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

Monday, April 18, 2011

Monday early afternoon update

The plant status at Fukushima Daiichi is, at the moment, quite stable... and it's refreshing to note that there have been no sharp changes in plant status or remotely indicated figures in quite a few days.

Readers might, given this, wonder why I'm making a post. I have two points to make.

1. The rad levels discovered by the robots inside the reactor buildings are NOT surprising, contrary to some press reports, given the condition of the reactors. Much higher levels have been encountered in previous accidents.

2. Many, many press outlets are already using the term "sarcophagus" for the enclosures planned by TEPCO. Readers here know better. There will be two phases of enclosure; first, a fabric type enclosure on steel framing that will prevent aerial release of contamination, and later a concrete and steel building surrounding the original (damaged) reactor buildings. This second enclosure will provide weather protection to workers dismantling the plants, and prevent any further spread of contamination.

It is important to note that the press is trying to imply - wrongly - that TEPCO intends to permanently surround / bury the plants and leave them alone. This could not be more incorrect.

Two groups of firms - one comprised of Toshiba, Westinghouse, Babcock & Wilcox, and The Shaw Group, and the other comprised of Hitachi, General Electric, and Bechtel, have offered competing plans to not only defuel the reactors but have the site cleared .. that means plants demolished .. in ten to fifteen years.

It's imporant to understand the difference between temporarily placing a plant in a storage status, which here in the US by NRC terms is called "SAFSTOR" and leaving a plant to decay permanently as it seems Chernobyl-4 will. The Fukushima Daiichi site will eventually be cleared of the plants and associated equipment, at least above ground.

1:25 PM Eastern Monday 4/18
ATOMIC POWER REVIEW

4 comments:

  1. Hi Will,
    Have you seen this PDF? Shows how they pump water into the spent fuel pool and that (part of?) it comes out via skimmer tank and a "water discharge" - one wonders where this is stored or flowing to...
    Patrik

    http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110418e5.pdf

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  2. @patrik: Yes, I've seen that. That line is only for use when you want to lower that level in the skimmer tank; it is not meant to imply that there's a continuous discharge. I think the red text on the drawing is meant to imply that those connections are only used as needed, ie to raise or lower level.. or in other words to increase or decrease water inventory.

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  3. Are there any cost and time estimates yet to get the fuel removed and the site cleared?

    Will units #5 & 6 ever operate again? If they don't what is the magnitude of the lost investment?

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  4. Yes, there are; see several recent posts as to the time estimates.

    No, they won't; see the post from about 8:30 AM local time on Sunday wherein TEPCO reveals they'll defuel 5 and 6. TEPCO cannot worry about loss of investment now with the disaster they have on their hands, both environmentally and in the public eye. We knew this site would never see nuclear generation again and said so weeks ago. The public would never allow it, and frankly from an operational standpoint it would be totally impossible with the scale of the accident on-site to try to operate those two plants.

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