National Geological Screening for a GDF - Northern England
Our work shows that we may find a suitable geological setting for a GDF in much of this subregion.
Part of the subregion is the inshore area which extends to 20km from the coast, but rock can be seen at the surface inland and in man-made excavations such as quarries or road cuttings. Combined with some deep boreholes and numerous geophysical investigations, this gives us an understanding of the rocks present and their distribution.
There are clay-rich rock layers and layers of rock salt under most of the subregion in which we may be able to site a GDF. We would need to do more work to find out whether these rocks have suitable properties and thicknesses in the depth range of interest for a GDF.
Even where individual clay-rich rock layers are found not to be thick enough to host a GDF they may support the siting of a GDF in deeper rocks as they could act as a barrier to groundwater flow from depth. This is important because movement of groundwater is one of the ways in which radioactive material could be carried back to the surface.
Parts of this area, off the coast to the west of Whitehaven and to the north of Carlisle, are Coal Authority Licence Areas allowing companies to explore for coal. It is not known whether coal in these licence areas will be exploited. RWM will continue to monitor how this exploration programme progresses.
Parts of the Vale of Eden, which are mined for gypsum, would also need to be taken into account in the siting of a GDF, although the nature of mining in evaporites does not affect the movement of groundwater in the surrounding rocks in the same way as other mining.
For further information, read the report below.
We have also produced a summary of the geological attributes of the Northern England Region.