Senior Hydrogeologists, Deborah Thomas and Penny Jenkinson were pleased to share their expertise at The Geological Society of London’s Hydrogeology of the Superficial Deposits Conference.
The variable nature of superficial deposits means that they typically have complex relationships with their hydrogeological surroundings. The lithology of the deposits can vary considerably, both horizontally and vertically, and depending on the setting, superficial aquifers can take the form of extensive layers, discontinuous lenses or channels. Due to their frequent groundwater-surface water connectivity, there is a high potential for environmental impacts from developments to be observed in surrounding surface water features as well as the wider superficial aquifer.
Sand and gravel deposits are an important resource in the UK being a key target for shallow mineral extraction. They are also an important aquifer providing useful water supplies. Correctly classifying the type of deposit will influence the working method and on-site water management for mineral extraction, and also the siting of abstraction boreholes.
A range of methods can be employed to investigate and establish the type of superficial deposit present at a site. These include non-intrusive techniques like geophysical surveys and intrusive techniques comprising borehole drilling and geotechnical investigations. Groundwater level monitoring can also be used to characterise deposits and assess any impacts from developments on the surrounding water environment.
Deborah and Penny presented case studies on a range of mineral extraction and water abstraction developments, showing how the type of deposit influences the siting and design of abstraction and monitoring boreholes.
The presentation has been uploaded to Envireau Knowledge – a free library of useful resources available on our website here.