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Japan Power News

Japan Battles Partial Nuclear Meltdown 769

Hugh Pickens writes "Japanese nuclear experts are working to contain a partial meltdown at an earthquake-stricken nuclear power plant north of Tokyo, as fears grow that the death toll from Friday's massive quake and tsunami could reach the tens of thousands. A partial meltdown, experts said, would likely mean that some portion of the reactors' uranium fuel rods had cracked or warped from overheating, releasing radioactive particles into the reactors' containment vessels. Some of those particles would have escaped into the air outside when engineers vented steam from the vessels to relieve pressure building up inside. Adding to problems at the site, hydrogen was building up inside the Number Three reactor's outer building, threatening an explosion like the one that blew apart the Number One reactor building's roof and outer walls on Saturday. However, it remains unclear how far radiation has spread from the facility. Some local residents and health workers were diagnosed with radiation poisoning in precautionary tests, but they show no outward symptoms of distress. 'Even if you have a radiation release, although that's not a good thing, it's not automatically a harmful thing. It depends on what the level turns out to be,' says Steve Kerekes, a spokesman for the Nuclear Energy Institute, a US industry group, adding that a person exposed to the highest radiation levels measured at the Fukushima site would absorb in two to three hours the same amount of radiation that he would normally absorb in 12 months – a significant but not necessarily injurious amount, especially if exposure time was short."
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Japan Battles Partial Nuclear Meltdown

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  • Re:Considering ..... (Score:5, Informative)

    by Anonymous Coward on Sunday March 13, 2011 @10:16AM (#35470902)

    Indeed. I'm this guy [], an irrelevant mathematics graduate with postgrad focus on the history of science and mathematics (so I'm not a nuclear power station worker but I'm not completely uneducated in the topic).

    I tried to prompt a discussion on the Greenpeace blog about their sensationalist - and, especially yesterday, entirely unsubstantiated - banner.

    My contributions were removed.

  • by maxume ( 22995 ) on Sunday March 13, 2011 @10:28AM (#35470996)

    3 of the 6 reactors at the facility were offline for inspection, so there is some chance that they will be able to bring them back up on a decent schedule.

    Doesn't really change what you describe, but maybe keeps it to months.

  • by iserlohn ( 49556 ) on Sunday March 13, 2011 @10:28AM (#35471000) Homepage []

    Nuclear is also among the most expensive power generation methods available. I'm not sure what the potential upsides are.

  • Good technical info (Score:5, Informative)

    by wjwlsn ( 94460 ) on Sunday March 13, 2011 @10:32AM (#35471028) Journal

    The following document is a good source of info regarding the situation at the Fukushima reactors. See the section titled "BWR 3/4 Perspectives", including the parts regarding station blackout (SBO), transients with loss of coolant injection, and transients with loss of decay heat removal (DHR). (The remaining parts of the BWR 3/4 section don't appear to apply.)

    Core damage frequency perspectives for BWR 3/4... []

  • Re:what progress? (Score:5, Informative)

    by siddesu ( 698447 ) on Sunday March 13, 2011 @10:40AM (#35471084)

    There is no lack of information in Japan. There has been 6 or 7 press conferences on the topic by the management of the power station today, both before and after every development that happened at the station during the day. All the conferences had a pretty reasonable technical explanation of the steps, and report upon execution. All conferences were broadcast fully on several TV channels.

    There are three problems with the coverage. First, western media have been extremely sensationalist in their coverage. Second, journalists, both in Japan and in elsewhere ignore the presentation (e.g. one journalist complained that she doesn't understand the explanations, and that there isn't "enough information" in the same breath on live TV), and press with "hard" questions, which end up to be only one: "When is this shit going to explode?". Three, which is a failure of Tepco, they put forward people who cannot explain shit eloquently. The explanations make sense if one listens patiently and makes sense of a ton of stuttering, stammering, repeating, verbal mistakes. Of course it ain't working when every journalist has to tweet within 25 seconds of the start of the explanation.

    Finally, the big problem in Japan now is getting help to the people in the affected areas, not the meltdowns in Fukushima that may, or may not be happening.

    But I guess some journalists have to make a living.

  • by Megane ( 129182 ) on Sunday March 13, 2011 @10:43AM (#35471120) Homepage

    It's not getting much press, but the Unit #1 reactor was scheduled to be closed [] in two weeks. [] (Those links don't show the exact date, but I think it was March 22.)

    It's sort of like the old cliche about a cop getting shot in the month before his retirement.

  • by Anonymous Coward on Sunday March 13, 2011 @10:45AM (#35471134)

    These are reactor designs from the 1960s. Green opposition has successfully stopped the development of newer and safer control systems, so we are left with 50-year old technology to resist the largest earthquake/tidal wave ever seen in Japan.

    Nevertheless, the reactor technology worked, and shut down the reactors. Then the water damaged the support services which were cooling the reactors down, meaning that they had to get permission to vent short-lived radionuclides in an unsafe manner. They did this - one site was unlucky enough to get an aftershock as they did it, which precipitated a hydrogen explosion in an unmanned part of the reactor building. There was one death and 4 light injuries. By now the reactors will all be cooling down, and there will be no more incidents.

    In the meantime the gas and oil refineries, with the benefits of the latest technology, caught fire and exploded, causing many deaths. The sea defences were overrun, causing MANY THOUSANDS of deaths. But the headline news is about whether the reactor fuel rods have got slightly overheated....

    I think the press has its priorities wrong....

  • Why not to worry (Score:5, Informative)

    by NieKinNL ( 690492 ) on Sunday March 13, 2011 @10:52AM (#35471186)
    Dr Josef Oehmen, a research scientist at MIT, has written his take [] on the events, and why he's not worried about it.
    I haven't finished reading this story yet (it's quite a few pages), but it's pretty interesting so far.
  • by sycodon ( 149926 ) on Sunday March 13, 2011 @10:57AM (#35471228)

    Fast breeder reactors can burn that waste leaving material with a half life of mere decades.

  • by Anonymous Coward on Sunday March 13, 2011 @11:22AM (#35471420)

    Fast breeder reactors can burn that waste leaving material with a half life of mere decades.

    And nuclear proliferation and a bunch of other isotopes and other things which have half lives far from "mere decades".

    Quite realistically, the best way forward as I see it, is to develop LFTR technology.
    It'd be particularly beneficial in earthquake prone areas as the molten salts would cool and go subcritical and end the main reaction.

    For more info, see: International Thorium Energy Organisation []
    Energy from Thorium has a nice piece about the current situation in Fukushima Daiichi. []
    LFTR in 16 minutes - for those who are time poor. Explains why you're on Slashdot. []
    Wikipedia - for those who want citation, please. []

    Yes, IAANP

  • Re:Considering ..... (Score:5, Informative)

    by vadim_t ( 324782 ) on Sunday March 13, 2011 @11:28AM (#35471468) Homepage

    You're talking of kilowatt hours, I imagine. In that case, it'd take about 12 hours to generate that much. The amount you say you use sounds very small, and could be quite easily generated by a solar panel if you have a roof for it.

    That said, I have no clue where's he's getting his number from, as that'd be one big roof.

  • by Sprouticus ( 1503545 ) on Sunday March 13, 2011 @11:45AM (#35471616)

    In a day to day sense, nuclear power is almost as cheap and FAR cleaner than oil. Have you ever lived near an oil refinery? Much less a well? I used to pass one every week going to and form work. It smelled, and left a smile on your car if you stayed more than a few hours. How safe can THAT be to live near. Here is aquick report. I cant speak the the numbers but it gives you a good idea of the impact. []

    I worked on a naval nuclear reactor while in the Navy. I was a chemistry and RadCon tech. I understand the science and risks better than you do. Sorry if that sounds eilitist, but its true. Just because radiation is involved does not mean it is evil.

  • by Anonymous Coward on Sunday March 13, 2011 @11:46AM (#35471622)

    Actually you are wrong on two counts.

    Firstly, the fissile and fertile uranium in enhanced burn-up reactors are in much much greater concentration than they are in uranium deposits in the ground, and uranium deposits are pretty diffuse. There's lots of arsenic, mercury and lead in the ground, too. That does not mean that you want to concentrate tonnes of arsenic or mercury and dump it into any old hole in the ground. You almost certainly especially don't want to dump it back into one of the holes you extracted it.

    Secondly, by assembling a reactor pile that goes critical (i.e., it maintains a self-sustaining chain reaction), you really are creating radiation that would not occur naturally (except in very very rare and small cases like the Oklo natural reactor). Although you can literally dump a bunch of fissile-uranium-and-carbon in a heap -- a literal pile -- and have it go critical, by careful engineering with one of several possible fast-neutron-to-thermal-neutron moderators, you can produce many more nuclear disintegrations whose daughter products trigger more nuclear disintegrations, in a chain reaction. Carefully surrounding the pile with concentrated isotopes will in turn produce ("breed") fissile material that can be used in building a new pile.

    In short, it is moving around the fissile materials (and fertile ones, and unfortunately a whole host of building and other secondary materials which will, under neutron or gamma bombardment, themselves become radioactive) that creates the relevant radiation. It is not a concentration of radiation at all, but rather most of the radiation is a side-effect of concentrating a sufficient amount of suitable material (mostly material that was already slightly radioactive on its own) into a _critical mass_.

  • by ScrewMaster ( 602015 ) * on Sunday March 13, 2011 @11:52AM (#35471668)

    It's cleaner because all the waste is concentrated - in solid form, to boot - and there aren't any carbon emissions beyond those resulting from the construction of the plant.

    Now you, like me, might not feel that CO2 should count as unclean when it comes to these sort of statistics but most people apparently disagree.

    Yes, and when comparing it to coal, you have to understand that coal fields are naturally radioactive. Burn it, and those radioactive substances (thorium, for one) are now air pollution.

  • Re:what progress? (Score:5, Informative)

    by turgid ( 580780 ) on Sunday March 13, 2011 @12:07PM (#35471778) Journal

    "Containment domes" are not a silver bullet.

    There are many factors (as you might expect) that contribute to nuclear safety. The most important is the design of the nuclear reactor. It's very difficult to make a poor design "safe" and a containment dome isn't always possible or useful. For example, gas-cooled reactors could not have containment domes.

    The RBMK (Chernobyl) design is intrinsically unsafe from a nuclear physics point of view, as demonstrated by the accident in 1996. Additionally, the safety systems were poor and able to be vetoed (very bad) and the reactor was being run out of its design specification and by people who didn't understand Reactor Physics. In fact, their attitude was one of superstition: the reactor has been good to us in the past, so it'll be good to us today.

    Here in the UK there were great changes in the way our nuclear power industry was run following the Chernobyl disaster. The legal framework for the industry was completely overhauled, the way we operated our reactors was radically changed and all of our safety cases and fault studies were revisited, re-analysed and our plant refitted with extra redundant, diverse and segragated safety systems. All of our personnel, from the company directors to the plant operators were retrained.

    We are lucky in that most of our reactors are of the gas-cooled variety (AGRs with formerly some Magnoxes). They are pretty intrinsically safe designs, but not perfect. Explosions and meltdowns are either "incredible faults" or highly unlikely. The most likely event that could lead to an offsite release of radioactivity for Magnoxes was a channel fire. At the commercial stations, this never happened. There was one once at Chapel Cross (used to make isotopes for military purposes in addition to electricity) but there was no release from the affected reactor, and they were able to refuel and continue using it.

    The concrete pressure vessel stations (AGRs and the two youngest Magnoxes) could not "explode" (burst open). They are too strong: no tertiary containment (containment dome) required. They can't go prompt critical (i.e. no Chernobyl) because of the reactor physics and safety systems. If you tried to do one manually, the reactor would be shut down automatically long before it even got a bit too hot.

    We won't be building any more AGRs, though. EDF will probably be building some based on the PWR design in the next few years. PWRs are OK as long as you have plenty of redundant and segregated cooling loops. I think the new ones will be able to post-trip cool on natural convection, so no power required for emergency cooling.

    As for your original point, as long as the Russian RBMKs have their safety systems fixed (unable to be take out of service) there should not be another Chernobyl. Another thought: I don't know if these plant have boric acid for emergencies. For water-cooled reactors (e.g. PWR) it is a requirement to have a load of boric acid that can be dumped into the primary coolant to ensure permanent shutdown in the case of an emergency. Boric acid dissolves in the water and the boron absorbs all the neutrons. shutting down the nuclear reactions. It's a permanent shutdown though :-) The Magnoxes had boron dust that could be injected into the coolant gas for such an emergency.

  • by iserlohn ( 49556 ) on Sunday March 13, 2011 @12:22PM (#35471898) Homepage

    Did you read the whole page? The only (levelised) study that shows nuclear to be competitive it the UK study (and only by a relatively small margin). In everything else, nuclear trails on-shore wind.

  • Citation needed. On the other hand, here's a citation of my own: Nuclear power is Hooked on Subsidies []. And China, France, India, and Russia do not have the US's lawyers or environmental laws.


  • by Cyberax ( 705495 ) on Sunday March 13, 2011 @05:01PM (#35474288)

    Russia has one working power-generating breeder reactor ( [] ) and another one under construction.

    So it's certainly possible, but up until now not cost-effective.

The relative importance of files depends on their cost in terms of the human effort needed to regenerate them. -- T.A. Dolotta