Aurecon

PFAS Site Investigation — Saving $20M

Aurecon conducted a detailed site investigation at a large facility dealing with perfluoro-alkyl substances, producing geological, soil, groundwater, and remedial volumetric models with Earth Volumetric Studio. After the client requested more detailed volumetric modelling of a particular source area, the results revealed a much lower overall contaminant mass in soil than had previously been assumed. More importantly, the model clearly showed no connectivity between the soil contamination and the groundwater. The groundwater was still contaminated, so the only possibility was that soil in the saturated zone was the source — which later investigation confirmed. The client had been about to approve a $20 million expenditure for a groundwater treatment plant, which in light of the volumetric model would not have been value for money and would not have addressed the actual source of the problem. Aurecon is now investigating immobilisation of the saturated zone contamination as a more targeted alternative. As a follow-on, Aurecon presented geostatistical analysis and a 4D model of the same site to a related agency. Previously, no consultant had gone anywhere near calculating total contaminant mass on a site, let alone presenting measurements of confidence and uncertainty — and this had been a major issue for the agency in planning and conducting remedial works. The agency instantly recognized the applicability of Studio to their remedial planning and prioritisation challenges, and the work has since been elevated to senior management attention.

"Within minutes of starting the presentation, the agency's technical director said 'this is what I've wanted all along.' None of this would have been possible without EVS. The modularity of Studio is especially popular and the staff who have done the training find it really simple and easy to understand. Along with the powerful interpolation methods it employs, Studio is becoming our preferred tool for delivery of contaminated land projects and is catalysing a change in our investigation methodology."