Gundersen: Top lifted off Reactor No. 1 containment BEFORE explosion? (VIDEO)

Published: February 9th, 2012 at 2:59 pm ET


Title: New Containment Flaw Identified in the BWR Mark 1
Source: Fairewinds Associates
Speaker: Nuclear expert Arnie Gundersen
Date: Feb. 6, 2012
Emphasis Added

Transcript Excerpts

[…] I wanted to focus on what happened after the tsunami but before the explosions. […]

Well at 2 in the morning, the pressure inside the containment [at Reactor No. 1] was almost 9 times higher, that means it was about 125 pounds per square inch. This containment was not designed for 125 pounds per square inch. To look a little further though, by 9:30 in the morning the pressure starts to drop and for the next 7 hours the pressure is much lower than it was at 2 in the morning. So the question is, how could it be that the pressure in the afternoon was lower than the pressure in the early morning? Remember, there is a violent chemical reaction going on inside the nuclear reactor where all sorts of hydrogen gas is being generated.

One possible reason for the lower containment pressure is that the containment vent was open. But that had not happened yet. So what made the pressure drop down? One possibility I believe to be the case, is something that happened 40 years ago at a plant called the Brunswick Plant in North Carolina. Now the nuclear industry in the U.S., the IAEA, the Japanese, are all aware of this, but they are all ignoring this test and pretending that it did not happen.

What happened 40 years ago was this: When a containment was pressurized, it was pressurized to just about 100 pounds [per square inch] and then something really strange and unexpected happened. The top, the head of the containment, began to lift off of the bottom of the containment. […]

Let’s look at that table again from Fukushima. Where did Fukushima settle out at? Just about 100 pounds per square inch. What that tells me is that the head of the containment lifted up and gasses began to sneak out into the reactor building, which is that box that surrounds it, well before the containment vent was even opened.

[…] It seems to me that for 8 hours or more, the containment at Fukushima was basically ruptured, that the top had popped up, and gasses were sliding out, so that it could not go over 100 pounds per square inch.

And hydrogen gasses were leaking out of the containment and into the reactor building for a long period of time. After that, it only took a spark to blow the reactor building up. This is a really important distinction. The nuclear industry, the Nuclear Regulatory Commission and the Japanese are saying that we can make the vent stronger so that this accident cannot happen. But if the nuclear head is lifting up, the vent is irrelevant. […]

Read the full transcript here

h/t Anonymous tip

Published: February 9th, 2012 at 2:59 pm ET


Related Posts

  1. Gundersen: Unit 3 explosion “very similar” to what happened at Chernobyl — Pieces of nuclear fuel found offsite indicate fuel racks were lifted up (VIDEO) August 4, 2012
  2. Gov’t Nuke Experts: Top part of Reactor 1 containment may have opened up before first Fukushima explosion October 17, 2012
  3. Nuclear Engineer: New footage shows Reactor 1 has “ruptured” containment structure, most likely from the explosion — Water to cool “what’s left of core” flowing into environment (VIDEO) November 15, 2013
  4. Gundersen: The containment vessel exploded at Fukushima Reactor 2 — “There’s definitely a large crack” (AUDIO) March 11, 2013
  5. Gundersen: Image shows radioactive “thermal flare” was coming from Fukushima Reactor 3 — “Exactly where the containment should be” (VIDEO) March 25, 2013

107 comments to Gundersen: Top lifted off Reactor No. 1 containment BEFORE explosion? (VIDEO)

  • Dr. McCoy

    This insane industry must be stopped.

  • Kevin Kevin

    Dump the big six its time to move on!

    short vid, must watch, great fun!

  • Ganxet Ganxet

    yes , i’m with u DR. McCoy, but hoW?
    this is the question.
    Maybe we should turn off the lights?
    Try to buy green products?
    Less comsumption devices?

    small things could make great things

    • Dr. Anne Lee Tomlinson Maziar anne

      Are you saying that mankind doesn’t have the brains to figure out how to stay alive, that we can only kill ourselves off completely as a species because nuclear is the only answer?

  • gottagetoffthegrid

    for a sense of scale here is a link to an old photo of one of the Browns Ferry containment vessels (CV) during construction. the Reactor Pressure Vessel (RPV) sits inside this thing. you can also see the torus called the suppression chamber around the perimeter.

    note the little man sitting on top left of the “inverted light bulb” CV.

    now, the lid that Arnie is talking about is in the foreground at the bottom of the pic waiting to be hiosted up top.

  • Bones Bones

    Arnie really knows how to break things down and explain them. So after the hydrogen explosion in the reactor building, does the head of the reactor blow off?

    • Room101 Room101

      I love him, too–but almost a year after the explosions? Ugh.

      • Kevin Kevin

        Good point.

        Why now? And since admin has posted that the explosion was related to the earthquake damage and people as high up Jazcko were aware of this on MARCH 12th I think it imperative Arnie address these outstanding concerns.

      • moonshellblue moonshellblue

        It takes time to analysis TEPCO’s numbers which are questionable in some cases and this is important as these BWR are all over the planet and this is a very serious flaw. At least Arnie is trying to make sense of what has happened and if the NRC would heed his warnings perhaps he could prevent such a disaster from happening again. IMHO

        • Kevin Kevin


          I agree and this is why I encourage Arnie to continue doing the work he has done. In this instance the “vent” issue is something Arnie has long advocated. He has underscored the risk the Vent fix proposes all along.

          What he has not done in the instance of Reactor one and in his most recent video is explain how the EQ damage led to a radiation leak and subsequent explosion. Rather he has taken the entire focus off that and placed it on the theory he outlines in the video which he opens by saying ” Lets focus on the time after the tsunami to the explosion.” In doing so he sidesteps the evidence that has been presented that shows the damage required to ignite the meltdown stems from the EQ.

          This too has ramifications that are very serious and the idea is to learn as much as we can about it in order to prevent such a disaster from happening again, exactly as you say.

    • TerraHertz TerraHertz

      Thanks to Arnie for the great work!
      I only wish he’d bear in mind that many people are a. not engineers, and b. not very terribly good at visualizing mechanics. He should explain a bit more precisely (though the illustration was pretty dammed clear)

      When he says the lid ‘lifted up’ he means by a tiny amount. Just enough to open the seal around the edge. About the same the head of a car engine ‘lifts up’ when you blow a head gasket, ie hardly at all. Makes no difference though, the seal is busted and stuff is leaking out. With the ‘stuff’ in this case being a brew of hydrogen, steam, and other corrosive gasses and liquids at over 100PSI and over 100 deg C, it’s very likely there’d be rapid erosion of the metal at the leak. Meaning the leak would get bigger, fast, and not reseal once the pressure dropped.

      The other point he might have made, is that the lids on reactors 1, 2 and 3 are almost certainly still in place, just probably leaky. And also irrelevant, since the reactor contents are likely melted out through the bottoms of the vessels.
      Plus, there’s no way anyone will be seeing the lids for a long time, since they are underneath huge concrete shield ‘plugs’, and the gantry cranes are wrecked. Construction cranes typically can’t lift such weights.

      Number 4’s lid was removed at the time; there are pictures of it sitting on the floor of the crane room, over to the side among the rubble. In at least one of those pictures you can see the retaining bolts clearly, since the bolts were just sitting loosely in the flange holes, and the explosion and rubble fall knocked many of them upwards and crooked.

  • Kevin Kevin

    Interesting information Uncle Arnie puts forward here.

    First off, would it not apply across the board? Not just reacor one?

    Second it puts alot of the “official story” in deeper question and really slams the industry for not including data they had known from previous tests.

    Third, the picture Arnie provides showing the containment vent working because of the steam/smoke at the top of the stack also indicates that the same was occuring two reactors over, presumably number three. IT may be a could but it certainly looks like more steam was coming from that stack.

    • bmurr bmurr

      Different fuel cycle timing will play a huge roll in decay heat for each reactor. Look at unit 3, big difference. Lots of factors here, but the numbers he uses provide the evidence to support his idea. So it isnt like every bwr 1 will do this in an accident, but every bwr 1 under these conditions will result in the lid lifting.

      • Kevin Kevin

        Well fair enough I am no expert. However I cannot see how the same dynamics do not apply to each of these exact same reactors with similar circumstances.

        Also, Arnie focuses on the time between the Tsunami and the explosion. He does so in order to prove that all BWR’s are at risK as the testing indicated and the accident may have confirmed. Yet he has not comment on the time between the earthquake and the tsunami, where it has been shown that serious damage occurred to the containment and radiation leaked BEFORE the tsunami impacted the plants. This too is very important and also impacts all BWR plant as proven in this tragey. A very important piece of information and one I would like to see Arnie address.

  • bmurr bmurr

    And now we know why unit 1 needed a tent built around it. They are fully aware of this and keeping it under wraps

  • Ganxet Ganxet

    i think all reacors need it.

  • Heart of the Rose Heart of the Rose

    How much sooner? ..seconds?..less.?
    What is the point here?
    And then the mushroom cloud….

  • maax maax

    “But if the nuclear head is lifting up, the vent is irrelevant”

    why? I don’t understand that.. could someone explain me?

    • Picture a kitchen pressure cooker. There is a weighted stem vent on top of the lid, but if you take the lid off, the vent is meaningless as far as pressure is concerned.

      • maax maax

        But the vent on the pressure vessel isn’t on the top of the nuclear head, is it?

        • Kevin Kevin

          no, down low on the side.

          Another point Arnie makes and has made in the past that is valid.

          One it was originally desinged with no vent.

          They learned that the cap is not very good really. So the fix was a vent! Unbeleivable really. But I guess they felt it gave them some control on pressure and in an emergency releasing some is better than blowing it all.

          Still an absolutely irresponsible and icompetent move and one that also underscores the approach this industry consistently takes. One where risk is mitigated to a point and redundancies are built in but all the while there are points, almost inevitable points, that nothing can be done and harm will result.

          Unnaceptable but true.

          • maax maax

            Thank you Kevin.

            The use of a vent is indeed an unacceptable makeshift fix. It shows that the risks are not well controlled and anticipated from the beginning. Other defects of this type of reactor have been pointed out, like the control rods coming from the bottom, the pressure suppression containment schemes, the pool situated on the top of the reactors, etc… and we keep saying that the life of these facilities can be prolonged more decades…

            But well.. I still don’t understand technically why the vent is irrelevant, if the nuclear head is lifting up. Is it because of a pressure issue, or because the release of radioactive materials would prevent a worker to approach the reactor and open the vent?

            • Kevin Kevin

              I am not sure the context.

              Who said the vent is irrelevant and why? Irrelevant with respect to what?

              In this instance the vents have been used by the official story as part of the problem if not the centre of the problem. They operate automatically. It was said that is what caused at least one of the explosions, the automatic opening of the event releasing hydrogen into the secondary containment at such rates an explosion was virtually inevitable and humans could not close them due to failed power or some other reason I cant recall of the top of my head.

              The vents are there becuase the test proved the lids do not contain the pressure after about 100 psi |(which people are pointing out seems low). When pressure gets to those dangerous levels the vents, lower down and on the side are to be opened to release pressure and maintain the integrity of the primary containment.

              • maax maax

                “Who said the vent is irrelevant and why? Irrelevant with respect to what?”

                > it is said at the end of the video. Look at the end of the text here:


                “The nuclear industry, the Nuclear Regulatory Commission and the Japanese are saying that we can make the vent stronger so that this accident cannot happen. But if the nuclear head is lifting up, the vent is irrelevant. The containment on the Mark I design has a design flaw that the containment vent cannot solve.”

                • Soyogu

                  The nuclear industry, the Nuclear Regulatory Commission and the Japanese are sayimg this while turning blind eye to the fact (at least I think Gundersen is right) that the cap lifted. They say the hydrogen got out of the container because the vent was leaking, not the cap.

      • jec jec

        Pressure cooker lid–good concept. Everyone who cooks is afraid of a pressure cooker blowing up. Picture a kitchen-ceiling walls windows all covered with hot boiling liquid. And thats with only 15LB pressure. If the pressure weight/jiggler is removed..a hot scalding column of steam/juice sprays out to the ceiling in plume. HOT HOT HOT.

  • dear jones

    Lucky to the Nuclear industry. This fail become the Safety Design to prevent the total blow up of the Containment Vessels.

  • jackassrig

    Where are they getting 125 psi. These reactors operate about 1000 psi. You could operate a water heater at 125 psi.

    • These are not PWRs, they’re BWRs. The containments (either BWR or PWR aren’t designed for that kind of pressure regardless, and the head gaskets on the smaller BWR containments have been known to fail in the past during pressure testing. The bolts are occasionally not torqued properly either.

      This is an issue with the containments, not the reactor vessels. Though obviously the reactor vessel in this case wasn’t holding pressure. That’s how the containment got pressurized.

      • Kevin Kevin

        Amazing however that the lids lift!

        I cannot imagine the pressure involved to do that. 125 PSI sounds low to me to “stretch” the bolts as Arnie described it. I mean there has got to be a hundred of those real huge thick bolts holding that cap down!

        This stuff is just insance.

        And if they tested with normal oxygen 40 years ago and found this flaw how in the hell did they get to go ahead without addressing this? Its seems insane! Its a primary containtment, its entire purpose is to contain! Then the fix is to put a vent in a primary containment! Thats like fixing your bucket by putting a hole in it! And using chewing gum when required.

        This stuff never ceases to amaze me.

        • Spectrometising

          I agree Kevin.
          Even though Arnie may be right and so on, 100Psi seems very low to me also.
          Maybe i am missing something??
          Hmm..i need to check this out further

          • Spectrometising

            On a diesel engine, the bolts often need to be re-tightened as they stretch. On other engines the head bolts are pre-stretched/tensioned. After the engine is run for a certain time, they are re-torqued to prevent a head gasket blowing out.
            Maybe it has something to do with thermal expansion?
            I am puzzled, and like i said i will check it out further.

            • Kevin Kevin

              To be clear.

              I find the 125PSI thing to be odd.

              I believe Arnie when he says there was a test and this happened, maybe at a different pressure rate.

              Regardless, my major point is that while Arnie’s theory is plausible, what is also evident is that the damage was caused by the earthquake, radiation leaked before the Tsunami, the NRC was aware of this.

              There are to many anomolies, and Arnie does not at all address them and instead focuses elsewhere. I think that earthquake damage leading to meltdown is pretty much a showstopper for the industry and Arnie should address these concerns as they conflict with this theory and there is evidence they occurred.

              • lokay5 lokay5

                “the damage was caused by the earthquake, radiation leaked before the Tsunami, the NRC was aware of this.”

                “earthquake damage leading to meltdown is pretty much a showstopper for the industry and Arnie should address these concerns as they conflict with this theory and there is evidence they occurred.”


                • Kevin Kevin


                  I am glad you see how important this is.

                  Arnie’s video, while informative, has built into it a glaring conflict as outlined briefly in my quotes you referred to.


              • jdotg

                Didnt arnies data say containment pressure was increasing to a point? To me that is suggesting it held right? Until overpressurized and it blew its lid decreasing pressure. Idk. If the earthquake compromised containment im not sure id hold the pressure to begin with

                • Kevin Kevin

                  Its a good point you raise.

                  However based on the design it seems there is a possibility, from my laymans perspective, which is why I continually say Arnie must address this.

                  I think its very important.

        • kimyo

          >I mean there has got to be a hundred of those real huge thick bolts holding that cap down!

          you didn’t read the transcript. there is no dispute here, the lid did lift away from the test reactor 40 years ago. the size of the bolts is of no consequence.

          this is the relevant portion:
          “What happened 40 years ago was this: When a containment was pressurized, it was pressurized to just about 100 pounds [per square inch] and then something really strange and unexpected happened. The top, the head of the containment, began to lift off of the bottom of the containment.”

          please stop impugning gunderson’s ‘integrity’. he has never stated anything that he can’t back up. either show us an error on his part, or, name me anyone else who has been more accurate and precise.

          • Kevin Kevin

            No Kimyo,

            You did not read the point I was making.

            I did say that I believe Arnie and the test of 40 years ago. What I question on this small point is.

            1) 125 PSI makes no sense. When you look at that cap, it is pretty serious and for me it does not add up, but I dont know he is the engineer I am not

            2) If 40 years ago we learned of this and did nothing but install a vent, that is a serious issue.

            Finally what I am suggesting, no demanding, Arnie address is the notion that damage was caused by the earthquake, subsequently resulting in both radiation release and the explosion. I have outlined this clearly in other posts and the admin here has posted substantial evidence backing up this claim, of which more can be provided if you require.

            To be absolutely clear, this is what needs to be addressed not the cap, alhtough I would like to learn more about the pressure issue, but that is not the main concern. The main concern is that considerable evidence exists and has existed for a long time that directly conflicts with Arnies most recent video and he sidesteps the issues in favour of the theory he presented. He needs to address that in my opinion. Period.

            • lokay5 lokay5

              Kevin, 125 PSI is a fractiion of the operating pressure of a PWR. PWRs operate at 2250 PSI. The lid lifted at 125 PSI?

              • kimyo

                do you have a link on the 2250psi number? i could see that number for the steam tubing.

                this is from gunderson’s transcript, saying the ‘normal’ pressure in the fukushima reactor is 14.5psi:

                “The bottom of the table is right before the accident and the pressure was atmospheric. What that means, .1 is normal pressure, 14.5 pounds per square inch”

                • jdotg


                  That’s great and all, that a PRESSURIZED water reactor, holds 2250 psi, as it should. The pressure keeps the water liquid. That’s the whole design basis, which they are designed and named after.

                  Unfortunately, there are no PWRs at Fukushima 1 or 2. So sorry, this is completely irrelevant.

                  The RPV, notice the letter P standing for pressure, in a BWR, is designed to hold the pressure in this type of system. Not the containment, which houses the RPV.

              • Kevin Kevin

                Well, that has been the question I and a few others have raised in this thread.

                Arnie makes the claim. Which does not add up. But honestly if anything I am sure it is just a mistake either with Arnie or our interpretation of what he is saying. The point is they tested it and the lid lifted at what exact pressure is not clear but according to Arnies video 125 PSI is the claim.

                Regardless of the issue of pressure. It is unnacceptable that testing 40 years ago found this flaw and subsequently no changes in design were implemented but rather the vent was installed in a (all?) of these reactors. It was a fix, and that fix is also at the centre of this controversy.

                However that is not my primary concern. My concern as I have repeatedly stated is the evidence that earthquake damage resulted in the release of the radiation before the tsunami. Which would impact Arnies hypothesis and it is stunning that he has consistenly over looked this fact when presenting these issues and too present an alternate theory without addressing this evidence is startling in my opinion.

                • Kevin Kevin

                  Also Lokay.

                  A PWR is a Pressurized water reactor.

                  What we are dealing with is a BWR. Boiling water reactor, presumably less pressure is involved.

                  However that they are able to contain a PWR at those rates, why such a poor cap with such a low threshold on a BWR?

                • lokay5 lokay5

                  BWR operating pressure is 1000-1100 PSI

                • Soyogu

                  Kevin, for this and all your other posts on the matter of the accuracy of the theory, they are good points but you (or any of us) aren’t likely to get proper answer without sending them to Gundersen himself. Have you?

              • PWRs operate at ~2300 psig. That’s the pressure inside the containment vessel, so the water can be “superheated” to more than 300º and not boil. Makes for better steam production inside the steam generator. Where the feedwater – the water being turned to steam – is held to a much lower pressure so it CAN be turned to steam. A BWR operates at about 1,000 psig.

                Reactor vessels are big things, made from 5-10″ thick steel. To grok the entirely different situation with containments, consider that they are much bigger than reactor vessels and are lined with thinner steel. By way of imagining pressure differential, consider that a PWR containment (that big dome that covers the reactor, the steam generators and all associated equipment) is kept at a negative 3 psig (where gage is normal atmospheric pressure). Workers must go through an airlock to get in and out. ~3 psig is about the same pressure differential between the inside of an airliner at 30,000+ feet. What happens when somebody puts a bullet hole in the fuselage at that differential (or a window blows out)? Not pretty. One hydrogen explosion of containment atmosphere at TMI-3 pegged the pressure gage at 32 psig – more than twice its design basis. It miraculously held, though the main equipment hatch was warped so badly it had to be cut through with torches when entry was finally allowed.

                A 12″ equipment hatch blew in the airlock once at that differential (3 psig). It sucked a man right through the opening and ‘flew’ him all the way to the reactor at the center of the containment. He laid there for hours because the containment had to be brought to atmospheric before anybody could enter.

                So no, a 100 psig differential causing the head gasket/bolts to fail is not the least bit ‘unbelievable’.

            • kimyo

              >When you look at that cap, it is pretty serious and for me it does not add up

              again, there is no doubt here. that cap, as installed on reactors all over the world, will lift. what it looks like, how beefy it is, is immaterial. simple truth: the cap has been demonstrated to lift at 125psi.

              it only needs to lift ever so slightly to allow gas to escape.

              • Kevin Kevin

                No argument from me on thispoint as I stated repeatedly elsewhere. It is just remarkable that

                1) the design was not corrected
                2) that huge lid with all those bolts would lift like that under what seems to be fairly low pressure rates.
                3) that the fix was a venting system that is now at the heart of the problem.

                • jdotg

                  Well as in all cases with pressure, in order to combat it, you’d have to relieve the pressure in some way. The most logical in my mind would be a vent, which allows the pressure to escape in an alternate route.

                • jdotg

                  It is troubling though that they were aware and did nothing. But then again, is that really all that surprising given this industry’s track record?

        • It’s not amazing to me, having actually seen what can happen in huge spaces with pressure differentials down in mere single digits. BWRs are designed to vent pressures in a couple of ways. For pressure spikes associated with sudden scrams, there’s the torus – a.k.a. “pressure suppression pool.” For pressure spikes inside the containments (usually associated with use of the torus) there are the vents to the vent stack. Primarily for gases rather than water (which will be in the torus). Those vents need electricity in order to operate. At Fukushima, there was no electricity.

          I know that 125 psig doesn’t “sound like” a lot. In reality it’s tremendous – enough to bend, stretch and occasionally even phase-trans high grade steel. Such as might be used in things like head bolts, for instance… §;o)

    • Spectrometising

      Yeah i aggree jackassrig
      February 9, 2012 at 5:41 pm
      Has me stumped!!

  • Anthony Anthony


  • It make perfect sence !

    • Kevin Kevin

      Until you see the post that says earthquake damage caused the explosion that admin has subsequently posted!

      • Soyogu

        Title: Hydrogen leak leading to Fukushima Unit 1 explosion caused by earthquake impact
        Source: Enformable
        By: Nuclear Regulatory Commission
        Date: March 12, 2011

        Yes, “Nuclear Regulatory Commission”. Can we trust them? It sounds like information that would save them after what Gundersen came up with. They should have done more than just order a vent, right?

        Personally, I think it could well be both the problem in structure and damage from the quake at the same time.

        • I seem to recall they retrofitted the vents a few years ago because the originals didn’t work well enough to pass muster. Unfortunately, the new ones don’t either (and retrofits to the retrofits are a hot debate item at NRC right now). Also, they need electrical power to operate. There was no power at Fukushima once the tsunami came through, apparently workers did try to operate some vents manually but rad levels were too high to pull that off. So basically all of what got vented from the containments was vented through the heads of the reactors. Which are known to leak at DB pressure, which is less than 100 psig.

  • retali8 retali8

    i guess this is all part of a plan, within the nuke industry to take some pressure off tepco and japan coming up to the 1 year anniversary, therefore it will take a little significance off the whole event and cause alot to overlook it… remember they MSM want to keep the silence, sadly, the children dieing should wake the sheeple,, how long will it take before they arent shunned and silenced?

  • bcguy

    Thank you very much Arnie. You always make it clear. My question is this. If this happened back in the first day… what about now? Does this mean that the vessel is getting hot, steaming and wanting to blow the lid off? Now I’m wondering… will these reactors currently venting radioactive steam from the lids? If so, it’s much like Chernobyl in the sense that it’s only a matter of time when the lid(s) come off, right and expose everything. But not one reactor, but 2, 3, 4, 5 reactors…

    • The containments of units 1, 2 and 3 are all breached. That means they aren’t holding any pressure, and haven’t been since the first days of the melt-throughs. Caps or no caps makes no difference.

  • Dr. Anne Lee Tomlinson Maziar anne

    Nuckelchen posted these photos of reactor #1 that I had never seen before. A whole side is ripped out:
    February 9, 2012 at 6:05 pm ·

    a google earth view from the webcam standing streaming area:

    and a west/above side view:

      • Dr. Anne Lee Tomlinson Maziar anne

        After copying this photo onto my computer and then putting it into a word document and enlarging it, it is obvious that this not a photo of reactor #1 except for the very right side of the reactor. The rest is another photo obviously spliced in. I don’t understand why Nuckelchen creates obviously fake photos. It doesn’t help us at all and puts into question all his work. Again, there is no link to an original photo for comparison. Propaganda is insulting.

    • Dr. Anne Lee Tomlinson Maziar anne

      Some people argue that the Unit #1 explosion was also a nuclear explosion. #3 was larger because of MOX fuel or other plutonium fuel experiment.

      The following video doesn’t argue this, but it does show also the difference between structural construction of #1 and #3:

      Fukushima Unit 3 ☢ Two Theories – 福島第一原発3号機

      • lokay5 lokay5

        Anyone who believes that the explosion of #3 was simply hydrogen and not nuclear really needs to do some SERIOUS research.

      • maax maax

        this video is interesting. I wonder where is the fuel of the pools at reactor 1 and 3, now.. How much fuel was in these pools? Are pools still in activity now?

        • Kevin Kevin

          It is an interesting video. The design information regarding the differences between one and three struck me for a couple reasons. First off, through all the debate comparing the two explosions this was not mentioned to my knowledge. The presumption was they were all built the same. This interests me because there is a reason for the differnet designs. What is that reason? It seems logical to presume that reactor three was reinforced and built stronger because of the potential more serious breach. Which leads you to wonder why? What were they doing there? Could it be that this was the reactor that was producing materials unrelated to the sole purpose of providing electricity? IF so that opens a serious can of worms and may explain why this point was never introduced into the discussoins comapring the two explosions.

          With respect to your questoins about where the fuel is. That is the bone of contention and the source of unending debate. The range is vast and the misinformation ran=mpid.

          My feeling is that with reactor three both the core and the SFP, were breached at the time of the explosion releasing serious amounts of really nasty stuff and a serious misinformation campaign has since ensued to cover it up.

  • BreadAndButter BreadAndButter

    Thanks again Arnie, for your input. Let’s hope the idiots who put up the new reactors in Georgia will listen.

  • Hi everybody! I’ve been too busy recently to take part of the discussion but have been reading actively. I just thought – not being an engineer – but having heard that large buildings are very sensitive to pressure changes. I visited some convertion page
    there you could change pounds per square inch into something more familiar to you. For example 125 pounds/sq inch is equal of having almost 88m of water pressing you, so if you have 1 square meter with 125 psi pressure it means that weight of nearly 88 tons is pointed on this single square meter. so if your containment vessel is 10x10meters = 100 square meters it equals about 8,8 million kg force. Though you have many thick bolts, they may be giving after when such forces are targeted on them. Correct me if I have understood wrong!

    • Spectrometising

      Nice work NONUKEBOX !!
      I like that elaboration on the question of “125Psi”.

      • Thanks Spectrometising! Hope I didn’t do any bad calculations. Maths has never been my strength! But we have had many accidents with snow and large buildings here in Finland: the engineers and architects haven’t been able to count the structural strenth of new buildings and after a moderate snowfall and the weather becoming warmer the buildings have just collapsed. They have been discussing about miscalculations in total masses of snow. When you have a large building, the total weight can be hundreds of thousands of kilograms. It’s a question of square meters.

  • And the weight for a train with 7 railroad cars is about 416 tons – under half a million kg – and a train with 100 ship steel containers weighs 2 million kg – just to be compared to that 8 million kg force lifting up the containment vessel lid. I think Arnie knows really what he is speaking about:-)

    • Kevin Kevin

      I agree Arnie does know what he is talking about and thanks for your thoughts on the 125 PSI issues people have wondered about, including myself. It just sounded low to me and I was stunned by the “flaw” (Arnie has commented on this lots in the past) and the fix usng the vents.

      Arnie does alot of interesting stuff. But when there are glaring conflicts between the data and what he presents I think it only obvious clarify. I also think it is important. Many people believe he is nothing but a shill for the industry. “The Damage Control Guy”

      I have looked at all of his work on this and have noticed his nuanced positioning on an array of issues. All of which suggests to me that in order for him to continue commenting and maintain his credibility he needs to address the gap between what he presents and what the facts have bore out.

      • Spectrometising

        Thanks Kevin. I take Arnie with a grain of salt. For instance his experiment showing hydrogen blowing up in a plastic bottle without safety glasses. I passed off some of his explanations as being “oh well, it’s the best we have” kinda attitude, but like yourself, i would like him to clarify more often.

        Let me also add that i am still not totally convinced that 120 Psi is a good figure. I need to check on maximum pressures for 2 inch steel of say a sealed, one piece vessel that is of the same dimension but without the steel bolts.

        Those kind of figures are accessible.

        Something does not sound exactly right. I am going to hazard a guess and admit i am still probably just as skeptical about the video as you are.

        I take a beam of light and if i don’t get an exact spectrum signature, i do not buy it and put it in the “beliefs” basket.

        • Kevin Kevin

          Oh yeah,

          With respect to the pressure issue.

          Its a non issue in my view. A minor detail at best.

          The point, which seems consistent is that the pressure seems low to lift that sort of engineered cap. Regardless, that is just a laymans observation. The fact is that I take Arnie at his word on this one, and the test proved the cap lifts. At what pressure and how big the bolts are, does not matter. I personally found it odd, as it looks like an adequate design but obviously it is/was not.

          The issue that I agree with Arnie on, is that in light of this 40 year old study, and with the understanding that PWR’s withstand higher pressure, it seems obvious that a “vent” was not the way to go but rather a redesign. That said, Redesign is expensive and clearly was not doable in the eyes of the industry. And given the total design failure, not the least of which, storing spent fuel in what was originally intended as a temporary holding pool for extracting and replacing rods, was an abysmall failure. Obviously who ever designed it must have realized that the temp storage pool would become the home for spent fuel given that there is nowhere else to put it and they should not have stuck it on top of the reactor. Or at least designed in a need to remove it as quickly as possible or make it smaller. Smaller makess sense to me. If you were intending to simply use the pool in reactor maintenance and replacement no need for it to holk hundreds and hundres of rods. It only lends the pool to be used for purpose other than the so called design, but i digress.

  • Kevin Kevin

    Thanks Spectrometising.

    I think it is important the we all think critically when presented with any information, regardless of source, from Arnie to NRC to TEPCO to the Media, government and supporting agencies. The one thing I do know, is that information in this industry is managed by professional issues management teams with vying agendas, so it is important to sort the pepper from the flyshit as best we can.

    In this instance, the facts are glaring, the conflict stands out like a sore thumb and the trail of misinformation leads to places that put people at risk. Therefor it is in Arnies best interest to address the concerns that arise from the information he presents as best he can.

    Thanks again.

  • Spectrometising

    Got it!!! Kevin…guys, check this out!!
    Here is why the bolts may not have held. And possibly explains a bit more Arnie Gundersen.
    This document says it all.

    • Interesting, Spectro. There is definitely an issue with corrosion of extraneous pieces-parts in PWRs due to the habit (and it’s a nasty habit imo) of controlling reactivity in the core with boron rather than by adjusting control rods.

      This is not, however, an issue at BWRs, where boron is NEVER added to the RCS to control reactivity because the same water that picks up heat directly from the core is the same steam that turns the turbines. It would crap the turbines up so badly they’d have to be replaced every time they refueled.

      They have been adding boron to emergency cooling water at Fukushima-I’s reactors 1, 2 and 3. Because there’s no reason not to, those cores and vessels are total trash and will never turn a turbine again. That was a foregone conclusion the moment they decided to use seawater.

      Boron corrosion could not have contributed to the leakage of steam and gas pressure from the head(s) at any of those reactors early in the accident, because there wasn’t any boron in the coolant water until several days after the earthquake/tsunami – and after the buildings blew up.

      • Kevin Kevin


        But the issue remains.

        Arnie needs to address the conflict in his presentation in the facts with respect to cause of explosion at reactor one.

        • I thought he had addressed it. But I admit I haven’t watched the video – I’m video-limited here. It is true that pressure testing failed at several BWRs right at DB [Design Basis] level when they WERE tested. Bolts loosened, gaskets failed. That is known, hope you’ve seen that documentation so I don’t have to go looking for it…

          Design testing, and I’m pulling on memory here so it’s gonna have some leeway, was right around 75 psig. Which, given my examples of pressure differentials I’ve encountered (and are part of regular airplane lore) is very, very considerable at a mere 3 to ~32 psig. Wrapping your head around that may be difficult – we can all apply 100 pounds of force to a drill or nail without any trouble – but we’re not talking a point focus here. We’re talking atmospheres, per square inch. That’s… positively explosive.

          Just seems to me that Arnie – as an engineer – can invoke engineering concepts without having to first educate the lay public in the basics of what all those concepts mean in terms of f=ma. I surmised very early on in the first 24 hours or so of the situation at Fukushima that they might very well run into this problem. Back when ‘latest’ news was that they wanted to vent but they claimed they couldn’t until Kan signed off on it. Which was horsehockey, but that’s another story…

          I asked a nuke apologist at another site WHERE they were venting, because there’s the hydrogen issue to consider. He flat denied hydrogen was possible, and said they must vent to stacks. So I asked where the evidence (steam from the stacks) was, because there wasn’t any. Hydrogen during nuclear accidents was absolutely verboten in general conversation until all three reactor buildings at Fukushima blew up. They NEVER would have admitted it. And yes, it probably did get loose from the heads. That was a no-brainer if you know the systems.

          • Kevin Kevin

            The video shows the steam rising from the smoke stacks, which also raises the question of this caused hydrogen to get into the secondary containment building.

            The issue as I have repeatedly said, is not with the bolts or the pressure on the cap. I agree with Arnie that the testing bore this out. The issue is, as admin posted in the post immediately following this one, is that the EQ damaged the containment, radiation was leaked and subsequently there was an explosoin. Arnie starts his video by avoinding all of this and focusing on issues after the tsunami by saying ” I want to focus on what happened after the tsunami” and not before wherby sidestepping the evidence that the EQ started the chain of events leading to the explosion and meltdown.

            • I haven’t yet seen a full technical analysis of the sequence(s) of events at Fukushima-I, so I haven’t yet been able to track everything back to various single and multiple point failures. That would probably take me years even if I did have the sequence of events straight from the control room computers to work with. And God only knows if they had any kind of realistic seismic monitoring at the time. North Anna didn’t, and I was there when they exposed the 15-foot wide fault line that ran right through the center of the containments for all 4 planned reactors. Go figure…

              But the #1 Prime Suspect on how hydrogen gas got from the melting reactors into the basically unshielded upper levels of the reactor buildings at Fukushima would be the containment heads. All three of ’em. Because all three of them are GE BWRs, and all three of them had containment heads known not to hold pressure at or above design basis [DB]. Had the vents worked properly, the gases (and steam) would have been sent out of the vent stacks, and THEY would have blown up instead of the reactor buildings. Honest.

              That said, yeah. I expect most all of the worst problems (speaking LOCA) at Fukushima were the result of the earthquake rather than the tsunami. The tsunami just took out the EDGs (what little power they had), and washed some of the broken piping away.

              • Dr. Anne Lee Tomlinson Maziar anne

                Some say that the earthquake released large amounts of methane and they were methane explosions which are very hot and the heat caused a nuclear chain reaction and nuclear explosion.

              • Kevin Kevin

                I am not asking for what is humanly impossible JoyB. Nor do I expect Arnie to be superhuman and lay out every detail. However when he presents an alternate theory to the already established facts he has to at least explain why he dismisses them in preference of the new information he is presenting. Or at least include the facts in the presentation and why he believes they are not the cause. Instead he ignores them in this case. Literally sidesteps them by starting his analysis after these facts and then works to build an alternate course of events. That raises a real red flag for me.

  • Spectrometising

    Thanks JoyB. “The samurai sword for system components”.!!

    Could you please annotate your abbreviations??
    Otherwise a good partial explanation i guess.

    So the head bolts are not the main issue and that although i thought there might be something in it, there is not so, thanks for the clarification.

    Beyond that: …………………………………………………………………..The main issue is that it (Boric acid.) is a death sentence for the components. Particularly if the temporary plumbing in place is undergoing rapid corrosion and has cracks or leaks.

    It is pretty blindingly obvious the reactor vessels will never do anything again so it is wasted effort mentioning them.

    Boric acid is poison for neutrons and the samurai sword for system components.!!

    • Spectrometising

      Ok…Sorry JoyB..You have been explaining things at length. (With and without annotations.
      I need some sleep

    • Sorry for my shorthand, Spectro. PWR = Pressurized Water Reactor. Like TMI, like San Onofre, like the majority of nukes in this country. RCS = Reactor Coolant System. The water that is heated up by direct contact with the core. In a PWR that is a (supposedly) closed system. The Feedwater system is what gets turned to steam to turn the turbines, it is not supposed to have any boron in it because boron is so notable for corroding metal pieces-parts. Like turbine blades.

      A BWR = Boiling Water Reactor. Like those at Fukushima that melted down. In those systems the same water that is in contact with the core is used (when it’s been turned to steam) to turn the turbine. So they don’t add boron to that reactor water at all in normal operation. Just like with the decision to use seawater to try and keep the melting cores cool, adding boron would have destroyed the system. Both seawater and boron meant TEPCO knew those reactors were toast.