Coal tar was found beneath the Site at depths ranging from just below the surface to 13.5 m below ground level (bgl). This coal tar was discovered both above and below the water table, at a depth of approximately 4.5 m below ground level (bgl), and has the potential to pose risks to human health and the environment. Through conceptual remedial design and laboratory trials, In Situ Solidification (ISS) was identified as the preferred remediation technology to address the gross coal tar impacts at depths from approximately 3 m to 13.5 m bgl.
To further assess the suitability of ISS as a remedial technology for the Site, an ISS Pilot Trial was required and carried out by specialist contractor Menard Oceania. Menard completed the trial scope including installation of work platform, set up and installation of 9 no. 1.5m diameter columns to 8m deep and complete demobbed from site in 2.5 weeks ahead of schedule.