In situ soil mixing was the delivery tool for lime activated Klozur® persulfate for the in situ chemical oxidation of chlorobenzene contamination.
Former Imperial Chemical Industries facility
RPS Planning & Development, Churngold Remediation Limited
Thornton, United Kingdom
MCB, DCB, TCE, PCE
The impacted area at the former chemical site included hotspots of elevated chlorobenzene (MCB), all isomers of dichlorobenzene (DCB), trichlorethene (TCE) and Tetrachloroethene (PCE), which when combined totaled just over .7 hectares. In situ chemical oxidation was chosen for treatment advantages in cost, timeframe and performance. In particular, a key receptor at risk was a non-tidal ditch that formed the northern boundary of the site.
Baseline mass balance calculations estimated that approximately 17,400 kg of contamination was partitioned in soil and NAPL, with a further 210 kg in groundwater. Calculations completed post remediation indicated that 11,715 kg of contamination was destroyed in situ as part of the process. Application of ISCO prevented approximately 48,400 tonnes of contaminated soil from being sent to landfill.
The rail yard site in Nijmegen, Netherlands has been subject to contamination via leaks, spills, and filling losses of hydrocarbon fuels over the years. Despite previous remediation attempts there remained residual TPH contamination. Following a successful bench test, a full-scale remotely controlled injection unit was used for implementation of alkaline activated Klozur® persulfate. The reduction of the TPH levels achieved the remedial goals in both the bench and fieldwork.
The selected remedy, soil mixing using in situ chemical oxidation (ISCO) combined with in situ solidification and stabilization (ISS) was used to destroy contaminants while stabilizing soils
Site Closed Following a Single Application of Klozur® SP and Hydrated Lime.
The approach was designed to remove the lower molecular weight compounds, which are the more soluble and mobile fraction of the contamination, via chemical oxidation while cementing the remaining higher molecular weight fraction of the tar in place. The addition of cement was also intended to activate the Klozur SP by generating alkaline conditions, significantly improving the kinetics of the ISCO reactions.
Specialty Earth Sciences, LLC was contracted to remediate a site that was impacted by residual coal tar by utilizing chemical oxidation methodologies.