Fukushima Daiichi nuclear disaster

Discussion in 'world politics, current affairs and news' started by Barking_Mad, Mar 11, 2011.

  1. coley

    coley Well-Known Member

    Ooh you cynic you, how could you imagine such a scenario? Though his mates are now seeing themselves as Sperm whales and are getting pretty desperate.
     
    teqniq likes this.
  2. Tankus

    Tankus living someone else's dream.

    Strike price is higher than Hinkleys ....but you just know Hinkleys not going to stand still ...Swansea lagoon will come down ....La Rance at 50 years old ...some of the cheapest production prices in France and has recouped its capital cost ...No nuclear plant has done that ..... ever ..!.....as we still dont know what the fuck to do with their long term legacies 50 years on , but we do know its going to cost the earth !
     
    existentialist likes this.
  3. coley

    coley Well-Known Member

    Swansea's, costs are AFAIK, fixed at the agreed strike price,as are most renewables, unlike Hinckley who are index linked and whose charges could be astronomical given even a short term jump in the COL index.
     
  4. elbows

    elbows WoeTimer

    Well 5 years sure went by fast!

    I knew it would take ages before we got visual confirmation of the state and location of the melted reactor cores. I knew it would be some years, but I was hoping it wouldn't be this long.

    Reactor 2 has always been of special interest to me for reasons I won't bore on about right now, and they were getting slowly closer to putting an inspection robot into the area below where the reactor vessel is/was. But efforts to decontaminate an area in front of a pipe where they intend to insert the robot have not been a great success so that plan has stalled for now, pending trying another decontamination technique if they can come up with one, or complete change of plan.
     
  5. elbows

    elbows WoeTimer

  6. mwgdrwg

    mwgdrwg Be a Pisces. Jam.

    Is the cooling back on in the Fukushima nuclear mess?

    I was watching NHK last night and they kept mentioning that the cooling was offline, but the rods would remain cool for the time being.
     
  7. elbows

    elbows WoeTimer

    It was cooling for one of the spent fuel pools, in this case the reactor 3 spent fuel pool. The cooling can be off for these pools for quite a long time before it becomes a big issue. Especially since the pool with most fuel & heat was reactor 4 pool and that got successfully emptied almost a year ago.

    In the end I think this cooling outage lasted about an hour and 40 minutes.
     
  8. bi0boy

    bi0boy Power User

    Are they still collecting leaking tritium in a zillion tanks? I'd have thought they'd have run out space by now :D
     
  9. elbows

    elbows WoeTimer

    Scratch that - turns out it was a pool at reactor 3 of the other nuclear plant at Fukushima (Fukushima Daini). This plant narrowly avoided in 2011 the sort of meltdowns & leaking that occurred at Fukushima Daiichi. However what I said about there being a reasonable time window where pool cooling can be off without anything bad happening is still true.
     
  10. elbows

    elbows WoeTimer

    Too much water remains an issue that they are slowly trying to improve, with rather mixed results. I dont pay as much attention these days but as far as I know they are still doing work to make less groundwater enter the area, and they are also looking at reducing the rate at which cooling water is pumped into whats left of reactors 1-3. As best I can recall not all the water ends up stuck in tanks - some is cleaned up to a certain extent and then reused as cooling water.
     
    bi0boy likes this.
  11. TopCat

    TopCat Zap it!

    How does radiation fuck up and disable a robot?
     
    Pickman's model likes this.
  12. DotCommunist

    DotCommunist slowtime

    same way it fucks a human up, it disrupts processes at a basic level- particle radiation knocking out circuitry the same way it knocks your cells about and gives you radiation poisoning. Particle radiation is very small but it is still a particle moving quick as fuck
    iirc!
     
    TopCat likes this.
  13. elbows

    elbows WoeTimer

    Is there a particular robot death that prompted the question?

    Radiation can certainly damage electronics. But most of the robots they lost in Fukushima so far were due to physical problems such as the robot getting stuck, or its cables getting stuck. They even managed to crash a drone on the roof of reactor 2 at some point in the first months of the disaster.
     
  14. T & P

    T & P |-o-| (-o-) |-o-|

  15. coley

    coley Well-Known Member

    "In December, the government said the estimated cost of decommissioning the plant and decontaminating the surrounding area, as well as paying compensation and storing radioactive waste, had risen to 21.5tn yen (£150bn), nearly double an estimate released in 2013"

    And you still have people supporting nuclear power!
     
    muscovyduck likes this.
  16. xes

    xes F.O.A.D

    is this still in meltdown mode then, or is this the residual waste left over after it was secured?
     
  17. T & P

    T & P |-o-| (-o-) |-o-|

    I don't think it's in meltdown (but then I have literally zero technical knowledge on such matters, so it's just my guess).

    But it might take a long time yet to bring under full control. In the associated article (link on the same page) they say they're having to pump through 300 tonnes of water a day to keep the failed reactors cool. The Japanese authorities are lobbying to be allowed to dump 800,000 tonnes of contaminated water back in the sea eventually. That's 7 years' worth of water pumping. But if they started pumping & storing shortly after the incident, I guess that means they estimate 1-2 more years of it.
     
    Last edited: Feb 3, 2017
  18. xes

    xes F.O.A.D

    I thought they already were pumping the water back into the sea? I'm sure I've seen gifs showing how it's moving around the ocean, and how certain sealife has been affected. (though these may have been from dubious sources, or they may not have been, ya just never know with me and I'm fucked if I can remember)
     
  19. T & P

    T & P |-o-| (-o-) |-o-|

    IIRC they have dumped some, but it seems they're now storing it, at least that used for the daily cooling.
     
  20. xes

    xes F.O.A.D

    Getting more and more potent with each recycle no doubt.
     
    TopCat likes this.
  21. elbows

    elbows WoeTimer

    Most of that comes from massive leaks into the sea from the first months of the disaster, and a few subsequent fuckups and failures to grasp the realities of groundwater etc on site. The water they've deliberately released into the sea is not contaminated to anything like that extent. Some legit animations will exist but these are likely to show theoretical movements of shit throughout the ocean based on various computer models. This sort of thing was used in a dubious way on the internet from time to time, probably most notably by those in the USA who wanted to hype the threat of the 'radiation arriving there'.

    They have various water decontamination facilities on site, which have had mixed results over the years. But they certainly do enough to ensure that the water doesnt get 'more and more potent' with each trip through the reactor basements. The biggest problem with water that they have is the sheer quantity of it that they have had to store on site. One reason there is so much water despite attempts to recycle it is that loads of groundwater has been entering reactor basements, which joins the water they pump in deliberately. Various attempts to fix this have been far from perfect and often have unintended consequences (eg when you stop groundwater travelling to certain parts of the site, it will go somewhere else/affect groundwater levels at different places around the site).

    They would like to reduce the amount of water they are pumping into reactors because the decay heat should be much less now that years have passed, but for PR more than scientific reasons they are being slow and cautious about this.

    Anyway, I havent had time to study the details of the massive radiation reading inside reactor 2 which reawakened this thread and is the real news here quite apart from the usual water issues. I shall study the detail now and report back in a bit.
     
    muscovyduck, SheilaNaGig and coley like this.
  22. xes

    xes F.O.A.D

    For the 100th time on this thread....thank you for a bit of balance and clarity.
     
    elbows likes this.
  23. elbows

    elbows WoeTimer

    My initial take on the reactor 2 stuff:

    The radiation measurement is very high indeed, and journalists at the press conference were somewhat confused and frustrated that such a large number compared to the ones they normally get was not given proper context or a full story/explanation they could run with. So we end up with headlines about 'radiation at highest level since disaster' that can be misleading.

    Its certainly the largest number I've seen in relation to radiation levels inside the reactor since the disaster, by a large margin. It does not mean that something new has happened though. It's the result of them actually getting a camera closer to the heart of reactor 2. They only made it to a vaguely similar part of the reactor a few times in the past, so this isnt an area where we have had continual radiation readings from in the past, and is not a case of a number we've been getting for years suddenly going off the charts. Its also an estimate that was based on how much interference there was to the images the camera was sending back, so there is quite a large margin for error due to this somewhat primitive methodology. Other large numbers from the same mission on the same day are an order of magnitude lower (eg 50 Sv/h and 20 Sv/h rather than 500 and something). Even so these are all large doses of radiation that have implications for equipment they plan to use for the next phase of this mission.

    I've been most interested in reactor 2 for years now for reasons I wont repeat again right now, but the information from these studies so far is still not enough to reach proper conclusions about the state of the reactor vessel, melted fuel location etc. Every time we learn a tiny bit more and this is certainly another step in the right direction, but the big number on its own doesnt give enough away. And there are setbacks nearly every time, eg discovering damage that affects their planned route for sending a more sophisticated robot/measuring device into the pedestal area directly below the reactor core.

    I will try to put the radiation reading in even greater context later if I can find the right numbers online.
     
    muscovyduck, SheilaNaGig and T & P like this.
  24. elbows

    elbows WoeTimer

    I found the number I was looking for.

    Take a particular type of spent nuclear fuel bundle and then let it cool for 10 years after it was last used in a reactor. Without any shielding, the dose rate on the inner surface of the waste package would be 270 Sv/h.

    The number the latest stories from reactor 2 involve is 530 Sv/h.

    There are many other details I coud drone on about to be more scientific with this comparison but this is just a basic attempt to indicate that such large numbers are not out of this world when it comes to getting up close and personal with nuclear fuel that had a normal life, let alone the messy remains of a reactor that suffered a meltdown.
     
    NoXion likes this.
  25. pk

    pk drink flounce rinse repeat

    Those gifs are often used as evidence for the dissipation of radiation - it's bollocks - they're just wave patterns from the March 2011 Tohoku earthquake. Conspiracy wankers are using it as "facts".
    That Fukushima Scare Picture is Fake
     
    NoXion likes this.
  26. elbows

    elbows WoeTimer

    Even some of the conspiracy sites point out the misuse of that particular image. There are a range of other images which are actually based on modelling of various radioactive things and how they are predicted to flow in that ocean, where the hype and distortion applied by scaremongers is slightly more subtle than 100% bullshit.
     
    pk likes this.
  27. 2hats

    2hats

    It's the highest reading that they've been able to establish (note, as above, +/-30% error as it was estimated from radiation noise in the imaging hardware). Radiation levels in the reactor pressure vessel (RPV) will almost certainly have been higher earlier but were not measured. These numbers are comparable to the reactor hall at Chernobyl post meltdown.

    The imaging suggests that corium has run down into the basement of the primary containment structure - recall the elephant's foot at CNPP. There's distortion and a 2m wide hole in one side of the pedestal grid structure (where previous images suggest some fuel may be located) below the pressure vessel - most likely where the corium (likely the source of the high readings) has flowed through it.
    [​IMG]
    TEPCO have produced a document illustrating the location relative to the RPV.

    The most recent muon tomography of reactor 2 was somewhat inconclusive but at the very least suggested fuel had either pooled towards the bottom of the RPV or (more likely) passed through into the containment.
    All three reactors are considered to be in cold shutdown since December 2011 (all three reactor pressure vessel and primary containment structure temperatures currently hovering around 14-22 degC).
     
    yield, T & P and elbows like this.
  28. elbows

    elbows WoeTimer

    I was quite gutted by how the results of that muon thing went, the resolution just wasnt good enough/too much noise.

    By contrast, that image you posted above is without doubt the most interesting one I've seen from inside any of the reactors to date. You are at least one TEPCO document ahead of where I was up to in regards this reactor 2 investigation mission, and its great to see them joining the images together like that. I've waited so long for them to get this far, watching the years fly by as they evaluated suitable penetrations into the containment vessel to send cameras/probes/robots through, and hit setbacks of various kinds along the way.

    Please stick around on this thread! There was a period some years ago where I mostly ended up talking to myself, and at other points I was the only one here digging into the nerdy documents. I discovered that I could make up for only reaching D grade A level physics many years ago, by spending vast amounts of time studying nearly all the Fukushima documents as they were released by the likes of TEPCO, METI, IAEA and following closely the right threads on a physics forum. I was lucky that I had loads of spare time in the first years following the disaster. But I am still uncomfortable in situations where I end up sounding like I know what I am talking about in without anyone else to correct me when I misspeak and add detail to areas where I skimp. And I have little doubt that you are better than me at laying out some scientific facts in a way that both uses the proper language and answers points without being so longwinded about it like I am.

    By the way I was always interested in reactor 2 for a number of reasons. It looks like they failed to vent it, so they never got to reduce reactor pressure in a somewhat controlled manner, or partially scrub some of the gas emissions by sending them through the water in the suppression pool and out of the stack. The building didnt explode, and a couple of photos that were released much later by TEPCO as part of a large collection showed an interesting cloud leaving the reactor 2 building (via the wall panel that came off) on the fateful morning of March 15th 2011. The weather conspired with this initial outburst from reactor 2 containment to cause a great chunk of the contamination of land, so in some ways this event and related images should have been just as big a deal as the explosions etc at the other reactors. But this part of the story seems to be fairly little known or discussed which only makes me go on about it more. March 15th tends to be remembered more widely for the same confused narrative that emerged in realtime on the day via somewhat dodgy TEPCO PR - they heard an 'explosion' early in the morning and because of a loss of suppression pool pressure reading, and then increased radiation readings on site, they thought there may have been an explosion in the suppression pool that caused containment to fail. There was a partial evacuation of staff. When they realised that the explosion bit was actually reactor 4 building, attention turned to the fuel pool there which further distracted from improving the narrative about what had happened to reactor 2 on that day. Which suited TEPCO at the time they were still in the stage of denial where they would still contradict themselves and mislead by talking about low chances of core damage and how containment was intact - yes the primary containment had not been blown to smithereens so it was intact in that sense. But really there was more than one form of evidence by then that containment was not airtight anymore at reactors 1, 2 or 3.
     
    yield and muscovyduck like this.
  29. elbows

    elbows WoeTimer

    Ha, in regards my steamy March 15th obsession, it seems TEPCO actually saw fit to provide a more straightforward narrative more along the lines of what I was going on about. When did they do this? December 2015.

     
    muscovyduck likes this.
  30. ska invita

    ska invita back on the other side

    elbows likes this.

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