Something Odd Is Happening at Reactor Number 4

George Washington's picture

NHK reports:

operator of the troubled Fukushima Daiichi nuclear power plant is
carefully monitoring the situation at the Number 4 spent fuel pool,
where the water temperature is rising despite increased injections of
cooling water.

Tokyo Electric Power Company, or TEPCO, says it
will inject 210 tons of water into the pool on Monday, after finding on
Sunday evening that the temperature in the pool had risen to 81
degrees Celsius.


On Friday, TEPCO found that the
pool's temperature had reached 91 degrees, so it began injecting 2 to 3
times the amount of water.


The Number 4 spent fuel pool stores 1,535 fuel rods, the most at the nuclear complex.

(Bear in mind that the amount of radioactive fuel at Fukushima dwarfs Chernobyl.)

As I noted on April 2nd:

Nuclear engineer Arnie Gundersen notes that the spent fuel rods in reactor number 4 have no water, and the rods are exposed:

In addition, the official Japanese atomic energy website shows 4,250 sieverts/hour of radiation inside the containment vessel at reactor 4 ("S/C" stands for suppression chamber):

These are very high levels of radiation. As I noted on April 10:

Radiation levels were apparently about 300 sieverts per hour ... right after Chernobyl exploded.

be clear, the Chernobyl figure is radiation released into the
environment, while the reactor 4 figure is radiation within the
containment vessel. I have seen no evidence to date that reactor 4 is

This is especially odd given that reactor 4 was supposedly shut down prior to the earthquake
for maintenance. In other words, reactor 4 was - according to
official reports - shut down, and shouldn't have very much radiation at
all. Something doesn't add up.

In contrast, the radiation inside the cores of the other reactors are much lower:

  • Reactor 1: 0
  • Reactor 5: 0
  • Reactor 6: 0

Indeed, the Japanese nuclear agency prominently displays the radiation data for all of the reactors except number 4 on it's main page. Number 4 is conspicuously absent, and you have to type in the url for the correct web page to find it.

The building housing reactor 4 doesn't seem to be quite as badly damaged as those housing other reactors:

However, a Fukushima engineer says he helped cover up a cracked containment vessel at reactor number 4 for decades.

the other hand, the fact that no radiation is being reported in the
drywell of reactor 4 (noted by "D/W" in the nuclear agency's tables) -
while there it is for several of the other reactors - might imply that
the containment vessel has maintained its stability.

this point, I don't have enough information to determine why the
radiation levels inside reactor 4 are so high compared to the other
reactors, let alone what it means. It might mean that reactor 4 is in
trouble. On the other hand, it could mean that reactor number 4 is the
only reactor which still has core integrity. In other words, maybe the
other reactor cores have much lower radioactive levels because most of
the radiation has already leaked out.

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gasmiinder's picture

Hey George - here's a link for you that has actual thoughtful analysis of the aftermath of one of your signature issues:



patb's picture

i think D/W is Drywell.  and S/C is Secondary Containment.

TerraHertz's picture

One more 'odd thing' among many. Not surprising considering the situation: an incredibly complicated 7-point giant nuclear/chemical/structural experiment, spawned by a cluster fuck of bureaucracy, earthquaqe, tsunami and aging nuclear plant, raised in chaos and denial, tutored by control freaks, lawyers and ignoramuses, and being dressed up for the ball by a bunch of overworked heros slowly dying of radiation sickness.

As for the reactor 4 S/C radiation figure, I notice one small detail about that form which may be significant, and MAY in some way explain the insanely high readings. Note along the top it says "D/W: _Sv/h S/C: 4250 Sv/h" then in the table the headings are "D/W  S/C" with no space to show units.

I think the form has been filled in incorrectly. I think the top line is meant to have an underscore before both instances of Sv, like so:

D/W: _Sv/H, S/C: _Sv/h

Clearly what is supposed to be filled in here are the symbols 'm' or 'u' (milli or micro) where the underscores are, to signify the units of the figures in the table columns below.

Instead, some twit has put the latest raw figure in the field at right. Thus this is yet another case of 'wrong units multiplier', that we've been seeing so often throughout this sorry debacle.

If so those raw numbers would really be 4250 mSv/h, or perhaps as low as 4250 uSv/h. Which would be more reasonable for the suppression chamber of a de-fueled reactor, that has become filled with contaminated water leaked from the wrecked and probably cracked SFP above.

A figure of 4250 Sv/h is absurd, even if the S/C was full of corium undergoing criticality. And note the reading has been fairly constant, which rules that out for multiple reasons. Not least of which is that if that much fissioning was going on in the basement, the entire building would be a bubbling pool of white hot glowing slag by now.

As for why no DryWell figures, the detectors may be either broken or cables damaged. Or perhaps since Unit 4 was shut down, the detectors there may have been removed for refurbishment?

patb's picture

why is the pool heating up?

patb's picture

why is the pool heating up?

Aristarchan's picture

I tend to agree with you. And, Tepco did report to the IAEA that rods had been removed from the vessel and inserted into the pools.

blindman's picture

the fuel rods from reactor one are in reactors
3 and 4, the rods from 3 are in 1 and 4, the
rods from 4 are in 1 and 3, and also on the ground and in the ocean. the rods from 2
are melting into the concrete below. ?
meaning the stuff blew up and is all over the place and the information is being managed
and controlled because the situation can't be,
is out of control and man will control something, that being whatever is left that he can control when he has lost all control.
something like this.?

Aristarchan's picture

Seems something is wrong with this data. Per outages, the Utility is required to report the movement of fuel from the reactor vessel to the spent pool, typically this is reported to the relevant Japanese agencies, and the IAEA. Per the readings, a Sievert is a human-dose-equivalent-scale, and no instrument I am aware of records over 500 Sieverts (per hour). The readings near the core after Chernobyl where right at 300 Sieverts (per hour). And, in those ranges, the source would most likely be medium energy neutrons.

The next issue is how can ANY radiation be detected in the torus connected to a reactor vessel devoid of fuel rods? Not possible unless it made it's way there by some destructive force on the pool, the concrete floors between the pool and the torus, and the torus itself. That to me is a reach. The only other thing I can think of is they might have transferred radioactive water from one of the other reactors into the torus on unit 4. If you are desperate for storage, and can accomplish the piping connections, then that might be a possible explanation.

But, that does not explain the numbers. 4000+ Sieverts does not make sense - at least not on an hourly basis...that number sounds suspiciously like a Roentgen number.

bingocat's picture

Given how little they have been able to get done at any level below ground level, I expect that arranging piping into the torus would be a stretch.

Personally, I am supposing it is possible that during all the shaking/soaking/electricity outages, at least one meter got itself dinged up a bit...

Aristarchan's picture

Well, they can get water into the torus through the recirc system or the main feedwater lines (backfeeding through the vessel and the downcomers), assuming they are intact.

Since radiation meters don't tend to read that high, I think the posting of the number, or the value attached is wrong.

patb's picture

is it possible Reactor 4 didn't have a hydrogen explosion in the fuel pools but rather a criticality event?


if it had exploded, why would that one side be pushed in?  If the explosion of Unit 3 pushed in that one side, how would it

trap hydrogen to explode outwards?


But say you have a critical flash?  Lots of Gamma, Beta, alpha X Rays come roaring out of the pool, and they hit the

concrete and effectively microwave it.  All the thin plate expands, cracks and because it is in sections bows itself outwards...

all the roof material heats up, cracks and frizzles into the fuel pits, covering the rods enough to stop the radiation coming upwards,  but the hot stuff, gains heat and burns its way south until it finally burns into the primary containment wet well.

that hot corium hits the wet well causing the steam clouds we saw a few days back and now that the water is cooked off

we see a big radiation spike, while it preps to burn it's way into the harbor.



Rusty Shorts's picture

 - notice the steel structure of Unit 4, looks as if it's drooping, sagging from extreme heat.. it's melting.

gasmiinder's picture

At this point, I don't have enough information to determine why the radiation levels inside reactor 4 are so high compared to the other reactors, let alone what it means. It might mean that reactor 4 is in trouble. On the other hand, it could mean that reactor number 4 is the only reactor which still has core integrity. In other words, maybe the other reactor cores have much lower radioactive levels because most of the radiation has already leaked out.

OR put another way "I don't know a damn thing but I can sound ominous and skim meaningless troll bait and happily conflate utterly different issues (released vs contained) to ramp up the eyeballs".

DeadFred's picture

Shhh!  GW serves a useful purpose even if he's a bit emo sometimes.

Pool Shark's picture

It's all just part of the Grand Unified Conspiracy Theory of Everything (GUCTOE):

You see...

The Bank of Japan had secretly hidden all its gold reserves in Fukushima Reactor #4, and this was discovered by Gert Frobe who hired Honor Blackman's Flying Circus to fly over the site spraying deadly Delta-9 nerve gas while Christopher Walken and Grace Jones planted a huge cowbell under the Eastern Pacific to trigger a massive earthquake and tsunami that would wipe out both the Japanese semi-conductor industry as well as Fukishima Reactor #4, which evil TEPCO had put into the neferious hands of Dr. No, who perished in the subsequent tsunami and explosions, which caused the BOJ's gold reserves to become radioactive and unuseable, even by Donald Pleasence and his cat, who subsequently fled the Island of Japan in a Space Shuttle piloted by Michael Lonsdale which later crashed in Egypt where he was joined by Richard Keil who tried to kill Roger Moore who was trying to recover the plans for the Egyptian revolution at Giza, but was thwarted by Barbara Bach who got to the plans first and transferred them to notorious Russian arms dealer Sean Bean, and working with media mogul Jonathan Price published false stories about the oil empire of Jimmy Dean who was trying to corner the cocoa market in Ivory Coast to produce a new, chocolate-flavored bacon, but instead resulted in a massive oil spill in the Mexican Gulf, ultimately causing a series of revolutions in the middleast as well as massive rises in oil, bacon, gold, and chocolate prices...


andybev01's picture

You totally left out Lazenby...

Mr. Mandelbrot's picture

 . . . and silver, but just about everything else was covered as far as I can tell.  

medicalstudent's picture

how are they coming to these measurements?


how far are the gamma dosimeters from the reactor core?


ambientgamma goes up by a facor of 1/r^2 as the dosimeter gets closer to the source.


maybe the dosimeter was dislodged?



majia's picture

I recall an earlier post by you recording rem exposure by pool and inside house. Is that correct? Have you kept records of exposure? I would be interested in reading what you've found...

sgorem's picture

" everybodies' gotta die sometime Red". platoon...........

etudiant's picture

The place is a lake of highly radioactive cooling water with some islands of busted and leaking reactors in it. With multiple earthquakes cracking and breaking everything,  that water will leak everywhere.

Nothing useful can be done until the lake is drained, maybe by year end. Of course, bad events could still happen, but not even an army of suicide volunteers could prevent them,

Fukushima will remain a running sore on Japans heartland, possibly for years.

johnnynaps's picture

This is a great time to be bullish on Sake. I'm headed out to purchase radiation free bottles now while they are still available.

Gold 36000's picture

Clearly there is something about the data that needs explaining.


Dejean Splicer's picture

These advanced nuclear topic should only be commented on by the likes of the ZH nuclear elite. Anyone else is simply not equipped to present an argument or suspicion about the topic.

So the deity himself does not have to bother I will include his reply here:

"Reactor Number 4 is fine. You inbred idiots should go fuck your mothers before you post topics about nuclear power".


Zero Govt's picture

yes ZH in-breds maybe but thing is Splicer, it's relative see the "nuclear elite" who you refer to as being "equipped" and qualified for an "argument" haven't diddly squat (a fuking clue) what they're doing.

Fukushitstorm is a graveyard of over-qualified nuclear expertise with not a brain bigger than a peanut amongst them (don't ignore the facts as they stand)

So we may be in-breds and fuk our Mothers, but that's nothing compared to the retards (that's "experts" to you) of Government. In a land of Govt retards the ZH in-breds are Kings (and perfectly qualified to comment).

Now go fuk yourself you snotty irradiated retard

Spastica Rex's picture

I think ZH should implement a feature where any posts on articles that have to do with:

  • oil
  • nukyooler energy
  • Israel
  • etc.

are automatically junked when posted.

I junked this one.

Dejean Splicer's picture

I spent the afternoon doing a little physical work and now I find myself sniffing my armpits as I read your post.


DeadFred's picture

Thank you for sharing that with us.

blunderdog's picture

"It's NUC-lee-er."  --Homer Simpson


Zero Govt's picture

send in another robot to Unit 4 to stare at it... that'll help!

maybe another Heli or fire engine to piss on it... that'll help some more!!

then the Japanese Prime Minister can write a new Recovery Plan... all well known Nuclear Industry 'solutions' and PR exercises while they haven't got a fuking clue what to do next



jtaskinen's picture

You should not be so paranoid, trust your goverment.

Everything is under control, you are perfectly safe.

They will tell you all you need to know.

HellFish's picture

Bad instrumentation maybe?

FeralSerf's picture

Yeah right -- just like all that bad instrumentation in Hondas and Toyotas.  If you can believe that the American military was so incompetent that it couldn't detect 4 highjacked planes on 9/11, then you shouldn't have any problem believing in bad Japanese nuclear power plant instrumentation that's probably tripley redundant.

If you don't like what the guage says or if the sheep might get agitated if they're told, lie about it.  It's an (often) tried and "true" official policy.  If we didn't like what the guage said, we'd usually beat on it.

fajensen's picture

If you can believe that the American military was so incompetent ...

Having worked with large American organisations, I can *easily* believe that not only is the military incompetent, it is way over-staffed, still adding bureaucracy at every level to increase the level of incompetence further, while outsourcing more and more to dilute any actual skills that might still linger! Its a damn process!!

Most bureucratic companies follow a cycle: They keep adding layers and layers of middle management until the organisation cannot carry it anymore; then they kick all layers from level 1-7 out and the cycle repeats. 

Generally, in such an organisation, you will find that, individually, most people are bright and motivated but that they don't care much about the organisation's goals because "their game" is somewhere else.

The government has no brakes on it other that default and the US military is The Most Sacred Cow Ever - so no brakes there either. Which is why the military is fighting ever more expensive wars against ever more insignificant opponents and not winning any of them. It is already bad when a bomb costs more than the target it destroys but it is pathetic when the logistics train delivering said bomb costs more manpower and money than the entire enemy force - and "we" still cannot beat the opponent.

This will get worse.

Ruffcut's picture

Maybe they are being confusing to further distract the bigger sucky picture.

Still waiting for better than expected.

fajensen's picture

I would not trust those exactly "0" readings either! "Sensor dead" would be my professional opinion.

sodbuster's picture

They need to bring in 4 carloads of Mexican workers(120 people). Call the cement trucks- 3 days those guys will have it encased in concrete, pay 'em in cash- problem solved.

Mr. Mandelbrot's picture

I think you're on to something . . .

dexter_morgan's picture

Is that an aged Earl Hickey in the photo with the eyes closed?

Commander Cody's picture

The Unit 4 reactor was defueled at the time of the earthquake and tsunami.  That is a fact.  All the fuel at Unit 4 is in the spent fuel pool.  As such, the supposed radiation reading in the suppression chamber (about 100 feet below and several concrete floors and walls away) does not make any sense at all.  The in-core radiation readings at the units with fuel in the reactor vessels does not make sense either (0?).  This information is suspect at best.

avonaltendorf's picture

Cody: That is a fact. 

Okay, I give up. How do you know it's a fact?

Commander Cody's picture

There are any number of sources including Mr. Gunderson, who states as much in the video above and who has not been cozy with the nuclear industry, that have maintained this.  Unit 4 was in a scheduled refueling and maintenance outage. This can be confirmed by viewing the photos of the damaged unit.  The bright yellow dome seen sitting on its stand on the refueling floor is the drywell (containment) closure head.  There aren't many facts bandied about on these comment threads but the fact that Unit 4 was in an outage is.  I don't think you'd believe reports from TEPCO and other industry-related organizations because I suspect you don't trust any of them.  Well, outages do occur, reactors are defueled during them and that is condition Unit 4 was in at the time of the tsunami.

disabledvet's picture

do you mean "the info from Arnie" or "the info from the government?"  this is why we all come to ZH.  the "question of the paranoid wackball" is seen in a different light vis a vis the simple question of "why is this happening in the first place?"  in other words "if the government starts from the premise that we need to lie from the get-go" then it makes everyone's job harder--MOST OF ALL THE GOVERNMENT'S ITSELF.  having witnessed it first hand however i must say i got great enjoyment in telling the entire postal inspection service "in my own way" that "you're being lied to by you own government."  i've heard that's a crime of course....

HK's picture

"if the government starts from the premise that we need to lie from the get-go"


Odd isn't it, that we actually need the best data possible to make the best decisions moving forward, whether as governments or individuals.

Commander Cody's picture

The data provided in the post is suspect.  I have thought from early on that TEPCO and the Japanese government have been downplaying the severity of damage to the facility.  Since world bodies and governments are apparently privy to the same information, they too are complicit. 

SparkyvonBellagio's picture

Means the Rods feel through to the pool, to the floor.

Or it had melted down Previously.



Commander Cody's picture

If the bottom of the Unit 4 spent fuel pool failed, then the readings might make some sense depending on how far contents have fallen.  Perhaps it is why the robots have not yet been in the Unit 4 reactor building.

gmrpeabody's picture

Are you implying, sir, that the Japanese use their rods to feel?