Supporting the Energy Transition:
Delivering Complex BESS Ground Investigation in Winter Conditions
Key GeoSolutions recently completed a complex three-week ground investigation on an undeveloped site in Yorkshire, supporting the development of a future Battery Energy Storage System (BESS). The project demonstrated the importance of robust investigation, experienced site management and clear geotechnical interpretation – particularly when historical mining, harsh weather and difficult ground conditions combine…
Managing Complex Risks on a Live Site
Desktop studies confirmed historical coal mining beneath the site, requiring careful planning and compliance before intrusive works could begin. A permit to dig was obtained from the Coal Authority, ensuring all operations met regulated requirements for disturbing coalfield land.
Once on site, the project brought a series of operational challenges:
• Steep sloping agricultural ground, with gradients reaching 10%
• Freezing temperatures and heavy snowfall obscuring marked locations
• Drilling rigs freezing and equipment breakdowns in sub-zero conditions
• Thaw-induced mobilisation issues as meltwater accumulated downslope
• Rising groundwater levels resulting in blowing sand during windowless sampling
Despite these conditions, Key GeoSolutions maintained safe, coordinated supervision of three subcontractors operating simultaneously, ensuring progress continued without compromising quality or safety.
Comprehensive Ground Investigation Methods
The intrusive investigation comprised 22 exploratory locations, designed to characterise the site’s varied ground profile. Multiple methods were deployed, including:
• Rotary drilling (open hole and rock cored)
• Cable percussive drilling
• Windowless sampling
• Machine-dug trial pits
Each location was logged to BS 5930:2015, with geotechnical and environmental samples collected across bulk bags, tubs, U100s and rock cores. In-situ SPT testing supplemented the sampling to provide further insight into material behaviour.
Developing the Ground Model
The results of the investigation were consolidated into a full Interpretive Ground Investigation Report (GIR). This included:
