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Power Japan The Courts

Japanese Court Rules Against Restarting Ohi Reactors 75

AmiMoJo writes: "A Japanese court has ordered the operator of the Ohi nuclear plant in Fukui Prefecture, central Japan, not to restart two of its reactors, citing inadequate safety measures. The plant's No. 3 and 4 reactors were halted for regular inspections last September. Local residents filed a lawsuit asking that the reactors be kept offline. They said an estimate of possible tremors is too small, and that the reactors lack backup cooling systems. The operator, Kansai Electric Power Company, has insisted that no safety problems exist."
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Japanese Court Rules Against Restarting Ohi Reactors

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  • Re:Godzilla! (Score:3, Insightful)

    by Anonymous Coward on Thursday May 22, 2014 @01:48PM (#47068443)
    That failure took the combined effort of one of the largest earthquakes ever recorded AND a massive tsunami. Even if the safety measures in place were deemed 'adequate' they would never be able to stop that. The safety measures in place have worked fine in that country for the better part of a century, this is overreacting on the grandest scale.
  • Re:Godzilla! (Score:5, Insightful)

    by imikem ( 767509 ) on Thursday May 22, 2014 @02:13PM (#47068767) Homepage

    How many people has the nuclear power industry killed exactly? For extra credit, compare against coal which has had to pick up the missing supply in Japan.

  • Re:Godzilla! (Score:4, Insightful)

    by knightghost ( 861069 ) on Thursday May 22, 2014 @02:16PM (#47068781)

    Once-a-century disasters are something to plan for. There was a host of badly designed pump systems - and business processes. It's not unreasonable to fix them given the cost of their expected failure.

  • Re:No problem (Score:2, Insightful)

    by Anonymous Coward on Thursday May 22, 2014 @02:25PM (#47068867)

    which is why it's safe in theory - not in practice.

  • Re:Godzilla! (Score:2, Insightful)

    by ShanghaiBill ( 739463 ) on Thursday May 22, 2014 @02:49PM (#47069117)

    How many people has the nuclear power industry killed exactly?

    If you include Chernobyl, it has killed quite a few.

    compare against coal which has had to pick up the missing supply in Japan.

    Sure, but nobody is seriously proposing coal as a long term solution. Japan is an island nation in the tradewind belt. All major cities are close to both mountain ridges and offshore sites that would be ideal for wind turbines. So what happens when the wind stops? I have been to Hokkaido, and it never stops.

  • Re:Godzilla! (Score:5, Insightful)

    by chmod a+x mojo ( 965286 ) on Thursday May 22, 2014 @03:14PM (#47069347)

    The major thing leading up to the meltdowns was human error, both in the emergency generator rooms / power conduits not being waterproofed, and the decisions regarding what to do with the reactors during an emergency situation. There were other plants that had gotten swamped, but did not suffer meltdowns, all due to waterproofing the emergency generator rooms; If I remember correctly one plant that was swamped and survived had quite literally finished the waterproofing only a few weeks prior.

    Not only that, but the reactors most likely could have been saved even after the tsunami hit. The problem was the operators ( rightly, or wrongly ) were too afraid to depressurize the reactor vessels so passive low pressure emergency cooling measures could operate, these would have lasted long enough to get pumps and / or generators on site. This decision not to depressurize was due to public fear of "wah, small amounts of short lived Iodine and and noble radio gasses would escape with the steam" mentality and lead directly ( unknown at the time. the operator actions were quite reasonable and understandable - it is only hindsight that tells us what the best action should have been ) to the larger scale and broader spectrum radio-isotope release.

  • Re:Godzilla! (Score:3, Insightful)

    by chmod a+x mojo ( 965286 ) on Thursday May 22, 2014 @05:57PM (#47070583)

    This is absolutely false. While there may have been some functionality of the system left after the tsunami, it was not designed to operate under those conditions and it those limited functions were not available for very long, and therefore was not effectively operable is any reasonable sense.

    You should review your sources, there are several factual errors in play here.
    1: The low pressure emergency cooling was not damaged, it was fully functional but not used. The emergency coolant was available, and the heat sinks were also available. No external power would have been needed, these systems are gravity fed and designed as a last redundancy for situations where every other option failed. The reason this system was not used was mainly fear of radio-gas release and point 2.
    2: it is the fault of the operators for every decision they made. They made the decision to blindly trust what they should have know were ( potentially, and in this case literally ) compromised sensor units and did not due any physical checks. I don't have the papers in front of me, but I believe it was unit #1 that actually melted first due to a stuck valve ( maintenance issues, not tsunami issues) and not dumping steam to the suppression ring and subsequently boiling dry within 6 hours. This should have been noticed if there had been physical checks of the systems. Sensors also indicated water levels that where meters higher than actual, again physical checks(temps and volumes of steam blow-off) and some simple math would have shown closer to true estimates - Decay heat should have been roughly 10-12% of full power generation, and the known volume of water in the vessel + loops can tell you the kJ's of heat being put into the water by how much water was being turned to steam / hour and at least estimates of how much water SHOULD be in the condensers VS how much water really WAS in the condensers. The first real reactors we had used less instrumentation to run than what they had available.
    3: There are also other logical fallacies in your argument: You can never make anything "proof" against another force, only resistant. If something is not "proof" against the other force it shouldn't be built? We should never build anything then, we can't make it large space object impact proof.
    As for the Fukushima daiichi plant, it was quite resistant to the tsunami, the reactors + reactor buildings themselves did not sustain significant damage until the actual meltdown and hydrogen explosions. It was only the emergency generators that really weren't up to snuff ( and there WAS power available from units 5-6 which had functional generators, just no easy way to route cable to units 1-4 through the muck and debris ) Again see points one and two for how this could, and in an ideal situation should, have been able to prevent the catastrophe.

    Does this mean that there could / should have been more done? Of course more should have been done, both France and India sent out reports to the whole nuclear community detailing swamped emergency generator rooms over a decade prior to the Tohoku-Oki event, the very reason most other plants had waterproofed their generator rooms and survived relatively unscathed. I said specifically that this was part of the human error in the disaster.
      I can't comment on the plant being built on higher ground because I don't know the reasons why the particular place it was built had been chosen, but higher seawalls may have helped, but may not have. As far as my research has shown, for this area of Japan this was a freak occurrence. There was some evidence that other areas on the coast had seen tsunami events this large, but nothing concrete until data from this tsunami actually correlated to suspected paleo-tsunami evidence. Maybe we will find out that this magnitude event does impact the coast there more often, in that case it is true it should not have been built there; but that is using post fact data.

"I prefer the blunted cudgels of the followers of the Serpent God." -- Sean Doran the Younger