APR: your source for nuclear news and analysis since April 16, 2010

Sunday, April 3, 2011

Further updates...

DEVELOPING at 7:15 Eastern or about 8:15 Tokyo time... TEPCO has begun using colored dye powder in various water pools and sources at the No. 2 plant to confirm the routing of the contaminated water leakage. We'll keep an eye on that, as it is a positive step toward figuring out the complex interrelations that now exist between bodies of water in places they should not be, interrelating in ways they also shouldn't be able to due to cracks and failed pipe seals.

Apparently there is consideration being given again to surrounding the reactor buildings with new structures that would then be draped with some sort of fabric that would theoretically contain the contamination. Our initial reaction: Bad idea.

Further details as available, hopefully including some new plant parameters.

7:30 PM Eastern Sunday 4/3
ATOMIC POWER REVIEW

7 comments:

  1. The effort to block the outlet of the radioactive water is incomprehensible to me.
    Obviously there is piping damage to some reactor lines and radioactive material is escaping.
    Sure it is better to pump up this material into some containment such as the recently used fresh water barge than to block the outlet and have it back up into the structure.
    The effort to block this source of pollution could make the site lethal to humans fairly quickly, if the reports of a 500 ton/day volume are correct and if the indications that the air above the outlet registers over 1000 millisieverts.
    Is there a plausible explanation of this effort? It seems irrational as is.

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  2. @netudiant: The only motivation I can think of is that one of the two things absolutely necessary to end the accident control / mitigation phase is to end release of contamination to the environment. TEPCO is trying desperately to cap a flow of contaminated water that's in a place it has not been planned or designed against, and is having to improvise on the spot as it were. Unfortunately for them the other thing necessary to end this is to ensure the core is cool, contained and stable and the fact is that the flow of water needed to do this is directly related to the volume of effluent now entering the ocean. Since TEPCO cannot afford to cut down cooling water much more (we have seen several times what happens when they try this) they must hurry to cut off the flow of the contaminated water to sea in parallel with developing ways to store what water does get out of the reactor primary system. Frankly, the situation is overall well outside any DBA analysis I've ever read and TEPCO is certainly doing everything possible given the exceedingly difficult circumstances they find the plants, the site, and the personnel in.

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  3. Seen that the airborne contamination continues unchecked and may even increase as the reduction in cooling water results in higher temperatures and more iodine and cesium boil off, the focus on this waterborne pollution seems unbalanced.
    Capturing the outflow would seem the obvious thing to do, although it surely would be the hardest job yet in what is already a nightmare project.
    It is astonishing that the effort is on such a small scale, fewer people om site than at Dai Ni. It might be helpful to compare this to the number of people working on TMI during that incident.

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  4. The proliferation of MacGiver style suggestions would be amusing if this were not a global health emergency. It does demonstrate the fallability of the techno dweebs when something like real life interferes with their "design basis" scenarios. Yes, things can go wrong, sometimes quite badly. Given enough time they will go wrong because we are human, not perfect machines.

    So the lesson is don't put your energy generation bets on a technology that can quite easily contaminate hundreds of square miles of countryside. Don't use a system that needs constant cooling or it will melt down. Avoid depending on equipment that must be operated by remote control and, when it malfunctions, cannot even be approached by humans without lethal effects. Don't use a system to boil water that is completely inimical to biological life and generates wastes that will be deadly for thousands of years.

    Geez.

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  5. Presumably there must be an injection point between the pressurised reactor and the leaks? They could just pump in concrete. So it seems they want to save the turbine hall cooling systems. I just do not get that. Already they are talking about several months to stop the main leaks. Installing alternate cooling or routing to existing cooling elsewhere makes more sense given the hazards they are faced with in the existing building.

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  6. netudiant, you say "airborne contamination continues unchecked" but the evidence as I understand it (eg. from overflights) is that airborne contamination has been very much reduced. Unless you have better evidence.

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  7. Afaik, the airborne emissions from the site are produced from the damaged spent fuel pools that are open to the air and that are steaming.
    There has been no independent measurement of these emissions to my knowledge, nor even a statement by any regulator, research institution or military entity that sizes the scale of the plume. The announced measurements have all been of depositions, which depend on the vagaries of the wind and precipitation.

    This Austrian site monitors the spread of the plume using the CNTBT data network http://www.zamg.ac.at/

    However, their data is only by extrapolation from a fairly sparse network, so it has high uncertainty,
    around a factor of 1000 according to their estimates.

    Any other sources for emission measurement would be very much welcome.

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