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Reentry into unit two and other matters in Japan

Because of the high humidity inside the unit two building an attempt by a robot to enter the building did not work. The humidity (water vapour) clouded the robots vision and prevented it from going inside.

A team of four workers entered the building to check the radiation levels and other things inside. The team found that the radiation levels were between 10 and 50 mSv per hour. These dose rates are too low to cause “instant death”. To reach a 2 Gy dose of gamma rays a person would have to stay in the 50 mSv per hour part of the buildings for 40 hours, even at 2 Gy death would be unlikely as a misguided person who sat in the 50 mSv h-1 spot for almost two days would have access to good medical care when they finally emerge from the building.

TEPCO are trying to improve the cooling of the used fuel pond to reduce the humidity in the building and thus improve the conditions for workers who have to toil inside the building. It is important to understand that in a damaged nuclear plant not only is the radiation a threat to the wellbeing of the work force. During the Three Mile Islandcleanup some workers over heated inside their anticontamination suits. I imagine that being inside an anticontamination suit in a hot place would be like being the kipper in a boil in the bag kipper. (Neither healthy nor nice!)

As part of the transition from a dire accident to a controlled careful cleanup a pair of special fork lift trucks with ten centimetres of steel plate as shielding, a 20 cm lead glass window and air filters to protect the operator will be delivered to the site. According to Yasufumi Ohsaki (Mitsubishi Heavy Industries) these machines will be used to clear rubble and thus hasten the normalisation of the situation at the reactor site. I think that clearing rubble from around the site is an important activity which will allow workers to deal more effectively with the reactors.

Another step in the right direction is the establishment of a special office of the Japanese health ministry. This office will watch over the radiological health of the workers who are toiling on the site.

TEPCO have explained how they are planning by June to start to reuse cooling water. The idea is that cooling water will be injected into the plant; the used water will be cleaned up using a zeolite column. I think that the idea is a reasonable idea which will help with the clean up.

I suspect that the use of a zeolite to clean the water will minimize the volume of radioactive waste water which needs to be processed off site. Also the zeolite will absorb much of the radioactivity. It will concentrate the radioactivity into a small volume which will be cheaper and safer to dispose of.

At the same time the fishing and farming cooperatives have started to bring civil claims against TEPCO. As I am not a combination of the judge and jury I will not try to usurp the court and say how much the compensation should be. I am sure that this accident will result in a series of court cases, but I have no idea of how they will turn out.

Already the farming community has been subject to special rules and now the government have banned the growing of rice in the 30 kilometre zone and in some areas where the radioactive cesium level is high. While farmers may not like being told that they can not grow rice, I think that the rice ban is in the interests of society.

I would like to pose the question of “what should TEPCO / MEXT do about the accident ?”

I hold the view that rather than paying farmers and fishermen to do nothing, that TEPCO / MEXT should strongly consider the creation of worthwhile alternative economic activities which will prevent unemployment within the fishing and farming communities. One problem which TEPCO have right now is that they are running low on money. TEPCO are selling off assets, the workers are being subjected to pay cuts and the executives are going to have no pay.

What ever people might think about the way which TEPCO have behaved I think it is important not to blame the rank and file members of the workforce. I suspect that the typical plant worker is a person who is trying hard to make the best of a very bad deal. The people who have been toiling at theFukushimasite should not get a pay cut, if anything they should be given a special bonus for their good work.

I think that either TEPCO needs to be kept afloat or some other body needs to take over the financial obligations of TEPCO. One option would be for other energy companies and utility companies could provide assistance to TEPCO to try to keep the company afloat so that it can continue to clean up the mess and compensate the victims. Another option is for the state to bail out TEPCO.

In the recent past in the UK a series of banks have collapsed or at least come close to collapse. The UK state bailed out the failing banks, I agree with the idea of the bail out but I hold the view that the bail out should come with strings. The bailed out bank should be subject (forever) to a set of rules which limit the bonuses of staff and prevent the bank doing irresponsible things which cause banking chaos.

In the same way if TEPCO is bailed out by the state then the state should get something in return, TEPCO should not be allowed to profit from this event or to get an easy ride at the expense of the tax payer. One option would be for TEPCO to issue shares which be sold to the government. So perhaps TEPCO may be nationalised by the Japanese government, the government would then become a major shareholder in TEPCO.

Now for a moment let us assume that TEPCO will stay afloat, now we need to consider what it should do.

One scenario would be for TEPCO to provide training to a team of farmers who would then be paid to perform dose reduction actions on farmland. I suspect that the farmers may already have some of the equipment needed for the work. For example deep ploughing and potassium fertilizers are method for reducing the transfer of cesium from grass to cows.

The Japanese have been reported to be considering flooding rice paddies with water, stirring them up and trying to flush away the radioactivity. I fear that this will not remove cesium from the soil. The stirring up might have the same effect as deeply ploughing a European field as if all the soil becomes a slurry then if the soil has come clay in it then the cesium will stick to the clay.

Another idea is to use zeolite in drainage channels to extract the cesium inside a small volume of the mineral. This will make the waste processing more easy, if the government was to scrap 1 cm of the soil then a vast amount of contaminated soil would need to be disposed of as radioactive waste. I think that top soil removal should be reserved as a last resort method for dealing with stubborn radioactive stains on the land. A less dramatic method is to use pytoremediation of the land. This is a fancy term for “cleaning with green plants”.

A fast growing plant like rape or sunflowers can be used to clean the soil. To work well the plant needs to be easy to grow, fast growing and able to extract cesium from soil. Vast fields of sunflowers could absorb cesium from the soil. As long as the Japanese society has devised a disposal method for the fully grown sunflowers then this crop could be of some use to the farmers. I reason that a typical Japanese farmer will be unhappy about now being able to earn a living the way he used to.

Even if a farmer was given the same amount of money as he earned in a year from farming and was told to sit on his bottom then I think that many farmers would be unhappy. I think that being able to farm an alternative crop or to farm in an alternative way of farming would be good for the mental and social wellbeing of the farming community.

One idea which I have seen before is for the farmers to change from growing food crops to growing plants which can be harvested for oil. The oil from sunflowers or rape could be used in industry or for making fuel oil. According to one book which I have read on the topic, the part of the plant where the oil is harvested from has very little radioactivity while the other parts of the plant contain plenty of radioactivity.

Maybe a contaminated farm could be changed from a food farm into a vegetable oil farm; if the oil is not suitable for food use then it could be converted into biodiesel. The biodiesel could be used for cars, trucks and buses as a replacement for normal diesel. The more radioactive parts of the plants could then be disposed on in a special way to avoid returning the radioactivity to the top soil.

If you are interested in the way that vegetable oil is converted into diesel then I can tell you something about it. Normal vegetable oil has the wrong mechanical and physical properties for use in a diesel engine. Also it is very hard to use sunflower oil in an oil lamp; instead the very large molecules in the vegetable oil need to be shortened to make them suitable for use.

One classic method is to make the FAME type of diesel fuel; this is the Fatty Acid Methyl Ester type of diesel. In common with diesel fuel production the formation of the methyl esters is often done in chemical labs when we want to analyse cooking oil. For analytical purposes my normal method is to shake a hexane solution of the cooking oil with potassium hydroxide in methanol. Then after allowing it to stand for a moment, I remove the glycerol rich bottom layer with a pipette and then I wash the mixture with brine, remove the brine, dry the hexane layer with sodium sulphate. Then I dilute it and inject it into my divining stick (opps I mean GC machine)

For making biodiesel the easy way is to boil methanol with cooking oil with some sodium hydroxide added. After boiling it for an hour, I let it cool. I then remove the bottom layer, then I wash the upper layer with dilute acetic acid, then with water and then I tend to dry it with sodium sulphate. This reaction works in the following way, methoxide acts as a nucelophile on the glycerol trimester to form a methyl ester. This is a classic bit of organic chemistry.

The alternative method uses more modern chemistry, a fancy catalyst is used to hydrogenate the oil and also do a hydrodeoxygenation reaction, this forms a mixture of propane and long chain alkanes (parafins).

http://www.biodieselmagazine.com/articles/1505/heeding-hydrogenation/

Rather than the farmers having to work out their recovery plan on their own, I think that TEPCO and/or the Japanese government should provide guidance to the farmers, and financial and material assistance to help them change the way they earn a living from the land.

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