Assessment and Remediation of Phase Separated Hydrocarbons and Hexavalent Chromium Contamination

Project: Assessment and Remediation of Phase Separated Hydrocarbons and Hexavalent Chromium Contamination


Location: Camellia NSW


Client: Colas Australia


The Site currently operates as a bitumen manufacturing facility and has operated as an emulsion and bitumen manufacturing facility since the late 1940s.  Previous investigations conducted on the site identified a plume of phase-separated hydrocarbons (PSH) in the groundwater, likely as a result of the historical operation of an in ground drum wash bay and underground storage tanks.  The site also has been subject to historical filling activities.  Some of the fill materials placed onto the site is understood to have been sourced from a chromium chemical manufacturing company that operated on the peninsula from the 1940s through until the 1970s. Large volumes of chromium ore processing residue (COPR) were produced as a by-product of the operations and historical records indicated that COPR was used across the Camellia peninsula for filling activities as the industrial area developed. COPR is characterised by high concentrations of Cr(Total) and Cr(VI) in a high pH matrix due to the presence of residual lime used in the processing of chromite ore. Due to the presence of the PSH and Cr (VI) in the fill materials and groundwater on the site, the site is regulated by the NSW EPA under the Contaminated Land Management Act.


CONSARA was engaged as the contaminated land and remediation consultant to the Client for assessment, remediation planning and management of the PSH and Cr(VI) contamination.


The role comprised undertaking multiple stage soil, sediment, surface water and groundwater investigations; remediation design; remediation planning; remediation action plan preparation; remediation trialling; liaison and negotiation with NSW EPA and other regulatory and consent authorities; completion of reports required for planning approvals and to satisfy CLM Act regulatory agreement (VMP); NSW EPA Accredited Site Auditor review and approval;, remediation tendering; on-site supervision of contractors during remediation works; full scale PSH remediation system installations and operation; identification of any technical and commercial issues relating to the remediation contractors works; technical review of reports prepared by remediation contractor; post remediation work advice and validation works in relation to site completion works and management of long-term legacy issues.