Tepco: Unable to activate backup cooling system at No. 4 fuel pool

Published: June 30th, 2012 at 1:39 pm ET
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30 comments


Subscription Only: Cooling system for Fukushima Daiichi No. 4 reactor suspended
Kyodo News
June 30, 2012

The cooling system for the spent fuel pool at the crippled Fukushima Daiichi power plant’s No. 4 reactor automatically suspended operation Saturday, Tokyo Electric Power Co. said.

The utility known as TEPCO has been unable to activate a backup cooling system for the pool and is looking into the cause of the trouble, officials of the plant operator said later in the day

[…]

See also: [intlink id=”just-in-kyodo-no-4-cooling-system-stopped-after-alarm-tepco-leakage-of-water-with-radioactive-materials-has-not-been-confirmed” type=”post”]{{empty}}[/intlink]

Published: June 30th, 2012 at 1:39 pm ET
By

30 comments

Related Posts

  1. Kyodo: No. 4 Spent Fuel Pool’s cooling system stopped after alarm sounds — Tepco: “Leakage of water with radioactive materials has not been confirmed” June 30, 2012
  2. Kyodo: Tepco to try and get No. 4 fuel pool cooling system running again Sunday June 30, 2012
  3. Kyodo: Possible Leak at Unit No. 4 — Spent fuel pool cooling system halted after alarm sounds April 12, 2012
  4. Tepco: Cooling system back on at Spent Fuel Pool No. 4 July 1, 2012
  5. WSJ: Temperature rising at No. 4 fuel pool — Safety limit to be exceeded Tuesday morning? June 30, 2012

30 comments to Tepco: Unable to activate backup cooling system at No. 4 fuel pool

  • norbu norbu

    sound's like trouble, what are they going to do? What is the temp now? Hope they do not have the day off today.

    • BreadAndButter BreadAndButter

      Hi norbu,
      "The water temperature of the pool was 31 C at the time of the suspension at around 6.25 a.m."

    • charlie3

      iwas worried about SP4 collapsing, but I suppose SP4 heating up and burning up in the air in an intact building is just as bad for us and the earth. What an unedning, always-threatening nightmare. We've got this Sword of Damocles hanging over our throats forever until it eventually slays us all.

  • TheBigPicture TheBigPicture

    Challenges like this will be happening on a continuous basis for decades and decades. Cancer causing radiation will be spewing nonstop as well.

  • Gaffney

    18 hours since this happened. We know from previous times that the temperature increases at a predicted 0.5c but on average has actually been 1c per hour.

    The temperature of the pool was 31c so now it should be between 40c to 49c. The safety limit is 65c which at a rate of 1c will be reached in 16 hours.

    An educated guess is that if the temperature reaches 85c then the water will be boiling at the bottom and the fuel rods could start degrading. I'm not sure how long at 85c before there is any potential for the rods melting through the pool.

    • Gaffney

      Although there might not be any danger of a melt through unless there is very little/no water left in the pool. They did just recently put a cover on the pool, that would probably increase the rate of temperature increase and make air drops impossible.

      • norbu norbu

        Right, with cover on can not get to it, how crazy.

        • BreadAndButter BreadAndButter

          I remember the cover was put on by a crane in one piece. So I think it would be possible to remove it quite quickly, if necessary.

          • Gaffney

            I forgot it's just been placed on and not welded. One issue I can still see is the crane won't be able to lift off if it's windy because they big cranes aren't suited for winds over 20mph.

  • norbu norbu

    Just great, not really, are they working to restore the cooling system? If it start's to melt how long before it reaches the common pool, or will it not cause a reaction between them?

  • BreadAndButter BreadAndButter

    The bottom of the pool consists of 180 cm concrete, the side walls 140 cm, according to Tepco.

  • norbu norbu

    will 5'10" of concreticus hold back all that heat?

  • norbu norbu

    I agree. Let's say they fix the cooling system.

  • GeoHarvey

    A quote for the day:
    “A lot of people think that Fukushima is behind us, in fact it’s ahead of us.” This was from Jean-Christophe Niel, head of ASN, the French nuclear safety authority.

    • BreadAndButter BreadAndButter

      He's right, I'm afraid:
      Kyodo says cesium was found in urine of 6.9% of children tested in Fukushima:
      "A small amount of radioactive cesium was found in the urine samples from 141 infants and young children living in Fukushima Prefecture, where the crippled nuclear power plant is located, among 2,022 of those surveyed, a Japanese research group said Saturday.
      Three urine samples contained more than 10 becquerels of cesium per kilogram, including a case with 17.5 becquerels. Ten becquerels or less of cesium was found in the samples of the other 138, the Yokohama-based Isotope Research Institute said.
      The urine samples also contained about an average 64 becquerels of radioactive potassium."
      http://english.kyodonews.jp/news/2012/07/166838.html

      *is anyone testing their blood / bones???

    • charlie3

      That's the first honest and intelligent thing that I have heard from a nuclear official since this disaster began.

  • patman

    In the absence of any agitation, any vapour pockets/air bubbles clinging to the hot surfaces would provide localized insulation from cooling water contact, until those bubbles break free.

    Heating and evaporation of cooling water would drive up dissolved solids content and make the remaining cooling water foamy.

    Not sure how effective silicone based anti-foam solution would be in that case. Silicone based anti-foam would combine with dirt and become a fouling agent with high temperature stability. Silicone based anti-foam may also be quite insoluble in water after it's surfactant has been degraded by heat, reducing the efficiency of cooling water after circulation is reestablished.

  • I find the choice of words curious. Maybe "suspended" sounds like they have some control, where "failed" does not?

  • razzz razzz

    Gee, I wonder if the deconstruction of the Unit 4 building has anything to do with SFP recirculation loop shutting down again?

    Vibrating debris and concrete dust would be enough to disturb the pool causing a mixing in the water to form a nice slurry to clog the pumps and overwork the electric drive motors and/or any inline filters.

    I take it two pumping systems are down, the primary and the backup.

  • chrisk9

    You have a spent fuel pool that has had a crane dropped into it, one or two fires, molten fuel at the bottom, and who know what kind of water put into it. There are all kinds of materials that pumps and values would not like at all. So having problems should be expected. In normal operation the water has almost zero impurities, and that is what it is designed for.

    They can add water from somewhere even if both pumps are inoperable. It might not be filtered or high quality water, but they must have sources. This almost seems like a non story, because there are answers. Why are they passing out disturbing news when there is some kind of answer. As each day passes they appear to be bigger and bigger idiots. If I am wrong about another source of water then i have underestimated their idiocy.

    • richard richard

      @chrisk9 – get used to their idiocy. I've been watching it daily since about 12/03/11.

      They are criminally inept at tepco, the Japanese guberment is o different.

      There are clear conflicts of interest between what is right for the people and the environment, and the profits of the mob.media.corp.guv

      Tepco is the keystones cops and three stoogers wound into one, and the life of planet earth is in their foolhardy hands.

      They need to be removed from the site and replaced by a responsible team of unbiased experts.

      But the whole nuke industry is corrupt to the core. The jap.gov is corrupt. The media is corrupt and the USA guberment is extremely corrupt.

      Now we have enenews, because many of us watched as these lying mongrels have brought us all closer to death. We need to fight and win the info war. And we need to stop the entire nuke industry. Else we are all dead. We probably are already, but justice needs to be delivered at the very least.

      /end rant

    • vivvi

      Even if there IS suitable water available, how do you propose they get it a hundred feet up in the air without using pumps? This is BAD.

    • charlie3

      I no longer underestimate TEPCO's incomptence.

    • dharmasyd dharmasyd

      Not to Worry! TEPCO … is looking into the cause of the trouble!"
      Yikes.

  • horndoggie horndoggie

    "then i have underestimated their idiocy."

    don't feel bad, I seem to do it weekly….

  • razzz razzz

    It would be a non-story if TEPCO didn't use Murphy's Law as their working motto.

    • chrisk9

      The one law we could always count on when I worked at these plants. Murphy's Law was in force daily. That and FUBAR.