There are a variety of trace element contaminants released by geothermal systems, and by the weathering of mineral deposits, which can damage aquatic ecosystems if they find their way into freshwater streams, rivers and lakes. For geothermal systems, the most common of these contaminants are; arsenic, antimony, mercury, lithium, boron and sulphide. For mineral deposits, the type of trace element released depends on the nature of the ore deposit, but common elements of concern include arsenic, mercury, copper, lead, zinc, cadmium, iron, manganese and aluminium.
Unless steps are taken to minimize or avoid trace element release, the development of a geothermal system or the mining of a mineral deposit can lead to an increase in the concentrations of trace elements in nearby drainage systems. The toxic effects that these elements have on aquatic animals and plants, crops or people can be significant if the concentrations become high enough.
We have experience in predicting the likely fate and environmental impacts of trace elements released into freshwater systems, and in technical or peer review of AEE documentation relating to water quality issues for geothermal development and mining activities.