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Japan Raises Nuclear Plant Crisis Severity To 7 673

darkonc writes "Early Tuesday in Japan, the government decided to raise the severity level of the accident to the maximum 7 on an international scale, up from the current 5 and matching that of the 1986 Chernobyl catastrophe. The government declared the level 7 emergency because it is now estimated that the crippled plant was emitting over 10,000 terabecquerels of radioactivity for a number of hours at the height of the nuclear incident. Previously, on Monday, the government had expanded the evacuation zone around the plant to include at least 6 cities up to 60 km away from the plant. These cities, outside of the current 20-30 km evacuation area, are now expected to exceed the 20 millisieverts/year limit on residual radiation established by International Commission on Radiological Protection and the International Atomic Energy Agency in the case of an emergency."
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Japan Raises Nuclear Plant Crisis Severity To 7

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  • by sincewhen ( 640526 ) on Tuesday April 12, 2011 @08:20AM (#35791656)

    And some people still wonder why the public are opposed to nuclear power.

    • by DamienRBlack ( 1165691 ) on Tuesday April 12, 2011 @08:24AM (#35791684)
      This crisis, bad as it is, is still just a drop in the bucket compared to what we may be doing to our atmosphere with coal. I'd take a world powered by nuclear any day. At least the problems with nuclear are local-ish.
      • by Mindcontrolled ( 1388007 ) on Tuesday April 12, 2011 @08:33AM (#35791750)
        Local-ish, like me, in my hometown 1000 miles from Chernobyl, not being able to collect mushrooms due to Strontium contamination, today? I completely agree that coal has to go, but hopefully, nuclear will be only a temporary solution, to be phased out for renewables in the next decades.
        • by Kokuyo ( 549451 ) on Tuesday April 12, 2011 @08:52AM (#35791922) Journal

          Talking about 'nuclear' as if there was exactly one fuel and one reactor design involved is like thinking a Prius, a Tesla and a '69 Corvette all work the same way.

          Maybe, just maybe, the answer doesn't lie behind the question of whether we want nuclear power or not. Perhaps we should think about nuclear alternatives. I still say "Yay for LFTR!"

          • by shilly ( 142940 )

            Nope, it's like saying "there may be designs out there that are safe, but there's plenty of 1970s plants with these vulnerabilities designed into them, and each one of them is a potential massive cluster-fuck. So let's focus on those, shall we?"

            • by squizzar ( 1031726 ) on Tuesday April 12, 2011 @09:00AM (#35792044)

              You mean the politicking stops and someone either shuts them down or replaces them? At the moment no-one wants to deal with losing the fairly significant contribution that nukes make to our energy supplies, presumably the lights going out is a vote-loser, but no-one wants to build newer safer ones, presumably because it's a vote loser. The most stupid thing about the situation is that the middle ground is the most dangerous - blocking progress and the development and construction of better safer plants and meaning the older plants get lifetime extensions.

              • by shilly ( 142940 ) on Tuesday April 12, 2011 @09:09AM (#35792152)

                No, I don't think shutting them down or replacing them makes sense.

                Industrial gear is regularly in operation for many decades, especially when it's expensive. Trains and planes are often kept going for 30+ years, for example. Buildings often have lifespans in the centuries. No-one is going to invest in a nuclear powerplant that has to be ripped down after 20 years because it's outdated, not least because decommissioning costs a bloody fortune due to the large amounts of waste that have to be dealt with. Nuclear plants are routinely expected to operate for 30+ years. It's just unrealistic to expect that we're going to see widescale decommissioning of large numbers of 1970s and 1980s reactors, due to the economics alone.

        • Re: (Score:3, Insightful)

          Renewables will never have the energy density required to completely power our world, and will always depend on fickle things like the wind and the clouds. Either we carpet every available inch with solar panels, and plant every plain full of wind farms, or we move to more exotic power sources, like piezo sidewalks and nano-generator clothing (both of which I consider sci-fi despite working in labs, and piezo flooring has even been deployed in Japan (I guess the earthquake generated at least some power, eve

          • Stochastic does not mean unpredictable. And the "carpet every inch with solar panels"-thing conveniently leaves out solar thermal, which has an intrinsic storage capacity.
          • by Weezul ( 52464 ) on Tuesday April 12, 2011 @09:37AM (#35792530)

            We expect the world population will be in decline by mid century, due to the liberation of women, access to birth control, etc. If given the option, women prefer having fewer children and investing more effort in each child. It follows that our overall world consumption could eventually be covered by reasonable usage of wind, wave, solar, and geothermal.

            There are large wind turbines that power 500 homes already, for example. Yes, it'll require several ass wind turbines standing above every suburb to power both that suburb and the city, but hey the burb's always did suck anyways. Also, there is much faster technological progress on wind, wave, and solar than civilian nuclear because they exist at scales that human handle better.

            Btw, aircraft, spacecraft, and ships are our only vehicles that fundamentally require high energy density. All our current car designs require high energy density too, but a ground level power [] standard for highways could solve that problem for electric cars.

            Are you familiar with what most infrastructure projects look like after a couple decades in operation? Nuclear power simply doesn't give enough room for the inevitable screw ups. You simply cannot trust either governments or private enterprise to handle the task long term. You could mandate that the family of every power plant owner and worker lived inside the plant, but you'd still find people dangerously cutting corners.

            There will for example be another Chernobyl coming down the line in Bulgaria's nuclear industry now that they're completely run by organized crime. ( see ) Italy's mafiaa has also decided it wants some part of the nuclear power pie. Do you remember when the garbage was piling up in Naples?

            • by Luckyo ( 1726890 )

              We expect the world population will be in decline by mid century, due to the liberation of women, access to birth control, etc.

              If you're even marginally believing in this, you're beyond naive. Poor people will continue to breed as much as they can. Religious people will do so as well. With power distribution in democratic countries being based on pure numbers, these will continue keeping most of Africa and central Asia exploding with people.

              And of course, there's a significant threat of all Western democracies going the way of Israel. At the start, a small religious minority that breeds fast (10 children per woman) vs ~2 children f

            • by cjb658 ( 1235986 )

              We expect the world population will be in decline by mid century, due to the liberation of women, access to birth control, etc. If given the option, women prefer having fewer children and investing more effort in each child.

              Have you been outside the US and Europe? Most of the undeveloped world does not share this philosophy.

      • At least the problems with nuclear are local-ish.

        Localish ? 2000 km away, we could not anymore eat fish from the lake during a while.

        • And yet everywhere pregnant women are told to not eat too many fish due to mercury?

      • Re: (Score:3, Insightful)

        by cronius ( 813431 )

        In Norway nearly 100% of the electrical power used and produced is from renewable energy. The government of Sweden has started working on getting the country completely independent of oil (without building more nuclear power plants). Norway, England, Italy, the US and others have started to look into floating (deep water) offshore wind power as a future energy source.

        Wake up and smell the coffee. Comparing nuclear to coal is fucking bullshit.

        • by fridaynightsmoke ( 1589903 ) on Tuesday April 12, 2011 @09:21AM (#35792304) Homepage

          In Norway nearly 100% of the electrical power used and produced is from renewable energy. The government of Sweden has started working on getting the country completely independent of oil (without building more nuclear power plants). Norway, England, Italy, the US and others have started to look into floating (deep water) offshore wind power as a future energy source.

          Wake up and smell the coffee. Comparing nuclear to coal is fucking bullshit.

          Perhaps after a few billion years the whole world might have plentiful fijords and geography suitable for large scale hydro, then we might all benefit from it in the same way that Norway and Sweden do. Until then they're a complete red herring.

          As for offshire wind, great; we just need to crack the whole energy demand - windy period mismatch, or the epic civil engineering challenge and power losses from having an intercontinental supergrid to even things out, then we're all set.

        • Comparing nuclear to coal is fucking bullshit.

          Not in most of the world, it isn't.

          Most of the world does not consist of large cities surrounded by hydro sources, good winds, bright sunshine, and wide open spaces. Norway can build dams - good for them. That's not going to help places like the US that are all dammed up already. Offshore wind power is great, as is solar and geothermal. As these ramp up, though, I'd much rather have some modern nukes operating than to continue to run these 30-40 year old dinosaurs.

      • by hey! ( 33014 ) on Tuesday April 12, 2011 @10:06AM (#35792918) Homepage Journal

        You think we've reached the height of human folly with coal? Well, just wait and see what a crash effort to build our way out of our entirely foreseeable future energy problems can do with nuclear power. And that crash course is coming, because if there's one thing you can count on people faced with a difficult and intractable problem to do, it is absent-mindedly kicking the can down the road until they have to desperately grasp for a quick fix.

        That's why I'm *for* building a modest number of nuclear power plants based on new designs *now*. What goes down, comes up. Today the public is down on nuclear power. When oil hits $200/bbl or more with no return in sight, then all will be forgiven and forgotten. Better to continue to gain knowledge in the technology *before* it's needed. Better to spend a few decades of bickering over the problems of nuclear power than to wait until we're in such desperate straits that even bringing those problems up makes you an enemy of the people.

        I have watched every single president since Richard Nixon declare that dependency of foreign oil is a serious threat to the United States, and I've watched every president since Richard Nixon fail to do anything about that threat, because it's easier to hand that hot potato to the next President. Nuclear is coming, one way or the other, because as a species we don't have the discipline to tackle problems we can avoid.

    • by magsol ( 1406749 )
      It's not hard to see why the public at large is opposed to nuclear power: see the above headline. What is evidently much harder to see is why that opposition is extremely unreasonable, particularly in relation to power by fossil fuels.
      • It's not hard to see why the public at large is opposed to nuclear power: see the above headline. What is evidently much harder to see is why that opposition is extremely unreasonable, particularly in relation to power by fossil fuels.

        It's unreasonable because it's emotional and based on the fear of something that most people don't really understand. Whenever "nuclear" comes up it's hard for many people to imagine anything other than mushroom clouds and Chernobyl.

        I'd be curious about whether a pebble bed reactor would have fared better. If so then this is like so many other things in that it's not about what we do but how we go about doing it.

        • by vlm ( 69642 ) on Tuesday April 12, 2011 @09:19AM (#35792264)

          I'd be curious about whether a pebble bed reactor would have fared better.

          Probably "about" as risky but completely different failure modes. The pebbles are brittle and are going to have issues with a severe earthquake, unlike literally "depth charge proof" light water reactors. If the pebbles don't crack and no coolant leaks, they are harmless. One or the other fails, still harmless. Both simultaneously fail, instant Chernobyl because its yet another graphite moderated design. Once you set one (or a couple) pebbles on fire, it gets hot enough to catch all the pebbles despite the coating, so you gotta spray it down, which means thermal stress will crack em all, making a bigger fire or at least a heck of a mess.

          Most exciting failure mode for a pebble bed would probably be chilling the graphite moderator (tsunami? Pump in sea water?), which eliminates doppler broadening, which turns the power WAY up, at least momentarily. Pop those little tennis balls like popcorn. Then all that red hot graphite can boil off the water and/or make old fashioned town-gas (mostly carbon monoxide gas) which explodes the containment, then the burning graphite roasts all the fission products into the air. Yeah it would be pretty bad.

          So the lesson learned from Chernobyl is don't use a flammable moderator. (except, apparently, for the pebble bed fans)

          The lesson from Japan is going to be don't use flammable cladding, and who cares what the alternatives do to the neutron balance.

          The good news, is once we utterly ban flammable cladding, there's not much in a core that's still flammable, so our problems are pretty much over.

          I suppose we need one more good fire / meltdown of a uranium carbide fueled reactor so we can ban carbide fuel. Then we're all good...

          Without the fire / explosion, the Japan thing would still be a complete economic loss, but there would be no contamination outside the containment structure.

        • It's worth noting that there are 6 reactors at Fukushima, and it's only the oldest 3 that had notable problems. The lesson here is not that nuclear is unsafe, it's that reactors built after 1974 can withstand a 9.0 earthquake and a 15m tsunami. And that we should be retiring older designs at the end of their design lifespan, instead of keeping them limping along because we can't get support to build new ones.

    • by Mortiss ( 812218 )

      And some people still wonder why the public are opposed to nuclear power.

      People oppose the nuclear power because they are fed over-exaggerated headlines by sensation seeking media. "We are facing the next Chernobyl! BOOM!!!" is going to generate many more views than "Humanitarian crisis in Japan caused by widespread flooding."

      • No. People oppose power plants that can poison the planet with radiation and greenhouse gases because they have common sense.
        • Are you saying nuclear power produces greenhouse gases?

          Or are you saying people are against coal?

          Neither makes any sense.

          The real question is how much are these people doing to reduce their energy footprint given that pretty much all of today's power generation methods release radiation and/or stuff like mercury into the atmosphere....

          [sound of crickets chirping]

    • by Nidi62 ( 1525137 ) on Tuesday April 12, 2011 @08:29AM (#35791714)

      And some people still wonder why the public are opposed to nuclear power.

      Because it took a large earthquake, a very large tsunami, and corporate neglect to cause something that, while expensive, has resulted a casualty figure that is lower than what is seen in a day in Libya. On the other hand, it also shows that nuclear technology that is decades old can withstand all but the strongest of natural disasters. If anything, the public should be realizing that modern nuclear technology coupled with real, effective corporate compliance and government monitoring would make nuclear energy extremely safe and productive. This is what the media should be talking about, instead they are fear mongering and spreading any rumor they can find that bumps up ratings, regardless of the veracity of those rumors. A wonder indeed.

      • by shic ( 309152 ) on Tuesday April 12, 2011 @08:45AM (#35791862)

        I am broadly in favour of nuclear energy - in principle. In practice, I have faith in neither corporate compliance nor government monitoring. Neither entity is equipped, or motivated, to appropriately manage long term risk... and that means you can good as guarantee failures. Hysteria about nuclear contamination, IMHO, has made matters worse - encouraging officials to focus exclusively upon reassuring the public that there is "no risk" at the expense of a focus on restricting and mitigating the consequences of the (ultimately inevitable) eventual accident.

      • With adequate safety design, effective corporate compliance, and government monitoring, nuclear energy could be safe.

        The problem is that it would then be economically unfeasible.

    • by Anrego ( 830717 ) * on Tuesday April 12, 2011 @08:39AM (#35791802)

      Nuclear accidents are a lot like train derailments and airplane crashes.

      Statistically, air and train (and nuclear) are very safe but when something goes wrong, it’s very dramatic. Even looking at very conservative statistics for death vs power generated, coal is much, much worse it just kills people at a slow, steady rate such that it seems normal and doesn't get headlines.

    • I don't think we wonder, we know why you appose it. You don't understand it and you fear what you don't understand. You're assuming this accident is far worse than it really is. More people die mining coal on a yearly basis than are killed in all the nuclear accidents (not including bombs of course) throughout the history of nuclear power. This accident in Japan hasn't even killed a single person yet, if you don't include the people killed by the actual earthquake/tsunami.

      It's much like the Air travel is sa
    • by MightyYar ( 622222 ) on Tuesday April 12, 2011 @09:20AM (#35792300)

      And some people still wonder why the public are opposed to nuclear power.

      I don't wonder why. I see a media that gets readership/viewership with sensationalist headlines. I see a nuclear industry that feels backed into a corner and so releases pro-nuclear statements that are laughable in any context, let alone in the midst of one of the worst nuclear accidents of all time.

      But at the end of the day, the facts are these:
      1. The direct cause of this nuclear accident was a catastrophic earthquake and tsunami.
      2. The earthquake/tsunami has killed thousands - maybe 20,000 when all is said and done. The nuclear accident has killed 0. In the long term, it probably has shortened the lives of some plant workers. I'm sure it will get blamed for a couple of hundred cancers.
      4. The earthquake/tsunami has caused hundreds of BILLIONS of dollars in damage. It will take decades to rebuild. The nuclear accident will probably take 10 years or so and hundreds of MILLIONS of dollars to clean up.

      In other words, in the context of the greater disaster, Fukushima is a mess and complicates reconstruction and rescue - but it is not really comparable in numeric terms. We should certainly learn lessons from it and retrofit plants using these lessons - and close those that can't be fixed. But abandon nuclear power? In favor of what? Coal?

  • by Anonymous Coward

    typical /. pro-nuclear apologetic comments arriving in 3..2..1..meltdown!

  • Right Now It's a 7 (Score:5, Insightful)

    by WrongSizeGlass ( 838941 ) on Tuesday April 12, 2011 @08:20AM (#35791664)
    I think using a scale based on 'the worst nuclear disaster so far' isn't a great idea. Do we add #8 'Fukushima' to the scale if it gets any worse?
    • by ratnerstar ( 609443 ) on Tuesday April 12, 2011 @08:33AM (#35791746) Homepage

      My nuclear meltdown scale goes to 11.

      It's one worse.

    • by Talderas ( 1212466 ) on Tuesday April 12, 2011 @08:58AM (#35792014)

      Congratulations. You hit on why the INES scale is deeply flawed.

      I'm going to point to this [] news article which explains far more in depth as to why the Level 7 was chosen. After reading it, you should realize that Fukushima is not as bad as Chernobyl. Here's some summary facts.

      The Level 7 was chosen solely based on the total cumulative release of radioactive isotopes over the course of a month. Chernobyl's release was mostly due to the radioactive plume that was ejected during a one time event.

      The Level 7 covers seven locations. Units 1-4 at Daiichi and three Units at Daiini. Each of these doesn't class over a Level 5 on the INES scale.

      • by rmstar ( 114746 )

        I'm going to point to this news article which explains far more in depth as to why the Level 7 was chosen. After reading it, you should realize that Fukushima is not as bad as Chernobyl. Here's some summary facts.

        Your first fact goes nowhere. If in Fukushima, a few weeks into this, release is still happening, then this looks as it is going to be worse than Chernobyl. Your second fact looks like an odd technicality, but hey.

        I propose the following scale, I am sure you and people like you are going to like it

  • 22,000 people died in the tsunami. TWENTY-TWO THOUSAND. So why isn't the tsunami getting more press? Answer: your elites can't score political points from a tsunami.
    • by Synn ( 6288 ) on Tuesday April 12, 2011 @08:44AM (#35791844)

      Actually it's because we can't do all that much against natural disasters. I live in Florida and "Death by Hurricane" is sort of the deal you make to live here.

      But we don't have to mismanage nuclear power, or focus our (distant) future on it.

      • False equivalency. Much can be done against natural disasters, but none of it serves an agenda. Always ask yourself: who benefits from this?
    • When did 'elite' become a pejorative?
    • by isorox ( 205688 )

      22,000 people died in the tsunami. TWENTY-TWO THOUSAND. So why isn't the tsunami getting more press? Answer: your elites can't score political points from a tsunami.

      People understand tsunamis. They can see it, it's terrible, but then it's over, and has been for a month. They weren't killed. Nuclear is invisible and poorly understood, and that leads to fear. Fear of the effects, but fear of the unknown.

      The bigger story, which is under-reported, is the displaced people, and the shattered lives. Also, the hope and relief we should have as there haven't 220,000 deaths from disease and starvation after the tsunami.

      But people aren't dying, and are unlikely to die

    • by v1 ( 525388 )

      So why isn't the tsunami getting more press?

      Because the tsunami happened and then was over with. The reactor situation is ongoing, and isn't getting better very quickly. There's little point on dwelling on the past, there's nothing anyone can do about the tsunami now, the damage is completely done and over with. There are no new developments. Obviously this translates to "no news".

      Fighting to keep the reactors from melting down and further major radiation releases is a current and ongoing battle. Every

  • about fukushima always minimizing, belittling, or otherwise dismissing what is happening here as hysteria or science illiteracy?

    it seems like a form of denial to me

    we're talking about the end of nuclear power in japan, and perhaps elsewhere

    if you don't understand why, you really are in denial, and you don't understand risk analysis

    it's not hysteria going on here. really

    • by Joce640k ( 829181 ) on Tuesday April 12, 2011 @09:00AM (#35792040) Homepage

      ... you don't understand risk analysis

      Are the anti-nuclear crowd going to drive their cars to the protest? After letting the TSA spend billions of dollars to trample their rights on the flight over there? And receiving a decent dose of radiation on that flight.

      Tell me again about "risk analysis" and how good the average person is at it...

      it's not hysteria going on here. really


      • with false complacency

        you walk the fine line between false complacency and false alarmism with a prudent understanding of what is going on, intelligence. sometimes, you are complacent. sometimes, you alarmed

        and if you are intelligent, you are alarmed about what is going on in fukushima right now. that some people are also alarmed for stupid reasons does not change the fact that alarm is the proper reaction to fukushima right now

        now go ahead, dismiss me as a hysteric or illiterate. denial, denial, denial

  • watch this video (Score:3, Informative)

    by Anonymous Coward on Tuesday April 12, 2011 @08:40AM (#35791814)

    You can't really put things into perspective until you look at this video:

    A few filmmakers went into the evacuation zone. Watch how those geiger counters are going ballistic miles from the plant. Whole cities are going to be ghost towns for our lifetime for sure.

    • by shilly ( 142940 )

      Thank you for posting this. It truly spells out the reality of what has happened. No-one's going to be going back there in a hurry. Very, very sad.

    • Re:watch this video (Score:5, Informative)

      by Ptur ( 866963 ) on Tuesday April 12, 2011 @09:28AM (#35792406)
      This is a prime example of journalists creating hysteria based on their ignorance. The scale on their device never went over 100uS/hr - that's MICRO-Sieverts.... To put this in perspective, read []

      They never risked their lives at all
      • Re:watch this video (Score:5, Informative)

        by ZZane ( 144066 ) on Tuesday April 12, 2011 @10:29AM (#35793252)

        100uS/hr = 2.4mSv per day = 876mSv/year

        So while the journalists didn't risk their lives with that dose, it's definitely not a livable area at those radiation levels. However, depending on the source of the radiation those levels could go down fairly quickly or it could remain at those levels for quite a long time. Of course that assumes no further contamination from the plant.

    • by GreatBunzinni ( 642500 ) on Tuesday April 12, 2011 @09:48AM (#35792684)

      If you pay attention to the scale in those geiger counters you will notice that although it makes a lot of noise it measures radiation in micro sieverts. The geiger counter made the most noise at 15 micro Sieverts. In comparison, an airplane flight from LA to NY earns you 40 micro Sieverts.

      If we rig a thermometer with a siren when temperature hits 30C then it will also sound dangerous. That doesn't make it a danger to your health.

  • by Pascal Sartoretti ( 454385 ) on Tuesday April 12, 2011 @08:45AM (#35791856)
    Just imagine one second this type of accident in China...
  • and washes all that radioactive material inland and then back out to sea we will have to increment the Crisis Severity again... and again... ...several thousand times.

  • by AndyMcL ( 65518 ) on Tuesday April 12, 2011 @08:53AM (#35791940)

    Japan is a great country and the Japanese wonderful people. I lived there in the 90's and loved it. They are showing tremendous resolve and strength during a natural disaster that just keeps on going. It seems like almost everyday I see a headline of yet another 7.x aftershock. Yet they are repairing their infrastructure at an incredible rate and keeping as much control over what they can better than anyone.

    If and when the US has another natural disaster, I hope we can come somewhere close to what they are doing. The Japanese people's efforts are not only helping Japan, but much of the world. Many critical components and products for many industries are made or flow through Japan. If Japan were to stop or slow down noticeably, it would seriously affect economies all over the world including the US.


    • I agree. It's too bad that so many Americans (yes, I'm an American) have the entitlement attitude, and just want "someone else" (usually the government) to take care of things. As if it happens by magic.

  • by PPH ( 736903 ) on Tuesday April 12, 2011 @10:03AM (#35792876)

    Our threat levels are designated by colors! What color is seven?

  • by ledow ( 319597 ) on Tuesday April 12, 2011 @10:11AM (#35792996) Homepage

    Read this, then you may continue whining on regardless about how it's the end of the world: []

    Because if you haven't read this already, or understood what it's telling you, chances are you just like scaremongering anyway.

    • by DrJimbo ( 594231 ) on Tuesday April 12, 2011 @12:18PM (#35795012)

      The Guardian posted an excellent rebutal to this point of view by Helen Caldicott: How Nuclear Apologists Mislead the World Over Radiation []. The article you linked dismissed this article disparagingly with a three word ad hominem attack: "mad Auntie Fear" without addressing, let alone countering, any of her arguments. Instead, the Register article repeats the very mistakes Caldicott had identified.

      Helen Caldicott is a medical doctor. She taught pediatrics at the Harvard Medical School for two years before turning her focus to researching and reporting the health hazards of nuclear power.

      OTOH, Lewis Page [] (assuming it is the same Lewis Page):

      ... served as an officer in the Royal Navy from 1993 to 2004, and is now an author and authority on military matters.

      You can also get an idea of his expertise by looking at his other articles at the Register [].

      It is amazing that you think the article by Lewis Page is authoritative since he has absolutely no expertise on the subject; he totally ignores criticism from a person who is an authority; and he dismisses the authority with a rude ad hominem attack. OTOH, his level of discourse would fit right in with the irrational, faith-based pro-nuclear advocacy here on Slashdot.

  • by Tweenk ( 1274968 ) on Tuesday April 12, 2011 @10:53AM (#35793668)

    I am very annoyed by a critical bit of misinformation being spread about this. Most reports imply that there was some kind of undisclosed escalation at Fukushima, and that the "threat level" was increased.

    This is seriously wrong. INES is not a "threat level" like a hurricane warning. It is a post-mortem estimate of seriousness. This is a reassessment of events which happened weeks ago on the basis of more detailed information being available, not some new unfolding problem.

  • by MrKaos ( 858439 ) on Tuesday April 12, 2011 @11:00AM (#35793768) Journal
    The shame about this disaster is that it was avoidable. The World Nuclear Association [], an organisation that represent reactor manufacturers and TEPCO, states that;

    In March 2008 Tepco upgraded its estimates of likely Design Basis Earthquake Ground Motion Ss for Fukushima to 600 Gal, and other operators have adopted the same figure. (The magnitude 9.0 Tohoku-Taiheiyou-Oki earthquake in March 2011 did not exceed this at Fukushima.) In October 2008 Tepco accepted 1000 Gal (1.02g) DBGM as the new Ss design basis for Kashiwazaki Kariwa, following the July 2007 earthquake there.


    In March 2011 eleven operating nuclear power plants shut down automatically during the major earthquake. Three of these subsequently caused an INES Level 5 Accident due to loss of power leading to loss of cooling.

    Anyone who has seen the video of the plant post-earthquake and tsunami would note that the plant to survived the initial two disasters intact but failed nonetheless. It's well publicised that the explosions that destroyed the reactor buildings were from a hydrogen build up but not why there was a hydrogen build up and where that much hydrogen came from.

    A reactor is a machine with design issues, refered to as Basis Design Issue or Design Basis Issues, that are mitigated by safety systems and procedures implemented to reduce the risk of these design issues becoming the vector for a disaster. The General Electric and Hitachi Reactors had two BDIs that had to be mitigated by safety systems.

    The first Basis Design Issue of the General Electric reactor comes from the tests of the reactor prototype by the American Society of Mechanical Engineers in Brunswick in the 1970's. During the test the reactor was to be pressurised to 72psi, yet it only reached 70psi no matter how much more it was pressurised. This indicated that the reactor was leaking gas. Thus as the moderator in the reactor vessel got lower hydrogen gas was produced and leaked when the internal pressure reached 70psi. This was the first source of hydrogen.

    The second BDI revolves around the spent fuel cooling pools. Due to the nature of the refueling gate pairs that separate the reactor head from the spent fuel containment. The design of the seals on the gates require them to be constantly powered to prevent a loss of coolant. There is a pool volume of 1300 tons of water and they are 12 meters deep. There is 850 tons of water above the spent fuel in each except for reactor 1 spent fuel pool which is smaller by 400 tons. There is 60 Million calories per hour heating capacity in the spent fuel rods in reactor 1 spent fuel pool, 400Mcal/h in reactor 2 spent fuel pool, 200 Mcal/h in reactor 3 and 1600 Mcal/h in reactor 4. Had those spent fuel containment pools not leaked there should have been several *months* to do something. However it seems the scenario that unfolded was *exactly* in line with what would happened if plutonium in those spent fuel pools was exposed, hydrogen was produced and conditions for a serious explosion were in place.

    What is known is that to mitigate these two risks an availability of a constant supply of electricity is a requirement for a reactor facility. So why wasn't it? As is known the reason is that the tsunami took out the back-up power and the cooling pumps for the reactor. This, I believe, is the first piece of evidence for negligence on the part of TEPCO.

    The [pdf warning] Regulatory Guide for Reviewing Seismic Design of Nuclear Power Reactor Facilities [] categorises react

  • by Animats ( 122034 ) on Tuesday April 12, 2011 @12:22PM (#35795106) Homepage

    The inexcusable part of all this was the hydrogen explosion. Explosions. That's the cause of all the structural damage. The reactor buildings survived the earthquake and tsunami.

    That's a known, expected problem. It was a big worry at Three Mile Island, but they managed to avoid it. It is preventable. There are catalytic recombiners [], passive devices which recombine hydrogen and oxygen non-explosively. Many nuclear plants have them, but pre-TMI plants usually don't. If those had been retrofitted in the decades since TMI, this would have been a much smaller disaster. See this IAEA paper, "Mitigation of hydrogen hazards in water-cooled power reactors". [] They indicate that passive recombiners are necessary, and are in use in Germany, France, Canada, the United States, and Russia. They've been retrofitted to the GE Mark I reactor in other countries. But not, for some reason, in Japan.

    The cooling pumps survived the earthquake and tsunami, and continued to run until the battery backups ran out. The hydrogen explosions probably damaged them and their plumbing and wiring. (Nobody can get through the wreckage and radioactivity yet to tell. A remote-controlled backhoe/grab and a dump truck are now being used to dig through the rubble.) If it hadn't been for the hydrogen explosions, restoration of power would have restored reactor and fuel pool cooling.

    So that's where TEPCO screwed up. They failed to install a low-cost standard protective device that's been used elsewhere for decades.

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