(30 January 2013, 20:26)I-K-E Wrote: just a note London Clay is actually a very good medium for storing nuclear waste as it creates a barrier to radio nucleotide escape
It is a brilliant barrier, but then is any rock that is stable using the depth that would be used for storage.
With the differing strata of London clay and chalk down south, I think the land surface can easily move 20mm in a year due to the wetting and drying of the chalk. It is not as stable as most of the deep rock strata in the North West.
The area has a very thick layer of igneous rock without masses of sedimentary rock sitting on top of it so it does have the kind of strata that you would want to look at.
It is the lower maintenance option, as you stated.
(30 January 2013, 20:33)bigpaul Wrote: the trouble is, we havent had nuclear for 100,000 years-we've only had it for about 70 years so how do they know? its only theory, i prefer to be "safe, not sorry".
We - well, anyone that has knowledge of geology to a decent level - knows that the rock there is safe and stable. Hundreds of thousands of years is nothing really in geological time - it is a small fraction of time of the existence of this rock strata.
A lot of the fear around the scheme and a lot of stuff in general is not understanding it. Rocks only degrade due to outside forces. In nature, these forces are weathering or tectonic forces. For them to weather to the depth to cause a problem, it would take tens of millions of years.
With regards to tectonic activity, while we do have some in the UK and the Lake District, we pretty much sit in the middle of the Eurasian tectonic plate and so they are very small.
(30 January 2013, 20:55)I-K-E Wrote: Some parts of waste the will be active for about 100,000 of years the aim of a deep geological repository is safe storage for longer than that time with out humans to service it. No surface building will last anywhere near that amount of time. Better underground if the geology is right
Exactly - as it is now, if we keep the stuff stored as it is stored, it is good for several hundred years. Then we will have to re case it in much bigger modules than it is in now, and keep on doing this. Putting the cases it is in in geological storage and fixing it in place is the best option we have open to us now.
Sure, the stuff might be good for fission fuel, but that is at least 80-200 years off.