Geocore Site Investigations was tasked by G.H. Saul Consulting Engineers to drill a 40-metre water borehole near Askham Bog with the primary aim of accessing and monitoring the Sherwood Sandstone aquifer. This project required careful consideration of the local geological conditions to ensure the borehole would meet the client’s needs and support future hydrogeological assessments. The site’s subsurface was characterized by approximately 30 metres of drift deposits sitting above the Sherwood Sandstone formation, which is known for its soft, grey, fine-grained yet competent rock properties.
The drilling process needed to account for the complex ground conditions, particularly as the standing water level was expected to be around 15 metres below ground level. Understanding these factors was crucial to determine the appropriate drilling approach and borehole construction techniques that would maintain structural integrity and prevent contamination. By thoroughly analyzing the geological profile, Geocore ensured that the methodology chosen would be both effective and safe for the environment and the equipment used.
For the operation, Geocore deployed their Comacchio 602 drilling rig, a machine well-suited to handle the precision and control required for working through the variable drift deposits and into the Sherwood Sandstone. The rig’s capabilities allowed for efficient penetration through the overlying material and accurate placement within the sandstone aquifer. This choice of equipment, combined with the technical expertise of the team, was instrumental in navigating the geological challenges posed by the site.
Ultimately, the project was successfully completed. The collaboration between expert planning, specialised equipment, and experienced personnel resulted in reliable infrastructure that G.H. Saul can now utilize for ongoing hydrogeological monitoring. This case demonstrates the importance of detailed site assessment and tailored drilling strategies in delivering high-quality water boreholes in complex geological settings.