GEA were appointed to carry out a desk study and phased investigation for the redevelopment of a run- down industrial site in Trumpers Way, Hanwell through the construction of a co-location scheme providing modern, light and flexible work space, together with 205 apartments and eight townhouses in three buildings.

The site comprised a range of units with independent tenants running vehicle repairs, scrap yards, joinery and light engineering among other uses. The desk study research had highlighted a historical landfill in the vicinity and a long history of light industrial use on the site. The scope of the investigation was limited by the presence of the buildings and continued occupancy, such that fieldwork was carried out in three phases to cover as much of the site as possible. We initially carried out a preliminary contamination assessment, followed by geotechnical investigation and more detailed contamination study, including gas monitoring and groundwater analysis. The site is located on the eastern side of a flood plain for the River Brent and as such the ground conditions comprised a limited thickness of superficial soils over London Clay.

It was clear that any contamination from the site was most likely to be present in the upper layers of superficial soils and as such some form of soil removal was likely to be the best remedial option. In the early stages of the project, when the proposals had not been finalised, GEA advised that incorporating a basement into the development would have the benefit of maximising the potential for the site and removing future potential liabilities with regard to contamination. Once the site had been vacated, we returned to carry out sampling in previously inaccessible areas and to refine the remediation proposals. We will be on-hand as the development proceeds to keep a watching brief during the site clearance and basement excavation.