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One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

AmiMoJo writes The operator of the damaged Fukushima Daiichi nuclear plant says more than one trillion becquerels of radioactive substances were released as a result of debris removal work at one of the plant's reactors. Radioactive cesium was detected at levels exceeding the government limit in rice harvested last year in Minami Soma, some 20 kilometers from Fukushima Daiichi. TEPCO presented the Nuclear Regulation Authority with an estimate that the removal work discharged 280 billion becquerels per hour of radioactive substances, or a total of 1.1 trillion becquerels. The plant is believed to be still releasing an average of 10 million becquerels per hour of radioactive material.

22 of 190 comments (clear)

  1. One trillion becquerels by Anonymous Coward · · Score: 4, Insightful

    So....is that bad?

    1. Re:One trillion becquerels by Anonymous Coward · · Score: 2, Funny

      It's terrible. We have, what, seven billion people on earth? Now there's a population explosion and all of a sudden we have a trillion Scott Becquerels. They can't create Quantum Leap reboots fast enough, and everyone is scrambling to keep all Star Trek-related scripts away from them.

    2. Re:One trillion becquerels by Anonymous Coward · · Score: 2, Insightful

      So instead of a pro-nuke justification put in terms of banana equivalent doses we get FUD with undefined threats against our lungs and other vital organs? You thought yourself better than the hypothetical poster you so fear?

  2. I also measure distance by Anonymous Coward · · Score: 5, Informative

    in miles per hour. No but seriously, Bq is disintegrations per second. It's a convenient way to quantify radiation if you have one isotope or it's contained in a small area, but is absolutely ass for a situation like this.

    1. Re:I also measure distance by Artifakt · · Score: 3, Interesting

      Even though they measure the same thing, the Becquerel is a very, very small unit. If somebody was talking about the risk of a dam breaking, and used the cubic centimeter for measuring the volume of water behind that dam, perhaps with a note that a single cc of water can killl a person if they choke on it just right as a justification, wouldn't you still prefer a unit such as gallons, or cubic feet or cubic meters, Wouldn't that be better in helping asses the real consequences of a dam failure even though we are measuring the same thing? Or wouldn't it be better to give information on just how many acres downstream would be flooded and how many people live on that floodplain, even though that's all a very different kind of measurement? There are plenty of cases where either a similar measurement that uses units more in keeping with the situation or a measurement of something different may either or both be better.
                Using SI units is a good thing overall, but what if those units are many orders of magnitude outside of the thing they were designed to measure and there's a non-SI unit that isn't? Or, what's the point in preferring Km./liters over miles/gallon if we are talking about how much fuel it took to send Voyager 1 outside the heliopause? Neither one is very useful when we are not exactly sure just where the edge of the solar system is, or how to measure it, and Voyager will keep on coasting many light years farther in the end, if its trajectory even has an end in the lifetime of the universe.
                  I see using becquerels in this case as similar to someone being opposed to a government project, so they give how much it costs in the currency of some nation currently undergoing hyperinflation, so the project costs a bajillion, bajillion, Saganillion Elbonian Smerdlaps, That's not the same thing as writing about the US economy for a European audience and converting to Euros, or writing about the European economy for Japan and converting to Yen. Even though we know a conversion rate for the uints, and it's fixed as of a given date,,using some units for currency could still be an attempt to make the numbers sound so large they prejudice the average reader more than they inform. You should look at what level of information the average person reading an article from that particular source will have in deciding whether a difference of units is simply a difference or if there's some intent to mislead - and since you asked it as in what way X is :bad?", hopefully we can agree attempts to mislead are bad.

      --
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    2. Re:I also measure distance by Artifakt · · Score: 2

      Oooops! I would drop an 's' from assess and make it asses. Why just mispell something when you can make what someone will probably call a Freudian slip, after all? Please excuse me.

      --
      Who is John Cabal?
    3. Re:I also measure distance by Solandri · · Score: 4, Informative

      Bq seems a fair measure to me. It's a measure of radioactivity. Would you prefer pounds (or kilograms) of X, with no measure of the rate X is releasing radiation?

      It's a bad unit to use in this context because it's a measure of individual atomic decays per second. It's kinda like you asking me how far you have to walk to get to the nearest bus stop and me telling you the distance in angstroms. The scale is just completely devoid of any common reference frame for the number to be intuitively useful (not that most people have a common reference frame for radioactivity). That's why Bq is commonly used by people trying to scare the public about radioactivity - when you're talking about a lot of material like, oh, a field, it results in really, really big numbers.

      Let's put it this way. A block of soil one square mile by 1 foot deep (790,000 m^3) has a natural radioactivity of 653 billion Bq. If they excavated 1.1 trillion Bq of radioactive material from Fukushima, then they removed about as much radioactive substances as is naturally contained in 1.7 square miles of soil one foot deep. Of course the piece of information that we're missing (and no it's not in TFA) is how much volume of material they removed. If we knew that, we could come up with a ratio and say "Ah hah! The stuff they removed is x times more radioactive than the natural radioactivity of dirt!"

    4. Re:I also measure distance by AmiMoJo · · Score: 2

      The units are not that important, what matters is the relative numbers. The point of the story is that TEPCO is failing to prevent the release of radioactive material from the plant in enough measure to contaminate nearby crops and make them worthless. Relatively speaking the amount of released material is lower now, but expected to rise once they start further decommissioning work.

      In this case the unit used by TEPCO and the government is Becquerels, and there has been a great deal of discussion about it in the Japanese media so people are aware of the issues. It serves as a measure of how effective TEPCO's efforts to reduce emissions is.

      --
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    5. Re:I also measure distance by gewalker · · Score: 2

      Conveniently, there is an even better comparison. You have to disperse all of the radioactive soil into the air to make a similar comparison. We don't actually pump soil into the air though. We do however burn coal.

      Webpage According to the National Council on Radiation Protection and Measurements (NCRP), the average radioactivity per short ton of coal is 17,100 millicuries/4,000,000 tons, or 0.00427 millicuries/ton. This figure can be used to calculate the average expected radioactivity release from coal combustion.

      Converting this to metric equates to about 0.174 MBq/ton (metric ton).

      WebpageLargest coal plant in America burns 11 millions tons of coal per year.

      Now 11,000,000 tons * 0.174 MBq / ton is 1.914e6 MBq -- a bit less than the twice the totally scary 1 trillion Bq

      The average coal plant burns coal with around 0.5 trillion Bq / year

      Now, not all of the radiation get released into the atmosphere, a lot of it ends up in the ash. But the ash is stored in ponds and left in piles on the ground, so its not a terrible improvement in terms of safe radioactive containment.

  3. Re:English motherfucker, do you speak it? by Cyberax · · Score: 5, Informative

    One Becquerel means one decay per second. So Fukushima each month emits radioactive material that adds additional 1 million decays per second to the environment.

    This is a very small number, the natural activity of radioactive materials inside a human body is about 10000 Bq. One gram of radium is 37 billions Becquerels. So the whole Fukushima disaster emitted the equivalent of about 30 grams of radium, not a trivial amount anymore, but still very small on the global scale. For comparison, one ton of uranium-bearing minerals contain about 0.1g of radium.

  4. Re:Is that a lot? by calidoscope · · Score: 2, Informative

    Not that much. A typical Tc99m scan involves injection a bit over a billion (10E9) bq per person, albeit half life is only 6 hours. Reminds me of a "warning sticker" for a CB radio - "Danger 5,000 milliwatts".

    --
    A Shadeless room is a brighter room.
  5. Dr. Evil Says... by Irate+Engineer · · Score: 4, Funny

    (holds pinkie to corner of mouth).."one *TRILLION* Becquerel!" (uproarious laughter from nuclear engineers)

    --

    Left MS Windows for Linux Mint and never looked back!

    Vote for Bernie in 2016!

  6. Re:Pick your units of radiation... by Noah+Haders · · Score: 4, Informative

    agreed, the bequerel as a unit is bad enough, but it's even worse when people mis-use it. A bequerel isn't a count of something, like coulomb or joule (or "atoms popping tops off") but rather a rate, like amperes or watts. it's (atoms popping off) per second. so the notion of "bequerels per hour" makes no sense, or "a total of N bequerels".

    the best you can do, if you want to measure the number of atoms blowing their wad over a period of time, you multiply the atoms-blowing-chunks-rate with the number of seconds in the time period. So, if something has a radioactivity of N bequerels, then there are 3600 * N atom pops per hour. Or, as we do with electricity, you could measure atomic pops with the unit bequerel-hours. You could also say "my atomic trash emitted N bequerels (or N/3600 bequerel-hours) over the course of the clean-up period.

    honestly, the bequerel-hour may be the most common-sense method to measure radioactivity. It's grounded in the physical world (atomic pop-offs) unlike things like greys, and it's similar enough to watt-hour that people will use it right.

  7. Re:Pick your units of radiation... by Anonymous Coward · · Score: 2, Informative

    No.

    A dose released in a short amount of time is much more damaging than a dose released over a long period of time.
    If you have a high dose*time over a second, the body won't be able to heal itself.
    If you have the same dose over 10 years, your body can heal the damage.

    Also, the Bq is a worthless unit because it doesn't tell you *what* is released.
    A decay that releases a low energy beta is fairly harmless, but if it releases a 10 MeV gamma, that is very bad.

    But then again, I'm just some "pro nuc AC", so maybe you should rely on people who don't know what they are talking about.

  8. Re:Bq? by WaffleMonster · · Score: 2

    Can you name one person who died at Fukushima due to radiation poisoning or cancer? Just one will do, thanks.

    If you can't name a specific person does this mean something important?

  9. Re:So does this mean I shouldn't visit Japan? by Tablizer · · Score: 3, Funny

    Relax, I see nothing but glowing reviews.

  10. Beware of people - natural radioactivity of 40K by KAdamM · · Score: 2, Interesting

    For your information, an average human body contains natural radioactive isotope of potassium - 40K. Every second there are approx. 3000 decays (Bq) of that isotope in your body. It means that every man is approx. 9 billions Bq "on release" per year. 40K emits 1460 keV gamma-ray (that easily goes out of your body) in about 10% of decays, the rest ends in beta-particle only, that stays inside. That's one of the problems of measuring release in Bq, which is not a good idea. Anyway, your one trillion Bq is equivalent of mere 1000 people, if you measure radiation that goes outside of man body. If Fukushima scares you, stay away from people. Don't hug them, kiss them, or - that's the most dangerous - sleep all night near them. Avoid crowded public places, gatherings, public transportation etc. Build a lead bunker. Wait! Radioactivity is already in your body!

  11. Re:Pick your units of radiation... by nojayuk · · Score: 4, Interesting

    A cubic kilometre of seawater contains about 10 trillion becquerels of the naturally-occurring potassium K-40 isotope. That's ten fucking disasters per cubic kilometre using your scale and there's a lot of seawater on this planet (1.3 billion cubic kilometres according to most sources).

  12. Re:Pick your units of radiation... by DamnOregonian · · Score: 5, Insightful

    I prefer to measure it as .006 USCoalBurningEmissionsYears.

    I don't believe that's an SI unit, though.

  13. Real world consequences by Required+Snark · · Score: 4, Informative
    Now that the Slashdot Pundits have made fun of a number, here's what's happening in the real world.

    According to researchers, monkeys in the vicinity of Fukushima City had detectable levels of radioactive cesium in their muscles, while the northern monkeys did not. Researchers also found that the Fukushima simians had significantly lower white and red blood cell counts compared with macaque troops almost 200 miles away.

    The researchers suggested their findings mirrored studies conducted on human health impacts following the Chernobyl disaster, where researchers found decreased blood cell counts in people living in contaminated areas.

    http://www.latimes.com/science/sciencenow/la-sci-sn-fukushima-monkeys-20140724-story.html

    The Chernobyl site is in the process of having a New Safe Confinement structure built, which will keep radioactive material from the disaster site from entering the environment for 100 years. Once it is in place some of the radioactive material will be broken up and moved to long term buried storage.,

    In contrast, one of the articles states "The plant is believed to be still releasing an average of 10 million becquerels per hour of radioactive material." The quoted 1.1 trillion BQ figure was the result from recent debris removal.

    Up to 1.12 trillion becquerels of cesium was dispersed last summer as debris was removed from the battered building of reactor 3 at the Fukushima No. 1 nuclear plant, with tainted rice later being found in Miniamisoma, Fukushima Prefecture, according to Tokyo Electric.

    The amount of cleanup and debris handling remaining is immense compared to the work done in this last operation. This means that the impact of future work will be proportionally larger.

    Beyond that, the three damaged cores are still not stable or safe. There is no solid information on the state of cores, or even if the core material is in the containment structure. At least one of the cores is believed to have suffered a complete meltdown and become corium.

    The already severely damaged reactors are still at risk for future earthquakes, tsunamis and typhoons. Any one of these events could result in another large scale radiation event. The Fukushima disaster is not necessarily over. It's just less active.

    So go on and giggle over a number. It shows that you have the collective intelligence of a retarded 11 year old.

    --
    Why is Snark Required?
    1. Re:Real world consequences by argStyopa · · Score: 2

      FUD, now in "patronizing" flavor.

      To suggest that critiquing a stupid unit of measure is somehow trivializing the problem is itself a strawman.

      If I said that I'm 1,930,400,000,000 picometers tall, people SHOULD mock me for using a stupid unit of measure. When people are primed to overreact to an event like Fukushima and then confronted by a number in public reporting that uses just such an inappropriate unit of measure, one can either mock the report for being foolish, or condemn it for being deliberately inflammatory. Which would you prefer?

      --
      -Styopa
  14. Re:Pick your units of radiation... by nojayuk · · Score: 2

    Ten trillion nuclear disintegrations of potassium-40 occur in a cubic kilometre of seawater every second. A single nuclear disintegration per second is a becquerel (Bq). Usually Bq are qualified by being associated with a mass or volume, Bq/litre or Bq/kg. Radioactivity in seawater is usually measured in terms of litres but if you make the sample size big enough (cubic kilometres) the numbers can look really scary.