Brownfield infrastructure projects are seeing geotechnical and environmental teams urged to integrate ground investigation, contamination data and 3D ground models from the outset, rather than running parallel site characterisation workflows. The piece stresses unified digital datasets combining borehole logs, in situ test results and contaminant plumes to refine ground risk registers, optimise foundation and earthworks design, and avoid late-stage remediation surprises. Case experience shows that early joint modelling of variable made ground, buried obstructions and legacy industrial pollution can materially cut unforeseen ground conditions claims and programme delays.

Rock & Alluvium, part of Van Elle, has installed its deepest continuous flight auger piles to date, reaching 40m, for the Bow Green development in East London. The record-depth CFA piles indicate challenging ground conditions and high load or settlement performance requirements typical of dense urban sites near the Thames. Contractors and designers may need to consider comparable pile lengths, rig capabilities and spoil management strategies for future high-rise or mixed-use schemes in similar London alluvial and made-ground profiles.

Helical piles are presented as displacement deep foundations that can be installed with small hydraulic drive heads on mini-excavators or skid steers, generating minimal spoil and vibration compared with driven piles. The FAQ addresses load capacity verification via torque correlation (e.g. kN-m per kN of capacity), corrosion protection options such as hot-dip galvanising and increased sacrificial thickness, and suitability in soft clays, fills, and below groundwater. Design is framed around ICC-ES AC358, with emphasis on tension, compression, and lateral performance for underpinning, boardwalks, and utility structures.