Subcon Europe NV was awarded the Brighton Marina Caisson Remediation Project. This was aimed to upgrade the breakwater to improve strength and durability. In the first phase bulk remediation grouting was carried out on 10 caissons that formed part of the Brighton Marina East Breakwater. For the second phase, Subcon proposed a complete solution, including all marine, dredging and batching spreads required for the removal and recylcing of existing caisson ballast as welll as the injection of over 8000m3 of concrete.
Subcon required works to continue 24/7 due to the time constraints of undertaking the project in a working marina. They required long reach machines to assist with the removal of the gravel from existing caissons and to lunload the gravel to be mixed with cement and then pumped back into the caissons.
WM Plant Hire supplied 2 long reach machines. A 30 tonne Case 250 was situated on a jack up barge and fitted with a pole grab which could excavate the gravel to the 10 metre caisson depth. This excavator loaded the material into a barge which was then transported to another part of the marina, where a 25 tonne long reach unloaded it prior to being mixed with cement and pumped back into the caissons.