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Japan

Why Tokai No. 2 Nuclear Power Plant Survived March 193

Kyusaku Natsume writes "In a potentially damning report, the Japanese government panel probing the Fukushima Daiichi meltdown has learned that the nuclear power plant Tokai No.2 avoided station blackout thanks to making a 6.1 m high seawall, but TEPCO failed to do the same in Fukushima. From the article: 'The tsunami that hit the Tokai plant on March 11 were 5.3 to 5.4 meters in height, exceeding the company's earlier estimate but coming in around 30 to 40 cm lower than its revised projection. After the tsunami hit, the Tokai plant lost external power just like Fukushima No. 1 did, because the sea wall was overrun, knocking out one of its three seawater pumps. But its reactors succeeded in achieving cold shutdown because the plant's emergency diesel generator was being cooled by the two seawater pumps that survived intact.'"
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Why Tokai No. 2 Nuclear Power Plant Survived March

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  • Huh? (Score:4, Informative)

    by fluffy99 ( 870997 ) on Monday October 24, 2011 @11:05PM (#37827480)

    Someone want to translate the summary? Or is this to be more evidence of lousy content and even worse editting? "as learnt" really?

    • Re:Huh? (Score:5, Informative)

      by chiasmus1 ( 654565 ) on Monday October 24, 2011 @11:12PM (#37827520) Homepage
      Translation:

      Researchers: Your walls are too low.
      Japan Atomic Power: Oh, okay, we'll fix the wall.
      Tokyo Electric Power Company (TEPCO): Hmm, whatever.

      Then the tsunami came. Japan Atomic Power's wall was good enough. TEPCO's wall still was not good enough.
      • Re: (Score:3, Interesting)

        It is not that easy. Reactor no2 in Tokai mura came closer to disaster than anyone wants to admit. Two pumps may have survived, but only one generator (out of three) was working. Had it failed, the result would likely have been similar to Fukushima. That being said. It is my impression (as someone living in the vicinity) that Japan Atomic Power is running things a lot more responsibly than TEPCO. But then again the TM power plants used to be under direct control of JAEA, and JAP was created only when J
      • Re:Huh? (Score:5, Funny)

        by quenda ( 644621 ) on Tuesday October 25, 2011 @01:16AM (#37828146)

        Translation from original Japanese:

        2009:
        Researchers: Somebody set up us the seawall.
        Japan Atomic Power: Main wall turn on.
        Tokyo Electric Power Company (TEPCO): All our time are belong to us.
        2011:
        Researchers: You have no chance to survive make your time.
        Tokyo Electric Power Company (TEPCO): For great justice.

      • by rtb61 ( 674572 )

        Not to forget. Nuclear power companies, do not rely on pumps for cooling. Pumps should supply cooling reservoirs and gravity should be used to water for cooling purposes.

        The capacity of cooling reservoirs should equal the required the time required to replace those pumps upon failure and maintain cooling demands, whether achieving shut-down or full load requirements.

        Yes it costs more to do it that way but it is still significantly cheaper than failure of the system. Laws definitely need to be changed t

        • Re:Huh? (Score:4, Insightful)

          by thegarbz ( 1787294 ) on Tuesday October 25, 2011 @03:08AM (#37828572)

          Not to forget. Nuclear power companies, do not rely on pumps for cooling. Pumps should supply cooling reservoirs and gravity should be used to water for cooling purposes.

          The capacity of cooling reservoirs should equal the required the time required to replace those pumps upon failure and maintain cooling demands, whether achieving shut-down or full load requirements.

          Yes it costs more to do it that way but it is still significantly cheaper than failure of the system. Laws definitely need to be changed to make corporate executives legally and criminally liable for the decisions they make. When those decisions kill they should be charged with man slaughter and spend the appropriate extended time in prison.

          And thus you have fallen into exactly the trap that got them into the position they were in.

          The power was out. There was a bigarse battery bank to keep things going. But guess what, thepower was out because an earth quake and a tsunami basically screwed the nation and backup generators which could normally easily be sourced and commissioned within a day or two couldn't.

          When your reservoir runs out of water you better hope there's someone more senior than you there to take the resulting beating.

          The engineering solution is not to propose some contingency to counteract some ludicrous event, it's to prevent the event from happening in the first place and put the pumps in a place not so easily hammered by a wall of water.

          • Re:Huh? (Score:5, Insightful)

            by JasterBobaMereel ( 1102861 ) on Tuesday October 25, 2011 @06:22AM (#37829260)

            ..the real trap is: Don't run a nuclear power plant beyond it's design life, and don't continue running it when it has failed several inspections

            The reason the sea wall was not higher : It cost too much

            The reason the plant was not upgraded : It cost too much

            The reason the plant was not replaced : It cost too much

            • by vlm ( 69642 )

              I'm astounded at how little relationship this has to reality, other than what happened was bad, and what you list sounds also sounds bad.

            • by AmiMoJo ( 196126 )

              The problem is that nuclear power is just not commercially viable, so there will never be enough investment. The UK designed and built reactors and was once leading the world, all government owned and paid for. In the 1980s the government sold off power stations to private companies, but no-one would touch the nuclear ones because the running, maintenance and clean-up costs were too high. That is after all the development, building and fuelling costs had been paid.

              If we want nuclear power we are going to ha

              • Nuclear power is definitely commercially viable which can be seen in the many plants running around the world safely and for profit, as well as the many projects in some countries to build new ones.

                Nuclear power is not viable depending on HOW you run it, or HOW you legislate it. In the litigious society of the USA you'd be mad to propose building a nuclear reactor. In less litigious societies they are quite commercially viable due to the sheer scaling of the technology and the ability to generate many gigaw

                • by afidel ( 530433 )
                  Of course running a nuclear plant is cheap if you can externalize risk....
                • by sycodon ( 149926 )

                  Technologically and legislatively speaking, Nuclear Power is stuck in its infancy, R&D cut off at the knees by the anti-nuke crowd and pandering politicians refusing to consider updating and enhancing the legal frameworks governing nuke plants.

                  I would suggest:

                  1. Encourage the development of smaller, modularized that could be factory built and delivered.
                  2. Periodically select reference designs that would be pre-certified and then protected legislatively from endless challenges by the anti-nuke crowd.
                  3. W

              • The UK's Nuclear power stations are three types, experimental/Military grade, which the costs of decommissioning were never considered at all, PWR (Sizewell B) - American design, and our own design AGR's which are most of the ones operating today in the UK

                The majority of these have less than 10 years operational life left, and the decommissioning costs where largely unknown when the sell off was done and the commercial investors ran scared ...

                France generates 78% or it's electricity with nuclear, and export

            • You're attacking this from the wrong angle. The goal is not to build a wall higher at some ludicrous cost, the goal is to think ahead and design a plant so that water spilling over the wall doesn't have the effect that it had. Look elsewhere in the comments to find plenty of examples of things that could have been done on the cheap which would have prevented the disaster escalating from what could have been just a emergency shutdown of a powerplant.

          • by JSBiff ( 87824 )

            Maybe the real solution is, perhaps, that all plants should be designed to, in the worst case scenario, *meltdown gracefully*.

            One such design is a Liquid Fluoride Thorium Reactor - technically it always operates melted down, and in an emergency, the molten fuel salt just drains into a cooling tank that allows the molten salt to cool off passively into the surrounding environment. There's no water in the LFTR design, so you don't have to worry about high pressure radioactive steam being vented, nor about hyd

        • The capacity of cooling reservoirs should equal the required the time required to replace those pumps upon failure and maintain cooling demands, whether achieving shut-down or full load requirements.

          Substitute boron carbide/boric acid slurry for the cooling reservoirs and you might have an answer.

          • by vlm ( 69642 )

            Doesn't help at all with residual heat. That is the solution if you have no working control rods, which was not the problem.

            It would seem a heck of a lot simpler to require building the thing below sea level and having the piping for thermosiphon operation.

        • Unfortunately, negligent executives contain (on average, in rough figures) only about 40 liters of coolant each, with vigorous squeezing. Unless your organization is grotesquely over-managed, it is unlikely that you can solve the problem by those means alone...
        • by Luckyo ( 1726890 )

          Fun detail: as far as we know, no one died as a result of the fukushima (outside one worked who fell down to his death or something similar - clarify this point if you have more info). Over 30k died as a result of tsunami.

          Who do we throw in prison for tsunami?

        • by Andy Dodd ( 701 )

          So, since people fight the construction of new plants tooth and nail - how do you propose they do this?

          All of the design improvements you state have already been made. But people fight construction of new plants (even if it is to replace old ones), resulting in old clunkers like Fukushima staying in service.

          You do realize that Unit 1 at Fukushima was one of the oldest operating reactors on the planet, and was originally supposed to start the decommissioning process days before the quake but received a serv

    • Someone want to translate the summary? Or is this to be more evidence of lousy content and even worse editting? "as learnt" really?

      I think you should be a bit more understanding when an article has likely been submitted by someone who is not a native English speaker.

    • And we're not due foresight from folks who transmute elements for money, because money corrupts. The first thing money corrupts is expectations.
    • by MrKaos ( 858439 )

      Someone want to translate the summary?

      TEPCO fucked up,,bad.

    • Re:Huh? (Score:5, Funny)

      by Kyusaku Natsume ( 1098 ) on Tuesday October 25, 2011 @01:43AM (#37828250)

      Someone want to translate the summary? Or is this to be more evidence of lousy content and even worse editting? "as learnt" really?

      I am the one that submitted the story, but I found my mistake until I saw the story posted. English is my third language. I'm sorry, I will buy everyone a pack of Ned Flander's eye soap.

      • English is my third language. I'm sorry, I will buy everyone a pack of Ned Flander's eye soap.

        Don't worry, we forgive you. Just try to be more careful next time.

        Remember, there are no editors here to do basic fact checking and proof reading.

      • by LWATCDR ( 28044 )

        Not a problem but the Slashdot editors should have fixed that error and frankly this factual error.
        "But its reactors succeeded in achieving cold shutdown because the plant's emergency diesel generator was being cooled by the two seawater pumps that survived intact.'"

        Odds are that they diesel generator was not cooled by the two remaining seawater pumps but that the reactor reached cold shutdown because the diesel generator powered the two remaining sea water pumps that provided cooling to the reactor.

        But ple

    • Someone want to translate the summary? Or is this to be more evidence of lousy content and even worse editting? "as learnt" really?

      Really. "learnt" is actually correct in this place, even though in the USA you're trying to get rid of these more sophisticated verb forms.

  • by the_raptor ( 652941 ) on Monday October 24, 2011 @11:38PM (#37827680)

    What I want to know is why the secondary coolant pumps were housed in tin sheds instead of say a concrete bunker like the primary reactor buildings?

    I had just assumed for all these years that something as important as the secondary coolant system would be protected by more then some steel panelling. If they had of placed the secondaries in a concrete bunker on the side of the primary reactor building opposite the ocean then it would take a disaster big enough to crack the reactor building to put them out of commission.

    It would probably end up cheaper then building a sea wall.

    • by Graff ( 532189 )

      What I want to know is why the secondary coolant pumps were housed in tin sheds instead of say a concrete bunker like the primary reactor buildings?

      The generators that run the pumps require venting to operate and even if they had piping for the venting it would still be difficult and costly to build a watertight seal around them. We're not talking about a couple of kilowatt generators here, these are fairly bulky installations.

      What you do instead is place them behind walls or on top of high points that would place them out of reach of a anticipated reasonable high-water mark. This is a risk vs reward assessment that should take into account the serious

      • by mysidia ( 191772 ) *

        The generators that run the pumps require venting to operate and even if they had piping for the venting it would still be difficult and costly to build a watertight seal around them.

        Backup generators don't require the venting until they are actually being utilized however.

        They could be in a nearly watertight concrete bunker capable of having venting through openings in the bunker.

        With maximal independent protection of each individual backup generator until an emergency failure of the primary occu

        • by vlm ( 69642 )

          If there's one thing I've learned about diesel generators in over a decade in the telecom business, its that a diesel that isn't run to full operating temp and full load power on a regular basis (like, weekly?) simply will not run ever again. You'll find it faster (although not cheaper) to install a new gen rather than diagnose and replace the damaged / rusted / failed parts.

          Now installing extremely hardened facilities to drop a new gen in place might be a valid good idea... A solid reinforced concrete pie

          • If there's one thing I've learned about diesel generators in over a decade in the telecom business, its that a diesel that isn't run to full operating temp and full load power on a regular basis (like, weekly?) simply will not run ever again. You'll find it faster (although not cheaper) to install a new gen rather than diagnose and replace the damaged / rusted / failed parts.

            That's why standards (e.g. NFPA) relating to generators for life-safety require periodic load tests.

            Now installing extremely hardened facilities to drop a new gen in place might be a valid good idea... A solid reinforced concrete pier for a air cooled gen on a barge? (Can't use water cooling after a tsunami, water is all full of "stuff"). Solid steel and concrete railroad siding with some extreme gadgetry to hook up a diesel electric to the plant. Even just a bulldozer accessible road and platform with cabling pre-run to the platform?

            But you CAN use seawater (river water, lake water, etc.) for cooling-- you just need to keep the clean, treated cooling water in a closed loop, separated from the "other" water by a heat exchanger.

        • by AmiMoJo ( 196126 )

          That is in fact how newer plants are set up. Waterproof generator building with a supply of fuel.

          Even so there is a danger that you will run out of fuel before reactor shutdown is complete. Fukushima has six reactors and the amount of diesel they would have to keep on site to shut down all of them is vast and itself presents a hazard.

      • by JSBiff ( 87824 )

        "and even if they had piping for the venting it would still be difficult and costly to build a watertight seal around them."

        Buh, wha? Haven't you ever seen the chimneys on an old ship? They shape them like candy-canes, so that water would have to go UP the chimney.

        So, you build the generators in a rugged, water-tight building, run some chimneys (both fresh air intake, and exhaust) up nice and high, far higher than any tsunami will ever possibly get (or so high it would be an extinction event in the area any

    • Perhaps an elevated reinforced concrete platform is sufficient, 5m? Keep it simple?
  • A 6m, or even a 12m sea wall would not have helped. The only thing damning about this is the summary.

    • by ColdWetDog ( 752185 ) on Tuesday October 25, 2011 @12:29AM (#37827912) Homepage

      A 6m, or even a 12m sea wall would not have helped. The only thing damning about this is the summary.

      From TFA

      Although Tepco calculated in 2008 that tsunami higher than 10 meters could hit the nuclear plant — a height close to the actual waves seen on March 11 — it only reported its calculation to the Nuclear Industrial Safety Agency on March 7, 2011.

      I don't recall the wave height to have been measured with any degree of accuracy. However, if the sea wall was 12 meters high and the tsunami actually 15 meters high, the barrier would have significantly reduced the amount of over run. If you watched the video of the wave hitting Fukashima, you saw a brief leading edge slam into and overrun the sea wall, then a mass of water that was not as high. It is certainly possible that the higher wall would have significantly limited the damage.

      • Not only that, TEPCO know at least since 2002 that they needed to improve their tsunami defenses in Fukushima Daiichi, they had 9 years to do the necessary steps. Tokai 2 still had troubles because they didn't finished their countermeasures, but at least their management shown a better understanding of what was at stake than TEPCO.

      • However, if the sea wall was 12 meters high and the tsunami actually 15 meters high, the barrier would have significantly reduced the amount of over run. If you watched the video of the wave hitting Fukashima, you saw a brief leading edge slam into and overrun the sea wall, then a mass of water that was not as high. It is certainly possible that the higher wall would have significantly limited the damage.

        No, it wouldn't have. A Tsunami is not like a normal wave. Water would have poured over the sea wall for 15-30 minutes, so it would have risen just as high with the sea wall. A sea wall that is 1ft lower than a tsunami height is of little use, one of 1m-5m lower be of no benefit at all.

        • by Splab ( 574204 )

          Wont a 1 ft. too short wall mitigate the impact of the wave? It's quite obvious that a total flooding will occur, but wet concrete is surely better than smashed concrete?

    • That's why I put the "potentially" at the beginning. TEPCO will need to explain why even if they know for so long that their countermeasures were insufficient they didn't take any action. The credibility of the company was already low with their fake safety reports, they don't need to appear even more negligent to the japanese public.

  • by palmer.dabbelt ( 1801614 ) on Monday October 24, 2011 @11:59PM (#37827796)

    [Cut to: Ships Cockpit. The room is flooded with red light and the message "Danger" repeatedly flashes on the screens. Bender snores loudly. Enter Fry and Zoidberg.]

    Fry: What's happening?

    [Zoidberg turns on another screen that displays the extent of the damage to the tanker. There is a huge gash most of the way along the hull. A gauge at one side of the screen drops as the dark matter levels go down.]

    Zoidberg: All 6,000 hulls have been breached!

    [Fry falls to his knees.]

    Fry: Oh, the fools! If only they'd built it with 6,001 hulls! When will they learn?

  • inapt comparison (Score:5, Interesting)

    by 0WaitState ( 231806 ) on Tuesday October 25, 2011 @12:01AM (#37827802)

    Fukushima had multiple hardware failures, correctable design problems, and crappy management. The failure was not just due to a low seawall.

    1. Reactor 1's cooling system likely failed due to the quake, not the failure of the backup diesels. This opinion is based on analysis of the remaining sensors, that indicated the reactor was having problems even while the battery-powered cooling was still running. The existing plumbing and wiring had been embrittled from 4 decades of operation in a quake zone and proximity to, well, a nuclear reactor.

    2. Design flaw and hardware failure: locating the backup diesel generators in a basement under the reactors, such that they were guaranteed to flood if water entered the area.

    3. Design flaw: locating the spent fuel pools directly above the reactors in the same buildings, such that if the reactor had a little problem (hydrogen explosion, or moderated prompt criticality), said fuel would get blown sky-high, which it did in the reactor 3 explosion.

    4. Design flaw: no externally located terminals for "connect portable generators HERE", and no rationalization of Japan's two different electrical standards (it's a fucking nuclear power plant that will blow up if not cooled, so support both standards, guys).

    5. Management failure: All reactors should have been flooded with seawater immediately after the quake, as soon as the situation on the ground at the site became clear. This might have averted the hydrogen explosion by keeping the reactors cool enough to not oxidize the zirconium fuel-rod cladding. Local personnel correctly identified the situation, remote management denied permission to flood the reactors with seawater (because that basically ends the reactor's productive life). Eventually a local guy did so anyways.

    • Re:inapt comparison (Score:5, Informative)

      by MrKaos ( 858439 ) on Tuesday October 25, 2011 @01:16AM (#37828150) Journal

      Fukushima had multiple hardware failures, correctable design problems, and crappy management. The failure was not just due to a low seawall.

      The Basis Design Issues of the Mk1 GE reactors ( the Hitachi and Toshiba reactors were based on that design) were known and neither of the two were correctable.

      1. The evidence for the 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 where it was revealed in the tests of the reactor prototypes that vented when the reactor reached 70psi internally (they tested it with air).

      2. A General Electric Nuclear reactor of that design requires a constant supply of power due to the nature of the refueling gate pairs that separate the reactor head from the spent fuel containment. I understand that, due to the nature of the seals on the gates, they need to be constantly powered to prevent a loss of coolant.

      These BDIs are mitigated when a reactor is operated according to the Seismic Design Criteria for Nuclear facilities, S and B class facilities (those that contain radionuclides (S) or attached to pressure vessels that contain radionuclides (B) ) should not be affected by the loss of a C class facility (a support facility like a backup generator). The actual quake measured around 140Gal at Fukushima but the plant was designed to tolerate 600Gal (S class). As evidenced the C class facilities (diesel generators) were not as they were affected by the quake, and B class facilities (the pumps) were inundated by the tsunami indicating at least two obvious cases of negligence that led to the loss of the facility.

      Clear cut case of criminal negligence on TEPCOs part. Further evidence is in the amount of heat in the spent fuel in the cooling pools. There is a pool volume of 1300 tons of water, 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.

      The failure mode for a loss of coolant event in those spent fuel pools was *exactly* in line with what would happened if plutonium in those spent fuel pools was exposed, hydrogen was produced and an explosion occurred. That is what happened. Without those spent fuel containment pools leaking there should have been several *months* to do something, ergo the reactors were operating out of spec. This analysis is based on the available data and it seems a clear cut case of criminal negligence, because the facility survived the initial catastrophes. The risk could have been mitigated years earlier but it wasn't.

    • by cyn1c77 ( 928549 )

      Fukushima had multiple hardware failures, correctable design problems, and crappy management. The failure was not just due to a low seawall.

      1. Reactor 1's cooling system likely failed due to the quake, not the failure of the backup diesels. This opinion is based on analysis of the remaining sensors, that indicated the reactor was having problems even while the battery-powered cooling was still running. The existing plumbing and wiring had been embrittled from 4 decades of operation in a quake zone and proximity to, well, a nuclear reactor.

      2. Design flaw and hardware failure: locating the backup diesel generators in a basement under the reactors, such that they were guaranteed to flood if water entered the area.

      3. Design flaw: locating the spent fuel pools directly above the reactors in the same buildings, such that if the reactor had a little problem (hydrogen explosion, or moderated prompt criticality), said fuel would get blown sky-high, which it did in the reactor 3 explosion.

      4. Design flaw: no externally located terminals for "connect portable generators HERE", and no rationalization of Japan's two different electrical standards (it's a fucking nuclear power plant that will blow up if not cooled, so support both standards, guys).

      5. Management failure: All reactors should have been flooded with seawater immediately after the quake, as soon as the situation on the ground at the site became clear. This might have averted the hydrogen explosion by keeping the reactors cool enough to not oxidize the zirconium fuel-rod cladding. Local personnel correctly identified the situation, remote management denied permission to flood the reactors with seawater (because that basically ends the reactor's productive life). Eventually a local guy did so anyways.

      It sounds like there was only one major flaw.. they didn't spend enough money constructing and maintaining their safety systems.

      But I am sure they enjoyed profiting from skimping on maintenance in the years before the earthquake!

    • by AmiMoJo ( 196126 )

      In future they are talking about shutting down coastal reactors as a matter of course after a large earthquake. The tsunami took 45 minutes to reach Fukushima and with active cooling a lot could have been done in that time. Before there was concern that the loss of generator capacity would cause power shortages but since Japan has been forced to ration power for months due to 95% of reactors being offline the general feeling is that the loss is acceptable.

    • by vlm ( 69642 )

      4. Design flaw: no externally located terminals for "connect portable generators HERE"

      Connector design at the multi megawatt level is not very well understood by the general public. You're not really saving any time by pre-running the last 50 feet of extension cord, so to speak.

      Best you can hope for is pre-running some cables from the flooded and smashed switchboard in the basement to the ... oops thats not gonna work because of the smashed and flooded switchgear. Well assuming the switchgear was intact, you could run a cable to some "portable gen" location. Unclear what that would be, si

  • Bairly survived (Score:3, Interesting)

    by TheInternetGuy ( 2006682 ) on Tuesday October 25, 2011 @12:16AM (#37827872)
    It may have survived, but it did so hanging on by a hair. The article only mentions the pumps, but in fact two of the three diesel generators were also out of order. Which means this could easily have turned real bad really fast.
    Quoting Wikipedia. http://en.wikipedia.org/wiki/TC5%8Dkai_Nuclear_Power_Plant#Incidents [wikipedia.org]

    Following the 2011 Tohoku earthquake and tsunami the number 2 reactor was one of eleven nuclear reactors nationwide to be shut down automatically.[4] It was reported on 14 March that a cooling system pump for the number 2 reactor had stopped working.[5] Japan Atomic Power Company stated that there was a second operational pump and cooling was working, but that two of three diesel generators used to power the cooling system were out of order.[6]

    Also it remains to see if the reactor will survive politically. The Mayor of Tokai Mura has called on the government to decommission the number 2 reactor which is over 30 years old. There is a population of over one million people living within a 30km radius of the plant. And they have lost their confidence in the governments ability to safely run the plant. The well known Tokai Mura critically accidents a number of years ago probably didn't do much to boost their confidence either.

    • by dbIII ( 701233 )

      Also it remains to see if the reactor will survive politically.

      It was all over years ago.
      Large power plants (especially nuclear ones) take a very long time to build, and time spans over a decade have been quite usual. Since nothing of this type has been built for so long in Japan and nothing is planned now the industry is on life support until it's eventual expiry when the existing plants get old (and consequently damaged) enough that they are too expensive to maintain. Problems with Japan's economy signe

      • by AmiMoJo ( 196126 )

        In the past Japan funded development of expensive technology by exporting it, e.g. high speed rail. Interest in nuclear power decreased decades ago as the full costs (including spent fuel storage and site clean-up) became apparent, and the future is clearly renewable now so that is where the investment is.

    • I hadn't heard of the first Tokai Mura incident, so I consulted Wikipedia. For the curious, here is the link:
      http://en.wikipedia.org/wiki/Tokaimura_nuclear_accident [wikipedia.org]

  • by tp1024 ( 2409684 ) on Tuesday October 25, 2011 @02:28AM (#37828448)
    There is one simple way that would have prevented the tsunami from taking out all emergency generators.

    To comply with international standards and have at least four emergency generators per reactor placed around the reactors with adequate spacing between each of them to prevent common cause failure. For purely geometric reasons (to keep the distance between each other) at least one per reactor would have to have been behind the reactor buildings on higher ground. Which exactly how spacing alone mitigates common cause failure.

    It would also have been helpful had TEPCO installed Passive Autocatalytic Recombiners in their reactor buildings to catalytically "burn" the hydrogen before it can reach combustible or explosive concentrations. (Those do their job by hanging on the wall. No power required.) Or if they had hardened and filtered containment vents.

    Both of those measures were implemented in Sweden, Germany and France some time after the analysis of the Three Mile Island accident, which quite accurately predicted how Fukushima Daiichi turned out, which was deemed unacceptable. Hence the additional safety features. I'm not saying that those are the only countries that implemented such measures, but with those I'm sure. And I stopped making assumptions about those things seven months and two weeks ago.
    • To comply with international standards and have at least four emergency generators per reactor placed around the reactors with adequate spacing between each of them to prevent common cause failure. For purely geometric reasons (to keep the distance between each other) at least one per reactor would have to have been behind the reactor buildings on higher ground. Which exactly how spacing alone mitigates common cause failure.

      This bears repeating to all you engineers and designers out there. If you calculat

      • by vlm ( 69642 )

        That goes precisely against the mentality and compensation plans of the entire industry.

        A poorly run plant is defined as a plant that has a 4-gen availability uptime of 99%. (slightly made up number)

        A well run plant is defined as a plant that has a 4-gen availability uptime of 99.99% (slightly made up number)

        Management is paid for the goal of improving from 99% to 99.99% which is best done by putting all the gens in the same spot so the mechanics have easy access to all four, at the same height so they don'

    • by vlm ( 69642 )

      Or if they had hardened and filtered containment vents.

      Hydrogen doesn't explode below about 1% concentration. Solution is obvious, once the H2 explosions start, smash a hole in the roof.

      The legal system there and nuclear training is somewhat like a doctors "first do no harm" training here. Once H2 explosions started, I knew all the buildings were going to pop with H2 explosions, because "first do no harm" means they can't get themselves to do make a hole in the roof to let the H2 escape; it must explode inside the building.

  • Try Google Scholar:

    http://scholar.google.de/scholar?q=Containment+Hydrogen+Control+and+Filtered+Venting+Design+and+Implementation&hl=de&as_sdt=0&as_vis=1&oi=scholart [google.de]

    You will find that the first page contains only results between 1979 and 2003. This has nothing to do with hindsight. In fact, lots of people had the foresight to implement such measures. TEPCO was not among them.

For God's sake, stop researching for a while and begin to think!

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