Japan Earthquake: Nuclear Plants at Fukushima Daiichi

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The Fukushima Daiichi nuclear plant is facing significant challenges following the earthquake, with reports indicating that reactor pressure has reached dangerous levels, potentially 2.1 times capacity. TEPCO has lost control of pressure at a second unit, raising concerns about safety and management accountability. The reactor is currently off but continues to produce decay heat, necessitating cooling to prevent a meltdown. There are conflicting reports about an explosion, with indications that it may have originated from a buildup of hydrogen around the containment vessel. The situation remains serious, and TEPCO plans to flood the containment vessel with seawater as a cooling measure.
  • #2,611
|Fred said:
*cough*
I've king of have said so since friday (including a nice picture showing the overhead crane), I even sent Gunderson a letter Friday after noon asking him to reconsider the mistake he made.
https://www.physicsforums.com/showpost.php?p=3223712&postcount=2408

now the isse we have is that i suspect that the 2 crane caved in and we may face a new disaster if the fuel handling crane is further push down into the pool
letter? try e-mail contact@fairewinds.com from http://www.fairewinds.com/content/contact-us

I have found a higher resolution picture of the one you used in your post

image-198534-galleryV9-orwt.jpg
 
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  • #2,612
|Fred said:
*cough*
I've king of have said so since friday (including a nice picture showing the overhead crane), I even sent Gunderson a letter Friday after noon asking him to reconsider the mistake he made.
https://www.physicsforums.com/showpost.php?p=3223712&postcount=2408

now the isse we have is that i suspect that the 2 crane caved in and we may face a new disaster if the fuel handling crane is further push down into the pool

Yes. I remember you saying you had emailed Gunderson, and I remember your saying there was a better view from a horizontal perspective that showed the FHM above the pool.

What drew my response today was the Mar 31 video where Gunderson describes the empty fuel rack being exposed -- I don't remember that being discussed before. If it was, I missed that part, so apologies. Anyway, the photo I posted clearly refutes G's assertion that the object in his video described is the top of an empty fuel rack. Had you made that point also?

I don't think the position of the FHM has changed between the two photos you now repost -- one fisheye lens view, one helicopter view. I will look some more, but I can't see it.
 
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  • #2,613
Yeah by letter I meant email ;)

anyhow.. we have a FHM ant its crane that felt is partially into the pool, the top of the rods should be one floor below. What M Gunderson thought were top of rods were wreckage fallen on the FH crane.
The "rails" belong the the Top crane and are safety rail
I've corrected somehow the perspective and of the fish eye footage on the picture bellow

[PLAIN]http://k.min.us/ikAnyu.jpg
 
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  • #2,614
REGARDING THE PICTURES WE HAVE BEEN DISCUSSING, INCLUDING THE AMOUNT AND LOCATION OF RISING STEAM AND POSITION OF THE FHM & OVERHEAD CRANE

Borek said:
Not necessarily. Amount of steam appearing is a function of water temperature, air temperature and humidity. I have seen steaming water that was lukewarm at best.

I put the front edge and east end of the SFP about where I have drawn the red line. I see steam rising from between the front edge of the SFP and the FHM, which has been advanced to the front of the SFP. I wonder if this was to allow the overhead crane to lift the fuel rod assemblies that were to be transferred laterally to the smaller "cask" pool to the west. In the photos and diagrams I have seen, it doesn't look like the FHM goes over the cask pool, only the overhead crane appears to go there.

Look at the far right end of the FHM -- there is a "hockey stick" green structure you can clearly see in both the photo of the undamaged FHM and the FHM over the pool in Bldg 4. You can use it as a point of reference. It is above the pool in both photos of Bldg 4.

http://i306.photobucket.com/albums/nn270/tcups/FHM.jpg

http://i306.photobucket.com/albums/nn270/tcups/Picture36.png

http://i306.photobucket.com/albums/nn270/tcups/Picture18.png

and again, in the diagram I altered (moving the cask from the shaft to the cask pool), it looks like the FHM is at the front edge of the SFP, and that the overhead crane would be used to transfer fuel from the SFP to the cask, and the cask to the shaft.

http://i306.photobucket.com/albums/nn270/tcups/Picture30-4.png

If that operation were interrupted, and fuel had been loaded into the cask, I again propose that it was the cask loading pool where the explosion and most of the damage centered, and that that explains

1) the damage along the shaft, its north and west sides on the external portion of the building,

2) a vertical component straight upward and to the east through the connecting shoot (but much smaller than at Bldg 3), and

3) access of the explosion's energy to the lower floors and to the structurally weakened northeast corner of Bldg 4.

4) the thick walls of the SFP4 (except at the narrow transfer chute) would have protected the SFP, although water would not now hold in the SFP4 above the level of the transfer chute to the cask loading pool

This is the only thing I can come up with that fit everything I see, from the position of the FHM, to the position of the overhead crane, to the internal and external damage to Bldg 4, and to the apparent need to clear high level waste on the ground before bringing in the long-armed crane to spray water and get a look down into the SFP4.

http://i306.photobucket.com/albums/nn270/tcups/Picture31.png

Debunk that, please.
 
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  • #2,615
TCups said:
http://i306.photobucket.com/albums/nn270/tcups/Picture18.png
What is the arrow pointing at ?
 
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  • #2,616
TCups said:
REGARDING THE PICTURES WE HAVE BEEN DISCUSSING, INCLUDING THE AMOUNT AND LOCATION OF RISING STEAM AND POSITION OF THE FHM & OVERHEAD CRANE

If that operation were interrupted, and fuel had been loaded into the cask, I again propose that it was the cask loading pool where the explosion and most of the damage centered, and that that explains


Debunk that, please.

There are so many IFs to this that I'd rather you try to prove some of the ifs than anyone try to "debunk" this.

1) IF they were even using casks

2) IF that diagram is representable of fukushima

3) IF there is a pool at that location

4) IF that pool is used to loading spent fuel

5) IF they were loading hot fuel into casks at the time of the earthquake

etc. etc.

You do post some interesting speculation but you are building assumptions on assumptions which is not really credible. You could build any number of different scenarios like this that could produce the results we've seen.
 
  • #2,617
|Fred said:
What is the arrow pointing at ?

The same piece of debris that shows up over Gunderson's empty fuel rack in his video. I confess that I hadn't seen G's video until this morning because I dismissed the issue of the FHM falling into the pool after seeing your earlier photos posted. Only after I saw a repost of it this morning and compared to the fisheye video did I realize I could identify the structure in question and prove it to be something other than an empty fuel rack. Had you realized that before?

Also, to my "debunk this" scenario, I forgot to add -- two cask trucks were parked out back and at least one of them was empty.
 
  • #2,618
Maxion said:
There are so many IFs to this that I'd rather you try to prove some of the ifs than anyone try to "debunk" this.

1) IF they were even using casks

Two cask trucks are parked out back in many of the initial satellite photos. At least one of them is empty.

2) IF that diagram is representable of fukushima

I can find no credible evidence that the basics are not the same, right down to the tunnel access on the west side of the bldg and the position of the cranes and SFP. Fred, I believe, has superimposed a schematic drawn from the diagram on the side of Bldg 3 and matched it up pretty nicely. I have superimposed a schematic from the diagram on the overhead shots of Bldg 3 and 4 and it matches pretty closely. As best I can tell from the photos of the undamaged insides of the buildings, from the structures I can see, they seem to match.

3) IF there is a pool at that location

It seems credible there would be a pool for the purpose of the overhead crane to transfer and load casks if I understand the basics of that operation as has been explained to me earlier on this site. It is true we don't have a picture of that small pool to go by.

4) IF that pool is used to loading spent fuel

IF the diagram is correct, what other possible function might it have, please? How else do they get the spent fuel to the 7th large storage pool out back? FedEx?

5) IF they were loading hot fuel into casks at the time of the earthquake

etc. etc.

Truck, cranes, etc. etc.

You do post some interesting speculation but you are building assumptions on assumptions which is not really credible. You could build any number of different scenarios like this that could produce the results we've seen.

My assumptions and assertions ARE CREDIBLE. It is the nature of this kind of photographic forensics that assumptions have to be made and then proven wrong to eventually arrive at a scenario that explains all the visible evidence and known facts:

The visible damage to the buildings, the two trucks out back, the existence of a separate, 7th storage facility where a lot of the sites fuel rods have been transferred to in the past, the location of the overhead crane and the location of the FHM, and the apparent dozer work done before that water hose boom were placed are FACTS, not assumptions.

Try not to attack my credibility, please. Try to attack the evidence I propose and tell me WHY those assumptions and conclusions have to be wrong. Thanks.

(I do love a good puzzle to solve, it's true. :devil:)
 
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  • #2,619
AtomicWombat said:
I've inadvertently openned a can of worms. It appears there is huge disagreement on the population health impacts of Chernobyl in the scientific literature.

A large Russian study from 2007 was translated and published in 2009 in the Annals of the New York Academy of Sciences, a prestigious journal. It is available here:
http://www.strahlentelex.de/Yablokov%20Chernobyl%20book.pdf"

This Russian study reviews over 1,000 published research papers - most by Eastern European researchers written in Slavic languages - as well as a large number of internet and otherwise published documents on the consequences of the Chernobyl disaster. The authors claim that a large body of research literature from Eastern Europe has been downplayed or ignored by the IAEA.

Among other health and environmental consequences, the Russian study concludes, "...the overall mortality for the period from April 1986 to the end of 2004 from the Chernobyl catastrophe was estimated at 985,000 additional deaths."

In contrast, in 2005 the IAEA estimated about 4,000 Chernobyl-realted deaths.

The IAEA has been criticised (by Christopher Busby among others) as being biased by its pro-nuclear industry stance; whilst those supporting a higher estimate (eg. Busby) have been criticised as being biased by an ideology that opposes nuclear power.

See also:
http://www.huffingtonpost.com/amory-lovins/nuclear-power-fukushima-_b_837643.html"

I am a statistician with research skills, so I could review the literature myself, but it's an enormous task. So I'll simply point out there are two strongly opposed views with substantial backing.

By the way, those are not IAEA estimates, but UNSCEAR's and WHO's, who studied the effects directly on the field. Additionally, if I recall it correctly, the figure was about 2,000 including past and possible future premature deaths, and that is based on the greatly polemical LNT hypothesis. Many find that figure greatly exaggerated too and lacking any real evidence. So the ones you mentioned are not, by no means, the most pessimistic and optimistic estimates.
warren_c said:
FWIW.
This chart might be useful to those worrying about radiation exposure:

http://www.informationisbeautiful.net/visualizations/radiation-dosage-chart/

It puts radiation dose levels in perspective and in context. With out political bias from either side of the nuclear energy debate.

What Chernobyl grounds are the ones mentioned in that diagram? Those within the sarcophagus? It should be noted that Chernobyl nuclear power plant remained in operation until the year 2000. That dose rate would exceed maximum allowed yearly dose for workers in just a few hours, not to mention working there daily for 14 years.

This one is also an interesting and didactic http://xkcd.com/radiation/" about radiation doses.
Godzilla1985 said:
Cause of death was probably tsunami - victims showed lots of blood loss. Although, I don't recall hearing of two missing workers throughout this time, so I'm kinda surprised.
Those two workers were missing from the very beginning after the tsunami struck.
TEPCO: "Presence of 2 TEPCO employees at the site is not confirmed on March 11th."
WNN: "The whereabout of two Tepco workers remains unknown." (http://www.world-nuclear-news.org/rs_Battle_to_stabilise_earthquake_reactors_1203111.html" )
 
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  • #2,620
I just saw a video that shows they have started concreting some lower cavities in the bowels of one of the plants. Seems like a good idea to stop the leaks. Another way of doing it would be to build a ramp and run old radial tires filled with boron and concrete down a ramp into the pile of junk. Minimize worker exposure and get rid of used tires at the same time.
 
  • #2,621
My recollection of the information about unit 4 is that there were probably two (or more) explosions in the building. The first reports mentioned a side panel blown out and a hole in the roof. There was concern about the water level in the spent fuel storage pool and discussion about how to add water as the holes were not large enough or in the right position to direct water to the pool. Then pictures were posted showing the current state with side panels blown out and the entire roof missing. Reports of the fires were confused with some saying the first fire had been extinguished by workers and others saying it had subsided on its own. Speculation that lubricating oil had been burning - but never confirmed. Second fire was noted by workers outside but then subsided on its own. Explosions were inferred, but not documented by witnesses or photos - I assume because there was no one in the area when they occurred. The overall number of explosions at the plant remains a bit murky. One video of the unit 3 explosion has audio of three 'reports' or blasts, but other sites complained that the time delay (given camera location and speed of sound) was impossibly short and suggested the audio track had been edited. I believe the original video source was rTi - Russian news channel.

Interesting that the two dead workers were found in a lower control room servicing unit four. Not sure what they might have been doing there given the reports they were killed at the time of the tsunami.
 
  • #2,622
TCups said:
I realize I could identify the structure in question and prove it to be something other than an empty fuel rack. Had you realized that before?

I'm not following, what is it for you?
 
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  • #2,624
|Fred said:
I'm not following, what is it for you?[/]
@Fred:

The grid like structure is part of the deck of the FHM machine, ergo, it cannot be part of the empty spent fuel rack.
 
  • #2,625
From: NYTimes.com

Link: http://www.nytimes.com/2011/04/03/science/03meltdown.html

A very revealing Picture of Japan Crisis...

"A European atomic official monitoring the Fukushima crisis expressed sympathy for Japan’s need to rely on forensics to grasp the full dimensions of the unfolding disaster."

“Clearly, there’s no access to the core,” the official said. “The Japanese are honestly blind.”
 
  • #2,626
ACTUAL PICTURE OF THE SPENT FUEL POOL OF BLDG 3 (AT LAST!)

Thank you Anton.

Oops -- Major correction -- this video is not from Fukushima Diiachi (1970's vintage) plant. So, the photo from inside is not the current photo of Fukushima Diiachi Bldg 4. My mistake.


AntonL said:

Here is my annotated versions of the screen shot of the inside of Building 3 and the spent fuel pool, which appears to be viewed from the east side, looking west. Neither the fuel handling machine nor the overhead crane are visible, but you can clearly see the open shaft in the northwest corner, and, for the first time, what appears to be an accessory pool within the southwest corner of the larger spent fuel pool.

If it is a cask pool, then the function might be as follows (yes, I am guessing):

1) the gate to the cask pool is closed, water is pumped out.
2) an empty, dry cask is lowered into this smaller pool and readied for loading.
3) water is pumped back in and the gate is opened.
4) fuel rods are transferred from the SFP to the cask pool, by the FHM, through the open gate.
5) the cask is capped
6) the gate is closed, water is pumped out, and the FHM moves back out of the way
7) the overhead crane takes the cask of spent fuel up, out, over and down the shaft, and out the tunnel to a waiting truck, to be trucked as quickly as possible to the larger spent fuel facility, #7
8) the process is reversed and the cask is unloaded in the large SFP7

Any first hand knowledge of these operations, anyone?

http://i306.photobucket.com/albums/nn270/tcups/Picture38.png
 
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  • #2,627
TCups said:
ACTUAL PICTURE OF THE SPENT FUEL POOL OF BLDG 3 (AT LAST!)

Thank you Anton.



Here is my annotated versions of the screen shot of the inside of Building 3 and the spent fuel pool, which appears to be viewed from the east side, looking west. Neither the fuel handling machine nor the overhead crane are visible, but you can clearly see the open shaft in the northwest corner, and, for the first time, what appears to be an accessory pool within the southwest corner of the larger spent fuel pool.

If it is a cask pool, then the function might be as follows (yes, I am guessing):

1) the gate to the cask pool is closed, water is pumped out.
2) an empty, dry cask is lowered into this smaller pool and readied for loading.
3) water is pumped back in and the gate is opened.
4) fuel rods are transferred from the SFP to the cask pool, by the FHM, through the open gate.
5) the cask is capped
6) the gate is closed, water is pumped out, and the FHM moves back out of the way
7) the overhead crane takes the cask of spent fuel up, out, over and down the shaft, and out the tunnel to a waiting truck, to be trucked as quickly as possible to the larger spent fuel facility, #7
8) the process is reversed and the cask is unloaded in the large SFP7

Any first hand knowledge of these operations, anyone?

http://i306.photobucket.com/albums/nn270/tcups/Picture38.png

How can you call it actual photo, if its filmed at completely different NPP?
 
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  • #2,628
ah... I believed It was from the start I 've been trying to figure what else you thought id was
I'm not a ballistic & explosive expert but , I'm not convinced by your hypothesis
it does not fit imo the damage to any wall
[PLAIN]http://k.min.us/ikIW22.jpg
 
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  • #2,629
jensjakob said:
This picture worries me:
http://english.kyodonews.jp/photos/2011/04/82781.html

If the military takes these precautions - why do we still see workers on the ground in lot less protection?

I will take a stab at this. The personal pictured are operating the tug bringing a fresh water barge to the plant. They are approaching a known radiological contaminated area where winds may change the structural integrity of the plant may deteriorate or an aftershock (now >800) mat change the situation markedly in a short period with no notice. They must stay to task even in such an event since their vessel also presents a hazard to those present if not kept in control. Even if they are free of the barge at the time of a seismic event that shook loose radioactive material into the wind they are still out in the open (comparatively) and their best speed may be that of a herd of turtles.
liam
 
  • #2,630
ps: Kashiwazaki-Kariwa Nuclear Power Plant is and ABWR its layout is likely to be rather even more different than the Unit 6 of Fukushima is from the rest
 
  • #2,631
|Fred said:
ah... I believed It was from the start I 've been trying to figure what else you thought id was
I'm not a ballistic & explosive expert but , I'm not convinced by your hypothesis
it does not fit imo the damage to any wall
[PLAIN]http://k.min.us/ikIW22.jpg[/QUOTE]

Hmm - I have to agree, I guess. Back to the drawing board. . .

Where do you put the epicenter of the blast?
 
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  • #2,632
TCups said:
That has been suggested. Even so, to transmit the blast force downward with sufficient force to blow almost all of the walls one level below the top of the SFP4, and several wall panels two levels below, and yet leave most of the superstructure of the roof girders intact, and even have the north wall of the top floor collapse inward speaks to me of a very different kind of explosion, doors opened or closed. A lot of the damage is isolated around the northeast corner of Bldg 4.

I can maybe get to that kind of damage if hot fuel drops through the bottom of one or the other pools in the top floors and causes and additional lower level blast that spreads outward around the reinforced inner walls of the primary containment. But I just can't wrap my arms around the open door theory.

I mentioned in an earlier post that there may have been oxy/acetylene torches present due to the maintenance occurring in Bldg 4. I do not know the specific gravity of acetylene (would it settle to the floor) nor the velocity of its burn rate. I do know that a correct oxy/acetylene mix in a couple of small paper cups glued together make a dandy crack! It is very similar to hydrogen, (Re; misspent youth). There may also be many other flammable materials present that would never be allowed except during maintenance. I remember that acetylene is unstable at pressures above (8-14 psi) a very low pressure and will detonate if sealed in say a milk bottle and concussed with a .22 bullet.

All of the hazardous materials may have been overlooked in the midst of a 5 minute long quake as well as sources of ignition.
liam
 
  • #2,633
liamdavis said:
I mentioned in an earlier post that there may have been oxy/acetylene torches present due to the maintenance occurring in Bldg 4. I do not know the specific gravity of acetylene (would it settle to the floor)
C2H2 = 26 , very close to the average molar mass of the air (29), no reason to separate.
 
  • #2,634
Pics of Unit # 4 .
 

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  • #2,635
Pic of Unit 4 spent fuel pool and reactor .
 

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  • #2,636
Pics of unit 4 .
 

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  • #2,637
AntonL said:
Sorry for the double post - but this time with better pictures of >1Sv leak
Water has found its way by cable ducts from the reactor building to the sea
There seems to quite a head for the water to be ejected that forcefully and also note the steam rising - so it is pretty hot

(In my opinion this looks like a drain hole for cable drawing pit and not a crack)

[URL]http://www.asahi.com/photonews/gallery/fukushimagenpatsu2/images/0402_plant2.jpg[/URL]

[URL]http://www.asahi.com/photonews/gallery/fukushimagenpatsu2/images/0402_plant1.jpg[/URL]

[URL]http://www.asahi.com/photonews/gallery/fukushimagenpatsu2/images/0402_cement.jpg[/URL]

But the leak continues and access blocked by a couple of tons of concrete


[URL]http://www.asahi.com/photonews/gallery/infographics3/images/0403_pit2.jpg
[/URL]

Nice grab on the pics AntonL. As far as the 'stop the leak' operation goes, just backed up the concrete truck and dumped the 'mud' into the access manhole as best they could. Didn't even use a concrete vibrator, probably the contaminated discharge was/is to 'hot' no one wanted to get splashed. Concrete truck driver never gets out of his truck, pours the mud while looking at his rear view mirrors, gets done and says, "C-ya." Laborer #1, "Boss says to vibrate the concrete." Laborer #2, "Fuk-u, you go over there and vibrate it."
If the hole in the wall or crack was right there and accessible, just slide a sheet of plywood or steel plate down along the wall and see if the flow is affected or not.

The way unit 4 is leaning probably incurred more damage from the unit 3 blast as that was just a tremendous explosion(s). If unit 4 pool(s) are running low on water and hydrogen is being produced, does the volatile air mixture ignite spontaneously (like temperature reaction) or is a 'spark' ignition necessary? If the mixture needs a spark, then hydrogen could fully accumulate on all floor levels before finally igniting. I would have been throwing lit matches in there every 5 minutes to burn off little by little.

Typical to level the ground then place steel plates and pads for outriggers (stabilizing arms) to sit on with cranes, boom trucks, concrete pumpers, etc.
 
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  • #2,638
Unit 4 pics .
 

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  • #2,639
razzz said:
Nice grab on the pics AntonL. As far as the 'stop the leak' operation goes, just backed up the concrete truck and dumped the 'mud' into the access manhole as best they could. Didn't even use a concrete vibrator, probably the contaminated discharge was/is to 'hot' no one wanted to get splashed. Concrete truck driver never gets out of his truck, pours the mud while looking at his rear view mirrors, gets done and says, "C-ya." Laborer #1, "Boss says to vibrate the concrete." Laborer #2, "Fuk-u, you go over there and vibrate it."
:smile:you should take up writing movie scriptsBut tell me what sort of cabling jointing/dressing work is this? Normally cables are laid in cable trays and rise on cable ladders to which they are securely tied. Here we have a bunch of cables laid as I would expect in the wildest third world countries but not as part of the plant of a nuclear power station.
[URL]http://www.asahi.com/photonews/gallery/fukushimagenpatsu2/images/0402_plant1.jpg[/URL]
 
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  • #2,640
I came across a pretty good explanation of the Fukushima disaster by Murrray E. Miles.

http://atomicinsights.com/2011/04/fukushima-nuclear-accident-exceptional-summary-by-murray-e-miles.html

Would the members at Physics Forum please comment.

"UNIT 4 FUEL POOL

Fukushima Daiichi has one fuel pool for each reactor and a seventh common pool that has not been in trouble. They also have some older fuel stored in dry casks perhaps a quarter of a mile away from the plants. The unit 4 fuel pool is nearly full with around 200 tons of fuel in a water tank with a capacity of around 400,000 gallons.

You need to hear one more complication in the design. The fuel pool is really two pools separated by a gate. Fuel removed from the reactor goes first into the small, upper pool which is only 20 or 25 feet deep. Later they move the fuel to the big, deep pool. There was apparently only a little fuel in this upper pool at the time of the quake.

This UPPER pool broke. The three-eighths inch steel liner is cracked and will not hold water. The concrete wall in front of this upper pool fell off. Fuel was severely damaged probably by explosion. Temperature profiles measured by helicopters show clumps of hot stuff that must be fuel scattered around the floor area. This scenario is consistent with the numerous reports of fire in unit 4.

This is a real nightmare. But the main fuel pool in unit 4 appears intact and full of water. The spread of radioactivity came fortunately from a small amount of fuel."
 
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