Thursday, May 19, 2011

TEPCO Discloses Details of #Fukushima I Reactor 2 Entry: "Too Hot and Humid to Work for More Than 15 Minutes"

40 degrees Celsius, humidity over 90 percent (in the previous survey by the robots). 50 millisieverts/hour radiation, and the Spent Fuel Pool is apparently very warm.

At one spot, the steam (highly radioactive) from the Spent Fuel Pool was condensing and falling like raindrops. But TEPCO says it will be easier to work in the Reactor 2 than in the Reactor 1, because the radiation is lower. 50 millisieverts/hour sure seems infinitely lower than 1,000 or 2,000 millisieverts/hour in the Reactor 1.

(Take a look at the photos that the workers took, in my previous post. Link opens new window.)

From Nikkei Shinbun (5/19/2011):

 東京電力は 19日、福島第1原子力発電所2号機の内部を調べた詳細を発表した。原子炉建屋内は温度と湿度が高く「体力の面から15分以上の作業は困難」と説明した。 放射線量も最大で毎時50ミリシーベルトだった。新しい工程表では1~3号機の原子炉を「循環注水冷却」の新方式で冷やすとしたが、作業が難航する可能性 が出てきた。

TEPCO disclosed the details of the survey of the interior of the Reactor 2 reactor building [done on May 18]. According to TEPCO, the temperature and humidity were too high for the workers "to work for more than 15 minutes". The radiation level was also high, at 50 millisieverts/hour at the maximum. In the revised "roadmap", the reactors 1, 2 and 3 are to be cooled with the external water cooling systems, but the condition inside the reactor buildings may jeopadize the work [outlined in the "roadmap"].

 18日午前に作業員が中に入り調査した。建屋内には水たまりが3カ所あった。東電は「使用済み核燃料プールからの蒸気が建屋内で冷え、小雨のようにしたたり落ちているところがあった」としている。

Workers entered the Reactor 2 reactor building in the morning of May 18. There were three water puddles inside the building. According to TEPCO, "there was one spot where the steam from the Spent Fuel Pool condensed inside the building and was falling like small raindrops."

 入り口から奥に向かうに従い、温度が上がり長時間の作業は困難だ。以前にロボットを使った調査ではセ氏約40度を計測した。

As the workers proceeded from the entrance, the temperature rose, making long works impossible. In the previous survey using the robots, the temperature registered 40 degrees Celsius.

 東電は記者会見で「放射線量は毎時1千ミリシーベルトが計測された1号機と比べると、湿気の問題が解決すれば作業はしやすい」との見方を示した。プールを冷ます装置を取り付けるほか、換気も検討するとした。

Nonetheless, TEPCO was of the opinion that "it would be easier to work in the Reactor 2 reactor building as long as the high humidity can be dealt with, than to work in the Reactor 1 reactor building where the radiation level was measured at 1,000 millisieverts/hour". TEPCO said it would install a system to cool the Spent Fuel Pool, and come up with some form of ventilation.

What's left unsaid by the article or TEPCO is the now-admitted fact that the Containment Vessels of these reactors are damaged and leaking. How could they construct a cooling system that would circulate water that leaks from the RPV into the Containment Vessel back into the RPV, if the Containment Vessel is leaking? Could they fix the leak?

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Mainichi Shinbun (link is in Japanese) says one worker in his 40s fell ill after the work inside the Reactor 2 reactor building, and was treated for heat exhaustion.

7 comments:

Anonymous said...

Areva,

With all that is happening and the revelations, I wonder if you could help to write article on:
1. what happens now for those living out of Fukushima, particularly in Kanto area? Not much news other than they are finding more plants contaminated. I doubt it's just tea leaves at this point, right?
2. do we still have risks of explosions as a result of the meltdowns, aka. China Syndrome? if yes, what would be the magnitude? I can't seem to find info on this anywhere.

Thanks for taking the recommendation, you can't tell how appreciate I am of what you are doing.

Hélios said...

Hello,
Some links, if you dont know them.
http://zardoz.nilu.no/~flexpart/fpinteractive/plots/?C=M;O=D
http://globalcooperative.wordpress.com/2011/05/18/radiation-map-analysis-europe-australasia/

For France, now, it's OK, (some readers of my blog keep watch on measures with Geiger counters and convey every day.)
http://bistrobarblog.blogspot.com/

Anonymous said...

1. The characteristic pattern you will see on maps of radiation is "leopard spots".
They will be finding radiation hotspots for years to come. It will lead to odd situations, where, say, crops from one rice paddy will need to be treated as radwaste, while the neighboring cabbage patch will turn up clean.

Testing MUST be stepped up and kept up, on the entire island at least, because the radioactive Cesium is quite mobile, it gets dissolved in water, goes up as fog, back down in rain etc.
My advice to you, if you live in Japan: do what you can to help with testing, screening and education.

Organize a buyers' co-op to screen farm produce. Get a detector and go hotspot-hunting in your neighborhood on weekends. Get active in the political arena, try to make labeling the origin of food mandatory.

Get informed, most importantly. Inform others, but ONLY when you feel you have sufficient grasp of the subject matter. Radiation safety is not very complicated, but it's easy to scare people out of their wits.

2. Stop it with the China syndrome already. It's Chile, anyway, not China.

No matter how deep the corium is right now, in the three reactors, it is being cooled. It will be hot for a year or even more, so they will continue to pour water and make radioactive steam.

If we're lucky, they should be able to direct that steam to some condensers, some time in August and the worst of the airborne pollution will stop.

Explosions from corium hitting water will almost certainly not happen, they would have happened already. There may still be explosions and fires from hydrogen or from the corium igniting something or maybe even from electrical equipment left outdoors, in the monsoon). All these would spread some more radioactive pollution.

Oh, btw. This is most important. Operate in yourself a change of mindset. It is not "radiation" you are fighting. It is pollution.

You are not in danger to drop dead from prompt beta+gamma due to massive fallout. You are in somewhat elevated risk of cancer from pollutants in the environment. These pollutants happen to be easier to detect than mercury or dioxin. You only need a Geiger counter to do an initial assessment.

Sure, it gets complicated when you want to find out what exactly is in there, but for keeping safe, a detector and some care in selecting food sources is adequate for risk mitigation.

Oh. One more thing. Plants are able to use some of the radiation - it's just light, after all. They tend to grow bigger than usual because of this extra light. If you see a radish twice normal size in the market, don't buy it.

rosethorn said...

Radioactive iodine from Fukushima Daiichi a threat to unborn children

Exposure to I-131 causes significant increase in infant mortality.

Anonymous said...

Of all the risks associated with TEPCO's power plant there is one that I have not seen any discussion of and that is the problem of wild animals be they bird, fish, mammal or reptile.

In the early days after the 3/11 disaster there were reports of birds dining on fish stranded on the grounds of the Fukushima power plant by the tsunami. These birds would have been flying through the worst radioactive plumes, roosting on the shattered reactor building structures or landing amongst the debris to feed. This situation presumably continuese to this day.

Other creatures such as rodents, animals that prey on rodents, lizards, stray domestic cats and dogs even flies and insects have had free access to buildings and grounds of Fukushima Daichi. Fish in the surrounding waters have been swimming in highly radioactive waters and some may have died, washed ashore and have been eaten by gulls and other scavangers. These creatures are not static. They are quite mobile and could end up many miles from the official contaminated zone.

Consider a person living many miles from the affected area coming out in the morning to find a seagull has left its droppings on his car. The victim of the aerial fecal bombardment goes and gets a paper towel to wipe the mess off his car not knowing that that bird may have been very radioactive! Have the authorities given any thought to this or do they consider it not a serious problem?

Anonymous said...

Robbie001 sez:

I cover the animal contamination subject in a past post that magically disappeared during the last purge. Unfortunately Fukushima isn't the only place where animals are contaminated by radioactive waste.

"The inspector was responding to complaints about the pigeons being a health hazard by the local community and rumours that they could be radioactive as a result of roosting at Sellafield. (Renamed from Windscale site of one of Britian's worst nuclear accidents).

www.nucleartourist.com/events/windscal.htm

A BNFL spokeswoman confirmed they had tested around 150 of the dead birds and found significant levels of radiation." (Decades after the accident was supposed to be cleaned up).

http://news.bbc.co.uk/2/hi/uk_news/55612.stm

Radioactive animals are common in the huge nuclear wastelands of Hanford Washington, Savannah river South Carolina among other lesser known sites. These animals find their way off the reservation all the time. The government monitors the animals to gauge local contamination.

http://www.usatoday.com/news/nation/2011-02-02-1Aradioactive02_CV_N.htm

http://www.gpb.org/news/2011/04/11/researchers-use-wildlife-to-track-radioactive-clean-up

Anonymous said...

Robbie001 sez:

@7:40

IMO the people in the effected region will be marginalized and forgotten as soon as possible. People who exhibit symptoms of radiation exposure will be told they have radiation phobia and their illness is related to stress and not unquantified exposure. This was the case after Chernobyl "it all in your head" was accepted by the WHO and the IAEA as a valid explanation. Some phobia supporters went as far as to claim Europe experienced massive abortions due to radiation fears. But records show little if any excess abortion compared to the years before Chernobyl. Radiation phobia has been slowly losing supporters as it is discredited by time but no reason it can't be revived in Japan.

http://en.wikipedia.org/wiki/Radiophobia#Radiophobia_and_Chernobyl

2) I think it is really impossible to determine the risks of further explosions but it doesn't look good. TEPCO has been attempting various explosion mitigation protocols like nitrogen purges so it seems they are still concern with excess hydrogen/oxygen production.

A variation of the China syndrome is always possible until the nuclear fuel is brought under control but a huge white hot mass melting through to the water table probably won't happen. The magnitude would depend on the volume of fuel involved and the configuration it takes. Certain shapes can magnify neutron activity you can't just pour fissionable material into any shaped container you like. Some shapes increase activity and some diminish it. If the fuel becomes dispersed and diluted it may just horribly contaminated the immediate vicinity below the RPV. If the corium collects into a large enough mass It could breach the foundation. The lack of information on the subject is due to the fact everything is just an educated guess with too many unknown variables to give a definitive answer.

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