Fukushima Confusion

Kevin, who is an ex-nuclear physicist with over 20 years experience of working in the industry has been providing an interesting commentary on the developments at the nuclear plants  in Japan after the earthquake. I thought readers might be interested (Update here and and further comment on Reactor 3 explosion here):

I don’t know if you’ve been following it but watch this (close up of explosion at ~+49 seconds – you can see the flash from burning hydrogen (released from molten fuel/coolant reactions within the uncovered core) propagating to the left of the ‘smoke’).

While I was watching BBC news some ‘nuclear expert’ from Chatham House was playing down what was happening at the Fukushima nuclear power plant (NPP). They showed aerial views of the NPP and it was evident that something very wrong had happen to the northern most reactor’s containment building and this so called ‘expert’ was trying to play down it’s significance. In contrast as soon as I saw the TV camera images my immediate reaction was OH F**K!!! as they showed the ‘un-clad’ steel framework of the containment building.

Sure enough a few minutes later that video above was shown and the ‘expert’ looked rather red-faced.  Clearly it showed a very large explosion within the reactor containment building and judging from the force of it most likely from a hydrogen gas explosion in combination with a sudden steam release from a ‘molten fuel/coolant interaction’ in the reactor core.  As far as I’m concerned it’s now patently obvious that the BWR’s pressure vessel has been breached for quite sometime and we haven’t been told that this was the case as this type of hydrogen build up that leads to an explosion like this takes a while (several hours) to build up.  One story is that the explosion was from hydrogen storage containers, but that explosion is from a lot of hydrogen, and why would so much hydrogen be stored at a nuclear site?

IMO it’s clearly a hydrogen explosion. You can see steam to some extent vented after the initial explosion but all four sides and the roof are blown out with quite some force. The roof didnt collapse’ as Roger Harrabin put out on BBC News a few minutes ago. The reactor pressure vessal has clearly been breached and if thats what they mean by ‘roof collapse’ then may be. IMO at this moment there will be lots of radioactivity being released from the reactor as there is clearly now NO containment building left after that explosion.

[Update from AP/Google news]:
It turned out that officials were aware that the steam contained hydrogen, acknowledged Shinji Kinjo, spokesman for the government Nuclear and Industrial Safety Agency. More importantly, they also were aware they were risking an explosion by deciding to vent the steam.

The significance of the hydrogen began to come clear late Saturday:

—Officials decided to reduce rising pressure inside the reactor vessel, so they vented some of the steam buildup. They needed to do that to prevent the entire structure from exploding, and thus starting down the road to a meltdown.

—At the same time, in order to keep the reactor fuel cool, and also prevent a meltdown, operators needed to keep circulating more and more cool water on the fuel rods.

—Temperature in the reactor vessel apparently kept rising, heating the zirconium cladding that makes up the fuel rod casings. Once the zirconium reached 2,200 degrees Fahrenheit (1,200 Celsius), it reacted with the water, becoming zirconium oxide and hydrogen.

—When the hydrogen-filled steam was vented from the reactor vessel, the hydrogen reacted with oxygen, either in the air or water outside the vessel, and exploded.

The gas was vented under control from the (intact) reactor into the building and only blew off the cladding (picture here; cut-away schematic here).

Both Fukushima plants required pressure release: http://www.reuters.com/article/2011/03/12/japan-quake-tepco-radiation-idUSTKG00706720110312

The Japanese have been using BWR technology for quite sometime now and as a UK ex- advanced gas-cooled  reactor (AGR) designer and physicist I’ve never liked the idea of having a nuclear reactor technology that is not dissimilar to a ‘kettle’ being used to generate nuclear electricity especially when the NPP based upon that design is built on a known fault line, especially when it’s built on the most active fault line (the ‘Ring of Fire’) on the planet.

I’m currently following the coverage of the Fukushima incident on the internet and MSM TV (BBC news and RT) and there is certainly a lot of mis-information/inaccurate information being given out mainly due to the fact that there are in two Fukushima sites both of which appear to have been affected by the earthquake.  Wikipedia and Google maps may contribute to the confusion. referring to info from Japan Nuclear, Fukushima II (Daini) is in the South; Fukushima I (Dai-ichi) is to the North (pop up map here).

The Daini site has four Mark II BWR reactors and the Dai-ichi site has six BWR reactors largely of the Mark I type. Big difference in the site layouts etc.

Here is Fukushima II (Daini)

and here is Fukushima I (Dai-ichi)

It’s all rather confusing though just now as it looks like different reactors at the Fukushima I and II sites appear to be having problems.

The best information so far has come from World Nuclear News [this site seems to be updated when new information is available].  This confirms my initial impression from the news footage that it was the Dai-ichi reactor that had experienced the explosion; it is in fact the northern plant and is, according to Japan Nuclear, Fukushima I. It confirms there are problems at both sites.

Information below and Picture from: http://www.world-nuclear-news.org/RS_Battle_to_stabilise_earthquake_reactors_1203111.html                                    

Fukushima Daiichi

Unit 1
– 439 MWe BWR, 1971
– Automatically shut down
– Water level decreasing
– Pressure release implemented
– Explosion observed
– Containment believed intact
– Seawater injection has started
Radiation levels unchanged after explosion
Unit 2
– 760 MWe BWR, 1974
– Automatically shut down
– Water level lower but steady
– Preparations for pressure release
Unit 3
– 760 MWe BWR, 1976
– Automatically shut down
– Preparations for pressure release
Unit 4
– 760 MWe BWR, 1978
– Shut for periodic inspection
Unit 5
– 760 MWe BWR, 1978
– Shut for periodic inspection
Unit 6
– 1067 MWe BWR, 1979
– Shut for periodic inspection
Fukushima Daini
Unit 1
– 1067 MWe BWR, 1982
– Automatically shut down
– Offsite power available
– Water level stable
– Preparations for pressure release
Unit 2
– 1067 MWe BWR, 1984
– Automatically shut down
– Offsite power available
– Water level stable
– Preparations for pressure release
Unit 3
– 1067 MWe BWR, 1985
– Automatically shut down
– Offsite power available
– Water level stable
– Preparations for pressure release
Unit 4
– 1067 MWe BWR, 1987
– Automatically shut down
– Offsite power available
– Water level stable
– Preparations for pressure release

From the NIRS Fact Sheet on Fukushima:

On June 17, 2010, the same Fukushima I-2 reactor experienced a loss-of-power accident.According to Citizens’ Nuclear Information Center, “On June 17, Tokyo Electric PowerCompany’s Fukushima I-2 (BWR, 784MW) scrammed due to a problem with the generator.Power was lost for a time, because the switchover to the offsite power supply was unsuccessful.As a result, the feedwater pump stopped and the water level in the reactor core fell about 2meters. The emergency diesel generator started up just in time, so the Emergency Core CoolingSystem was not activated. The water level was restored by an alternative pump in the coreisolation cooling system

So there is a prior history of backup system failures on the adjacent reactor – that’s important and according to CNIC a history of ‘damage cover up and data falsification’.

http://cnic.jp/english/newsletter/nit92/nit92articles/nit92coverupdata.html

Hopefully, if you haven’t worked it out already and if you’ve got this far, you’ve realised that even though I’m ex-UK nuclear industry and could do very well out of a re-emergence of nuclear power generation in the UK, I don’t think nuclear power generation should get a free ride off the back of climate change alarmism.

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22 Responses to Fukushima Confusion

  1. boballab says:

    Kevin:

    The Japanese Government has stated it is Fukushima I that had the explosion and they have put up a map showing the evac zones, 20Km from Number I (Northern) and 10Km from II (the 10 Km zone around the southern one sits inside the Northern one).

    Watch this straight from Japan (in English) here:
    http://wwitv.com/tv_channels/6810.htm

  2. boballab says:

    Oh btw that link is to NHK and you will just love the “Wall Falls down” statement which they will re-air.

    • Verity Jones says:

      Wall falling down – no way.

      I see some good comments from yourself and others over at E.M. Smith’s:
      http://chiefio.wordpress.com/2011/03/12/japan-nuke-plant-explosion

      I understand the coment about it being consistent with “deflagration” and agree.

      Kevin and I were debating locations and numbering of the plant is definately confusing. It seems it is Daiichi, “Fukushima I. The confusion arose I think as the media were reporting I, but saying Daini. I will modify the above as I think it only added to the confusion.

      • Verity Jones says:

        FWIW the confusion arose because a Google Maps/Google Earth search found #2 and #3, but we initially missed #1. The news footage didn’t seem to tally with the Daini plant but definately not with #3.

        North to South:
        1. 37.421319, 141.032939 – Daiichi labelled as Fukushima I on Google Earth; 6 reactors; two piers
        2. 37.316562, 141.026512 – Daini labelled as Fukushima II 4 reactors; two piers (at first we thought this was Fukushima I)
        3. 37.235877, 141.014952 – ??? 4 reactors; only 1 pier (we initally wrongly assumed this was Fukushima II)

      • boballab says:

        The “Wall Falling” down spiel by the Japanese Government is so that people do not panic and flood out into already stressed transport networks and is also something I have heard before (not those exact excuses but in the same vein). Way back in 1979 growing up in a little town called Cochranville in southeastern Pennsylvania, I watched the Three Mile Island news coverage. I remember how they kept stressing over and over that there was no meltdown in progress because if there was I would die a horrible death due to living in the area where everyone dies when that happens. Turns out of course that the core was melting down but there was no way they could evac all the millions of people in time, so why create a panic.

        When you have personally lived through something once before, you can typically smell the BS when it is tried later on.

  3. KevinUK says:

    boballab

    Verity has summarised why I was initially confused very well above. I will now no longer assume that Google is right when it comes to the labels it attaches to places on its map. However Google Maps/Earth is an excellent and would not like to have to make do without it.

    Thanks to you good self and other poster son WUWT my confusion as to which site the explosion occurred at was soon corrected.

    Following the comments on WUWT it would appear that my initial suspicions and deductions (largely based on the video of the explosion) on the extent and cause of the explosion have been confirmed (see Update above).

    Personal experienc eof other nuclear incidents has taught me to look somewhat beyond the offical announcements, hence my immediate skepticism in regard to teh official explanations of the cause of the explosion. I can understand why the authorities don’t want to panic the local population as sadly all too often the panic can lead to more deaths and injuries due to people attempting to flee quickly from the area rather are caused directly by the incident. In other words it’s important to control (and use) the media as much as possible in these situations even arguably and justifiably to feed them mis-information.

    My main concern this morning was what was happening in regard to the other north east coast Japanese nuclear sites. It appeared to me (as was subsequently confirmed) thatthere where in fact several incidents and the media appeared to be confusing them (still are it would seem).

    I got particularly pissed off with the so-called ‘nuclear expert’ from Chatham House (http://www.chathamhouse.org.uk/about/directory/view/-/id/86/) who BBC News had wheeled out who was clearly getting it wrong on almost every count. I’m ex-UKAEA myself and this prat is a former ‘information officer’ which means he basically knows diddly squat about the actual physics and engineering of nuclear reactor systems yet he’s an expert according to the BBC. In contrast Russia Today had a what at first impression what appeared to be ‘a wet behind the ears’ kid but he was pretty much spot on most of the time.

    • boballab says:

      Kevin:

      Basically I am ignoring what the talking heads on US/UK news outlets are saying and just paying attention to what is being said (or not said) on NHK which is what is going out to Japan own citizens. Also I found an English language page to the Japanese version of the US Nuclear Regulatory Agency. You can see their reports here: http://www.nisa.meti.go.jp/english/

      In the reports it breaks it down first by plant then by reactor. So in the latest report you see that Fukushima Plant I units 1, 2 and 3 are having problems:
      Article 15** of Act on Special Measures Concerning Nuclear Emergency Preparedness (Fukushima Dai-ichi, Units 1 and 2)
      (** Nuclear emergency situation)
      Situation of power source to recover water injection function at the Station.
      -Cable from electric power generating cars are under connecting work(as of
      15:04, March 12)
      -Pressure in the containment vessel has arisen. Steam release is
      undertaking in order to relieve pressure.(as of 14:40, March 12)
      -A radiation level exceeding 500 microSv/h was monitored at the site
      boundary(15:29, March 12). A large motion occurred due to an earthquake
      with close epicentre and an large sound was issued near Unit1 and smoke
      was observed.
      -Unit 3: As the automatic trip of the HPCI, coolant injection using other
      systems tried but failed. The reactor injection function was lost. (05:10,
      March 13)

      And at Fukushima Plant II Units 1, 2 and 4 are having problems:

      Article 15** of Act on Special Measures Concerning Nuclear Emergency Preparedness (Fukushima Dai-ni, Units 1,2 and 4)
      (**Nuclear emergency situation)

      http://www.nisa.meti.go.jp/english/files/en20110313-3.pdf

  4. tonyb says:

    Kevin

    You said;

    “Hopefully, if you haven’t worked it out already and if you’ve got this far, you’ve realised that even though I’m ex-UK nuclear industry and could do very well out of a re-emergence of nuclear power generation in the UK, I don’t think nuclear power generation should get a free ride off the back of climate change alarmism.”

    We already have a yawning gap in our energy equation -if nuclear is removed that gap becomes unbridgeable as there are simply not sufficient ‘renewables’ to provide the energy we need in the UK.

    Are you saying ALL nuclear power is unsafe or are some forms acceptable? If its all a no go area what do you suggest we use as energy (I’d go for coal and gas from shale 🙂

    Tonyb

  5. Tony,

    What I’m saying is that teh UK’s first generation of nucler reactors was justified on the basis of a lie. The lie was that we would have cheap energy. In reality we built the first generation of Magnox stations and operated them in order to produce plutonium for the UK’s independent nuclear deterrent. Even some of the second generation Magnox’s were used for effectively breeding plutonium.

    Because of this we have a huge legacy of nuclear facilities (fuel fabrication plants, power reactors and graphite piles and fuel reprocessing plants) that need to be decommissioned and the waste arisings from those decommissioning activities dealt with. The majority of these facilities are in a state of long-term ‘care and maintenance’ which IMO is a euphemism for ‘so long as the outside looks OK no one is going to worry too much about the state of whats inside.’ IMO before we embark on a new generation of nucler power plants we should at the very least have a major programme initiated that deals with these nuclear legacies and stops this whole farce of keeping them under long term ‘care and maintenance’.

    Now to answer you question as to what we shoudl be doing inthe eventthat we don’t build more nuclear power plants within the next say 10 years, my answer would be that we need to build more replacement coal fired power plants and stop the stupidity of insisting that the must have CCS. I think we should be drilling/exploring for shale gas NOW and as much as we can. We should be phasing the closure of ‘life expired’ nuclear power plants with the start up of new fossil plants (coal and gas). We should be opening up our UK coal mines once more and using the coal to generate ‘town gas’ again if needed. We should be building more liquid natural/shale gas importing facilities so that we can take full advantage of the large natural gas reserves (e.g. Sakhalin Island) and shale gas discoveries in the US and Europe (Poland and Germany).

    We should NOT be subsidising the purchase of electric cars as they are futile and in combination intermittent wind power will cripple our electricity supply. If we hav eto have an alternative fuel for transport then it should based on natural gas/shale gas. Once we’ve developed better batteries then maybe it might make some sense to have electric cars that can are fast re-chargable using electricity from a fleet of new nuclear power plants but probable not within my lifetime.

    If we get around to actually building any new UK NPPs in what remains of my lifetime then they should be based on existing proven technology and not on some as yet to be proven (but nonetheless promsing technology) like LFTR. In my opinion fusion power generation will not work even within my grand child’s grand child’s lifetime, let alone mine.

  6. KGB says:

    Fukushima 1 is a BWR seriers 3 supplied by GE. In the event that excess pressure in the primary containment’s drywell, and /or the wetwell, requires relieving, it is my understanding that the outstack system is designed for such use thereby avoiding the obvious danger of venting an hydrogen / air explosive atmosphere within the enclosed space of the outer reactor building. There is nothing “controlled” about the unintended destruction of the outer containment structure. Of the many questions in my mind is how H2/O2 entered this outer containment – human error or structural failure ?

    • boballab says:

      KGB:

      Designed Safety features don’t always work the way they are supposed to. The classic example of this is what started the Three Mile Island accident:

      Due to the loss of heat removal from the primary loop and the failure of the auxiliary system to activate, the primary side pressure began to increase, triggering the pilot-operated relief valve (PORV) at the top of the pressurizer to open automatically. The PORV should have closed again when the excess pressure had been released and electric power to the solenoid of the pilot was automatically cut, but instead the main relief valve stuck open due to a mechanical fault. The open valve permitted coolant water to escape from the primary system, and was the principal mechanical cause of the crisis that followed.[11]

      http://en.wikipedia.org/wiki/Three_Mile_Island_accident

      Now the Fukushima I reactor I unit is a Mark II BWR, not a Mark III, designed in the 1960’s and put into operation in 1973. The major difference between a Mark I an II was the addition of the stacks due to the lack of confidence in the Mark I’s

      Though the present fleet of BWRs are said to be less likely to suffer core damage from the “1 in 100,000 reactor-year” limiting fault than the present fleet of PWRs are (due to increased ECCS robustness and redundancy) there have been concerns raised about the pressure containment ability of the as-built, unmodified Mark I containment – that such may be insufficient to contain pressures generated by a limiting fault combined with complete ECCS failure that results in extremely severe core damage. In this double failure scenario, an unmodified Mark I containment can allow some degree of radioactive release to occur. This is supposed to be mitigated by the modification of the Mark I containment; namely, the addition of an outgas stack system that, if containment pressure exceeds critical setpoints, is supposed to allow the orderly discharge of pressurizing gasses after the gasses pass through activated carbon filters designed to trap radionuclides

      http://en.wikipedia.org/wiki/Boiling_water_reactor#Disadvantages
      (Note: I stripped out the gratuitous adding in about Fukushima I in this paragraph that had no citation. It wasn’t in the original correct article)

      However from direct reports from both the NISA (Japanese Version of the US Nuclear Regulatory Commission) and TEPCO (The operators of the plant they had to manually release pressure. That tells you the quake followed by the Tsunami damaged the automatic safety systems. Now the thing to keep in mind is that there is a great big source of H and O in a reactor: Water. When a reactor gets hot enough and at the wrong pressure the molecules of H2O thermal decompose into their component atoms.

      Thermal decomposition, also called thermolysis, is defined as a chemical reaction whereby a chemical substance breaks up into at least two chemical substances when heated. At elevated temperatures water molecules split into their atomic components hydrogen and oxygen. For example at 2200 °C about three percent of all H2O molecules are dissociated into various combinations of hydrogen and oxygen atoms, mostly H, H2, O, O2, and OH.

      http://en.wikipedia.org/wiki/Water_splitting#Thermal_decomposition_of_water

      Also when you expose fuel rods to air the Zirconium cladding has a bad oxidation process that produces more Hydrogen.

      So even though the Hydrogen explosions seen so far are not good things, they are better then the alternative of leaving the decomposed Hydrogen and Oxygen inside either the Containment Vessel or the Pressure Vessel. If left inside of either of them and have those explosions things would be much. much worse. This was also something that TMI also had to deal with:

      About 130 minutes after the first malfunction, the top of the reactor core was exposed and the intense heat caused a reaction to occur between the steam forming in the reactor core and the Zircaloy nuclear fuel rod cladding, yielding zirconium dioxide, hydrogen, and additional heat. This fiery reaction burned off the nuclear fuel rod cladding, the hot plume of reacting steam and zirconium damaged the fuel pellets which released more radioactivity to the reactor coolant and produced hydrogen gas that is believed to have caused a small explosion in the containment building later that afternoon.[17]
      http://en.wikipedia.org/wiki/Three_Mile_Island_accident#Consequences_of_stuck_valve

      On the third day following the accident, a hydrogen bubble was discovered in the dome of the pressure vessel, and became the focus of concern. A hydrogen explosion might not only breach the pressure vessel, but, depending on its magnitude, might compromise the integrity of the containment vessel leading to large scale release of radiation. However, it was determined that there was no oxygen present in the pressure vessel, a prerequisite for hydrogen to burn or explode. Immediate steps were taken to reduce the hydrogen bubble, and by the following day it was significantly smaller. Over the next week, steam and hydrogen were removed from the reactor using a catalytic recombiner and, controversially, by venting straight to the atmosphere.

      http://en.wikipedia.org/wiki/Three_Mile_Island_accident#Emergency_declared

      In conclusion these explosions while spectacular were not truly unexpected by any one that has experience in the industry/field. Kevin (Nuke Physicist), Myself (USN trained Nuke Operator) and other similarly trained people on other sites were stating that it was either a steam or hydrogen explosion right after #1 had it’s explosion, something the Japanese government nor the worlds news services state until over 13 hours later.

      • KGB says:

        Boballab,

        Thankyou for your explanation and in reply my apologies; I could have saved you the trouble as I am familiar with the principles you advanced. However having no experience of the USN’s safety case (although it was incorporated for Dreadnought), my point was that in no way is the destruction of the outer containment an intended consequence of venting the primary containment. Outstacks are incorporated into this design, and I stand corrected it is a BWR 1, but I believe it was modified following the design weakness you identifed. I don’t for one minute think there has been incompetence, unlike TMI and Chernobyl (See reports), so it seems unlikely that the excess pressure has been intentionally vented into the confined space of the outer containment with the foreseeable risk of a disruptive explosion and the endangerment of life. I can assure you that no such contingency would be sanctioned by the UK HSE’s NI as part of the safety case. So how; I wonder did the explosive mix accumulate in the containment building if the outstack, or other external venting systems were available. In closing my remarks I fully recognise the luxury of questioning this from the sancuary of a quiet office – one can only imagine the stress of those striving to engage safety systems in a severely damaged utility and having to resort to extreme measures. I hope their training was up to the mark and I wish them every success.

      • boballab says:

        KGB:

        That blue/gray Box shell is not a containment vessel. If you look at the after photos of the explosion you can see the top of the concrete containment vessel sticking up. Unlike in the US, or maybe even the UK, the building and the Containment vessel of the reactor are not the same thing at those plants. What you saw blow up was basically a weather guard for the equipment that surrounds the containment vessel. Example in the US they use big heavy concrete buildings and as in TMI there was an explosion in one of those building from Hydrogen venting along with steam, at Fukushima the lightweight structure was blown off exposing the heavy concrete containment beneath it.

        Was it intended to be primarily vented that way? No, however the primary method isn’t working and was one of the points I made : They can’t outgas through the stacks right now.

        The back up for that is to vent into that lightweight building. So keep that in mind the Stacks can not vent right now for whatever mechanical reason (Valve Stuck or pipe burst during quake/Tsunami) and are not an option.

        Did they want the building to blow? No, but it was always a possibility when they were forced to vent into it to keep the Containment Vessel and the Pressure Vessel from blowing.

      • boballab says:

        Forgot to mention this but NISA did a presentation on NHK about how and why they are venting the various reactors and where they are venting to. That is why, really you should give up on watching the US/UK coverage (They are all using mostly NHK’s video feeds) and get it straight from the horses mouth so to speak.

        For NHK World Service:
        http://wwitv.com/tv_channels/6810.htm

        For NISA:
        http://www.nisa.meti.go.jp/english/

        For TEPCO:
        http://www.tepco.co.jp/en/index-e.html

        Here is the latest from TEPCO:

        At approximately 11:01am, an explosion followed by white smoke occurred at the reactor building of Unit 3. It was believed to be a hydrogen explosion.

        According to the parameter, it is believed that the reactor containment vessel remains intact. However, the status of the plant and the impact of radioactive materials to the outside environment are presently under investigation. (previously announced)

        As of 1:30 pm, 4 TEPCO employees and 3 workers from other companies have sustained injuries (all of them are conscious). 3 ambulances are in operation to care for them and 2 have already dispatched the casualties to the hospital.

        As of 0:30 pm, the measured value of radiation dose near MP6 was 4μSv/h. The increase of the radiation dose cannot be confirmed at this time.

        As of 0:30 pm, the measured value of radiation dose at the monitoring post in Fukushima Daini Power Station located approximately 10 km south of Fukushima Daiichi Power Station remains at the same level.

        In light of the incidents that have occurred at Units 1 and 3, we are considering applying prevention measures to the wall of the reactor building to ventilate the hydrogen gas contained in Unit 2.

        TEPCO continues to take all measures to restore the safety and security of the site and are monitoring the site’s immediate surroundings.

        http://www.tepco.co.jp/en/press/corp-com/release/11031405-e.html

  7. KevinUK says:

    boballab,

    It’s really not looking very at all now is it? I’ve been watching the footage of the Reactor 3 building explosion this morning and the force of the explosion was much greater than that of the Reactor 1 building. A much more evident ‘flame’ can be seen following by subsequent ‘white smoke’ (steam) and ‘grey smoke’ (building debris). And a part of the building structure (most likely the top of the roof) can be seen blown up high into the air and falling back down to the ground.

    On some of the post-explosion zoomed in video footage shots, it’s clear that there has been much more extensive damage to the Reactor 3 building as a result of this explosion than was caused to the Reactor 1 building following it’s earlier explosion.

    “In conclusion these explosions while spectacular were not truly unexpected by any one that has experience in the industry/field. Kevin (Nuke Physicist), Myself (USN trained Nuke Operator) and other similarly trained people on other sites were stating that it was either a steam or hydrogen explosion right after #1 had it’s explosion, something the Japanese government nor the worlds news services state until over 13 hours later.”

    I used to work for the UK Atomic Energy Authority (National Nuclkear Corporation before that) and was fortunate in a sense at one point to seconded to the SSEB (for a couple of years) to help first commission and subsequently operate Torness NPS. As a result I was what UKAEA called an ‘attached staff member’ and so had ‘specially privileges’. Amongst them was the opportunity to regularly visit all the UKAEA research facilities at Windscale, Harwell, Winfrith, Risley, Dounreay and even Culhan (JET) and be briefed by experts on the UKAEA’s full nuclear and non-nuclear R&D programmes. As a consequence I’ve personally witnessed experiments that involved ‘clad balloning’, ‘molten fuel/coolant interactions’ and worked with the scientists/engineers that did ‘severe accident analysis’ modelling at Winfrith. I’ve also seen experiments which have convinced me that sodium-cooled fast reactors are not a good idea and have done a bit of ‘sodium spray’ modelling myself and have done lots and lots of gas-cooled reactor fault modelling and fault-tree analysis. I’ve also been responsible for many independent safety reviews of safety submissons (tht detail with changes to Operating Rules (ORs) and Identified Operating Instructions (IOIs)) to the CEGB amd SSEB’s Nuclear Safety Committees. I’ve also shared an office with the people who ‘validate PWR pressure vessel inspectors’ in the UK and so know quiet a bit about LWRs as well as gas-cooled reactors. Consequently I’ve ‘been around and seen quite a bit’ when it comes to nuclear safety and that’s probably why I’ve been ‘ahead of the curve’ in regard to working out what has most likely been happening to the reactors at Fukushima.

    It really doesn’t look good at all to me now. Although the official authorities are claiming that R1, R3 (and now R2’s) pressure vessels are intact I very much have my own doubts. I just hope I’m proved wrong. I think it’s now more likely than unlikely that at some point there will be a significant release of radioactivity from all three of the stricken reactors at Fukushima. Again I just hope I’m proven wrong. If and when this happens, the consequences of the uncontrolled release with be tiny in comparison to the devastation caused directly by the earthquake and tsunami.

    From a global nuclear industry perspective the problem will now be that this nuclear incident will now be perceived as a complete disaster and all reactor technologies will be now be ‘tarred with the same brush’ as unsafe. Little attention will be placed on the fact that these reactors are on a major fault line, suffered a beyond design level severity earthquake, yet all of them shutdown successfully. The actual problems have been caused by the subsequent tsunami knocking out all backup cooling systems and whatever contingency plans that were put in place have failed miserably. I don’t think this (failure of the contingency pans) is surprising given the devastation caused by the tsunami.

    • boballab says:

      Kevin So far NISA has found any damage to #3, however there has been very bad news about #2 unit. Turns out the S/R valve shut on it’s own unexpectedly and will not reopen. So right now they are unable to vent #2 or add in new Seawater to cool that core. That has me a lot more worried then the explosion of the outer building of #3. If you get Hydrogen explosion inside either the Pressure or Containment Vessels they can crack and leak/Release Radioactive material. The thing is if that happens no one on the outside would see it since the Blue/Gray building won’t go flying apart. The explosions energy would be used up cracking the either the Pressure/Containment vessel and not damage the outer building.

      Here is an example I used for someone else when watching those explosions:
      Light a firecracker and lay it on your living room floor next to to a small mason jar half full of liquid mercury. When the Firecracker goes boom, you get a flash, sound, flying dust and very likely a mark on your floor, but as long as that jar doesn’t crack nothing really bad happened.

      Now take a second Firecracker and light it and seal it into that half full mason jar of liquid mercury (keeping the wick out of the fluid). Now sit it on the floor and watch it go Boom. Now this time form the same size explosion you will have a much bigger problem but it won’t look as spectacular as the first one.

      I agree with your thoughts on Liquid metal cooled reactors, the US found that bad things happen with them way to easily.

    • boballab says:

      Here is the latest from TEPCO on the explosion at unit #3:

      Press Release (Mar 14,2011)
      White smoke around the Fukushima Daiichi Nuclear Power Station Unit 3 (3rd release)

      At approximately 11:01am, an explosion followed by white smoke occurred
      at the reactor building of Unit 3. It was believed to be a hydrogen
      explosion.

      According to the parameter, it is believed that the reactor containment
      vessel remains intact. However, the status of the plant and the impact
      of radioactive materials to the outside environment are presently under
      investigation. (previously announced)

      As of 1:30 pm, 4 TEPCO employees and 3 workers from other companies have
      sustained injuries (all of them are conscious). 3 ambulances are in
      operation to care for them and 2 have already dispatched the casualties
      to the hospital.

      As of 0:30 pm, the measured value of radiation dose near MP6 was 4μSv/h.
      The increase of the radiation dose cannot be confirmed at this time.

      As of 0:30 pm, the measured value of radiation dose at the monitoring
      post in Fukushima Daini Power Station located approximately 10 km south
      of Fukushima Daiichi Power Station remains at the same level.

      In light of the incidents that have occurred at Units 1 and 3, we are
      considering applying prevention measures to the wall of the reactor
      building to ventilate the hydrogen gas contained in Unit 2.

      TEPCO continues to take all measures to restore the safety and security
      of the site and are monitoring the site’s immediate surroundings.

      http://www.tepco.co.jp/en/press/corp-com/release/11031405-e.html

      And from NISA:

      An explosion caused by hydrogen at Unit 3 of Fukushima Dai-ichi NPS (the 3rd release)

      1. Plant status
      After the hydrogen explosion at 11:01, pressure fluctuation in the containment vessel was observed. Afterward the pressure is becoming stable. It is considered that the vessel maintains its function of confinement.

      Fuel cooling status is under confirmation.

      2. Evacuation of local residents
      The number of the residents within 20km radius from Fukushima Dai-ichi Nuclear Power Station, NPS, waiting for evacuation or evacuating is 483 in total at 14:20 March 14. (Under confirmation)

      After the explosion at Unit 3, the residents were requested to shelter inside, but afterword the evacuation to outside of the 20 km area was resumed.

      3. Status of the injured
      According to the report from TEPCO, the number of the persons injured in the
      explosion is eleven (11) as of 16:00.

      http://www.nisa.meti.go.jp/english/files/en20110314-3.pdf

  8. thepoodlebites says:

    A dose rate of 4 uSievert/h = 0.4 mRem/h, (1 Sievert = 100 Rem). It takes about 100 Rem to induce radiation sickness so the dose rate is still very small. Technically, a radiation area is > 1 mRem/h, a high radiation area > 100 mRem/h (0.1 Rem/h). As a comparison, the dose rate within 1 quarter mile of Chernobyl was >1,000 Rem/h. As a result, 28 brave fire and rescue workers died trying to bring the accident under control, even though they knew they could receive a lethal dose within 10 minutes. This may turn out to be (I hope), no more than Three Mile Island, very low-level exposure, 100 mRem, total dose.

  9. thepoodlebites says:

    OK, latest readings from Fukushima, 751.2 uSv/h, or 75 mRem/h. Definitely upgraded to a radiation area but not a high rad area yet.
    http://www.straitstimes.com/BreakingNews/Asia/Story/STIStory_644923.html

  10. KevinUK says:

    boballab

    Have a look at thsi image

    Zoom in using Ctrl and +.

    According to The Register that is just ‘cosmetic’ damage

    http://www.theregister.co.uk/2011/03/14/fukushima_reactor_update/

    Where would you say the ‘white smoke’ (steam) is coming from in that image?

    The radiation levels are low right, so where are the people dealing with the incident with R2?

  11. Pingback: Fukushima: Reactor 3 blast looks serious | Digging in the Clay

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