Tag Archives: contamination

Day 68: Video of work at Fukushima and a encouraging PDF

TEPCO has released a video that shows work being done at the Fukushima plant. Very interesting to watch.

One gets a real sense for the devastation the tsunami inflicted while watching that clip.

TEPCO also recently released this PDF file that gives an overview of work being done. I will add some pictures from it:

In the above picture one can see how they plan to rig up the new heat exchangers for reactor 1. Within the reactor building, but outside the containment, they will put a water to water heat exchanger. They will pump water from within the containment through this heat exchanger, where it transfers the heat to a secondary circuit that in turn flows to a heat exchanger outside of the reactor building that dumps the heat to the air. This is the original plan TEPCO had before they realized the full extend of the damage to the number 1 core and containment, so it is not sure they will progress as described. But the secondary heat exchanger and its piping is already being built.

Tepco also shows the above picture on how they plan to reuse leaking water from the containment as cooling for the reactor. It is not clear how the two plans are connected to each other. I would assume the second plan is the one that is going to be used instead of the first plan. Instead of taking water directly out of the containment they will use the existing leakage paths, purify the water and pump it back into the reactor.

For the number 2 reactor shown above the main problem is to stop the leakage from the suppression pool. They plan to excavate the reactor building in order to access the room where the suppression pool is housed and then fill the entire volume with grout. Considering that (probably) the suppression pool is leaking at number one as well then maby this plan will be implemented there as well (just my speculation).

Both in unit 2 and 3 are they planning to reuse the leaking water in the same manner as in unit 1.

In the rest of the document they give some basic information on how they plan to clean the massive amounts of contaminated water that exists on the site, some details on the protective building they want to build around the reactors and how to prevent more contamination of soil, water etc. Well worth scrolling through, massive work is certainly ongoing at the site and it seems TEPCO has a solid plan that they are implementing.  Of course more surprises will without a doubt pop up during work, but it looks promising. We are still waiting for more in depth information on the situation of the number 2 and 3 reactors.

English blogs:
All Things Nuclear TEPCO Says Core of Unit 1 Melted
Atomic Power Review Fukushima Daiichi update, Weds. morning 5/18

English News:
New York Times Venting Failure in the Nuclear Reactors at Fukushima Daiichi
Reuters UK nuclear power gets green light

/Johan

 

Day fifteen after the tsunami

Update 15:00(UTC)/16:00(CET)/00:00(JST)

NISA has released their update, link 1, link 2, link 3. I have also reattached the earlier JAIF figures at the bottom of the last update to see if it will fix the bug that gives an error when one clicks on the pictures.

As usual the NISA figures are between (). The NISA data is 3 hours older than the JAIF data.

 

Reactor 1:
Water level in the core: 1.65(1.65)  meters below the top of fuel assemblies
Flow rate of injected water: 7.2 cubic meters per hour
Core pressure: 476 (477) kPa
Containment pressure: 270 (270) kPa *note, in the last update I misstakenly wrote 370 kPa as containment pressure.
Core temperature(feedwater nozzle): 195.3 Celsius
Core temperature(bottom head) 146.3 Celsius
Dose rate within containment: 35.1 Sv/hour

Reactor 2:
Water level in the core: 1.1 (1.1)  meters below the top of fuel assemblies
Flow rate of injected water: 18.6 cubic meters per hour
Core pressure: unknown
Containment pressure: 116 (115) kPa
Core temperature(feedwater nozzle): 107 Celcius
Core temperature(bottom head): 100 Celsius
Dose rate within containment:  43.4 Sv/hour
Spent fuel pool temperature:  57 Celsius

Reactor 3:
Water level in the core: 2.3  meters below the top of fuel assemblies
Flow rate of injected water: 14.5 cubic meters per hour
Core pressure: 139 (139) kPa *note, I wrote the wrong pressure in the last update
Containment pressure: 106.6 (106.6) kPa
Core temperature(feedwater nozzle): 37.6 Celsius (sounds like an error on equipment)
Core temperature(bottom head): 106.1 Celsius
Dose rate within containment:  36.1 Sv/hour

Due to my error with containment pressure in the last update I withdraw my speculation that its hard to control the pressure in number 1. Rather it seems like the situation is fairly stable. Otherwise not much new information.

The US Department of Energy has done some arial surveys around Fukushima Daiichi and released the data. I have one pictures from it below(hats of to http://neutroneconomy.blogspot.com/ where I found the pictures). The dose rate unit used on the picture is millirad. 1 millirad=10 microgray =* 10 microsievert
*that equality between gray and sievert is only valid for gamma radiation. Gray measures the energy deposited while sievert is weighted in such a way that it expresses a cancer risk.  For gamma the weighting factor is 1.

Update 12:00(UTC)/13:00(CET)/21:00(JST)

No NISA updates have been released yet today, JAIF has released their update as usual(one hour old as of writing this).

Reactor 1:
Water level in the core: 1.65  meters below the top of fuel assemblies
Core pressure: 476 kPa
Containment pressure: 370 kPa
Core temperature(feedwater nozzle): no new data
Core temperature(bottom head) no new data
Dose rate within containment:  no new data

Reactor 2:
Water level in the core: 1.1  meters below the top of fuel assemblies
Core pressure: unknown
Containment pressure: 116 kPa
Core temperature(feedwater nozzle): no new data
Core temperature(bottom head) no new data
Dose rate within containment:  no new data

Reactor 3:
Water level in the core: 2.3  meters below the top of fuel assemblies
Core pressure: 202 kPa
Containment pressure: 106.6 kPa
Core temperature(feedwater nozzle): no new data
Core temperature(bottom head) no new data
Dose rate within containment:  no new data

All 3 reactors are now cooled with freshwater instead of sea water. It seems hard for them to get the pressure in the number one reactor under complete control. In JAIF's written update they say lights are on in all control rooms now. Levels of radioactive materials in the seawater around the plant is climbing. TEPCO is releasing updates on activity in both sea and air, I have attached levels as pictures in the bottom of this update.

The ground deposits of I-131 the prefectures around Fukushima ranges from less than 1 to 16 kBq per square meter. The cesium ground deposits ranges from less than 0.1 to 1.9 kBq per square meter(here are the last 3 MEXT updates on ground deposts link 1link 2link 3). The data form the worst effected prefectures are however omitted, we hope MEXT will make those figures available asap! As a comparison the ground deposits of cesium due to Chernobyl ranged from a couple of hundreds to a couple of thousand kBq per square meter.

 

Update, March 26, 12:00 (UTC) / 13:00 (CET) / 21:00 (JST)

Not much to add today. The radiation levels in the sea outside Fukushima I are sky-high. The long term effects are hard to predict now since a sea contamination is entirly different from a land contamination, where land is basicly a 2D area, which leads to a thin and high concentration on the surface, and where rains soon concentrate the contamination to "hotspots".  The sea on the other hand is a 3D volume where currents quickly dilute any contaminant by dispersing them over very wide areas.

The JAIF updates from 10:00, 16:00 and 21:00 (JST) for March 26 are pretty much uniform. The big news is that freshwater injection to the cores of 1, 2 and 3 has started as opposed to using salty sea water. Apart from that nothing new. The radiation readings at the main gate (1 km out) has stayed at 170 μSv/h all day. The west gate read 147 μSv/h at 13:30.

NISA has not said anything new since last night.

 

Links(english):
BBC We should stop running away from radiation
Hufftington post US brings fresh water to japan nuclear plant
NY Times Japan presses nuclear plant repair as more damage is found
Rod Adams Shaken, flooded, stressed by power outages, Fukushima Daiichi moves into second place
The Independent Fear and devastation on the road to Japan's nuclear disaster zone

Links(swedish):
Röda berget
Dr Angels blog
DN Radioaktivt jod tusen gånger tillåten nivå i havet
Aftonbladet Strålningen ökar runt Fukushima
SvD Radioaktivt vatten i reaktorer
Tänkvärt? Eller inte!
Grön horizont

 

Day fourteen after the tsunami

Uppdate 22:45(UTC) / 23:450(CET) / 07:45(JST)

There has been no further info yet on the status of the exposed workers or the status of the reactors. Only news about the reactors is that both number 1 and number 3 have now switched to fresh water injection into the core and number 2 was supposed to follow promptly. I end todays updates with a few video clips of the explosion in one of the refineries that was hit worst by the earthquake and tsunami. This disaster has struck so many lifes, so many industries and so many towns that it is hard to fathom.

 

Uppdate 16:30(UTC) / 17:30(CET) / 00:30(JST)

The 2 workes taken to hospital reportedly got a dose to their feet and lower legs between 2-6 Sieverts from beta radiation.  They also got close to 200 mSv from gamma and an unknown internal dose.

They have not shown any signs of acute radiation sickness so far.  But the dose to the legs are very worrying and in the worst case might mean amputation.

Update 14:15 (UTC) / 13:15 (CET) / 22:15 (JST)

New updates from JAIF and NISA(link 1, link 2, link3). JAIF status is from 15:00 JST and NISA updates from 10:00 and 12:30 JST. As before the first number is from the JAIF update and the number within () is from the older NISA update.

Reactor 1:
Water level in the core: 1.65 (1.65) meters below the top of fuel assemblies
Core pressure: 450 kPa (450 kPa)
Containment pressure: 295 (295) kPa
Core temperature(feedwater nozzle): 197.8 Celsius
Core temperature(bottom head) 153.6 Celsius
Dose rate within containment:  38.9 Sievert/hour

If one looks at the JAIF status updates one can see a very encouraging piece of information, they have switched from seawater to fresh water injection into the pressure vessel! That is one significant step in the direction of stabilizing the reactor since seawater injection could never be a permanent solution. They are still not using the internal pumps however. The temperature of the core seems to have been brought under control and the high containment pressure is on a slowly declining trend. We can only keep our hopes up that they will be able to avoid venting the containment.

Reactor 2:

Water level in the core: 1.20 (1.2) meters below the top of fuel assemblies
Core pressure:  unknown
Containment pressure: 120 (120) kPa
Core temperature(feedwater nozzle): 107 Celsius
Core temperature(bottom head) 105 Celsius
Dose rate within containment:  45.6 Sievert/hour

Reactor 3.
Water level in the core: 2.3 m below the top of fuel assemblies.
Core pressure: 139 (139) kPa
Containment pressure:  107 kPa
Core temperature(feedwater nozzle): 42.8 Celsius (probably junk)
Core temperature(bottom head) 111,6 Celsius
Dose rate within containment:  51 Sievert/hour

Preparations are being made to switch from seawater to fresh water for reactor 2 and 3. If it goes as quickly as for number one it should be done within half a day. Work with electrical equipment on going.

We have earlier warned for the possibility that molten material in the core can be lying on the bottom of the vessel and eating its way through, now that seems unlikely considering how low the bottom head temperatures of the vessel are. All of them are below 200 degrees.

Dose rate at main gate around 200 micro sievert per hour.

Update 12:30 (UTC) / 11:30 (CET) / 20:30 (JST)

TEPCO is preparing to switch from salt water to fresh water for the core cooling. From NHK:


TEPCO says it intends to switch over from pumping sea water to pumping fresh water into the 3 reactors, as salt in the sea water could cause corrosion and buildup, hampering the smooth flow of water inside the structures.

The company has been pumping seawater as an emergency measure.

The power company also says preparations to switch to fresh water were completed at the No.1 reactor on Friday afternoon.
Operations to pump fresh water into reactors No.2 and No 3 are expected to start later in the day.

Update 10:00 (UTC) / 11:00 (CET) / 19:00 (JST)

Here are the status tables from the JAIF update described below and summary.

Reactor 1:
Water level in the core: 1.7 meters below the top of fuel assemblies
Core pressure: 465 kPa
Containment pressure: 310 kPa
Core temperature(feedwater nozzle): no new info yet today
Dose rate within containment:  no new info yet today

Pressure has decreased by about 60-80 kPa in both vessel and containment since yesterday.

Reactor 2:
Water level in the core: 1.10 meters below the top of fuel assemblies
Core pressure: unknown
Containment pressure: 120 kPa
Core temperature (feedwater nozzle): no new info yet today
Dose rate within containment: no new info yet today

Reactor 3.
Water level in the core: 2.3 m below the top of fuel assemblies.
Core pressure: 139 kPa
Containment pressure:  107 kPa
Core temperature (bottom head): no new info yet today
Dose rate within containment: no new info yet today

Containment damage is again suspected on number 3, otherwise no major changes since yesterday. Let's hope the containment is not damaged! Luckily the reactors in the possibly damaged containments are behaving more stable than the number one reactor (that has a undamaged containment).

Picture of reactor number 3 building

Update 08:45 (UTC) / 09:45 (CET) / 17:45 (JST)

The 16:00 JAIF update for March 25 has been published. Two changes:

...so far seventeen workers have been exposed to more than 100 mSv of radiation.

100 mSv is the limit where an increase in cancer risk has been proven. At 100 mSv, the lifetime risk of getting cancer increases from about 25-32% to 29-36%.

Keep in mind that this does not say whether or not any of these workers will actually get any cancer, much less die from it. It is safe to assume that just as after Hirosima/Nagasaki, the medical authorities will keep those exposed under very close watch, meaning their chances of getting diagnosed early and thus surviving any cancer will be quite good.

The other change is that the radiation reading at the main gate has gone up again:

The Main Gate: 259.0μSv/h at 11:00, Mar. 25

The pressure in the #1 containment vessel is moving up and down.  #2 is stable. The #3 pressure is slowly decreasing. With the worries of a leak from #3, this may have more than one explanation, not all of them good.

Update 07:20 (UTC) / 08:20 (CET) / 16:20 (JST)

The 10:00 (JST) JAIF update for March 25 has the following new entries:

Monitoring results of seawater sampled at the coast near the Fukushima Dai-ichi NPS on Mar. 23rd showed that radioactive Iodine, Cesium, Ruthenium, and Tellurium exceeding the regulatory limit were detected. Also, monitoring results of seawater sampled at coasts within about 16km from the Fukushima Dai-ichi NPS in Mar. 23rd showed that radioactive Iodine and Ruthenium exceeding the regulatory limit were detected.

Nuclear Safety Commission of Japan reported the result of preliminary calculation of exposure dose in the surrounding area of Fukushima Dai-ichi NPS.

The dose rate mesaured at the main gate has dropped slightly, from 209.4μSv/h at 12:00, Mar. 24 to 193.8μSv/h at 06:00, Mar. 25.

The high exposure of three workers in the number three turbine hall suggests that #3 may have a leak after all, says the government's Nuclear and Industrial Safety Agency.

Water supplies continue to show taints of Iodine-131, but the readings fluctuate and it's still hard to make out a general trend. Tokyo is no longer under a recommendation not to drink the tap water, but concerned citizens continue to use bottled water to some extent.

Following the latest findings, the Tokyo officials said it will no longer warn against consumption of tap water in the metropolitan area.

''I believe readings will go up and down. But even if levels exceed standards temporarily, it will be no problem as long as they stay (most of the time) within the range throughout the year,'' Tokyo Gov. Shintaro Ishihara said at a news conference. ''I hope people in Tokyo would act calmly.''

Still, people in the capital area -- located about 220 kilometers from the crippled Fukushima Daiichi nuclear plant -- and elsewhere continued to buy up limited supplies of bottled water from shops and vending machines.

The government has asked that people in the 20-30 km zone around the crippled Fukushima plant to evacuate volontarily out of concern for supplies for daily necessities.

The Japanese government has encouraged people living within 20 to 30 kilometers of the troubled nuclear plant in Fukushima Prefecture to leave voluntarily, with concerns over access to daily necessities rather than resident safety prompting the advice, top government spokesman Yukio Edano said Friday.

 

 

Länkar:

SvD mycket troligt en läcka i 3an
Flute
Kommunisternas blogg
Martin Mobergs blogg
Röda berget
Aktieskolan
Cornucopia
Röda malmö
Divage

DN Kärnan kan vara skadad (den person som valde den här rubriken borde sluta använda google translate....)
DN cesium i grönsaker i Tokyo
Aftonbladet hotet i japan är osynligt

Chris Busby and "The Tall Tale Of Ten Tons Uranium Gone Missing"

Professor Chris Busby is a man that has made himself somewhat of a career in being the golden boy of nuclear opponents, saying just the things they want/need to hear. There is only one problem with this: he doesn't have a foot to stand on when it comes to his tall tales about the evils of nuclear power. Previously we have exposed his claims that the Chernobyl disaster supposedly caused an increase in breast cancer in Sweden. This turned out to be an unfounded conclusion, based on frivolous interpretation of data along with some outright cherry-picking and willful suppression of data that didn't fit the claim.

In the case of The Tall Tale Of Ten Tons Uranium Gone Missing, Busby and his colleague Cecily Collingridge have issued a report where they claim that there has been a leak of enriched uranium from the British nuclear power plants at Hinkley Point in the order of about 10 000 kg. We analyzed the data which he used to make his claim, and took the same steps as he did, following his chain of reasoning from data to conclusion. The result is hardly flattering for the Busby and Collingridge, because the claims they make hinge on...

- Unsupported postulates

- Sparse and highly uncertain data

- Graph fitting done on this data, while ingoring uncertainties

- Low resolution geological surveys

- Misreading of said surveys

- Ignoring local variations in said surveys

- Ignoring missing indicators that must be present if their claim was true

All over the place...
When you can fit any random graph of the data, in this case an elipsoid, something is not right.

The full analysis can be found in our forum. But I'll just cut right to the chase and ask the obvious question: how would 10 tonnes(!) of uranium go missing without anyone noticing? And more important: why didn't anything else go missing? The data that Busby uses to make his claim shows barely detectable levels of fission products, such as Cobalt-60 or Cesium-137. Considering that uranium is a lot less mobile than these products, if uranium goes missing but not the fission products, there cannot be a leak in the reactors because any such leak would have seen more fission products escape than uranium.

This leaves only one path as to how 10 tonnes of uranium could escape into the environment: when reactor fuel arrived fresh at the plants, someone took some fuel elements aside, stripped them of their cladding, ground them to dust and blew them out over the surrounding areas. Alternatively someone made a bonfire with them. And all of it happened without anyone noticing.

Since this is clearly not a reasonable explanation, we must conclude that Busby and Collingridge are wrong: there has not been a leak of 10 tonnes of uranium from Hinkley Point. The data they rely on does not support the claim, and it is only through their frivolous interpretation of the data, misreading some of it, and making unsupported assumptions that they arrive at the claim.

This begs a final question: claims have been made that there are numerous health problems around Hinkley Point, such as an increased incidence of childhood leukaemia. If there are no leaks from Hinkley Point, how would this be explained? Well... to find that answer, maybe you should go ask the one person making the claims: a certain professor Chris Busby.

/Michael Karnerfors and Mattias Lantz - members of Nuclear Power Yes Please