Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[jlduh]

@rhody: to my knowledge, the russians were planning to install a big cooling system below the core and that's why they made this tunnel below the reactor with a big room. But finally they didn't do it (why? Maybe not enough time?) and filled the room with concrete to increase the protection towards the phreatic water. The corium finally stopped his way before any contact to water. I don't know if some data have been released since on how deep it went and stopped.

For those new to the forum, i put again the link towards the video "The battle of Tchernobyl" in english (i found a direct complete version in one part on google videos instead of the previously 10 parts on you tube):

http://video.google.com/videoplay?docid=-5384001427276447319#

In the case of Fukushima plant, it seems that the concrete below the reactors ("radier" in french, don't know the name in english sorry) should be around 8 to 10 meters thick, some experts here talk about a speed of progression (very dependant on many factors anyway) of the corium in the concrete of around 1 meter per 24h (which is impressively quick). Anyway this shoud be quickly seen from outside because there shoud be a big amount of gas released from the interaction.

But again, the big fear is water + corium. And this can be before it contacts the concrete. Hope not.

 

[Gilles]

I think the only way for the corium to cool and recrystallize is to increase the surface/volume ratio, so that the inner warmth produced by the remnant RA can be dissipated at a small enough temperature. I understand that this happened in Tchernobyl - once the vessel was breached, the corium flowed in the basement and spread sufficiently to solidify. I guess it is a desperate enterprise to try to confine the fuel into the reactor with broken cooling system - the only possible way is to let the corium melt and go underground, hoping it will spread enough to cool and be stopped by the concrete slab - and not meet the water table.

 

[jlduh]

Hi Gilles, as you can see in France newspapers are clearly changing their mood today concerning the crisis, the optimism of the last days ("we switched on the light in control rooms") is sliding to something slightly different...

As is said earlier, to some extent the Tchernobyl accident, even worse from "scratch standingpoint" (explosion at full power -reactivity accident- with no containment and big graphite fire), presented to my opinion some advantages (i hesitate to use this word, really, but let's do it: it's not "absolute" words but "relative" words...) for the later stages of the accident. The core was fully opened and probably dispersed, which let more possibilities i think to cool it, also the dispersion helped to some extent avoiding having a big concentrated mess. I know that all the experts are saying that containment is far better than no containment but as i foresee the possible scenarios, I'm wondering until where this statement is true when we go to extreme meltdown, especially when anyway the containement has failed... and that you have big pools and water close to it at the very bottom.

Is the advantage still an advantage? Not sure, but I would like to be convinced by others of the the opposite...

As i understand the moves and "improvements" in the newest generations of reactors (like EPR in France), it's clear that after the TMI and Tchernobyl accident they considered these things as more probable and tend (if I'm not wrong) to reduce at the maximum the amount of water close to where the core could melt and as you said to design the thing so a melted core could lay down on a big surface like in a cendar (coated with ceramics in the EPR). Im' not saying that this is better (because it's also much bigger power in one reactor...) but at least this is from what they analysed as sufficiently risky to make changes. This can inform us a little bit on the current situation.

 

[rhody]

I think the only way for the corium to cool and recrystallize is to increase the surface/volume ratio, so that the inner warmth produced by the remnant RA can be dissipated at a small enough temperature. I understand that this happened in Tchernobyl - once the vessel was breached, the corium flowed in the basement and spread sufficiently to solidify. I guess it is a desperate enterprise to try to confine the fuel into the reactor with broken cooling system - the only possible way is to let the corium melt and go underground, hoping it will spread enough to cool and be stopped by the concrete slab - and not meet the water table.

Gilles, jlduh,

Thanks for the corium background, I understand the potential risk it poses if exposed to water. I think we need an expert opinion here, Astronuc, Dean would you care to inform us on what our options are at this point ?

Rhody...

 

[Lefteris]

Thank you all for your information and opinions on the situation. It really is not looking good, and as you all said it basically boils down to personal choice whether to leave Tokyo or stay. For now at least it seems safe to drink tap water with 51 Bq/kg (having fallen more since yesterday's 71 Bq/kg) as reported by Kyodo news agency here: http://english.kyodonews.jp/news/2011/03/81023.html


I will definitely keep reading this thread to try and get a better understanding of the situation and the dangers posed to me and my loved ones here in Tokyo so that we can make well informed decisions.

 

[havemercy]

If what you are saying since this morning is right, they have lost 10 days in triyng to cool down the reactor number 3 in stead of (if this was possible) going in the basement of the reactor to evacuate the water and/or to arrange a tunnel in the soil as they have done it in Tchernobyl.

The soil there is a tectonic one, so they must have installed very solid basement to suport the weiht of the reactor, i. e. more that the 8 - 10 meters you are quoting.

Don't we have the plans or photographs of the construction of reactor number 3 ?

Also the consumption of the concrete by the corium should have released very high quantities of smoke, charged with specific radioactive elements, which so far has not been observed if i am not wrong.

 

[AtomicWombat]

What is this feature? It looks like the top of a whiskey distillery. Note the round opening at the top.

If it is indeed the the top of the reactor it is in the wrong place, suggesting the reactor was destroyed by the explosion in building 3, which has been my "best guess" for some time.


Sorry if this has already been commented on; I've been away for a few days.

 

[jensjakob]

I think that the round feature is the top of the tank just above it

 

[jlduh]

For Japanese people on this forum, i repost this recent (MArch 23) radioactivity study posted earlier here, from US campaign, it clearly shows that the North/North west zone of Fukushima has been so far the most contaminated probably because of winds and/or winds+rain.


http://www.slideshare.net/energy/ra...om-fukushima-area-march-22-2011?from=ss_embed

http://energy.gov/news/10194.htm

 

[artax]

Fascinating analysis and discussions on here.
The containment explosion hypothesis seems a likely explanation for the multiple explosions heard during the reactor 3 event. ie pop 1 being the pressure vessel, pop2 being the primary containment, and then pop 3 being the unpressurised hydrogen in the roof void. Although I would not have expected such large durations between each pop, and there are no visible signs of 3 independent explosions.

To add another area of curiousity, has anyone considered what the grey area that appears to have emanated from reactor 3?

http://patrick.reformstudios.com/p.jpg

I know I'm going back a long way here, but this grey stuff (did you work out what it was?) seems to have been ejected in two directions 180 degrees apart Not quite perpendicular to building layout) as there's some on the roof of the building bottom right, that I think has a hole in it (out of shot). the hole suggesting this material to be either very heavy or very hot.

 

[|Fred]

I can hardly see how one would prefers No containment, full dispersion, combustion.
I really should not brag, but I feel that the press you are mentioning, has a really narrow understanding on the matters at hand.

The 10 000 time higher radioactivity of the water found lately, compare to the radioactivity found in a working reactor, was to be expected: We knew from the start that some Rod melted..
Now we have an indication of a recent leak in the containment (somewhere)

 

[artax]

There's some new video of the reactors from Russia today here:-

http://www.youtube.com/watch?v=97IRb3PH-Gk&feature=player_embedded

seem to be edited from here

http://www.youtube.com/user/YomiuriShimbun

and is it currently snowing over there or is that stuff emanating from the reactors?

It was snowing! ;-)

 

[curie]

Has anyone heard officially that there has been an upgrade to INES level 6? I've seen it around the web but it doesn't seem like a formal announcement.

 

[rhody]

Thank you all for your information and opinions on the situation. It really is not looking good, and as you all said it basically boils down to personal choice whether to leave Tokyo or stay. For now at least it seems safe to drink tap water with 51 Bq/kg (having fallen more since yesterday's 71 Bq/kg) as reported by Kyodo news agency here: http://english.kyodonews.jp/news/2011/03/81023.html


I will definitely keep reading this thread to try and get a better understanding of the situation and the dangers posed to me and my loved ones here in Tokyo so that we can make well informed decisions.

Lefteris,

I am glad you found us, I just did a google search on the title to this thread and it came up in the top ten list, and to PF's credit , the folks here strive to provide as accurate and timely information as possible. I did a thread contribution count and it is over 250 members (many new because of the reactor disaster) and climbing (no bad pun intended).

Rhody...

 

[havemercy]

Following french ASN, the cooling of reactor n° 3 with pure water failed.

"Communiqué de presse n°20 du 25 Mars 2011 à 10h00
25/03/2011 10:46"

"L’exploitant poursuit par ailleurs l’injection d’eau de mer pour refroidir les réacteurs n°1, 2 et 3. Une tentative d’alimentation du réacteur n°3 en eau douce a échoué, vraisemblablement en raison des conditions radiologiques d’intervention. "

http://www.asn.fr/

 

[Borek]

and is it currently snowing over there or is that stuff emanating from the reactors?

IMHO it is snowing, it is visible both in closeups and in some more general views. After all it is March 23rd, so nothing unusual.

 

[jlduh]

Ok, i would like to bring some more material here. Lots of things to summarize.

The first thing is that i just captured several shots from the live NHK world when they were talking about the 3 workers injured in the basement floor beacuse of the contaminated water. They we're asking a specialist from Tokyo University where this water could come from and he had a nice drawing which i think is a new important element for our analysis here because it seems quite accurate, and it's a transversal cut view through the reactor and turbine building. I let them big if no problem for the forum admins because it's much easier to see some details (the resolution is not excellent).

I post them first and will add infos and comments after.

1
http://www.netimago.com/image_182135.html

2
http://www.netimago.com/image_182136.html

3
http://www.netimago.com/image_182137.html I have a 4th one which completes the overall view of the buildings and layout which is a view from the top, a cut view also, at the level of the basement (i would say at the ground level approximatively).http://www.netimago.com/image_182143.html

Position of the workers injured by the highly contaminated 15cm to 30 cms water laying on the floor:

A) Based on the infos the guy from Tokyo University gave, the 3 workers were in the lowest room, between the torus room (on the left) and the turbine (on the right), where the blue pipe linking the reactor anf the turbine (steam pipe) goes down (on pictures 1 to 3).

B) the guy situated them on the other drawing (picture n°4) close to the big red inscription at the bottom right of the image (so quite far away from the reactor position).

The specialist interviewed also said that he doubts the water could come from the spent fuel pool (because of the level of contamination), but said it could come from a broken pipe coming from the reactor. He also said that the day before, an other shift reported no water here. Very surprisingly (for me), then didn't evoke the possibility that this water could also come from the suppression pool which is almost at the same level just behind the wall on the drawing...

These drawings give some interesting informations, we see the level at which the suppression pool is installed (quite deep under the ground) but we also see that the turbines are actually well under the ground either!

That's really scary when you think about risks of flooding... By the way, this probably means that seeing the flooding of the plant from the helicopter shot (just after the tsunami), these rooms have been flooded also? What do you think? Then they would have needed to empty them which could explain the time spent to access these areas?

I'm very surprised to see this kind of layout for the turbine an connecting buildings...

Right AntonL, we were guessing pretty well with the bits of infos everybody brings here. The puzzle is assembling.

Something else: looking at all these new informations on what's inside, i relate the position of the turbines and the position of the big hole in the roof of this turbine building: was this hole done by a big debris coming down after the explosion or was it done DURING the explosion by one of the turbines just blowing out? The hole is right at the top of the turbines:

http://www.netimago.com/image_182148.html

EDITED: Coming back to the relative level of the torus and the turbine to the ground level, one can evaluate how deep these are below the ground level: the reactor vessel is (if no mistake) around 5,4m in diameter, the bottom of the torus (which not so far in diameter than the RPV) seems then to be at around -1,5 (and even more?) "reactors diameter" below the ground (sorry for this approximate unit of measurement, but at least no conversion units problems!). From the TEPCO tsunami study (which proved exact in showing the buildings below the ground! I was not understanding this... and not believing it! But their scale is misleading: the height of the platform relatively to sea level seems as high as the reactor building, which is obviously untrue!)

http://www.netimago.com/image_182149.html

we got the info that the platform was at +10 to +13m from sea level. Soooo... do you come to the conclusion that the bottom of the plant floor (which is visibly the torus supported by concrete plots) is probably only a few meters above actual sea level?

 

[Gilles]

Also the consumption of the concrete by the corium should have released very high quantities of smoke, charged with specific radioactive elements, which so far has not been observed if i am not wrong.

I don't really know what happens when corium meet a concrete slab - I think of some kind of reaction between silicates and molten metals, leading to further fusion of the slab. Not sure it is supposed to emit a lot of smoke : black smoke is usually associated with incomplete combustion of organic materials with emission of fine carbon particles (soot)- well they may be some rubber, isolated (!) cables, and so on, under the reactor, but I'm not sure this represents a large amount of material.

 

[AntonL]

Ok, i would like to bring some more material here. Lots of things to summarize.

The first thing is that i just captured several shots from the live NHK world when they were talking about the
3 workers injured in the basement floor beacuse of the contaminated water. They we're asking a specialist from
Tokyo University where this water could come from and he had a nice drawing which i think is a new important
element for our analysis here because it seems quite accurate, and it's a transversal cut view through the reactor
and turbine building. I let them big if no problem for the forum admins because it's much easier to see some details
(the resolution is not excellent).

I post them first and will add infos and comments after.

I have a 4th one which completes the overall view of the buildings and layout which is a view from the top,
a cut view also, at the level of the basement (i would say at the ground level approximatively).http://www.netimago.com/image_182143.html

Position of the workers injured by the highly contaminated 15cm to 30 cms water laying on the floor:

A) Based on the infos the guy from Tokyo University gave, the 3 workers were in the lowest room,
between the torus room (on the left) and the turbine (on the right), where the blue pipe linking the reactor
anf the turbine (steam pipe) goes down (on pictures 1 to 3).

B) the guy situated them on the other drawing (picture n°4) close to the big red inscription at the bottom
right of the image (so quite far away from the reactor position).

The specialist interviewed also said that he doubts the water could come from the spent fuel pool (because
of the level of contamination), but said it could come from a broken pipe coming from the reactor. He also
said that the day before, an other shift reported no water here. Surprisingly (for me), then didn't evoke the
possibilty that this water could also come from the suppression pool which is almost at the same level...

Not Bad - https://www.physicsforums.com/showpost.php?p=3207270&postcount=1045"

OK I made a mistake I thought is as upper level but now we know it is the basement

 

[|Fred]

I would like to point out a few thingy

March 20th
Reactor 3 Pressure = 250-290 KPa
PCV Pressure= 310 Kpa
Suppression Pool Pressure = over 400 KPa out of scale

Preparation to lower the pressure was carried. Judging from the situation, immediate pressure relief was not required.

March 23
Reactor 3 Pressure = 135-0 KPa
PCV Pressure= 100
Suppression Pool Pressure = down scale

March 24
Reactor 3 Pressure = 142-0 KPa
PCV Pressure= down scale
Suppression Pool Pressure = down scale

March 25th
Reactor 3 Pressure = 139- 0 KPa
PCV Pressure= 107 Kpa
Suppression Pool Pressure = 194 KPa
===========================================

I think that the Reactor pressure sensors are compromised, one likely dead.
the Down scale indicated a dé pressurization of the PCV.

 

[AntonL]

I
I think that the Reactor pressure sensors are compromised, on likely dead.
the Down scale indicated a dé pressurization of the PCV.
taking into considération the recent leak , It seems possible that both PCV and and Reactor are both compromised since the 20th

It must be a relative slow leak, I would imagine a valve not holding the pressure
and now the contaminated steam is escaping, which condenses to the water
the basement acting as a containment area.

 

[havemercy]

Sorry to step back regarding the neutrons. I heard that the water has the effect to slow down the speed of the neutrons.

If this is correct, in the Spent Fuell pool, the neutrons with high speed will go through the fuell without making contact with the fuell and thus reduce the nuclear reaction.

If they add water, it will reduce the speed of the neutrons that will making more contact with the fuell and then increase the nuclear reaction.

The fact to put water in the pools will accordingly have the effect of making more nuclear reaction, isn't it correct ?

 

[|Fred]

It must be a relative slow leak, I would imagine a valve not holding the pressure and now the contaminated steam is escaping, which condenses to the water
the basement acting as a containment area.

I edited my post as I did not gave it enough sensible thoughts :)

 

[jlduh]

@Havemercy: my understanding is that water (not bored of course) increases the reaction and that steam reduces it, and that this is a way to control the reactivity and the reactor in a BWR. But answers from specialists would clarify that...

 

[Maclomer]

In all of the reactors (setting aside the spent fuel pools) the absolute imperative is to maintain cooling by whatever means is feasible and, however it is done, active cooling will probably be needed for many months.

Right now we know some of the cooling is done by directing water jets onto the exterior of the containment and the runoff will go into the ocean. If the containment is breached, that runoff will be radioactive so then there is bound to be a continual emission by this route. Unavoidable.

Now my question:
To what degree is cooling water, and so it seems, seawater, being injected directly into the cores (for example Number 3) and is this water is being heat-exchanged in a closed loop; or are they injecting the water and then allowing the steam to escape (people have commented here about salt build-up)?

I ask this because, at the same time, we hear about 'restarting the cooling pumps', especially for Number 3, using this newly laid power line, which implies to me that an intact cooling loop with proper heat exchange may still be possible, at least for some of the reactors.

 

[Gilles]

I think water in general increases the reaction rate by slowing neutrons. It's just that water vapor is much less dense than liquid, so the effect of steam is to decrease the rate relative to liquid water (negative void coefficient). In reactors using graphite as a moderator like RBMK , it was positive , because water acted essentially as neutron absorber and not as a moderator. That's the same for Pu-Na fast breeder ...

 

[|Fred]

Reactor 1 (not compromised) but under heavy stress
Reactor 2 stabilized (may be wishful thinking)
Reactor 3 (compromised, not necessarily the vessel it self may be only in the pipe of the cooling system and the containgment)

 

[artax]

There's a long but interesting doc. here on spent fuel storage (wet and dry):-

http://www-pub.iaea.org/MTCD/publications/PDF/te_0944_scr.pdf

 

[TCups]

Studied some nuclear chemistry at uni a long time ago hence my interest but I would have to research those isotopes.
However the news here did mention that the ALLOWED UK levels for infants in tap water used for drinking (making up milk) are 5 TIMES HIGHER than those allowed in Japan... so I wouldn't worry at all.
The main reason Iodine is important is because the body has some in it always (thyroid gland) and can't tell the difference between the active isotopes and the natural ones. So if you take the Iodide pills, the iodide atoms (ions) just displace the radio ones very quickly before they've been their long enough to have any effect.
I'm pretty sure the authorities are tellining the truth about the tap water, and washing with it will be no problem at all... and drinking!
If I was in Japan now, I would just avoid the exclusion zone and don't go swimming in the sea!

RE: IODINE PILLS & IODINE UPTAKE BY THE THYROID

Normal iodine will not, I believe, displace radioactive I-131 that has already been taken up by the thyroid gland. The purpose of the iodine pills is to effectively flood the normal biologic uptake of trace amounts of iodine with the normal, non-radioactive isotope, and suppress any further uptake of iodine, ie, radioactive iodine, by the thyroid. After a large dose of RAI (radioactive iodine), potassium iodide will do little good.

 

[Reno Deano]

Thanks Reno, so your explanation is that it's because there was no power available...

So the only vent they could open was inside the building, there was none actionnable toward the outside (what a pity...). Then that was a constraint, not a choice (like to avoid radioactive venting outside), right?

Are we talking about a valve that a man had to actionnate physically being close to it?

The reason why I'm asking these questions is that it seems that a modification has taken place in the US after the TMI accident under the NRC requirement, with the installation on all BWR reactors in the US of a so called "hardened vent" which is a direct realease to the atmophere to depressurize the containement. THis was to avoid precisely H2 release inside the building. Then the question is: did the japanese had this hardened vent? I have the impression that these vents are the big structures (like antennas) that we see close to every reactor (right or wrong?) but in this case it means that they still couldn't activate them because no power (seems not to "hardened" to me but...).

The Reactor Accident off gas system (shielded filtration - carbon and HEPAs) is within the reactor building. I am assuming it worked until the station black out. Then the valves failed shut. I do not know if they had hydrogen igniters on the system (but doubt). The system is located above the reactor vessel level of the plant. That could have been the location of the first expolsions and when damaged the gas vented naturally to the reactor building via numerous paths, eventually finding their way to the top of the reactor building (reactor work platform area). The other off-gas system is the normal one that allows filtration and decay of radioactive short lived gases and is generally under ground with a long decay loop before heading for the stacks. I have inplant experience with several of the BWR models, but am getting long in the tooth, and my memory gets sketchy at times. Also, I have little patience with conjecture based on hearsay and not facts.

The beta exposures while high are not approaching any significant Equivalent Whole Body Dose. Cobalt therapy cancer patients received significant burns of their skin when treated. Since the workers dosimetry did not likely measure beta radiation, the concern was based on isotopic knowledge of the radioisotopes in the water and the large penetration radiation component, and the fact that their boots were full of water. Beta exposure is measured in Grays anyway and depending on the amount of skin involved (largest organ of the body) is converted to Equivalent Whole Body dose at some later time, if significant.

 

[Astronuc]

Sorry to step back regarding the neutrons. I heard that the water has the effect to slow down the speed of the neutrons.

If this is correct, in the Spent Fuell pool, the neutrons with high speed will go through the fuell without making contact with the fuell and thus reduce the nuclear reaction.

If they add water, it will reduce the speed of the neutrons that will making more contact with the fuell and then increase the nuclear reaction.

The fact to put water in the pools will accordingly have the effect of making more nuclear reaction, isn't it correct ?

The spent fuel pool is there to store the discharge fuel for some period of time to allow the fuel to cool down thermally (allow decay heat to dissipate) and to allow the decay of short-lived radioisotopes (to reduce the radiation levels). The SFP also must provide for full core offload, which includes the reinsert fuel (fuel to be returned to the core), as well as the discharge fuel.

Water also provides shielding from gamma and beta radiation.

Water is also a moderator. A moderator slows fast neutrons to 'thermal energies' (mean neutron kinetic energy ~ 0.025 eV or speed of 2200 m/s). The fission cross-sections of U-235 and Pu-239 increase as the neutron energies approach the thermal energy of ~0.025 eV.

However, the SFP is designed to be subcritical. The walls of the spent fuel pool contain neutron absorbing material, usually a compound of boron with B-10, e.g., boraflex or boral. The water in the SFP can be borated, but in theory the SFP should be designed to remain subcritical if all the water is pure, i.e., without any boron, particularly for BWRs by design. As long as the boron in the walls of the spent fuel pool remain intact, the pool should not be able to achieve criticality.

For BWRs, the water in the SFP is the same as the water in the reactor cavity when the core is open for refueling. Movement of irradiated fuel is done with the fuel underwater - at least 7 m or so, as the reinsert and discharge fuel is moved between the core and SFP. Boric acid is not used in BWRs, so the SFP water would not contain boron.

 

[Astronuc]

Now my question:
To what degree is cooling water, and so it seems, seawater, being injected directly into the cores (for example Number 3) and is this water is being heat-exchanged in a closed loop; or are they injecting the water and then allowing the steam to escape (people have commented here about salt build-up)?

I ask this because, at the same time, we hear about 'restarting the cooling pumps', especially for Number 3, using this newly laid power line, which implies to me that an intact cooling loop with proper heat exchange may still be possible, at least for some of the reactors.

Ideally the cooling systems would remain closed, but that may not be the case where the units are venting steam. In addition, if there are open valves, then water may be leaking out. Leaking would certainly be the case if any of the piping, valves, or pumps, attached to the primary systems has ruptured.

Using seawater is problematic from the standpoint of corrosion, as well as the salt. Corrosion products can be transported in the primary circuit and attached systems. Salt may concentrate in areas where boiling/evaporation occurs. Salt and corrosion products may deposit in valves and seals, thus preventing the tight closing of valves or undermining the seals.

 

[Reno Deano]

Neutron Beams. During fission neutrons are scattered 360 degrees. As Astronuc can confirmed it takes a collimator to focus and make a "neutron beam". Also, the location of the various sources of neutrons (core and SFP) provides significant attenuation of neutron external to the sources. As much Boron as there is in both locations a neutron beam is highly improbable. Side Note: When we were starting up naval reactors for the first time, Rickover would bring out the first neutron to start the plant. :-)

 

[jlduh]

I would like to draw your attention to a last remark i just made (and it probably answers a question I've had for some time looking at the images of the ruins of the reactors). Looking from outside of the reactors, we assumed maybe that they are centered in the middle of the reactor building. I've seen variations on the differents schematics that have been posted around but if the drawing that the scientist from Tokyo University showed at the NHK is correct, which i believe it is, then it confirms that THE REACTOR IS NOT AT THE CENTER OF THE BUILDING VIEWED FROM THE TOP, but pushed towards the turbine building (because the east side of the torus below the ground is actually below the connecting building and not below the reactor building). So the reactor head is shifted towards the East (toward the sea).

Now we can try to speculate if the smoke plume from this building is coming from this place or not, but if think it is (satellite picture just after the explosion, 14th or march):

http://www.netimago.com/image_182152.html

http://www.netimago.com/image_182153.html

 

[jlduh]

@TCUPS: did you have a look at my post just above yours and at my other post with the big captures of the drawings on the NHK TV at page 72 of the thread?

Because i think they answer some of your questions concerning the basement, the location of the workers and water, the location of the basement relative to sea level,and confirms also your remark concerning the shift of the reactor towards the East side of the building, and the corresponding smoke position...)