Wales - Subregion 3

National Geological Screening for a GDF - Wales region


Wales, subregion 3

Our work shows that we are unlikely to find enough suitable rock to accommodate all of the waste in this subregion, although sufficient suitable rock to host part of it may be found.

Rocks are present at the surface over much of the subregion, including the sea cliffs on the Gower peninsula and the Pembroke coast and cliffs in the upland areas such as the Brecon Beacons. Combined with some deep boreholes and geophysical investigations, particularly in the coalfield areas, this gives us an understanding of the rocks present and their distribution.

There are various types of gaps in our understanding of geology and we deal with these gaps in a number of ways.

Our work has identified no rocks in which it is likely that a GDF could be sited under this subregion.

Some of the subregion has been mined for coal resources to depths below 100m, mainly in the South Wales coalfield in the valleys north of Cardiff and Swansea, but also to a much lesser extent in Pembrokeshire. In these areas the mining is likely to have affected the way in which water moves through the rock. Also possible exploration in the future in these areas means that it is more likely that future generations may disturb a facility.

Parts of this area, related to coal bed methane for parts of the coalfield and its southern margin and along the coastline between Newport and Chepstow, have Petroleum Exploration & Development Licences to allow gas companies to explore for oil and gas. This exploration is currently at an early stage and it is not known whether oil or gas in these licence areas will be exploited. RWM will continue to monitor how this exploration programme progresses.

Parts of this area, associated with the South Wales Coalfield, 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 also continue to monitor how this exploration programme progresses.

There are thermal springs at Taffs Well, 10km north of Cardiff, which indicate that groundwater is moving rapidly from depth to the surface in these areas. This would need to be considered in the siting of a GDF in this subregion.

For further information, read the report below.

Wales Subregion 3

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We have also produced a summary of the geological attributes of Wales.

Go to National Geological Screening for a GDF

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Published 19 December 2018
Last updated 16 January 2019 + show all updates
  1. Added translation in Welsh
  2. First published.