In June 2002, Tony Gee and Partners (TGP) was appointed to carry out a full site investigation and private geotechnical advice on foundations and regeneration of a former gas works site adjacent to the River Thames in Thamesmead.

The planned development was to include two large residential blocks on the Thames riverside. These structures would require suitable foundations to be designed to overcome the layers of soft compressible alluvium present beneath the site.

The site was previously investigated by others in the 1970s following demolition of a former gas works. Following completion of the investigation, the area was capped with crushed concrete to prevent access to the contaminated soil.

This layer of crushed concrete was 1 to 2m thick and consisted of blocks of reinforced concrete slab up to 2m long. this low-tech solution from the past left issues that needed to be addressed using up-to-date techniques. Since the capping was placed the site has not been used.

the ground investigation was planned in two stages with an initial stage carried out to establish the outline levels of soil contamination and to remove the concrete obstructions from the proposed borehole locations. From this initial study and laboratory results, TGP was able to establish the correct working procedures to follow whilst carrying out investigations through contaminated soil as set down by the British Drilling Association (BDA). These procedures ensure the welfare and safety of site operatives as well as surrounding land users.

The main investigation comprised boreholes and trial pits to gain information of ground conditions beneath the site. From the findings foundation recommendations were produced including compliance with the Environment Agency's guidelines on foundations over aquifers.

The next stage of the project is to develop the now redundant dock into a landscape feature for the proposed residential development. Possible solutions include the use of lightweight fills and/or ground improvement to reduce settlements.