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Japan Power

30 Years To Clean Up Fukushima Dai-Ichi 342

0WaitState writes "Damaged reactors at the crippled Fukushima Dai-Ichi nuclear plant may take three decades to decommission and cost operator Tokyo Electric Power Co. more than 1 trillion yen ($12 billion), engineers and analysts said. Relatedly, Japanese officials and power plant operators are now working on the problems involved with disposing of 55,000 tons of radioactive water. '... international law forbids Japan from dumping contaminated water into the ocean if there are viable technical solutions available later. So the plant operator is considering bringing in barges and tanks, including a so-called megafloat that can hold about 9.5 megalitres. Yet even using barges and tanks to handle the water temporarily creates a future problem of how to dispose of the contaminated vessels.'" Yesterday's 7.1 aftershock caused brief power losses at three other nuclear facilities, and small volumes of contaminated water spilled, but no significant radiation leakage occurred before the problems were resolved.
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30 Years To Clean Up Fukushima Dai-Ichi

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  • by ackthpt ( 218170 ) on Friday April 08, 2011 @12:19PM (#35759104) Homepage Journal

    Have they considered putting it in cans and selling it at gas stations with a big glowing F on it?

    Fukushima - For Radiant Health! It'll make a Monster out of you!

    marketing has an answer for everything!

    • by Ruie ( 30480 ) on Friday April 08, 2011 @12:25PM (#35759222) Homepage

      Have they considered putting it in cans and selling it at gas stations with a big glowing F on it?

      Fukushima - For Radiant Health! It'll make a Monster out of you!

      marketing has an answer for everything!

      This has been tried before []...

    • by Hatta ( 162192 )

      What exactly is "radioactive water"? Is it water with radioactive solutes in it? Or is it tritiated water? If it's the former, then they could just evaporate it and deal with the precipitate as solid waste. If it's the latter, it's not a big worry anyway, tritium emissions can't even get through a sheet of paper.

      • by Anonymous Coward on Friday April 08, 2011 @12:43PM (#35759480)

        tritium emissions can't even get through a sheet of paper

        Those are the dangerous emissions. They don't get through paper because they loose all their energy damaging it, which does not much for paper since it is already dead. Its the reason why the protective gear used near nuclear accidents is so thin, its enough to keep the alpha radiation from reaching your body, once ingested however there is nothing between it and your vulnerable cells.

        • by Hatta ( 162192 )

          How about they free the tritium via electrolysis, making 3H2 gas. Then use the tritium gas to hydrogenate something that will end up as a solid that you can contain and bury.

          • Are you aware how radioactive tritium is? The amount involved is actually tiny. Which means you would have to electrolyse almost all the water to get it out. Deuterium in contrast is relatively common, which is why it is possible to get D2O using electrolysis. Incidentally the best thing to hydrogenate is solid uranium.

            For years the British Government demanded that waste tritium be discharged as tritiated water...which is the worst possible solution. As a gas, you can collect it relatively easily. Once in w

            • by HungryHobo ( 1314109 ) on Friday April 08, 2011 @01:11PM (#35759874)

              just to do the math :4.4 kilowatt-hours of electricity to split one litre of water with electrolysis.

              so for 55000 tons of water it would take about
              242000 MW hours of electricity to split it all.

              Not a show stopper but quite a lot.pretty much the full output of a large power plant for a few weeks.

              just thinking a bit outside the box: how reasonable would just adding some kind of gelling agent to it so you end up with a tank full of 55000 tons of strawberry flavoured radioactive jelly?

              far less risk of a leak and a hundred or so years down the line it's pretty much safe again.

      • " can't even get through a sheet of paper."

        until you drink it...

        I'm very much in favor of nuclear power, even after the recent event but with it's 12 year half life(making it a far far more potent source than stuff with 20K year half lives but a far longer term problem than the stuff with a half life of days ) and the fact that it's part of water and easily mixed with drinking water and readily absorbed into the body it is a fairly dangerous substance.

        I'd be interested how concentrated that 55K tons is. If

      • by Zeio ( 325157 ) on Friday April 08, 2011 @12:52PM (#35759606)

        Alpha particles can be breathed and actually is the most ionizing of all the ionizing radiation.

        Alpha particles are extremely dangerous but are not penetrating.

        The worst vector is to have an alpha emitter embedded in living tissue.

        You must understand radiation exposure is not the same thing as exposure to hot particles or hot particles embedded in vivo.

        There is a terrible misunderstanding going on. Sure, you could eat dinner next to a solid block of plutonium if its not critical its just a metal brock that emits some radiation. There used to be uranium paints and glazes used on cookware. Atomized and superheated fission products or fission products in salts and compounds embedded in vivo is a bloody mess. Its porrly understood and you can't use "x-rays, cosmic rays, plane flights" and trash like that to compare. The rays aren't that dangerous. The hot particles are very very dangerous because they can become part of your own biology and emit, even at low levels, inside your body.

        So much for your sheet of paper. If that was the cause, Radon wouldn't be remediated and people would just enjoy sniffing alpha particles.

        • by HungryHobo ( 1314109 ) on Friday April 08, 2011 @01:01PM (#35759736)

          yes, the GP is probably what people are talking about when they accuse the pro-nuclear side of being cavalier about radiation.

          Plutonium with it's 20K half life is mainly dangerous as a heavy metal, iodine-131 with it's (if I'm remembering this correctly ) 8 day half life is at least gone after a few months.

          but that 12 year half life is a pretty bad one, too long to expect it to be gone in a reasonable time but short enough to be a really nasty source of radiation.

          Storing it shouldn't be too much of a problem at least, it's not a source of neutron radiation so it shouldn't leave it's container radioactive and since it's an alpha emitter a plain old water tank is good enough to shield people outside from the radiation but it's a bad one when it escapes into the environment and gets drunk by people.

          • Sorry, but the toxicity of Pu is mainly radiotoxicity. The chemical heavy metal toxicity is quite negligible compared to that. No problem handling a subcritical solid sphere of Pu - but as soon as you get particulate matter or soluble Pu ions, you want to stay the heck away from it. It has a long biological halflife and tends to get you cancer real quick when in the body.
        • Sure, you could eat dinner next to a solid block of plutonium if its not critical its just a metal brock that emits some radiation.

          I see what you did there, and I rove it so much.

        • Indeed. You can't stress that enough. The part of labwork I hated most was working with Tritium-labels. Sure, that plastic shield holds back all the alphas, but stuff gets aerosolized and that is not particular fun. Labeled nucleotides are the best fun of all - ingest the shit and it gets incorporated straight up into your DNA. Hell yeah.
          • by blair1q ( 305137 )

            Labeled nucleotides

            Those couldn't emit alpha particles. Changing the atomic number of an atom that's part of a DNA strand would be extremely bad. Unless that's the experiment you're conducting.

            So you're talking about neutron emitters? Isotopes with the correct number of protons but (temporarily) extra neutrons?

        • Tritium doesn't have a massive enough nucleus to emit alpha particles. It transforms to Helium-3 via beta decay. It's pitiful that even on Slashdot, the thread could get to this depth (and even deeper []) without someone noticing this.

      • by slew ( 2918 )

        Sadly, radioactive water is mostly water that has dissolved or partially suspended radionuclides and compounds formed with radionuclides. The problem with evaporation is that although it removes the most of the solids, any dissolved gasses are generally carried along with the water vapor. As a simplistic example of this, consider carbonated water. The dissolved carbon dioxide gas would pretty much evaporate with the water.

        If you look at few of decay products of the fuel in the reactor you might see the p

      • If it's the former, then they could just evaporate it and deal with the precipitate as solid waste.

        If the entire stated power (4400 MW) of the late Fukushima 2 is converted with no loss into the chemical energy required to evaporate 55000 tons of water, then it will take (2257 [J/g] * 55000000000 [g] / 4400000000 [J/s] / 60 / 60) = 7.8, almost 8 hours to boil it all. Now, how much power can they realistically jam into the heaters on board of a tanker at sea? Probably orders of magnitude less than that. 10000, 100000 times less? So they have a bit of a problem doing it this way.

      • But IIRC you do not want to drink tritiated water both because tritium has the wrong chemistry and because you get 4\pi radiation from the decay so the energy will be dissipated in your cells and soft tissue. Not getting through a sheet of paper or your skin from the outside is one thing, but if it starts out inside of you the "skin" that stops it can be your DNA, fired from a water molecule inside the same cell. Lessee... [], yup, that's right.

      • mostly solutes and precipitates, maybe a trace of tritium or ditritium oxide and diduterium oxide

    • I'm kind of glad nobody else thought of the easiest, and to me and my love for Cascadia, least favorite solution: Barge it across the ocean and up the Columbia to irrigate the already radioactive but potentially biologically useful and unique Hanford Reservation (there have been two unique species found there in the last 40 years, both of whom could use a bit more ground cover, even if it's radioactive grass).

      • by blair1q ( 305137 )

        It's possible. We already do that sort of thing overland with nuclear waste.

        England ships its waste to Ireland. [].

        I wonder if anyone's taken a look at that massively deep trench a hundred km off the Japanese coast that's slowly but blatantly folding in on itself, and thought of planting it all down there to be reabsorbed by the planet.

        There are probably issues with currents and whatnot, but it's an idea.

    • Fuka-Cola Quantum?
    • Just mix with cola!

  • by Anonymous Coward

    The weird thing is that the Pacific Ocean is so big that they could probably pump it into the depths and the radiation increase would be completely irrelevant.

    Not the most responsible-sounding thing to do and I'm not advocating it, just saying that it's weird how just dumping it into the middle of the largest ocean available would probably end up hurting fewer people than any competing kind of disposal.

  • The solution to pollution is dilution.

    That's what the miners tell me, anyway.

    • Re: (Score:2, Informative)

      by ackthpt ( 218170 )

      The solution to pollution is dilution.

      That's what the miners tell me, anyway.

      A mining engineer once explained the difference between Hazardous Waste and Toxic Waste -

      Hazardous means harmful in high concentration, e.g. grain alcohol is fairly harmless below 5% by volume, but fairly hazardous above 90% by volume.

      Toxic means harmful in any concentration. Plutonium is the most toxic substance known - even one atom will be harmful, even if not readily apparent.

      • Re:oblig (Score:4, Interesting)

        by locofungus ( 179280 ) on Friday April 08, 2011 @12:56PM (#35759670)

        Plutonium is the most toxic substance known - even one atom will be harmful, even if not readily apparent.

        Except that the facts don't agree with you.

        Plutonium is a lot less toxic than something like dimethyl mercury.

        It's definitely not something you should eat or inhale the dust but it's no more toxic than a lot of other substances, many of which are contact poisons.


        • Well, dimethyl mercury is probably Nr. 1 on my list of stuff I will not work with in a lab, ever. No Sir, find someone else to handle that shit. Outright scary stuff. Plutonium, while indeed a lot less toxic, is not far beyond though. The chemical toxicity doesn't concern me there, but ingestion of an alpha emitter with a long biological half-life is not on my agenda, either :P
          • Plutonium is still irrelevant when discussing the most poisonous substance known. Chemical toxicity is smaller than the worst poisons, and when it comes to radiotoxicity it has a huge half-life compared to really unstable nuclei which have a half-life on the order of 10^-22 seconds. And even those should be nowhere close to anti-matter in toxicity.

            If you think this is an absurd comparison since no one will ever encounter these substances then I think that's fair enough. In that case we can continue to Polon

      • Plutonium is the most toxic substance known - even one atom will be harmful

        What a load of bullshit.
        Please mod this post down!

      • If you consumed raw, non-fissile uranium or plutonium, it would be passed through your system as solid waste before it could cause any real damage by irradiation. Even if a few particles stuck in your system, they are not radioactive enough in their natural state to be harmful to you. You would probably succumb to heavy metal poisoning before you experienced any radiation poisoning.

        If it is instead a byproduct of fission, or a substance which is analogous to something your body readily absorbs, such as Iodi

      • Plutonium is the most toxic substance known - even one atom will be harmful, even if not readily apparent.

        Even though I'm not anywhere near an expert when it comes to nuclear physics, elemental decay, etc, that still seems like BS to me. It emits a single alpha particle and now it is no longer Plutonium. I just can't see how that can be so dangerous. But, I was willing to concede that, due to my lack of expertise, there may be something here I don't fully understand. So I went to look it up:

        Plutonium is more dangerous when inhaled than when ingested. The risk of lung cancer increases once the total dose equivalent of inhaled radiation exceeds 400 mSv.[91] The U.S. Department of Energy estimates that the lifetime cancer risk for inhaling 5,000 plutonium particles, each about 3 microns wide, to be 1% over the background U.S. average.[92] Ingestion or inhalation of large amounts may cause acute radiation poisoning and death; no human is known to have died because of inhaling or ingesting plutonium, and many people have measurable amounts of plutonium in their bodies.[77]

        I'm not sure how many atoms of plutonium it takes to make a 3 micron wide particle. A quick search looks like Pu is approx

  • Filtration (Score:3, Informative)

    by EdZ ( 755139 ) on Friday April 08, 2011 @12:23PM (#35759184)
    Wait a few weeks for the Iodine to decay, filter out the Ceasium and any inert heavy metals that might have been picked up. Pump now pure water into sea.
    As for the storage barges: they're only intending to store lightly contaminated water in them (to make room in the internal tanks for more heavily irradiated water), so irradiation from decay will be minimal. A good rinse should be sufficient to clean them of any radionuclides hanging about.
    • Wait a few weeks for the Iodine to decay, filter out the Ceasium and any inert heavy metals that might have been picked up. Pump now pure water into sea.

      If it were that easy, nobody would be worried.

      (Protip: You can't filter out elemts dissolved in water.)

      A good rinse should be sufficient to clean them of any radionuclides hanging about.

      Thereby creating *more* contaminated water to handle.

  • Halflife? (Score:4, Interesting)

    by RingDev ( 879105 ) on Friday April 08, 2011 @12:25PM (#35759216) Homepage Journal

    IANANS (I am not a nuclear scientist), but isn't this issue largely controlled by the radioactive material's halflife? If what ever it is that is causing this issue has decayed to the point that it poses no significant risk after 10 years, would the containment vessel be any more radiated?


    • Re: (Score:2, Informative)

      by Anonymous Coward

      Unfortunately, while the radioactive iodine has a half-life of only eight days or so, the radioactive cesium has a half-live of over thirty years. Radioactive cesium isn't as harmful as iodine (it doesn't accumulate in the thyroid gland forever) but it is water-soluble, unlike (for example) a noble gas, and will increase the risk of cancer if it makes its way into the water supply or the fishes' food chain or what have you.

      • by RingDev ( 879105 )

        So if it is cesium in the water that is causing this issue, is it possible to either filter or distill the cesium out?


        • And they could use it to build very accurate clocks and watches, with natural glow-in-the-dark faces!

        • Filtering is out, because not all of it is particulate, but rather in solution. Distillation would work, though. Personally, I'd opt for ion exchange - would probably get the highest throughput. In either case, you will have to set up a plant for it. That will take time. Properly treating the water will take a lot of time too, as you don't want to accumulate so much material on your ion exchange resin that you can't handle it safely, so you will go through a lot of resin, do a lot of replacement. Same with
  • by Anonymous Coward

    Is 30 years a long time? Just wondering.

    Could someone put 30 years into perspective for me? How long does it take to clean up the byproducts from a coal plant, even given routine conditions where there is no earthquake or tsunami or explosion? If a coal plant was decommissioned in 1981, is it reasonable for me to assume that all its poisons are gone now?

    • by hawguy ( 1600213 ) on Friday April 08, 2011 @12:35PM (#35759384)

      Could someone put 30 years into perspective for me?

      No problem, I can put it into units that most Slashdot readers are familiar with.

      The Library of Congress is 211 years old, so 30 years is around .14 Library of Congresses.

      In comparison, a 2TB hard drive is around .2 Library of Congresses (printed material only).

      So, in conclusion, Fukushima's cleanup is less than one 2 TB hard drive.

      • That is one of the best LoC measurments I have ever seen! Kudos to you good sir!


      • Looks like I picked the wrong week to give up mod points.

        Very well played

      • The Library of Congress is 211 years old, so 30 years is around .14 Library of Congresses.

        In comparison, a 2TB hard drive is around .2 Library of Congresses (printed material only).

        So, in conclusion, Fukushima's cleanup is less than one 2 TB hard drive.

        Each slashdotter needs to start sending one old drive, and let distributed computing solve this problem in parallel 2,000,000 times faster than those poor sods in the protective suits.

        GO GO GO!!!

      • by blair1q ( 305137 )

        Did you get that hard drive from China? Mine holds 20 TB easy.

    • by hedwards ( 940851 ) on Friday April 08, 2011 @12:37PM (#35759404)

      The major difference is containment. Hazmat equipment for dealing with chemical spills is much more effective than the gear for dealing with radiation. It does depend which type of particles you're dealing with, but some of them are pretty nasty and can penetrate thick concrete walls.

      Nuclear clean up can take a really long time, just because the exposure is harder to manage and the steps involve more complicated. The world famous Hanford Site was last shut down in the late 80s, and we're still barely into the process of getting the site cleaned up. Granted it was established in the 40s for the purposes of creating nuclear weapons, but the site itself is still a mess and it's likely to still be a mess in 30 years at the rate things are going.

      Hanford clean up []

    • by siddesu ( 698447 ) on Friday April 08, 2011 @01:10PM (#35759846)

      I have a small property in a city in a small, ex-communist country that had a large (4 boilers, 4 turbines) coal plant in operation until about 1992. Since I go there from time to time, I can tell you pretty well how things went year by year.

      When operation stopped (for various reasons, mostly lack of money and lack of cheap fuel after the collapse of COMECON), the plant was left to the elements. Until about 2002, the plant became a scrap iron mine -- the gypsies from the neighboring villages would come in, break shit up, cut out the metal and move it away. When iron became scarcer, they started to break up the buildings, piece by piece, extract window frames, nails, etc. Around 2002, the only thing that remained was a pile of rubble, mostly broken bricks, and a smokestack.

      Surprisingly, the rubble started to disappear about 2003. I have no idea what has happened to it, but the mountain of broken bricks has halved by 2004, and almost gone by 2005. In 2006, the smokestack was pronounced a hazard, and a demolition grant was obtained from the government to destroy it. It became a small brick peak where the mountain used to be, but in another year those bricks were gone too.

      In the end, the city government got an EU grant for "eco tourism area", spent a small amount of money (in the one to two million euros range) on removing the few remaining concrete blocks and , had some Dutch organization test the soil. Since they got a certification that allowed them to cultivate organic vegetables on part of the territory, I assume it wasn't very polluted.

      So, in less than 20 years, the plant was gone completely.

      Is this what you wanted to hear?

      • Your story is interesting but I don't think it directly addresses the core question.

        Coal plants spew poisonous/radioactive waste over a fairly large area of the life of its operation. The older the plant, the worse it tends to be. So while the plant my be gone, the question remains, how much of the surrounding area is still poisonous and/or radiative?

        It doesn't sound like you know if the issue has been explored at that site or not. Even worse, if anyone is growing vegetables in the region, it can potential

    • Could someone put 30 years into perspective for me?

      30 years is long enough for Britney Spears to be born, grow up, and start a "music" career.

    • by jd ( 1658 )

      To put this in one perspective, the Industrial Revolution's heavy use of coal resulted in the entire Peak District being contaminated by metal-eating bacteria which are causing massive destruction and will continue to do so for centuries. The Irish Sea is the most radioactive in the world because of dumping of uncontained plutonium in the ocean and will continue to be for tens of millenia. In this sense, 30 years is nothing.

      To put it in a different perspective, using the same example: These same examples of

  • Nuclear economics (Score:4, Insightful)

    by mspohr ( 589790 ) on Friday April 08, 2011 @12:33PM (#35759354)
    Nuclear power has never been economic. It has only existed because of massive government subsidies (research, fuel, insurance, waste disposal, etc.). Also, unlike other technologies, the cost per watt of installed power keeps increasing, not decreasing. This latest disaster will only make it more expensive. Already wind and solar are cheaper per watt of installed power without all the nasty nuclear uncertainties. I doubt that you will see any new nuclear plants in the US solely because of the cost. No sane investor would fund a nuclear power plant now.

    I rather think that this is a good thing.

    • by wiredog ( 43288 ) on Friday April 08, 2011 @12:41PM (#35759454) Journal

      Consider the costs of coal. The radiological problem of the coal ash. The excess CO2. That cost, right there, is not being accounted for.

    • by Anonymous Coward
      Nuclear power has never been economic

      Citation needed. Oh and please define 'economic'.
    • by Xelios ( 822510 )
      Wind and solar provide variable power. Which is fine so long as you have sources of continuous power running in the background. There's really only a few possibilities for this backbone; fossil fuels, hydro, geothermal and nuclear. Hydro and geothermal are very location-sensitive, fossil fuels are running out and create a lot of pollution, nuclear is expensive. But you gotta pick one, so which will it be?

      Thanks to public perception, we're still picking fossil fuels, but one day relatively soon nuclear wi
      • Wind and solar provide stochastic, but predictable power, which, over the grid averages out and can indeed provide baseload. If you go solar thermal, you got a large buffer in your molten salt reservoir, so you get even less stochastic influence.
      • You can cheaply store energy in molten salt [] for a week. That, combined with an upgraded, national power grid to distribute power beyond regional weather patterns, should allow us to replace most of the base load with variable sources.

        Some of the rest could be filled in with hydro... a reservoir is a huge energy store, and more reliance on local solar/wind would let us keep the reservoirs topped up for when we need them.

        Then coal would be a last resort. After all, nature can absorb CO2, we don't need t

      • Nuclear is getting more expensive while wind and solar costs keep dropping. You have something backwards.
        Oh and peak uranium is around the corner too - expected around 2030.

      • Wind and solar provide variable power. Which is fine so long as you have sources of continuous power running in the background.

        I'm sure I'll be annihilated for this question, but isn't the wind always blowing somewhere in the U.S., or at least in the world? It seems that a well-designed mechanism of quickly swapping sources of electricity from strategically located wind farms across the country could provide "continuous" power. If the wind isn't always blowing, then there might always be currents/tidal waves on our ocean coasts. Couple that with solar and hydro, one could fathom a nice electricity backbone. Hot-swapping technology

    • I think most people would agree that if there is a better, cleaner solution for power generation than nuclear, then we should use it.

      But from where I sit in Japan, experiencing rolling blackouts, darkened train stations, closed shops, and missing food items, that source of electricity absolutely needs to replace the millions of kilowatts that it takes to run an operate a modern society currently provided by nuclear energy. The whole of eastern Japan is in conservation mode and yet they are still telling us

    • by Animats ( 122034 )

      Nuclear power has never been economic.

      If you charge Gulf War I, Iraq, and Afghanistan to the cost of oil, nuclear looks a lot cheaper.

      Crude oil is at $112/bbl today. It's not likely to spend much time below $100 ever again.

    • by blair1q ( 305137 )

      Coal kills 10,000 people a year.

      Now tell me nuclear power isn't economical.

  • Whats wrong with saying 9.5 million litres? Why use an obscure term like megalitres? Is it just because americans don't get the metric system?

    • Why even use liters at that point... cubic meters is much more descriptive... or Tons if you must!

    • 9.5ML is an SI unit. The 55 kilotons should be expressed as 55ML (using water's density=1000 kg/m^3). So we can see at a glance that they need 6 tankers at the moment.

      We avoid exponents this way. Or the short scale/long scale "billion issue".

    • I did stop to wonder how much a megalitre was :)
    • by Mashiki ( 184564 )

      Megalitres is an obscure term? I suppose if you're american. Pretty much every other country that uses SI or a form of SI along side imperial(Canada), uses it for large fluid volumes.

      • Megalitres is an obscure term? I suppose if you're american.

        We think of volume primarily in terms of Budweiser cans. Tallboys mainly.

  • I'm assuming... (Score:4, Insightful)

    by fuzzyfuzzyfungus ( 1223518 ) on Friday April 08, 2011 @12:41PM (#35759462) Journal
    I'm assuming that the eventual plan will involve some sort of distillation or RO process: 55,000 tons of water is not something you would want to have to safely entomb somewhere; but the actual volume of long-term nasties must be fairly small(worst case, it could not be greater than the volume of the fuel on site, and any materials that it has been in long term contact with for a sufficient time to render them radioactive, and it doesn't appear to be worst case).

    While not terribly cheap, the technology for separating dissolved compounds from water(to fairly extreme degrees of purity, in the case of water for lab/analytic use) is very much off-the-shelf. Similarly, gross screening of a volume of treated water for radioactives should be doable with a Geiger counter, and fine screening should be within the realm of any decently equipped testing laboratory.

    It isn't going to be cheap, and the end result will be a small pile of serious unpleasantness and a rather larger one of equipment that isn't worth decontaminating; but it doesn't seem like a fundamentally hard problem.
    • by Animats ( 122034 ) on Friday April 08, 2011 @01:35PM (#35760264) Homepage

      While not terribly cheap, the technology for separating dissolved compounds from water(to fairly extreme degrees of purity, in the case of water for lab/analytic use) is very much off-the-shelf.

      Right. That was done at Three Mile Island. Bear in mind that you can't make water itself radioactive; hydrogen and oxygen don't have any radioactive isotopes with long half-lives. (The longest, 15O has a half-life of 122 seconds, so it's gone within an hour.) All the radioactivity is in dissolved solids. So the process looks a lot like desalinization - the water is forced through membranes that catch all the solids. Eventually, you have dry salts, which you put in casks and bury in some desert or hard-rock cave.

      That's the easy part of the problem, though. Remember that the reactor buildings are wrecked from the hydrogen explosions. All the fuel rods in the spent fuel pools have to be carefully moved to some other location, probably newly built spent fuel pools nearby. In 3-5 years, they'll have decayed enough for dry storage, and they'll be put into casks. They can then be moved off site.

      This leaves the reactors themselves. Units 1,2, and 3 still haven't reached cold shutdown. Until that's achieved, cleanup can't even start. The situation isn't even close to safe until all three reactors are in cold shutdown, not leaking, and have redundant cooling. Look at the status reports at the Japan Industrial Atomic Forum []. Until all the red squares turn yellow, there's a sizable risk of things getting worse.

      Decommissioning the damaged reactors will be really tough. They're too damaged to de-fuel, and they need constant cooling, so they can't just be encased in steel and concrete. I don't know what will be done.

      This is much, much worse than Three Mile Island. At TMI, the control room was up and running through the whole episode, they reached cold shutdown in a few days, they never had an explosion, and radioactivity was confined to the containment vessel.

    • I wonder if it would be feasible to use one of the intact reactors on the site (unit 5 or 6) to boil the water.

  • Buy a barge, fill it up, float it to the middle of the Pacific and scuttle the ship. I think the international community can make an exception this time, all things considered. Other 'viable technical solutions' carry their own risk, and those risks will be continuous over the next 5 years or more, near population centers instead of out in the middle of the ocean.
    • Not like I have a solution to pose, but given that air currents in a hurricane move tons of cloud masses through thousands of kilometers, what's to prevent ocean currents from doing the same and poisoning our fish?

      Peeing in the pool does not just affect the pee-er's area. Remember the Big Gulf Oil Spill of 2010?

  • Seems surprisingly cheap to me for what is essentially the #1 or 2 largest nuclear disaster of all time.
  • by Kyusaku Natsume ( 1098 ) on Friday April 08, 2011 @02:19PM (#35760964)

    TEPCO has put back online units 3, 2 and 5. From their press release: []

    -Kashima Thermal Power Station Units 6: shutdown due to the earthquake
    -Kashima Thermal Power Station: Units 2 resumed generating power at
      5:45 pm April 7th.
    -Kashima Thermal Power Station: Units 5 resumed generating power at
      9:27 am April 8th.

    Yesterday they put online unit 3, I'm impressed that they managed to put those units online in such a short time even with the ground still shaking.

    Also, they put forward a plan to reinforce Kashiwazaki-Kariwa NPS, the largest in the world, in accordance with the new, upgraded regulations for the operation of NPS in Japan, in [] and graphics []

    The new walls aside from protecting the buildings from tsunami waves, I think they will act as an additional barrier in case the reactor building suffer fire or explosions, like the one in unit 3 in Fukushima, that sent debris damaging several buildings around the unit, I don't know if they will provide some radiation protection to workers in case of emergency.

    The amended regulations say: []

    Article 17-2 The organization shall draw up plan for each of the folloeing in
    order to improve system for maintaining reactor facilities under circumstances where tidal waves cause loss of function to all the facilities receiving alternating-currentpower, all the reactor cooling facilities utilizing seawater and all the facilities for spent fuel pool cooling (“Station Blackout”).
    (1) Allocate staff in order to maintain reactor facilities under Station Blackout.
    (2) Train staff who operate to maintain reactor facilities under Station Blackout.
    (3) Install power source cars, fire-fighting vehicles, fire fighting hoses and other equipments necessary for operation to maintain reactor facilities under Station Blackout.
    2. The organization shall conduct activities to maintain reactor facilities under Station Blackout based on the plans mentioned above.
    3. The organization shall conduct periodic evaluation on the matters mentioned in Paragraph 1. and 2. and based on such evaluation, take necessary measures.

    Now, we shall be looking the start of improvement works in a pair of months in NPS around the world; that, if the nuclear industry really wants to survive this disaster.

Order and simplification are the first steps toward mastery of a subject -- the actual enemy is the unknown. -- Thomas Mann