THE CHALLENGE:
This former data centre car park was redeveloped from a timber yard in the 1980’s.
Extensive due diligence site investigation identified significant contamination of soil and shallow groundwater. Contaminants included a cocktail of Petroleum Hydrocarbons, BTEX compounds, Trimethylbenzenes, Pentachlorophenol and persistent Organochlorine pesticides (gamma-HCH (Lindane), aldrin and dieldrin) , which presented unacceptable risks to human health and nearby controlled water receptors.
Our Solution
Soilfix implemented a fast-track, multi-phase remediation approach including:
- Primary Remediation: Breakout of hard standing, removal of in-ground substructures, UST decommissioning/removal followed by targeted excavation of grossly contaminated shallow soils to reduce contaminant mass and satisfy risk-based human-health criteria. Sustainable off-site disposal to a permitted soil treatment facility;
- Secondary Remediation: In-situ Chemical Oxidation (ISCO). Injection of chemical oxidants PersulfOx® (activated sodium persulfate) and RegenOx® (sodium percarbonate) to rapidly reduce gross contaminant concentrations, within the saturated zone; and,
- Tertiary Remediation: Sorption and biodegradation. Injection of PlumeStop® Liquid Activated Carbon™ and locally Oxygen Release Compound (ORC-Advanced) to form a reactive groundwater treatment zone through
CONCLUSION:
Concentrations of the Principal Contaminants of Concern were reduced by >95% (comfortably exceeding the required objective >75%). The scheme successfully delivered remediation targets and the client was able to surrender the lease for the site within the required notice period, providing significant commercial savings on their lease.
