Redbridge Causeway

This job involved the completion of an offshore factual ground investigation (GIR) comprising three sonic boreholes, Unexploded Ordnance (UXO) clearance and environmental controls.

The main objectives of the programme were to:

  • Identify and confirm suspected sources of contamination, providing sufficient data to determine suitable remedial measures.
  • Determine the type, strength and bearing characteristics of the shallow superficial deposits and underlying solid geology.

Terra Firma (South) were required to provide innovative solutions to working under difficult conditions, in order to produce a factual ground investigation for the site. This involved the procurement of a mobile  pontoon, capable of carrying various types of rig onto different hole locations. UXO clearance works were scheduled, due to the location history, prior to the commencement of drilling. Utilising the latest in drilling advancements, a sonic drilling rig was used for its speed and sampling quality capabilities.

With the time restrictions associated within a tidal off-shore environment, Terra Firma (South) was able to offer the option of off-peak site works in order to maximise the natural site accessibility. In addition, sensitive environmental constraints, linked with the local salmon population and migrating birds, were mitigated using noise level calculations and efficient time planning respectively, in order to minimise the disturbance of the local biological communities.

Working in an off-shore environment, ensuring works are carried out safely as possible is as important as ever. By submitting detailed RAMS documents and relevant methods statements, Terra Firma (South) ensures the safety of all workers as a priority, no matter the working conditions.

The public perception of the site works were also managed verbally, with Terra Firma (South) engineers taking time to explain the cause of the works and how their effect will provide a long-term benefit to the local area.