richard_leeds wrote:manchild wrote:What's the part of the globe opposite from Japan?
It is easy to ridicule people who have little knowledge of nuclear catastrophes. It is more difficult to predict what will happen. On top people who have tried to predict what will happen have been called scaremongers.
What is clear from Tepco's original comments is the existence of several sources of re-criticality. Re-criticality are localized nuclear chain reactions that are not supposed to happen and that happen in places not designed to have a chain reaction going. It appears that re-criticalities are happening at least at the #2, #3 and #4 reactor buildings. It is clear that the re-criticality at #3 will involve much higher concentrations of plutonium than in the other three buildings. Tepco doubt that they will ever be able to enter the #3 reactor building safely. This appear logical considering the half life of some plutonium isotopes is 20,000 years.
Re-criticalities happen at places not designed for a chain reaction but in cavities and pockets that have come into existence by accident. It is therefore impossible to cool such chain reactions in a controlled way by submerging them in water and replacing hot water with cold water. All you can do is pump water above the place where you see steam rising and hoping some of the water will hit the fuel puddle that has become critical again. You basically have to do this until all the fuel that has accumulated in significant puddles has burned out or is distributed over a wider area to stop the reaction.
As this happens you have to assume that the re-critical puddles will burn through anything that lies under them which includes concrete, steel and even rock. Nobody at this time can say how long this will go on.
Assuming the remaining puddles will remain critical for a very long time it is likely that this process will create large enough cavities under sea level that will fill with seas water to cool down the reaction. That is the good news because it will eventually shut down the reaction. The bad news is that most likely such big cavities will be connected to the seas and much of the activity will be leaked to the Pacific ocean.
It means that the re-critical fuel puddles will not penetrate significantly into the crust of the earth. Fears of volcanic activity due to the nuclear accidents appear unrealistic in my view. But the main point is that we are looking at a very nasty accident that will produce more radioactive contamination than it has done until now and that could remain uncontrolled for a long time.
http://energyfromthorium.com/pps/Fukush ... iAREVA.pps
This is a good but incomplete powerpoint presentation done by the German AREVA engineer Dr. Matthias Braun
In the meantime it transpires that nuclear power stations in Europe have different cover against the economic consequences of accidents. In Germany they are covered for €2.5bn and in France against €0.072bn. It is interesting to assess what Tepco is facing from the accident.
The financial consequences will be coming from three streams of losses.
- the compensation to people who have been evacuated
- the cost of de commissioning the reactors
- the fossil fuel needed to replace electricity now produced from gas plants
- replacing the nuclear power stations
According to
this source JCO Co., a nuclear fuel processing firm in Tokaimura, Ibaraki Prefecture, that caused a criticality accident at its facilities in the village in September 1999 had to pay a total of about 15 billion yen in compensation for damage suffered by local residents, including health hazards and financial losses by farmers whose products had been shunned by the marketplace. In the JCO accident, locals living within 350 meters of the facilities in question had to evacuate. This contrasts with a massive evacuation in the vicinity of the Fukushima nuclear power plant of 30 kms and reports of excessive levels of radiation outside a 40 km radius. Let us assume that compensation will be applicable proportionally to the size of the afflicted area. The are is 7600 times bigger which leads us to a base estimate of Yen 114,000 bn or €1,000bn.
Let us assume the de commissioning of the reactors will cost ten times on average that of a normally shut down reactor which is Yen 100bn according to the same source. So we are looking at Yen 6,000bn or €53bn.
Let us assume that Tepco will have annual cost of Yen700bn for gas for eight years while the nuclear reactors are replaced. That will amount to Yen4,900bn or 43bn.
Finally we need to erect three big modern EPR reactors to replace the electric capacity which costs €5.5 each, totally €16.5bn.
Unless I'm very mistaken Tepco looks at a potential cost bill of €1,125bn. Even in Germany only a fraction of this cost would be covered by insurance. If we assume that the compensation to the evacuated is wrong by one magnitude we still look at €225bn in damages. It is a figure that still boggles the mind.
