Sellafield is having a big clean up. It is called Britain's most dangerous building. It has 10,000 m3 of radioactive sludge. The sludge is being put into big backed bean tins and covered in Polyfilla. A robotic arm is being used to handle the sludge. But a comforting thought perhaps is that Hanford in the U.S.A. has 20 times the amount of high level nuclear waste as Sellafield. (or perhaps not so comforting after all).
Source: Not the Daily Mail.
Z.
The nuclear submarine article is an interesting read and notes the same problem as for early land based nuclear power plants, the military requirements were key, no one thought about longer term disposal.
What is not mentioned is the time element. As Mike says highly active materials decay faster than less active ones. The reactor structures of land based reactors can be left for 10s of years to decay enough to make dismantling easier. There is a benefit in waiting before dismantling, but as the article says for submarines there is also a significant maintenance cost.
The real risks from ionising radiation are also not discussed. It is fairly well established from the atomic bombs dropped on Japan and from various accidents that a rapidly received dose of 100 mSv or more will increase the risk of cancer, a dose of 4 Sv will be fatal without medical intervention and a dose of 10 Sv will be fatal. When the dose is less than 100 mSv or is delivered over an extended time the science becomes much more woolly.
The current legislative requirements are based on collective dose and the Linear Non Threshold (LNT) principle. These state that there is an increased cancer risk for any dose and that if 100 people receive 1 mSv this carries the same risk as one person receiving 100 mSv. It also follows from them that the risk of 2 mSv per year for 50 years is the same as the risk of a one off 100 mSv dose. There is no scientific basis for this and it is not supported by the large differences in background radiation levels around the world.
The average background dose in the UK is 2.5 mSv per year. Parts of Cornwall and around Aberdeen can be three times this. Do we see three times the incidence of cancer in Cornwall? Other areas of the world have more than 10 times the average background radiation level. This does not show as an increase in cancers.
https://radwatch.berkeley.edu/background-radiation/
So what are the real risks? There have been a lot of extrapolations based on mathematical models and a lot of emotional outbursts without much fact, a bit like AGW 
If I take a piece of granite into a nuclear power plant it becomes radioactive waste and has to be disposed of accordingly. Are the current rules sensible?
This HPA document goes into some detail of what is real and what is conjecture.
Ionising radiation: risks from exposure - GOV.UK (www.gov.uk)
The nuclear submarine article is an interesting read and notes the same problem as for early land based nuclear power plants, the military requirements were key, no one thought about longer term disposal.
What is not mentioned is the time element. As Mike says highly active materials decay faster than less active ones. The reactor structures of land based reactors can be left for 10s of years to decay enough to make dismantling easier. There is a benefit in waiting before dismantling, but as the article says for submarines there is also a significant maintenance cost.
The real risks from ionising radiation are also not discussed. It is fairly well established from the atomic bombs dropped on Japan and from various accidents that a rapidly received dose of 100 mSv or more will increase the risk of cancer, a dose of 4 Sv will be fatal without medical intervention and a dose of 10 Sv will be fatal. When the dose is less than 100 mSv or is delivered over an extended time the science becomes much more woolly.
The current legislative requirements are based on collective dose and the Linear Non Threshold (LNT) principle. These state that there is an increased cancer risk for any dose and that if 100 people receive 1 mSv this carries the same risk as one person receiving 100 mSv. It also follows from them that the risk of 2 mSv per year for 50 years is the same as the risk of a one off 100 mSv dose. There is no scientific basis for this and it is not supported by the large differences in background radiation levels around the world.
The average background dose in the UK is 2.5 mSv per year. Parts of Cornwall and around Aberdeen can be three times this. Do we see three times the incidence of cancer in Cornwall? Other areas of the world have more than 10 times the average background radiation level. This does not show as an increase in cancers.
https://radwatch.berkeley.edu/background-radiation/
So what are the real risks? There have been a lot of extrapolations based on mathematical models and a lot of emotional outbursts without much fact, a bit like AGW
If I take a piece of granite into a nuclear power plant it becomes radioactive waste and has to be disposed of accordingly. Are the current rules sensible?
This HPA document goes into some detail of what is real and what is conjecture.
Ionising radiation: risks from exposure - GOV.UK (www.gov.uk)
