Wednesday, March 23, 2011

Drilling down into Fukushima's facts

The following word button "Radioactive Cloud over World Nuclear Renaissance" takes you to a complete quote of this excellent synopsis of where we are now, what we have come through, and possibly where we are going or could go in the future with the nuclear crisis in Fukushima. However, in this present article I am trying to focus on the problems outlined in the quote contained in this article but which is only a small part of it.

Radioactive Cloud over World Nuclear Renaissance
begin quote:
This scenario of controlling the reactors with failing equipment could continue for months. Bringing the reactors to a safe state is not possible unless the reactors are decommissioned. That the first 4 reactors can never be used is obvious. Once sea water is put in the reactor core, it is the end of the reactor. The 4th unit has had a hydrogen explosion and is also out. It is doubtful that unit 5 and 6 will ever produce power again. They may at most be easier to maintain in a shut down state and also easier to decommission.
At any point the temperature can rise, the containment could fail and further explosions could take place. An emergency state would continue till the reactors are effectively de-commissioned People are not talking about this, but decommissioning of these reactors will not be easy, particularly as they have stored fuel in cooling ponds in the same buildings that house the rectors. It is this inventory of stored fuel rods which is likely to be the major problem. A Chernobyl solution of burying the reactors under tons of concrete for reactors could work, but not for the stored fuel rods, particularly as they are not ground level. One cannot pour tons of concrete on the 4th floor of a building – this will bring everything crashing down.
The Japanese authorities have now reported dangerous radiation levels in a 30 Km radius of the plant and also high levels of radiation in a number of food items in the Fukushima Prefecture. Much higher levels of radiation have also been recorded in sea water around Fukushima. Obviously, dangerous amounts of radiation have been released and continue to be released from the plant, even though we have no measurement of the amounts released. Even today, the operators were not able to enter one of the plant buildings because of a high level of radiation there – the level noted was 500 millieverts per hour. The normal amount of radiation a worker is allowed in Japan is 100 millisieverts per year, though this has been raised to 250 millisieverts as an emergency measure for Fukushima.
Based on the impact of the accident, the severity level of Fukushima has been revised from 4 to 5, on par with Three Mile Island but below Chernobyl. French authorities have argued that the Fukushima accident should be considered to be at severity level of 6. There is little doubt that most experts now regard the Fukushima accident to be the most serious after Chernobyl, with no guarantee as yet of the crisis dying down.end quote.

I agree that one cannot successfully dump cement on the fourth floor of the buildings where the containment rods are stored without bringing each building numbered 1 through 6 crashing down and defeating the whole purpose.  So, to me, there is no real way to compare Chernobyl to Fukushima at all. Though the final Chernobyl explosion likely was greater than anything will be at Fukushima, it must be understood how incredibly interconnectedly complicated and difficult Fukushima is to rationally and logically and practically deal with for anyone or any group of people or any country on earth at this point.

My biggest concern would be: Can this complicated mess be dealt with in any useful way without evacuating all of Japan and sending in robots to complete all the tasks?

And secondly, can a nuclear explosion be prevented of what megatonage? at reactor number three. Because its plutonium is very unstable in this kind of situation. And also since reactor number 3 is 2 million times more toxic to life on earth than the other uranium reactors, what does that mean to all life on earth in real terms and not just to Japan?

And the last question that I have heard no useful answer to is this: If reactor number 3 becomes a self starting nuclear bomb how will all the other nuclear rods in reactors 1 through 6 behave while it explodes? Will they just add to the megatonage or will they remain fairly inert and therefore not part of that particular problem. Then if it blows will it dig a hole down into the ocean or will it open up the fault lines and sink more of Japan?

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