 6 is mixing with each other it is even more complicated.

Source:
http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110430e12.pdf

 

[zapperzero]

Interesting video showing external situation around the reactors.

Same video as posted by me a couple pages back.

That being said, some effort to collate all the released media files and stick them on a timeline would surely be a lot of help for armchair analysts like us. Is there such a project? If not, maybe we could set it up ourselves?

 

[zapperzero]

(2) change the concentration of 9 × fuel gadolinia 9 (B type) * 1 × 9 fuel the adoption of the traditional 9 (B type), as well as reduce the concentration of a substance Gadolinia reaction to the early to mid-fuels plant operation High fuel 9 × 9 (B type)
And then the body uses 96.

9 or more * Change Fuel concentration 1 × gadolinia 9 (B type)
Gadolinium (Gd) oxide compounds gadolinia (Gd2O3) concentration of
Uranium fuel currently being used (concentration gadolinia: about 3.0 to about 5.0wt%) have higher fuel (gadolinia concentration: about 5.0 to about 7.0wt%).
Gadolinia high neutron absorption capacity, but using a fuel containing uranium Gadolinia traditionally used by the high concentration of uranium Gadolinia, the degree of combustion reaction in the reactor plant operation has the effect easier to control than the control.

Wait, what?Are they talking about changing some of the fuel? To one with a higher gadolinia (gadolinium oxide) content? Where's a nuclear engineer when you need one? Or a Japanese translator?

Areva reprocesses fuel and http://www.areva.com/EN/operations-996/fbfc-dessel-fabrication-of-fuel-assemblies-for-pwrs.html" sintered gadolinium oxide-uranium oxide fuel pellets. Are they involved in the cleanup because they were involved in the fueling?

 

[Uagrepus]

Mm. In this 'before and after' image we see, to the left, the green box hanging on the wall in late 2010 -- and to the right, the same wall, photographed the day after the tsunami.

What looks like "Mickey-Mouse-Ears" under some conditions could be the upper ends of the scaffold, especially when these are covered by a net. Also possible, something is standing on top of the second scaffold-floor ... Osama?

 

[elektrownik]

From new nisa report we can see that all temperatures are going up...

 

[triumph61]

Wait, what?Are they talking about changing some of the fuel? To one with a higher gadolinia (gadolinium oxide) content? Where's a nuclear engineer when you need one? Or a Japanese translator?

Areva reprocesses fuel and http://www.areva.com/EN/operations-996/fbfc-dessel-fabrication-of-fuel-assemblies-for-pwrs.html" sintered gadolinium oxide-uranium oxide fuel pellets. Are they involved in the cleanup because they were involved in the fueling?

My Post was delete.
Here is the Link
http://translate.googleusercontent.com/translate_c?hl=en&sl=auto&tl=en&u=http://www.tepco.co.jp/cc/press/10112901-j.html&rurl=translate.google.com&twu=1&usg=ALkJrhh5cZUC-12CYSJAwPXPDYkknQed_w

Original:
http://www.tepco.co.jp/nu/f1-np/state/unit4/u4_2010-j.html 11.29

 

[fluutekies]

Wait, what?Are they talking about changing some of the fuel? To one with a higher gadolinia (gadolinium oxide) content? Where's a nuclear engineer when you need one? Or a Japanese translator?

I'm not a nuclear engineer, but a process chemist, but AFAIK the fuel rods are not filled homogeneous with the same pellets. In order to control neutron flux and density in the core, pellets with e.g. Gd (neutron absorber) are placed in certain positions. Even the rods are not equal distributed in the core. The intention is to get a uniform heat distribution over the core. This seems to be a kind of "science" on it's own. Read it about some time ago, but can't find the source now.

 

[Cainnech]

What looks like "Mickey-Mouse-Ears" under some conditions could be the upper ends of the scaffold, especially when these are covered by a net. Also possible, something is standing on top of the second scaffold-floor ... Osama?

Another copy of the photo of the "shadow" with a slightly better resolution.
http://www.abc.net.au/reslib/201103/r733167_5929130.jpg
Found it here: http://www.abc.net.au/news/photos/2011/03/12/3162376.htm

I have no idea what it is, but to me it looks like some sort of rack or grid with kind of a tube on top...

 

[rowmag]

Wait, what?Are they talking about changing some of the fuel? To one with a higher gadolinia (gadolinium oxide) content? Where's a nuclear engineer when you need one? Or a Japanese translator?

I'm neither a nuclear engineer nor a professional translator, but it says that in addition to the original 9x9 B-type fuel assemblies, it is adding 96 assemblies (also 9x9 B-type) which contain a higher proportion of gadolinia.
The original uranium fuel has a concentration of about 3-5% by weight of gadolinia, and the new fuel will have 5-7%.
The gadolinia acts as a neutron absorber, and will improve the ability to control reactions within the reactor.

Source:
http://www.tepco.co.jp/cc/press/10112901-j.html

Sounds like it might have something to do with what fluutekies is talking about.

 

[default.user]

http://youtu.be/kO0flpwmjJI

Can anyone translate this videos?

More on 77-year-old Michio Ishikawa of the Japan Nuclear Technology Institute on the situation at Fukushima I Nuke Plant, as he appeared on Asahi TV on April 29. [...]

“I believe the fuel rods are completely melted. They may already have escaped the pressure vessel. Yes, they say 55% or 30%, but I believe they are all melted down. When the fuel rods melt, they melt from the middle part on down.

“I think the temperature inside the melted core is 2000 degrees to 2000 and several hundred degrees Celsius. A crust has formed on the surface where the water hits. Decay heat is 2000 to 3000 kilowatts, and through the cracks on the crust the radioactive materials (mostly noble gas and iodine) are escaping into the air. [...]

[Later on] The show’s host says “But wait a minute, Mr. Ishikawa, you are a proponent of nuclear power and we expected to hear from you that everything is going well at Fukushima…”

Mr. Ishikawa answers, “Well, if I’m allowed to tell a lie…”

 

[zapperzero]

I'm neither a nuclear engineer nor a professional translator, but it says that in addition to the original 9x9 B-type fuel assemblies, it is adding 96 assemblies (also 9x9 B-type) which contain a higher proportion of gadolinia.

Can't be. The number of channels in the core where bundles (assemblies) go is fixed, no?

 

[~kujala~]

Also these might have caused the http://varasto.kerrostalo.huone.net/sub_drain_spike.png" on the 20th of April in units 1, 3, 4 and 6:

Unit 2:
April 19th 10:08~ Started to transfer the stagnant water with high-level radioactivity from the trench of the turbine building to the buildings of radioactive waste treatment facilities.

Unit 6:
April 19th 11:00~15:00 Transferred stagnant water under
the base of the turbine building to the condenser for
measuring the amount of it.

http://www.nisa.meti.go.jp/english/files/en20110430-3-2.pdf

As for the route from unit 2 to the waste treatment facility...

From these pictures one can see that the route from unit 2 trench to the facility goes through/near 2, 3 and 4 turbine buildings:
http://varasto.kerrostalo.huone.net/pump_route.jpg
http://varasto.kerrostalo.huone.net/pump_route_2.jpg

Here is the text related to these pictures:
http://www.ordons.com/asia/far-east/24807-tepco-to-accelerate-transfer-of-radioactive-water.html

So if the hoses are leaking you never know where the water is going to end.

About the radiation in the number 6 building:

The operator of the troubled Fukushima Daiichi nuclear power plant plans to begin transferring highly radioactive water accumulated near the Number 6 reactor to a temporary storage tank.

Tokyo Electric Power Company, or TEPCO, is expected to start moving the water in the turbine house of the No. 6 reactor to the tank on Sunday afternoon.

http://www3.nhk.or.jp/daily/english/01_15.html

Is the number 6 leaking also?

 

[fluutekies]

I'm neither a nuclear engineer nor a professional translator, but it says that in addition to the original 9x9 B-type fuel assemblies, it is adding 96 assemblies (also 9x9 B-type) which contain a higher proportion of gadolinia.
The original uranium fuel has a concentration of about 3-5% by weight of gadolinia, and the new fuel will have 5-7%.
The gadolinia acts as a neutron absorber, and will improve the ability to control reactions within the reactor.

Source:
http://www.tepco.co.jp/cc/press/10112901-j.html

Sounds like it might have something to do with what fluutekies is talking about.

Found my source: The GE non-public document on BWR (originally posted somewhere else & linked deep down elsewhere in this thread ): http://cryptome.org/0003/ge-bwr6.zip see section 3 on core design and configuration & use of Gd-oxide.

 

[zapperzero]

http://youtu.be/kO0flpwmjJI

Can anyone translate this videos?

Yep. http://ex-skf.blogspot.com/2011/04/fukushima-i-nuke-plant-ishikawa-of-jnti.html" did.

 

[georgiworld]

Yep. http://ex-skf.blogspot.com/2011/04/fukushima-i-nuke-plant-ishikawa-of-jnti.html" did.

What about the video you posted and I mistakenly re-posted? Is there a translation of that?

 

[rowmag]

Can't be. The number of channels in the core where bundles (assemblies) go is fixed, no?

I think they meant that they were replacing some low-gadolinium assemblies with the new ones.

 

[MadderDoc]

Well, the mystery thickens.<..>
What was the date of the photo showin the Mickey Mouse ears?

It was March 11th, at approximately 16:00. It is a frame from the video shot from a helicopter shortly after the tsunami, see for example this version of the video:
http://www.dailymotion.com/video/xhsf3e_new-film-of-tsunami-aftermath_news

There's perhaps disappointingly little mystery in it. If one takes account of the poor quality of the video from March 11th, and its being shot in a more oblique angle, it appears to be showing the same as the photo we have from March 12th:

Note: The image in the center has been subjected to the shearing/perspective tools of Gimp, in order to correct for the more oblique angle it was taken, so as to ease comparison.

 

[rowmag]

No way it would be extream radioactive, and it would melt without cooling.
About unit #4. This is possible that they were repleacting core shroud, reactor 4 was shout down and defueled becouse there was some crack in core shroud, so this would be possible that they were repleacing it. There is no much space, but look on this photo:

That is a water heater (pre-heater?) that is being replaced with a more corrosion-resistant type.