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July 2012 Incidents

July 2012 Incidents

 

1/8/2012 - Fukushima live camera has changed the position to give a better view of th ongoing works at unit 4

http://www.tepco.co.jp/en/nu/f1-np/camera/index-e.html

31/7/2012 - Strange Health and Safety Deficits in TEPCO Employment continue

The next case of a sick worker on July 30th,2012. TEPCO reports:

At around 1:00 PM on July 30, since a worker from cooperative company who worked for the tank assembly inside the nuclear power plant claimed that he was in bad shape during the outwork, he was transported to the Unit 5 and 6 emergency medical room and had the medical examination by a doctor. Since the worker got a diagnosis that he had to have the medical examination in a medical organization, we called an air ambulance at 2:04 PM. The worker was transported to Fukushima Daini Nuclear Power Station by the ambulance at 2:27 PM, and was transported to Iwaki Kyoritsu General Hospital by the air ambulance at 3:03 PM. For reference, no radioactive material was found on the body.

 

25/7/2012 - Strange Health and Safety Deficits in TEPCO Employment

The admin has reported several times that TEPCO sends contract workers to work in Fukushima which are too old or too sick to do the hard work. Two workers already died due to advanced age and bad health state. None of these deaths or other collapses reported is connected to radiation. Evidently TEPCO does not take its responsibility for health and safety of the contract workers serious. There are also rumors that subcontractors are connected with the Yakuza forcing the workers to work in Fukushima against their own will and robbing part of the salary from the workers without 'TEPCO taking serious actions against. Today's press release from TEPCO adds to this picture:

-At around 9:30 AM on July 29, since two workers from cooperative company who worked for the debris removal at upper part of the Unit 3 reactor building said that they were in bad shape during the outwork, they were transported to the Unit 5 and 6 emergency medical room and had the medical procedure as drip etc. Since the two workers had the disordered consciousness and could not walk by themselves, they were transported to J-village by the ambulance. At 0:08 PM on the same day, they were transported to Iwaki Kyoritsu General Hospital by the ambulance. The workers are under medical examination and treatment by doctors at the hospital. For a reference, no radioactive material was found on the body.

Admin's comment: TEPCO should be required to have indepedent experts for radiation protection and health and safety on the work site.

25/7/2012 - Decontamination Works in Tamura City

The Government has started decontamintion works in Tamura City. The plan is to decontaminate 400 houses and 420 hectares of farmland and forest within the next months. The activity is not serious but just window dressing for the press. As the religious holiday of worshipping to the dead anchestors draws near the idea is to clean up the access to shrines and graveyards in the area and to make the old people coming to visit these places feel safe. Basically nonsense, the old people do not run a risk of radiation induced cancer anymore - too old -, but the young people doing the clean-up are at risk.

The government has also reviewed the evacuation zones. In the beginning of the accident evacuation zones are simply based on distance from the plant, since no one knows were the radioactive cloud will pass and where the fall-out might occur. So evacuation of places within a certain radius is the only feasable option.

Now the evacuation zones can be rezoned according to the measured radiation. This has been done in Chernobyl and this is what the government will do in Fukushima. The greatest problem is drawing a line on the map according to the maximum allowable value . From the stand point of radiation protection a value of 9.5 is the same as 10.5, but if 10 is the limit, people living on the left side may return and on the right side of the limit not. This is hard to explain by reasonable arguments.

The map shows the planned rezoning of the evacuation zones. Tamura is just west of Fukushima Daichi.

 

25/7/2012 - Japanese Tsunami Assessment Regulation

The admin has finally obtained the link to an English version of the Japanese Tsunami Assessment Regulations:

http://committees.jsce.or.jp/ceofnp/system/files/JSCE_Tsunami_060519.pdf

The admin has always pointed out that TEPCO is not to blame for underestimating the height of the tsunami as long as TEPCO has been following the state of the art. Basically, after the 2004 Christmas tsunami TEPCO engineers calculated the tsunami height for Fukushima in case the same tsunami would have hit Fukushima: 20 m height requiring a substantially higher tsunami wall. The management calculated the costs: too expensive.

The same holds for the mobile injection in Germany: The engineers recommended, the managemanent calculated the costs, the result: insufficient equiment, inadequate training.

23/7/2012 - New interesting technical papers from TEPCO

TEPCO has published the  Documents Used in “TEPCO Fukushima Daiichi Nuclear
Power Station Accident Technical Workshop” on the Internet:

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120723_05-e.pdf

Though mostly in Japanese, many figures can be immediately understood. The papers are a MUST for every interested technical nucler expert.

 

21/7/2012 - Dosimeters manipulated?

Asahi Shibum reports that workers from subcontractors have manipulated their dosimeters by putting a lead foils over the counter. In this way they were able to extend their paid working periods on the site.

Admin's comment: Basically, a worker has more than one dosimeter, the counter and in addition a glass badge and/or a film dosimeter. This point is not addressed in the article. The worker receives the dosimeters when entering the controlled area and gives them back to radiation control when leaving the control area. The values are entered into a control book kept by TEPCO radiation control and not by the subcontractor.

On the other hand, lead foils of the correct thickness must be provided by a radiation expert, otherwise the measured values are unreasonable and immediately detected. You do not go into a highly contaminated environment and come back with nothing on your dosimeter. Lead is a very good radiation protection material and even thin foils cause a substantial reduction, not only 10 or 20 % but 90%. No chance that such a manipulation will not be detected by the radiation protection people.

 

20/7/2012 - Fresh Fuel element removed from unit 4 SPF

Unit 4 SPF contains 1331 used (highly radioactive) fuel elements and about 200 fresh fuel elements. Fresh fuel elements have a very low radiation level and can be handled without radiation protection. Though the unit 4 protective housing over the SPF has not yet been installed, TEPCO has removed one fresh fuel element from unit 4 SPF and has posted pictures and movies on this open air removal.
It can be seen that TEPCO workers wash the fuel element with a high pressure spray washer and wipe it with paper towels while the radiation is measured. This procedure indicates that radiation level is low. This can be so for two resons:

1) TEPCO is doing an effective job by continuously decontamination the closed circuit cooling water of unit 4 SPF and is keeping the radiation level of the SPF water low.

2) There is only little fuel rod damage in unit 4 SPF, but a contamination level requiring so little decontamination effort is a surprise.

The dark square rod is the fuel element as can be seen from the typical bottom end, one worker is wiping, the other holding the spray cleaner and the third is holding the lance with the radiation monitor, the fourths is maneuvering the element, while four other workers are in stand-by watching the four at work.

Admin's comment: Common sense dictates to wait with this kind of removal work until a cover has been installed allowing a controlled atmosphere. This kind of premature action can easily lead to unwanted radioactive release. It reminds the admin of an episode in the 60 ths ( or 70ths) of the last century when the German nuclear ship "Otto Hahn" changed fuel elements in the port of Hamburg just on the quai - without any preventive measures.

19/7/2012 - The admin has compiled a list of abbreviations used in the report for Japanese Systems, e.g. D/W etc. The list is here. 

19/7/2012 - TEPCO has published material on the contamination on sea food caught offshore the Fukusima prefecture. The results look reasonable: sea food which is attached to the ground is signifantly contaminated, some of it above the limits. Other sea food, particularly fish moving around in the ocean shows low values.

5/7/2012 - The japanese Governement (DIET) has prepared its own report on the Fukushima accident, which has been published today. The english version of the summary is to be found  here: http://naiic.go.jp/en/ The main report is coming soon.

It is quite interesting to note that the international press already makes definite statements on the content though they did not have the chance to analyze the report. All they can have done is to skip through the summary. Without reading the report, the reader can be sure that the report will put the blame on the operators - such reports always do this.

 

3/7/2012 - Report on Mobile Injection with English Translation

The admin has prepared a separate document from the TEPCO final accident report concerning the mobile injection and has added some rough english translation and some helpful comments, making it easier to be read. Click here to read this document.

3/7/2012 - Sea food caught in the sea off Fukushima prefecture showing low radiation levels

Some types of fish have been caught and analyzed for radioactivity. The fish has low radiation levels and has been sold in shops and restaurant at a lower price than the usual one. In view of the new japanese radiation limits for food - much lower than those valid in the EC - there is no reason to object.

3/7/2012 - Hot particles in Tokio?

In a park in Tokio nine spots of high ground radiation levels have been detected and decontaminated. The highest value measure was 1.22 mikro Sv/h. Since the Fukushima accident 150 "hot spots" have been detected in the urban area of Tokio inspite of general opinion that no substantial fall-out from the accident has occurrred here.

Admin's comment: This is really bothering me. A former collegue of mine used to hypothesise on "hot particles", which are particles that have accumulated large numbers of radioactive atoms which are usually expected to be in form of gas. In form of gas these atoms do not constitute a potential thread to human health but a person incorporating such a hot particle will experience substantial radiation levels and health damage - and no one will connect this to radiation. The Tokio hot spots might point in this direction and a careful examination of the radiation source would be helpful but also rise public concern. So the government thinks to better leave it alone.

3/7/2012 - Inspection of unit 1 torus

TEPCO reports on the inspection of unit 1 torus on June 26, 2012:

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120627_02-e.pdf

The admin does not share the TEPCO analysis:

1) A substantial amount of radioactivity seems to be swimming on top of the pool which is indicated by the temperature jump from 37,2°C at the water level to 34.0°C just below in connection with a jump in the radiation level from about 4000 mSv/h above and below the water level to 10.300 mSv/h at the water level. Maybe the radioactive material is caught in the surface layer by surface tension. The rest of the pool looks well mixed by convection of heat generated at the bottom.

2) Close to the bottom extremely high radiation levels have been read from the instruments. TEPCO has concluded that the instruments have failed. This may be so and the instruments may show wrong readings but this is an indication of exceedingly high radiation levels close to the bottom resulting from highly radiaoctive material that has leaked from the RPV and has accumulated in form of debris at the bottom of the torus.