Fukushima Daiichi - probable high radiation exposures of workers

[Yo_Mama]

http://phys.org/news/2013-09-fukushima-pipe-leaking-radioactive-tepco.html

The likely explanation of the Level 3 designation for the water leak was that radiation exposures of multiple workers amounted to, or were likely to amount to, "deterministic effects". We don't know that yet, but the manual does boot it to a Level 3 when you start getting workers with very high levels of exposure.

The latest info makes my theory here a lot more plausible:

The operator of Japan's stricken Fukushima nuclear plant said Sunday it had found highly radioactive water dripping from a pipe used to connect two coolant tanks, patching it up using tape.

The discovery of the pipe came a day after Tokyo Electric Power Co (TEPCO) said it found new radiation hotspots at four sites around coolant tanks, with one reading at 1,800 millisieverts per hour—a dose that would kill a human left exposed to it in four hours.

As of July, TEPCO was not reporting any high exposures to workers. Yet perhaps the explanation is that the methodology used has an upper limit, or perhaps higher exposures occurred in August:
http://www.tepco.co.jp/en/press/corp-com/release/betu13_e/images/130830e0201.pdf

In any case, the significance of the last two months is that there are increasing dangers to worker safety at the plant, and they are hard to mitigate. The leaking pipe they just found was measured at 230 milliSieverts an hour. You have workers now in this area constantly trying to monitor the situation, and the fact that they are finding acute radioactive areas means that the situation becomes more problematic.

http://www.ft.com/intl/cms/s/0/954e56a4-12e8-11e3-804f-00144feabdc0.html#axzz2ddv1Nazk
http://online.wsj.com/article/SB10001424127887324886704579048362546754326.html

I am not one of the alarmists on this site, but I find attempts to minimize the current situation utterly insane.

[darkangel218]

1. There was a nuclear apologist on here a few days ago

Who claimed everything is stabilized over there Obviously I knew it wasn't true, it just amazes me the lenghts they go to, just to defend their precious reactors.

How do these people sleep at night?

[Yo_Mama]

2. I have been accused multiple times of being a nuclear apologist at this site

But I am not - I just stick with the facts. There have been many claims of risks at Fukushima Daiichi that were not based in reality, such as melted cores still plowing into the ground.

But THIS is very real. And anyone who has ANY comprehension of the situation has got to realize that a serious problem is emerging.

The 1.8 Sievert hotspot implies that there was a leak at that spot, probably slow, and that the water evaporated and left concentrated highly radioactive particles behind. And it is apparent that TEPCO hasn't been surveying this site as it should, and now any work in the area should proceed first with a fine-grained survey of the work area to find such exposures.

[darkangel218]

3. Ohh, im pretty sure Tepco has been surveying the site.

They just chose to hide the actual data, in the hope the world will forget about it.

Its sickening

[Yo_Mama]

4. No, they haven't

Not like this. They didn't even have water level monitors on these tanks.

They don't have the manpower. They don't have the money. The current claim quoted in at least one article is that they missed this hotspot earlier because they were using detection equipment that only went up to 100 millisieverts. This may not be correct, but it would not be the first time TEPCO has done this, so it's not impossible.

My concern is that the workers at the plant are being exposed to growing risks, and that their methodology for evaluating worker exposure is flawed.

Further, this sort of finding is highly problematic. Right at that area they measured 1.8 sieverts. This is extremely lethal. But if you walked through this area with a radiation monitor 10 yards away, you'd get a much, much lower reading.

And they don't know how this specific area became so contaminated, so it may be that there are other highly contaminated spots in the storage facility. It's also at least possible that the bottom of the tank is corroded and that water is dripping slowly out.

TEPCO doesn't know what is going on, which is a very dangerous situation. They don't have the ability to remove the water from this site.

Something needs to change very significantly and rather quickly.

[darkangel218]

5. So you trust Tepco??

[Yo_Mama]

6. I don't think they are lying

I do think that the situation is out of their control, that they do not have the resources to deal with it, and that the company and government culture is such that there is no honest public discussion of the risks. I doubt that there is even a behind-the-scenes honest discussion of the risks.

I think they bull ahead doing the best they can as they have been doing since the disaster struck with the resources they have.

TEPCO is really bankrupt. Funds for this effort have been primarily coming from special bank loans mandated from the government and guaranteed by the government.

I don't trust TEPCO to deal with the plant, I don't trust TEPCO to ensure the safety of the workers, and I am absolutely sure that TEPCO will not be able to handle the cleanup by itself. But I also believe that this entire situation is a political hot potato, and that the Japanese government prefers to have TEPCO nominally handling the situation so that they can have someone to point to. Well, that's got to end. The Japanese government needs to officially take over decision-making and planning. Without that there will never be accountability.

[wtmusic]

7. What kind of priority would you assign to the current situation?

Here is most recent TEPCO report on the incident of worker contamination:

"-At around 10:35 AM on August 28, an associated company worker, who had been working on water transfer of the H4 area tanks in Units 1-4, received a contamination examination at the Main Anti-earthquake Building after the work, and was found to have contamination on the head, face and breast. Therefore, the worker was instructed to receive whole body counting. Then, the contaminated parts were cleaned by wiping, etc., and the contamination level became dropped below 13,000cpm (equivalent to 40Bq/cm2) set as the screening level. Accordingly, at 2:51 PM on the same day, the worker left from the Entrance Area Management Buildings. Note that the worker received smear measurement on the nasal and oral cavities, which showed no contamination. However, the worker was found to have some contamination (5,000cpm) on the head, and therefore, received whole body counting on August 29, which showed that the worker has no internal intake."

http://www.tepco.co.jp/en/nu-news/2013/1230165_5484.html

What do you consider a "very high level of exposure"?

The hot pool was described as being 3 meters x 3 meters x 1cm, or .1 cubic meters in volume, it's been cleaned up, and it came from a tank of RO concentrated water (at higher radionucleide concentration than the water coming from the reactor building).