*NEW Dec. 1 Yomiuri* Gov’t Study: Reactor pressure vessel may be “tilted” after corium melted through concrete floor up to 200 cm deep

Published: November 30th, 2011 at 4:37 pm ET


Institute of Applied Energy: Corium Could Be 2 Meters Deep into Concrete, EX-SKF, Nov. 30, 2011:

TEPCO’s worst-case scenario (here and here) pales in comparison with the analysis by the Institute of Applied Energy, also presented on November 30 at the workshop held by the Nuclear and Industrial Safety Agency.

From what Yomiuri Shinbun reported (01:01AM JST 12/1/2011):

The analysis done by the Institute of Applied Energy commissioned by the national government, 85% of fuel dropped to the Containment Vessel in Reactor 1, and 70% of fuel dropped to the Containment Vessels in Reactors 2 and 3. The researchers at the Institute pointed out the possibility of the damage to the stainless-steel shroud that surrounds the fuel core, and of the corium having eaten away the concrete floor of the Containment Vessel up to 2 meters deep. Because of that, they also said it was possible that the RPV got tilted.

See EX-SKF commentary here

Published: November 30th, 2011 at 4:37 pm ET


Related Posts

  1. Report: If fuel melted through reactor, it would react with concrete floor of primary containment — Could add significantly to total radiation release May 23, 2011
  2. NHK: “This is a very severe accident” — Nuclear fuel at Reactor No. 1 may have melted through 65 cm of concrete… Only 37 cm at thinnest point (PHOTOS) November 30, 2011
  3. Study? No temperature readings for concrete floor — Outcome based on Tepco “projections” of decay heat & uses computer model from Westinghouse November 30, 2011
  4. Japan Nuclear Experts: Fears corium not totally covered in water at Reactor No. 1 — May only be 15 inches deep, even lower than No. 2 May 22, 2012
  5. Melted fuel in Reactor No. 3 appears to have burned through pressure vessel — Loaded with rods containing plutonium May 18, 2011

45 comments to *NEW Dec. 1 Yomiuri* Gov’t Study: Reactor pressure vessel may be “tilted” after corium melted through concrete floor up to 200 cm deep

  • farawayfan farawayfan

    I’m very pleased they’ve apparently started reading this website.

  • Gaffney

    So what situation are we now in, months has passed so has the corium cooled or has the outer shell of the corium been hardened? Is there still a chance it can fully melt out of the containment if it hasn’t already?

  • jackassrig

    So the heat has finally gotten to the support(s) that hold the reactor vertical. Holy Moly wait ’til that big SOB falls over. The structure under the supports must be sagging. I’m surprised the steel has manqaged to hang in this long.

  • jackassrig

    I got a q in there somehow.

  • moonshellblue moonshellblue

    Yes, the genie is out of the bottle, so to speak. I just wonder if the ongoing fission delays decay. Would the corium continue to be as hot as they were in March and would this delay any hopes of a cold shutdown? It seems to me it would but nuclear reactors are not my forte thus I’m sure I”m mistaken.

  • These same questiments came out about about 2 months ago !

    About 2 to 3 meters !

  • Grampybone Grampybone

    If the cores are at 2 meters into the ground then what kinds of chemicals can we expect to see released from this? There has to be a damage analysis done of the steel supports to see if they can be reinforced. The deepness of the cores is very concerning to me. The data they have just released is an estimate because TEPCO cannot determine anything. It would be nice to know just how they confirmed the core is 2 meters deep rather than 4 or 8. At least the press got around to saying something.

    • Grampybone,
      They must be using heat detecting sensors to locate them, if not it’s all guess work !

      I have to think they would be putting boron on them if they could get it the but if mud and sediments have settled over them into the decent the Boron could not get to the curiums to do any good !

      They will put out all the isotopes that they are designed to do !

      • I stated 13 feet in August.

        I suppose it was a just another good theory.

        In my opinion, It is steaming constantly just above the bedrock. Slow breathing, seeping roughly 3-5 inches a week.

        The granite layer above the bedrock is probably holding the main masse, above bedrock. This is a short cake walk for the fuel in the event cooling operations are halted due to obstacles implicating the operation. We have to acknowledge tepco is top feeding the RPV< As the coolant needs to follow the same path as the fuel directly in order to keep the corium from achieving fission. In my opinion the fuel is only being moderated by boron at a rate of 80 out of 100% on its atomic reactions. So there is always fission taking place although the decay of the fuel is taking place 100% of the time. Only a slight amount of the fuel is considered hot (20%). So this would indicate the decline in depth. Is attributed to the fuel breathing. As many of us already knew. The fuel is in a state of inconstant criticality. Hence why the reactors are convecting on and off as they have been since april. So in better words. The fuel is inching its way towards no tomorrow.

        • No tomorrow meaning no tomorrow quite literally im afraid.

        • Tacomagroove,
          I think what ever boron got to it has long since been working to quite the monster, I really think as it borrows its way through the earth debris above settles over from water mud and everything up stairs that can flow with water and fills the hole behind it turning to a clay like hardened from the heat of the beast so the temperatures began to rise and eat through became faster through the earth exponentially as the heat grew, a time line will be hard to calculate as to the relevance of what is below to burn through but we all will know when it finds the H2O for many will feel the ground shutter and move, laying in bed or in our chairs !

          At that time we all will know we are in the final trough’s as the process of melt through continues if there is no spontaneous nuclear reaction it will begin to burn through again into the earth after it has evacuated everything above it preparing a new path, and a new wait ….
          but we agree … BOOM !

  • ion jean ion jean

    And these numbers are reinforcing what Arnie Gundersen has been saying about the flaw in the reactor design which shows that 30 plus reactors in the US have no better meltdown containment than the colander I just drained my pasta with

  • Elenin Velikovsky Elenin Velikovsky

    Grampy, Doc,
    The Ground Penetrating Radar ought to be able to
    find the dern hot thang…
    It might have travelled enough to need a shot of three-dee
    seismic shock-reflection-location….
    Common enough technology these days, but The Lies must be Managed.
    There is a Level of Alchemical Awareness which
    is Withheld from Us, because we have shown little Goodness,
    We don’t deserve to project our Violent, Ignant Ways upon the Universe.
    The Annunaki are coming.
    “To Serve Man”….
    It’s a

    • Well we orta be brown and toasty when the get here !

    • Bobby1

      Strontium and plutonium are like salt and pepper to these cosmic gourmets. Human flesh seasoned to perfection.

      • Pretty Morbid for you Bobby1

        Is it time to go to South America yet?

        • Bobby1

          Maybe it is, dunno. I’ve been saying all along that people shouldn’t be taking potassium iodide, they should take kelp and seaweed. Potassium iodide should be for emergencies only.

          I just picked up some Lugol’s solution with potassium iodide.

          • Is it time to take it now?

            • Bobby1

              Well, after seeing those astronomical beta readings, and considering that I feel like I have a golf ball in my throat, yes.

              You should consider that I am hypersensitive to toxic metals, though. If everyone was like me, there would have been a revolution months ago.

              • Many people I am talking to have low level symptoms that could be viral or could be radiation, including my 10 year old son (and me).

                No typical signs of illness. Instead, people’s throats feel scratchy, people feel run down, and many people have problems with headaches.

                Yet, with all these symptoms people are not having excess mucus or sinus congestion…

                Holy Cow–These are the symptoms of low level exposure. What else?

                Are we now at visible symptoms?
                Are new highs testing bodies now carrying radiological burdens?

                • Bobby1

                  Yablokov on Chernobyl:

                  Endocrine dysfunction, particularly thyroid disease, is far more common than might be expected, with some 1,000 cases of thyroid dysfunction for every case of thyroid cancer, a marked increase
                  after the catastrophe.

                  • NoNukes NoNukes

                    Sorry that you are sick, Bobby1 and Majia. Friends in the SF Bay area are starting to get sudden gastrointestinal pain (I have an ulcer) and seizures for the first time in their lives.

  • jackassrig

    I want to know what kind of supports are under the reactor. Is legs, lugs, or skirt. If they put this reactor on legs in an earthquake zone, they should all be rounded up and hung. Nobody in their right mind would support a vessel of this size on legs. I see on the sketches legs but of course these are just sketches.

    • You seem to know engineering jakassing.

      Did you see the early pictures of the reactors?

      There seemed to be quite a bit of evidence that two of the three reactors were destroyed utterly.

      I think we are beyond pedestals.

      Also, did you see the infrared image of unit 1 recently posted at Fukushima Diary?

      Red hot core dispersed…

  • Grampybone Grampybone

    After a magnitude 9 earthquake followed by a 30ft wave I am amazed that the plant even remains on the coast. Even if they put lugs on the base of the reactor I doubt it hold to that level of shaking. The steel at the bottom of the containment must have taken some serious damage.

  • evendine

    Here’s a paper on simulated corium erosion of concrete (using thermite in place of corium) The thermite reaction is much cooler than corium (around 2000 degC instead of 5000 degC, but it still erodes the concrete at 4cm per minute!

    Typically for Tepco, the figures they’ve given are almost certainly rubbish. According to this study, 7.6m of concrete would last just over 3 hours!


    • evendine

      :0)) No need to hurry – we’ll all be mutant folk soon ;0)

      I posted the paper to give some idea how fast the corium might penetrate the concrete – clearly very different to the Tepco story. Could well be that things will be different once the strata below are reached and the corium will tend to cool, slowing the rate or erosion over time, even in concrete, apparently.

      The real danger is that the corium will meet a body of water which will flash into steam creating a shockwave sufficient to compress the corium into a geometry which causes prompt criticality for an instant. I think the explosions at 3 and 4 may be examples of this kind of event (in SFPs), but were confined for a very short time by the hydrogen explosion shockwave.

      In the melt-out scenario, since the corium is confined beneath the building and the ‘wormhole’ is being backfilled by crusts formed during the melting process, the containment and therefore yield could be much higher and the resulting explosion might conceivably throw the whole site into the stratosphere :0(

      This article summarises the possibilities:

      • evendine,
        We here have disused this scenario for seven months or more and we agree with your assessment as it always has been been mine and other enenewer’s too as to how the events will go and why ! (Right down to backfill)

        • evendine

          xdrfox: Yep – have been following events through enenews / ex-skf from the beginning – it’s a relief to have a place to keep track of the real situation and exchange views…

          Surely something can be done to locate the cores and some sort of remedial action be taken? I guess Tepco are more interested in propping up their share-price, while they quietly strip the company’s assets, than avoiding a cataclysm unfortunately :0(

  • datura17

    to find the corium, couldnt a person just take a horizontal boring machine and put a temperature sensor on it and do multiple probes?

  • maaa

    If the corium gets to the lava, it will flow to the rest of the world. Any volcanic eruption will release deadly radioactive caesium, plutonium.

    • maaa, Radiated from within as well !

      Back to the outside world where it has been and continues !

      Our whole planet contaminated forever !

    • BeniJax

      Seriously maaa? The best thing with the corium might be for it to burn quickly to the mantle (lava) where it can’t contaminate us any more. By the way, Earth is warm on the inside from radioactive decay, corium go home and call it a day.

  • 8thandLamar 8thandLamar

    I sooooo hate it when my pessimistic instincts (and over-educated brains) are right. Sometime before 3/11, I noticed an article clarifying the “digging to China” meme (from USA)….It said it was more accurately “digging to China from Chile”. I thought that was cute. http://en.wikipedia.org/wiki/File:Antipodes_equirectangular.svg
    When the Chilean Puyehue volcano blew (and covered the southern hemisphere in ash) in early June, I got a really BIG sinking feeling in my gut… The pictures were massively more spectacular, the clouds looking more ominously mushroom-like, than usual. (I had been painfully dragging my Lymes-addled mind towards the steps I’d have to make to move to Argentina. I had always wanted to settle there!)
    Since then, although my mind and health continues to clear, I’ve been strangely frozen in place( N. Cali )….getting nothing done but the work of safely eating, sleeping, breathing, and reading (thank you enenews!) I’m thinking that the only thing left to do is to implore ANY and ALL “supernatural” entities that need begging (our permission) to get us the hell out of here or, shooot, just fix the whole frickin’ mess.
    Damn, just when I was starting to feel better… Once again…THANK YOU everyone at enenews. It’s been nice to have pleasant and caring company.

  • Elenin Velikovsky Elenin Velikovsky

    Hey y’all,
    Notice how there was a rumor, way back months ago,
    of special US Marine (?)
    outfit tunneling way under, ala Chernobyl attack,
    to somehow “Catch” the blobs with some kind of hardened vessel?
    …possibly to Remove the mass somewhere?
    wonder if there are any expose’ stories following that?
    Of course it would be suicide for these men involved….