Site selection : the international perspective and the role of geology
The government claimed in its 2008 white paper, Managing Radioactive Waste Safely: A framework for implementing geological disposal (Defra, Cmd 7386) that 25 other countries were opting for geological disposal, and mentioned Belgium, Canada, Finland, France, Germany, USA and Sweden. It stated:
“the UK Government policy is aligned with countries such as Finland, France, Sweden and the USA who have already made good progress towards implementing geological disposal.”
What the government does not say is that a geological suitability search came before any attempt to get communities involved, in all these countries. This is also true of Switzerland, which was not cited. The UK government is misleadingly implying that the so-called ‘success’ of these countries in progress towards finding a site was due to community support. This is not so.
It is true that at a late stage in the site search in both Sweden and Finland political considerations to some extent overrode the geology; but both these countries are unusual in having ancient hard crystalline rocks of a similar type at the surface over all of their low-lying regions. This means that the choice of an actual site was less important, because the geology was already constrained. This is not the case in the UK.
The search for a suitable site in the USA has been reset to zero with the closure of the Yucca Mountain research site in Nevada. Japan is not mentioned; investigations there were stalled in 2006. This benighted country is now belatedly doing its best to get out of nuclear, before it even begins to think again about nuclear waste disposal.
The hard rock sites selected in Sweden and Finland are relatively well-advanced, but the geology is complex. Contrary to simplified views, the rocks are not granite, but comprise highly altered rocks, formed deep down within the Earth’s crust, called gneiss. They are of granitic composition (hence the confusion), but are not granite. Granite itself is a simple crystalline homogeneous rock.
The site investigations are encountering problems at both Scandinavian sites due to the complexity, but at least the terrain is very flat, near the coast, so that there is very little pressure, or ‘head’, to drive the underground water flow through the cracks and faults. Again, this is far from being the case in West Cumbria.
Switzerland, France and Belgium are investigating sites in simple flat-lying clay formations with no faults, all in regions where the terrain is low-relief. The clay is more impermeable to water flow than crystalline rocks, and is also self-sealing if there is any disturbance.
But there remains the problem of what to do about escaping radioactive gas from a repository; no country has solved that one. Canada is pursuing a similar programme in Ontario. In the UK there are geologically similar areas in the east of England – but nowhere in West Cumbria.
Canada and Sweden have legislation to fund non-government groups to carry out independent research and checks on the progress of the site selection and subsequent subsurface works. Nothing like that is offered in the UK.
If the UK were to follow the international guidelines and international examples, it would:
- Find a choice of geologically promising localities.
- These would be areas of simple, predictable geology.
- The groundwater flow would be very low, in flat terrain.
- Communities would then be approached for support.
- The progress deciding on the preferred site would be transparent and unhurried.
- Opposition groups would be funded to criticize the whole process.
- There would then be no need for the confrontational process of a legal challenge, which is the way the UK government is heading.
More about geology in the UK
If you want to understand more about the role of geology in the search for a host site for deep disposal in the UK, you can watch Prof Stuart Haszeldine of Edinburgh University giving a lecture at the Geological Society in October 2008 — just follow the link
http://www2.geolsoc.org.uk/
and go to Stuart Haszeldine’s website to find out more about the sites in Copeland & Eskdale / Ennerdale http://www.geos.ed.ac.uk/homes/rsh/Allerdale_and_Copeland.html
and Prof David Smythe’s for detailed arguments and information about the geology of these sites and West Cumbria more generally http://www.davidsmythe.org/