Chemical Oxidation to remediate chlorinated benzene in a chalk aquifer
BAM Nuttall commissioned us to assist them in the remediation of a plume of groundwater contaminated with chlorinated benzene. The contaminated water was 15m below ground level in a chalk aquifer and next to major river in the south of England. Geoenvironmental’s initial task was to develop the remediation strategy and gained agreement from the Environment Agency. The strategy included the use of a strong chemical oxidant to reduce the concentration of chlorinated benzene within the plume and subsequent sampling and analysis of groundwater to show that natural attenuation was taking care of the residual contamination following treatment.
We chose to use Peroxychem’s Klozur® CR as the chemical oxidant and this was activated with sodium hydroxide, a strong alkaline. The chemicals were combined as they were pumped into the boreholes.
Following chemical treatment, we only had to monitor the groundwater for 6 months to gather enough data to provide supportive evidence to show the Environment Agency that natural attenuation was taking place and sign off was achieved.