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.
Radio activity is unstoppable, but by arranging for most of the bits that fly off as nuclii decompose to get stuck into something that is not your DNA is the usual solution. As such putting several metres of concrete or water between it and you are the normal techniques to get from 'hot' down to 'compares with natural background'
(XKCD has a novel slant on this - and considers the wisdom or not of swimming in a reactor cooling pool as one of its readers questions )
To understand why there is no single answer, realise there are several grades of radioactive material firstly in terms of decay rate
- things that are decaying fast are more dangerous today, but do not need such long term storage. Things that decay over millennia may sound frighting, but in reality, you can go and sit on a block of it, as the number of the atoms that actually decay during the time you are there is relatively few.
Then in terms of the type of decay - alpha particles can be pretty much stopped by a bit of card, beta particles - fast moving free electrons can be stopped by thin sheet metal. Gamma rays are more like super high energy X rays, and go through most things, getting only gradually dimmer.
The gamma sources with medium term half lives are the ones that are most hazardous to us. Luckily most of the waste does not fall into this category, and some of the more sensational articles do not make clear the distinction.
That's not to say that there is not some nasty stuff at sellafield that needs to be stored properly, but compared to disposal of some of the nasty chemicals we make, it is a more tractable problem, and these days far better controlled than it was in the early days.
10,000cubic metres is equivalent to a tank 100m by 100m and 1m deep. For the whole country, not such a lot, indeed it would all fit in the car park at work for example. Mind you, I'd be a bit hacked off if they did that - I'd have to park somewhere else ;-) .
Mike.
Mike.
Radio activity is unstoppable, but by arranging for most of the bits that fly off as nuclii decompose to get stuck into something that is not your DNA is the usual solution. As such putting several metres of concrete or water between it and you are the normal techniques to get from 'hot' down to 'compares with natural background'
(XKCD has a novel slant on this - and considers the wisdom or not of swimming in a reactor cooling pool as one of its readers questions )
To understand why there is no single answer, realise there are several grades of radioactive material firstly in terms of decay rate
- things that are decaying fast are more dangerous today, but do not need such long term storage. Things that decay over millennia may sound frighting, but in reality, you can go and sit on a block of it, as the number of the atoms that actually decay during the time you are there is relatively few.
Then in terms of the type of decay - alpha particles can be pretty much stopped by a bit of card, beta particles - fast moving free electrons can be stopped by thin sheet metal. Gamma rays are more like super high energy X rays, and go through most things, getting only gradually dimmer.
The gamma sources with medium term half lives are the ones that are most hazardous to us. Luckily most of the waste does not fall into this category, and some of the more sensational articles do not make clear the distinction.
That's not to say that there is not some nasty stuff at sellafield that needs to be stored properly, but compared to disposal of some of the nasty chemicals we make, it is a more tractable problem, and these days far better controlled than it was in the early days.
10,000cubic metres is equivalent to a tank 100m by 100m and 1m deep. For the whole country, not such a lot, indeed it would all fit in the car park at work for example. Mind you, I'd be a bit hacked off if they did that - I'd have to park somewhere else ;-) .
Mike.
Mike.
We're about to take you to the IET registration website. Don't worry though, you'll be sent straight back to the community after completing the registration.
Continue to the IET registration site
