Detailed Investigations of Heavily Contaminated Site
Since 1997, Hemmera teams have been actively engaged in ongoing investigations of this site, which is contaminated with heavy metals and acidity. The results of our innovative technologies are providing useful data for the risk assessments that are essential to advance the project to the next phase.
The contaminated area contains soils, ground water, surface water and sediments that are contaminated with heavy metals, elemental sulphur, and land-filled materials. Our investigations have included soil test pitting, boreholedrilling, long-term groundwater monitoring, surface water and foreshore groundwater seep sampling, air quality and dustfall monitoring, occupational exposure monitoring, and sediment sampling.
Our teams pioneered the use the use of low-flow groundwater sampling—a technique that has since become prevalent in the industry. We installed multi-port precision sampling wells to provide finely-spaced vertical groundwater samples, which made it easier to identify the pathways of contaminant flow, and to detect changes in the groundwater’s chemical characteristics as depth increased. We collected and evaluated data on the site’s soil stockpiles and their potential to generate acid now or in the future. To manage the extensive environmental data, we developed an environmental database.
We applied our in-house GIS capabilities to provide three-dimensional visualizations of the site’s historical fill, contamination distribution, and to help with planning soil remediation. We also assisted in the development of a numerical groundwater transport model using ModFlow, a 3D groundwater modelling software system.