Delta-Simons was appointed by Hermes Property Asset Management to investigate and remediate a complex site in Basingstoke, which included a former manufacturing and chemicals works, an operational dry cleaning facility and a former waste dump.
Purpose
The site was located on a Major Aquifer and within a source protection zone (SPZ). The dump received waste from the Thorneycroft Works, which included cyanide in the form of sodium cyanide, tipped in clusters of drums, loose drums and as a loose material in an indiscriminate way within the tip.
The dry cleaning facility activities had resulted in chlorinated solvents entering the Major Aquifer and the manufacturing site had similarly caused hydrocarbon & solvent contamination to impact soil & groundwater. The Thorneycroft Works was to be sold for retail redevelopment.
Outline / Scope of Works
Our team carried out detailed ground investigations and worked closely with the Environment Agency and Thames Water to agree remediation targets, prior to carrying out remediation of a solvent plume via pump and treat technologies. The cyanide tip required special health & safety measures to be in place during the investigation.
Following risk assessment, remediation of cyanide hotspots was successfully carried out.
Outcome
Our long involvement in this project enabled a consistency to the management of the risk to a nearby potable water supply. Our careful approach to the unique risks posed by the cyanide tip enabled all works to be carried out safely.
The remediation system was successfully incorporated into the design of the retail scheme and operated during and after construction.