Foundation Works Risk Assessment Allows Development to Proceed
Ruddlesden geotechnical were commissioned to undertake a Foundation Works Risk Assessment for a proposed commercial development within the centre of Cirencester. The development was to include the installation of piled foundations to support the proposed buildings.
The Environment Agency were concerned that the installation of the piled foundations could mobilise contaminants within an overlying thickness of made ground into the underlying Secondary A Aquifer (Forest Marble Formation) and potentially cause contamination to the water environment.
Ruddlesden produced a Foundation Works Risk Assessment in accordance with the Environment Agency’s published guidance document. This included the production of a detailed conceptual site model (CSM) and identifying the potential scenarios and pollutant linkages that could occur as a result of the piling works.
The risk assessment suggested that the piling contractor’s chosen piling method could foreseeably cause contamination of the underlying aquifer, as a result of displacing/ pushing contaminated soils down into it.
Following the risk assessment, an alternative (non-displacement/ replacement) method of piling was proposed which would mitigate the risks of contaminating the underlying aquifer. This risk assessment was approved by the Environment Agency and local authorityand allowed the works to continue as proposed.