FSCL’s work scope was to secure the substation’s supporting jacket structure to the seabed after it had been lifted into place by Scaldis using the heavy lift barge Rambiz. Working from FSCL’s jack-up barge Excalibur, the 850t jacket was initially secured by driving four 1370mm OD x 35mm WT tubular steel lead piles through the jacket's legs using a 92t S600 impact hammer. Follow on sections were then welded in-situ to the lead piles before driving through the chalk seabed. Driving analyses were carried out by Fugro France with results available to the client to study in real time, allowing decisions to be made in the field as to when driving should be terminated.