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Japan Earth

Crack In Fukushima Structure May Be Leaking Radiation 280

SillySnake writes with this excerpt from Reuters: "Tokyo Electric Power Co (TEPCO) said it had found a crack in the pit at its No.2 reactor in Fukushima, generating readings 1,000 millisieverts of radiation per hour in the air inside the pit. 'With radiation levels rising in the seawater near the plant, we have been trying to confirm the reason why, and in that context, this could be one source,' said Hidehiko Nishiyama, deputy head of the Nuclear and Industrial Safety Agency (NISA), said on Saturday." Also of interest: Cryptome is featuring high-res photos of the reactor site, taken by UAV.
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Crack In Fukushima Structure May Be Leaking Radiation

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  • "May Be" (Score:2, Insightful)

    by Anonymous Coward

    For Technophiles at /. its always "maybe" when things are already happening? Are you living in the past or something?

    • Re: (Score:2, Funny)

      by Anonymous Coward

      Shut up, luddite! Nuclear energy is safe and clean! Nothing is happening! LALALALALAAAAA!

  • by Kyusaku Natsume ( 1098 ) on Sunday April 03, 2011 @11:04AM (#35699576)

    here: []

    -Today at around 9:30 am, we detected water containing radiation dose overc
      1,000 mSv/h in the pit* where supply cables are stored near the intake
      channel of Unit 2. Furthermore, there was a crack about 20 cm on the
      concrete lateral of the pit, from where the water in the pit was out
      flowing.(We already informed.) During the same day, we injected fresh
      concrete to the pit, but we could not observe a reduction in the amount
      of water spilling from the pit to the sea.
      Therefore, we considered that a new method of stopping the water and
      determined to use the polymer. Necessary equipment and experts of water
      shutoff will be dispatched to the site and after checking the condition,
      we're doing continuous work to stop water by injecting polymer(April 3rd).
    -Monitoring posts of No. 1 ?No.8 set up near the boundary of power station
      area have been restored. We will periodically monitor the data and
      announce the results of monitoring.

    This crack maybe explains why the levels of I-131 had not dropped at the same rate than in the previous days in the readings of I-131 and Cs-137 published by MEXT in their readings of radiation and contamination of water by prefecture page. [] In most prefectures they have dropped to levels that are not detectable but in a few the levels of Cs-137 have increased.

    • WTF?

      "Today at around 9:30 am, we detected water containing radiation dose over 1,000 mSv/h in the pit"

      That doesn't make any sense. Sievert is a measure of absorbed radiation dose. The measure of 'radiactiveness' is Becquerel/Curie (per liter, kilogram, mole).

      • by emarkp ( 67813 )

        Yah, I had the same WTF moment when they started using mSv all the time. Apparently they're also using it to weight different types of radiation (alpha, beta, gamma). First time I've seen it used like that.

        • I guess that they are doing it this way to provide the public with a rough capability to do comparisons between what is reported in local measurements versus what they are reporting at the emergency site. In case of water contamination, they are using an equivalence of 1Bq/litter = 1Bq/kg that for practical matters is good enough.

      • by khallow ( 566160 )
        They probably measured in Becquerels and then weighted the components of the radiation by estimated biological effect.
  • 1,000 millisieverts of radiation per hour

    I don't understand. Can someone translate that into old-fashioned units like luminous watches per hockey game?

    • According to Wikipedia:

      0 – 0.25 Sv (0 – 250 mSv): None
      0.25 – 1 Sv (250 – 1000 mSv): Some people feel nausea and loss of appetite; bone marrow, lymph nodes, spleen damaged.
      1 – 3 Sv (1000 – 3000 mSv): Mild to severe nausea, loss of appetite, infection; more severe bone marrow, lymph node, spleen damage; recovery probable, not assured.
      3 – 6 Sv (3000 – 6000 mSv): Severe nausea, loss of appetite; hemorrhaging, infection, diarrhea, peeling of skin, sterility; de
    • by BobGregg ( 89162 )

      >> 1,000 millisieverts of radiation per hour

      If it helps, this is equivalent to 1 Sievert/hour.

      You're welcome.

      • If it helps, this is equivalent to 1 Sievert/hour.

        Thank you! milli = 1 / 1,000
        I only first heard of millisieverts last month,
        but the men reporting all throughout that month have NEVER heard of fractions and unneeded redundancy. More likely, the thousand must be there for shock value.

        In real life, nobody ever says "1,000 millimeters" or "1,000 milliliters."

    • by Arker ( 91948 )
      Best I can tell it means that standing by that crack for an hour would be sufficient to make you very sick, and possibly fatal.
    • Re: (Score:3, Informative)

      by jheiss ( 10829 )

      1,000 millisieverts of radiation per hour

      I don't understand. Can someone translate that into old-fashioned units like luminous watches per hockey game?

      Various sources[1,2] indicate a range of 1-100 mrem/hr for a radium watch face, with about 20 mrem/hr looking like a plausible average. 1 mrem == .01 mSv[3], so 1000 mSv is about 5000 watch faces/hr. Apparently a standard ice hockey game is 60 minutes[4], so:

      1000 mSv/hr == 5000 radium watch faces/hockey game


      [1] []
      [2] []
      [3] []
      [4] []

  • Do you think those high-res photos of the reactor site will give inspiration for some bad-ass fps even more realistic than S.T.A.L.K.E.R.?

    I don't, but they could.

  • The title should be "Crack In Fukushima Structure May Be Leaking Radioactive Materials". When I hear "leaking radiation" I think of a neutron beam shooting out the crack. :-P

  • 1,000 millisieverts implies four significant digits of precision... I wish they wouldn't do that... just say "1 Seivert" and be done with it.

    • Because 1000 sounds so much 'better' (in the media sense of the term) than '1'.
    • Why wouldn't they have four significant digits of precision? I believe it possible to measure even microsieverts per hour.

      • because I keep hearing exactly 1,000 ... I never hear 1,005 or 1,002 .... I somehow doubt that the measurements are always exactly 1,000 millisieverts
        false precision

    • When was the last time you told someone you drove 1 Mm, instead of 1000 km? Or if you are being pedantic about 4 sig digs - Is the Moon 360,000 km or 360 Mm far away? I bet you say 360,000 km or rather 360 thousand km and don't mean 5 sig digs. There are standard units and typical domains - and we used mS for these domains. In computing we have all gotten used to byte, kb, Mb, Gb, Tb and Pb, and translate between them. But we don't often mix up km, m, cm, mm, um, nm, pm because they are different domains
  • They have tried twice now to plug the crack - first with a load of concrete, and then with an expanding polymer. Both failed, which makes me suspect the crack is a lot deeper than they think it is. Deep cracks in the ground are not terribly surprising after a magnitude 9.0 earthquake. They may have to cofferdam the water upstream of the crack, and then dig it out the surface concrete, and fill it before patching it again. A cofferdam is a temporary barrier to keep water out of a construction site.

  • It appears to me the rating system is broken.

    Why should a perfectly sincere and polite post end up with -1, just because it is against the opinion of the moderator?

    If that is what moderating is for, then maybe there should be a -1 "disagree" option, and the easy to abuse "Underrated"/"Overrated" should be gone. I say easy to abuse because there is a small risk for negative metamoderation for these.

    Why not have a multidimensional rating system, maybe using left wing and right wing or INTP as in the psycholog

  • by DrJimbo ( 594231 ) on Sunday April 03, 2011 @02:16PM (#35700976)

    NOTE: This post is mostly recycled from a previous post at the bottom of a thread under the previous Fukushima story. The thread started with a post I made warning that most of the radioactivity leaking from Fukushima was moving downward into the ground and ocean, not upward into the air.

    Filling the crack and fixing this leak won't reduce the amount of radioactive material spewing from reactor #2 into the environment. This pit and the concrete with the crack in it were never intended to be part of the containment system. If they succeed, then the HRW (highly radioactive water) will either (a) find another way into the sea, or (b) further contaminant the groundwater, or (c) flood the ground and then do (a) or (b). Depending on the total amount of radioactivity released, it *might* actually be better to pour this HRW into the ocean where it will be diluted down to safe levels.

    The term "containment" has a fairly precise technical meaning (BTW: I've got a Ph.D. in nuclear physics but not nuclear engineering). These reactors are basically a bottle in a bottle. The inner bottle is the pressure vessel and it is used to maintain pressure for the creation of steam and electricity. The outer bottle is 10cm or 20cm thick stainless steel. It is called the containment vessel. Its sole purpose in life is to contain all the radioactivity in the event the fuel rods melt down. Normally almost all the radioactivity is contained in the zirconium clad fuel rods. That is why there can be HRW 100,000x higher than the water found in a functioning reactor. Almost all of the radioactivity in a functioning reactor of this type is contained in the fuel rods. When the fuel rods melt down, high levels of radioactive materials contaminate the water making it highly radioactive.

    Up until last week, the word "containment" had the simple and obvious meaning of radioactive materials staying inside the massive stainless steel containment vessel. I believe TEPCO forged a new meaning in order to downplay the significance of the HRW that was found in the turbine buildings. I will use the traditional technical definition, not the new one invented by TEPCO.

    You see, the idea was that as long as the radioactivity was kept inside the containment vessel then you could safely operate the plant and move around in it. The environment was safe. The control room was safe. The turbine building was safe. Even the reactor building was safe (as long as you stayed out of the containment vessel and storage pool). Everything was safe. One of the difficulties caused by a loss of containment accident is that it becomes difficult and dangerous to work on the plant. That is why they need to pump out the turbine buildings before they work on restoring the cooling. If they hadn't lost containment (in the traditional sense) this would not have been a problem.

    The pit, the tunnels, and even the turbine buildings were not designed to contain radioactivity. The buildings were designed, like most buildings, to keep the rain out, etc. For example, right after they had those scary hydrogen explosions that blew apart the reactor buildings, I was assuring people it was not a big deal because those buildings were never designed to contain radioactivity. TEPCO and the government were offering the same assurances.

    When I heard about the HRW in the turbine buildings I stopped issuing reassurances and I started to be greatly concerned because it meant they had lost containment. I was hoping against hope that the HRW in the turbine buildings was a fluke and that it hadn't spread elsewhere. When I then then heard the tunnels outside the turbine buildings were flooded with HRW I knew this was a serious accident, much worse than Three-Mile Island. When I heard there were 18,000 tons of HRW outside of containment (that number has now been reduced to 13,000 tons) I knew this was a big fucking deal and I was surprised that the Western press were ignoring these developments even though they had been h

    • by Xylantiel ( 177496 ) on Sunday April 03, 2011 @05:17PM (#35702344)

      Just to say up front, I think this is the most significant nuclear incident ever, and I expect it to have a huge effect on nuclear safety design and regulation. Chernobyl was being intentionally operated outside of spec and was a stupid design to begin with and TMI didn't actually release any harmful materials.

      But to put it simply... you do not know very well what you are talking about.

      Up until last week, the word "containment" had the simple and obvious meaning of radioactive materials staying inside the massive stainless steel containment vessel.

      No, in reality, there are many layers to the containment, each of which contains different things to varying degrees. The outermost containment is the building itself, and in the case of a boiling water reactor this includes the turbine building because H20 that comes in contact with the core is circulated through the turbines. For example, steam containing radioactive contaminants can be vented into the building (outside the steel vessel) and still maintain zero external contamination. The big problem at Fukushima is that the top half of the reactor buildings are GONE. "containment" by your definition was lost with the first hydrogen explosion because the vented gas could then escape into the environment.

      This is so far beyond a simple loss of containment accident that it is not funny. But the containment of raw core material itself is not really in terrible shape. The big problem is that the buildings are half-demolished from the hydrogen explosions. So all the plumbing and wiring and such are completely trashed. Things don't just need to be "fixed" they have to be rebuilt almost completely. Working on site is difficult, but not impossible. Every time they localize some contamination is a huge step forward because it means they know what they are dealing with and can make progress.

      But back to the core breach, or to be more precise the core coolant leak. They have been saying all along that there were good chances of a leak from the reactor core, and what is happening seems like one of the less bad types of that. The cores have partially melted, so that radiative materials can mix into the water. That water has been able to leak. So far there is evidence of mostly "volatiles", mostly iodine and cesium, not much heavier stuff. But they seem to have isolated it to reactor 2. This breach was caused by, wait for it... a hydrogen explosion (you seeing a theme here?).

      If they can get the contaminated water under control then a big piece of the wider impact will be more or less under control. This is why they are trying to pump this stuff out of the basements, because nobody thinks they will be strictly water tight. But that has proven challenging (where do they put it?). In the mean time if they can plug a few leaks they can reduce (not yet stop) the external impact, so that's what they are trying to do.

      • by DrJimbo ( 594231 )

        But to put it simply... you do not know very well what you are talking about.

        You know, it's a funny thing, people were saying that and worse when I warned that most of the radioactivity was leaving the plant downward in the water, not upward in the air. What was a crackpot idea a few days ago is now obvious today:

        If they can get the contaminated water under control then a big piece of the wider impact will be more or less under control.

        Exactly my point. But that's a very big "if".

        This is why they are trying to pump this stuff out of the basements, because nobody thinks they will be strictly water tight.

        This is not what TEPCO and the Japan government have been saying. They have consistently said that they are pumping out the turbine buildings to make them safe enough so they can go back to work restoring the primary cooling sy

  • All we hear is more of the same day in and day out. They're doing this, oh and we discovered that. They're now leaking cesium 141 into the ocean which has a half life of 30 years vs 8 days with the iodine. And ocean water flows clockwise towards the US and our fishing waters. After transocean were going to find we have very little seafood that's not contaminated because of human activity.

    The government needs to get their power company out of the picture and work on real solutions, that power company is

    • by lennier ( 44736 )

      The government needs to get their power company out of the picture and work on real solutions

      They would, but magic wands capable of dispelling multi-Sievert-level ionising radiation are highly restricted after the unfortunate international incidents which led to the 1948 Treaty of Avalon and the 1949 Geneva Conventions on Thaumaturgical and Faerie Invocations.

      I'm sure no head of state wants to see a repeat of those dark post-war years when entire European cities were instantaneously converted to chocolate pie, rose petals, or in one particularly gruesome case, a gigantic olive martini.

      A few thousan

  • by rickzor ( 1838596 ) on Sunday April 03, 2011 @03:15PM (#35701444) []
    includes lots of ground and non-aerial photos.

"Call immediately. Time is running out. We both need to do something monstrous before we die." -- Message from Ralph Steadman to Hunter Thompson