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Japan

Fukushima Leak Traced To Overflow Tank Built On a Slope 76

AmiMoJo writes "The ongoing leak of radioactive wastewater at the Fukushima Daiichi nuclear plant has been traced to an overflow tank that was built on a slope. Because one side of the tank is lower than the other, water slops over the side when it is nearly full. TEPCO estimates that 430 litres of wastewater seeped outside the barrier around the tank and say some of this water may have flowed into the sea, about 200 meters away. They detected 200,000 becquerels per liter of beta ray-emitting radioactive substances in water pooled inside the barrier around the tank. The safety limit is 30 becquerels per liter. Officials say that a miscommunication with contractors led to the blunder."
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Fukushima Leak Traced To Overflow Tank Built On a Slope

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  • by Anonymous Coward

    No worries then

    • Re: (Score:3, Informative)

      by durrr ( 1316311 )

      It was 430 liters of wastewater with a comparatively low radiation level(0.2kBq, for nuclear medicine image studies you're counting mega-Bq and you're injecting it, for radionuclide therapy you're up in high and wild GBq numbers). So yes indeed no worries, really.

      Regarding the safety limit of 30 becquerel: that's two banana equivalent doses, meaning that a banana shake can exceed the safety limit. And 6 million bananas being equivalent to the total leaked value.

      • by durrr ( 1316311 )

        make that 0.2MBq, I was too busy thinking of BBQ to calculate properly

        • by Anonymous Coward

          Tokyo Electric Power Co, or Tepco, said the water that leaked contained 200,000 becquerels per litre of beta-emitting radioactive isotopes including strontium 90.

          So long, and you can keep your fish...

          • by Anonymous Coward

            Well, 90Sr would put the radiation in bad places, sure - but frankly, 86MBq of activity diluted in even a midsized pond is not really a big deal. The "safety limit", as shown above, is pretty much absurdly low.

            • 86MBq of activity diluted in even a midsized pond is not really a big deal.

              Have you ever heard of "bio-accumulation"? It's a process where e.g. a growing child drinks so much milk or eats so much fish, that part of the resulting Calcium intake can be used to grow her skeleton. Like the bits around her bone marrow [wikipedia.org]. Where the blood cells are made. For the rest of her life (well, there is probably some replacement; one Calcium atom is as good as any other).

              If you look at the periodic table, Sr is one below C

              • by delt0r ( 999393 )
                Plenty of the radioactivity from these sorts of pools comes from things that don't bio-accumulate. Of course some mite. But its as always, TFA is light on details.
          • by durrr ( 1316311 )

            Strontium is a bone-homing isotope, it's used in nuclear medicine to treat bone pain.

            Now I don't know about you, but I usually don't eat fishbones.

      • by mvdwege ( 243851 )

        It was 430 liters of wastewater in obviously incompetent hands. Given the rest of the blundering at Fukushima, that's scary.

        • Re:Ah (Score:4, Insightful)

          by Tailhook ( 98486 ) on Thursday October 03, 2013 @11:49AM (#45026405)

          scary

          430 liters is about 2x 55 gallon drums. It's nothing. The level of radioactivity is also rather low; 200kBq is literally 200,000 decay events per liter. A 7' long granite counter top radiates over 100kBq into your food.

          This is small and inconsequential. That it was even noticed is outstanding. The fact that the media has hysterical people like you in a lather is SOP.

          Don't worry; the hype has had the intended effect; the idiots are convinced TEPCO is destroying the planet. Yurts and Hobby Farms Now!!!11 herp derp.

          The fact that they're wasting resources to store water this clean is tragic. It should be pumped to the bottom of some ocean trench and the resources wasted storing it should be spent on useful work recovering the cores, spent fuel, etc. Instead, they're carpeting the area with water tanks in a monumentally stupid act of Nuclear Theater.

          • by mvdwege ( 243851 )

            The fact that you cannot read any further to notice that I was pointing out all the other TEPCO blunders suggests to me that your mother probably got a little bit too much radiation.

            To make it comprehensible to you: you're an idiot.

            • by Tailhook ( 98486 )

              all the other TEPCO blunders..

              ...are almost all the same sort of media hype designed to feed the prefered narrative of sheeple like you.

      • Re:Ah (Score:5, Insightful)

        by AmiMoJo ( 196126 ) * on Thursday October 03, 2013 @11:42AM (#45026323) Homepage Journal

        The limit is 30 becquerels per litre for beta radiation emissions. The potassium level in your body also remains fairly constant, so you will only have an elevated level for a few hours until it passes out. The stuff in this water can sit inside you indefinitely. Becquerels are an absolute measure of radiation, where as "banana equivalent dose" is supposed to be an "equivalent dose" based on how much harm it does the body and is not in any way directly comparable.

        Obviously the people who set these limits are not morons, they understand that it is perfectly safe to eat a banana or two. In any case, the level in this water is 200,000 becquerels per litre.

        I only wish I had the skill to draw an ASCII facepalm.

        • by CBravo ( 35450 )
          http://www.asciifacepalm.com/ [asciifacepalm.com]
        • by delt0r ( 999393 )

          Obviously the people who set these limits are not morons...

          No the people who set the limits are covering their ass more than making accurate recommendations, because you exceed these recommendations with some forms of medical diagnostics and treatments. Some places the background levels are above "recommended". So why do we live there?

          Simply FUD, radiation is scary and so is cancer. People will blame their cancer on the most outlandish things. So you cover your ass. And give stupid recommended levels that are often impractical but ignore natural sources.

          Oh an

  • by h4rr4r ( 612664 ) on Thursday October 03, 2013 @08:20AM (#45023995)

    So they can't even manage a level holding tank and they are allowed to keep managing this clean up?

    How is this level of incompetence possible?
    Does Japan lack the technology to build level storage tanks? Or to inscribe a maximum fill line in the tank otherwise?

    • Re: (Score:3, Insightful)

      by intermodal ( 534361 )

      It's not the lack of technology. It's the lack of geological stability. Fukushima is over 40 years old. The text provided on this subject here seems to convey a questionable assertion that it was intentionally built in its current position, but in a seismically active place like Japan, it is more likely that while the tank is built on a slope, it was built level. The shifting of the ground beneath the tank has probably caused the tank to lean a bit to one side.

      • by h4rr4r ( 612664 )

        So they have no surveyors?

        I would assume given the known lack of stability some inspections and resurveying would be done.

        • The Japanese always know best.

        • Re: (Score:3, Informative)

          by intermodal ( 534361 )

          I'm not sure you bothered to actually understand the situation before you made any of your posts. We're dealing with a facility that was heavily damaged years ago and you're trying to imply they have no surveyors? As TFA notes, they have been keeping the level lower due to this being a known issue. A rainstorm made it overflow.

          • by Anonymous Coward

            Neither did you, you fucking retard. A rainstorm didn't make the sloped tank overflow, contractors who put radioactive rain water into THE WRONG TANK made it overflow.

      • by khallow ( 566160 ) on Thursday October 03, 2013 @09:16AM (#45024613)
        It's worth remembering here that the tank might have been nice and level in early 2011.
        • Exactly. And that the area has, for the past couple years, been less than an ideal situation and is still in heavy disaster mitigation.

        • by MrL0G1C ( 867445 )

          How can you 'remember' something that's pure speculation?

          • by khallow ( 566160 )
            I'm speaking of the magnitude 9 earthquake. By their nature, earthquakes shift ground (since the energy is released by movement of large masses of earth) with magnitude 9 earthquakes doing a lot of shifting.
    • by Zeromous ( 668365 ) on Thursday October 03, 2013 @08:30AM (#45024089) Homepage

      When you consider how rapidly and the fact there are hundreds of tanks, it is entirely possible that one tank out of a few was built slightly sloped.
      The deviation must be quite small to only let out 430 litres slip out. 430 litres is literally a drop in the bucket when compared to the size of these tanks.

      It's great news they were able to track this down.

      • Re: (Score:1, Redundant)

        by intermodal ( 534361 )

        I think the American audience is having a hard time understanding that this isn't terribly different from a kiddie-pool worth of water.

      • FTFS:

        TEPCO estimates that 430 litres of wastewater seeped outside the barrier around the tank

        430 litres isn't what leaked out of the tank. 430 litres is what they estimate might have been the amount that got through the failsafe; that is, the barrier around the tank.
        Industrial holding tanks in virtually any western country that pays anything more than lip service to safety are required to have safety berms built around them, to form a barrier that prevents extreme spillage in case of a disaster like a ruptured tank. The berm is usually large enough to hold the entire contents of the tank.
        I'm

        • If it's close to grade (ie not obviously leaning), let's assume 5deg, it's probably not as much as you suggest since logically does not indicate the berms were filled. Why would they filled if the leak was caused by a bad grade?

          We could easily estimate, but I lack dimensions of the cylinders. I looked casually and found nothing.

          • If it's close to grade (ie not obviously leaning), let's assume 5deg, it's probably not as much as you suggest since logically does not indicate the berms were filled. Why would they filled if the leak was caused by a bad grade?

            We could easily estimate, but I lack dimensions of the cylinders. I looked casually and found nothing.

            Because if the tank was at 5deg, then the berm is going to be about the same. In order for the contents to leak out of the berm, it's going to need to be almost to the top, otherwise it wouldn't pour over.

      • The deviation must be quite small to only let out 430 litres slip out.

        More to the point: why were these tanks designed with open (or for all practical purposes open) tops?? If that minimum amount can slop out just due to grade, how much are they losing just to freaking evaporation?

    • by AmiMoJo ( 196126 ) * on Thursday October 03, 2013 @08:40AM (#45024223) Homepage Journal

      They knew the tank was not level, and were careful not to overfill it. The problem is that this was not communicated to the contractors who then did overfill it.

    • by durrr ( 1316311 )

      They're not just having one storage tank in the area: go look at http://msnbcmedia.msn.com/i/reuters/2013-05-15t210949z_1_cbre94e1msm00_rtroptp_3_japan-power-deregulation.jpg [msn.com]
      That's from march this year.

  • by sl4shd0rk ( 755837 )

    430 liters.... LITERS. This is about two 50 gallon drums. The only reason this is making news is because TEPCO's overall problem with radioactive water gushing into the ocean is as catastrophic as BP's DW Horizon - possibly worse -- but they won't admit it.

    • 113.6 US liquid gallons to be more precise and so you are going to have some overflow in those drums, it never ends. But I could be wrong as you may have been referring to imperial gallons.
      It is like a Cat in The Hat adventure. litre/liter . The summary seems to have been done by somebody who wanted to please everybody as they use both.
      I agree with what I thought you implied: How is this important compared to all the other stuff that happened?
      In other news, "Student reports falling asleep in park and
    • by khallow ( 566160 )
      I imagine there wasn't much if any radioactive water gushing into the Gulf of Mexico from Deepwater Horizon, so yes, it is more "catastrophic" in that hysterically overblown sense.
      • I question if gazillions of gallons of oil gushing into the ocean all at once is more or less bad than a little plutonium. Plutonium is pretty fucking toxic. Uranium... not so much. I mean it's bad, but it's not plutonium-bad. But that's a lot of oil.

        • by khallow ( 566160 ) on Thursday October 03, 2013 @10:28AM (#45025471)

          I question if gazillions of gallons of oil gushing into the ocean all at once is more or less bad than a little plutonium.

          I go with more bad.

          Plutonium is pretty fucking toxic.

          If you breathe it in under ideal conditions. Most sea life doesn't have lungs, the plutonium would all be chemically bounded up as salts or other compounds, the whole mess would be greatly diluted, and there wasn't much in the way of plutonium anyway - they're far more worried about radioactive isotopes of cesium or strontium.

    • What's funny here is that this is just beta-ray radiation, which is more penetrating ionizing radiation than alpha-ray radiation... made of electrons.

      In short: the best way to handle this is to slowly dump it into the sea. Not kidding. That would solve the problem. the impact would be uh... ... nothing. You'd have a few extra electrons here and there and that's it; I mean yeah you don't want to just unload all of this in one spot in one shot, it would be kind of shitty there for a few hours (possibl

  • by Anonymous Coward

    One side was built using cm and the other one using inches

  • by MickyTheIdiot ( 1032226 ) on Thursday October 03, 2013 @08:45AM (#45024279) Homepage Journal

    They should have hired Hank Hill to put it in. The could have told him it was a septic tank. It would have been perfect and had a lawn over it.

  • by Anonymous Coward

    It's called "OVERFLOW" tank, hello!

  • now fix it.

  • Vanguely reminiscent of Titanic's "watertight" compartments, which were watertight at the SIDES, but open at the TOP. I believe it was "unsinkable" in some technical understanding of the word. That is, a localized hull breach that filled only one compartment would not have sunk the ship. But water could spill from one compartment to another when the ship was tilted, and thus the entry of water was not confined to the compartments where the leak was. Or something like that...

    • Vanguely reminiscent of Titanic's "watertight" compartments, which were watertight at the SIDES, but open at the TOP.

      That is a reasonable design when you look at the tradeoffs. Titantic had 16 compartments, and could withstand up to four being breached at either the bow or stern, and even more could be breached amidship (where they would not cause much tilt). The problem is that five were breached, all at the bow. This was a "worst case" scenario. Even then, they may have been able to save the ship if they reacted quickly, by flooding the last compartment aft. That would have helped to balance the ship. But by the t

      • by coolmoose25 ( 1057210 ) on Thursday October 03, 2013 @11:48AM (#45026395)
        IIRC, there was a show I watched on the sinking that took the premise of counterflooding and tested it. They built a scale model, and they were able to fairly accurately recreate the actual sinking, without counterflooding. They then tested what would have happened if they had counterflooded the ship to maintain its trim. Counterintuitively, the ship actually sank faster with counterflooding. I think they explained it by showing that while the out of trim condition contributed to the "ice cube tray" phenomenon that finally sank the ship, the counterflooding would not stop that. It wouldn't even slow it down. With the flooding in the bow from the strike of the glacier, combined with the negative buoyancy of the counterflooded aft, the ship was so low in the water at that point, it allowed the compartments aft of the comprised compartments to fill the adjacent compartments even faster, while the ship was now that much closer to sinking due to the negative buoyancy of the counterflooded aft. They also explored the stability of the ship in such a condition. They found that the ship became unstable laterally, and thus it would have risked a capsize as well. Overall, it was better not to counterflood.
  • 1) The current problems are just happening while the earth around is half way stable and not shaking too much. But what will happen if a half way decent earthquake is hitting the area of Fukushima? What will then happen to all those water tanks which seem already now to have bigger problems on a regular basis? What will happen to all the other sensitive parts of the nuclear plant whose structure is already badly damaged from the previous tsunami.

    2) How many decades will the damaged poweplant still have to s

  • Did the same people design this tank that couldn't handle the English-to-Metric conversion problem at NASA?
  • -Boom!
  • Officials say that a miscommunication with contractors led to the blunder.

    Like what? They have different definitions of "level" and "plumb?"

    Because one side of the tank is lower than the other, water slops over the side when it is nearly full.

    Why would anyone *want* build a containment tank like that? This could have been avoided if someone had simply said, "Are you sure? Because this is stupid." Also, the phrase "nearly full" would obviously mean something different on opposite sides of the tank - another clue that something was wrong...

  • Contractors are a nifty feature of modern corporations. When shit hits the fan, the big firm can say it did nothing wrong, it was the contractor fault. On the other hand, the contractor does not care, PR is not its problem.

    IMO the big firm should be fully liable, including in PR area. We should never hear about "the contractor fault". They chose to outsource, now if the work was badly done, it is their problem, they just have to sue the contractor for the loss.

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