Erosion and Sediment Control

Associate Professor Claire Côte, Director of SMI's Centre for Water in the Mineral Industry (CWiMI), and Group Leader of the Environmental Excellency through the Mining Cycle,  discusses her work in Erosion and Sediment Control.

Water is increasingly recognised as a material risk by mining companies. Corporate water management strategies are being developed but tend to be heavily focused on access to water for production and processing. This does not necessarily capture the most severe water-related risks.

Stormwater runoff generated by mine sites still constitutes a core environmental risk. Mine-affected runoff often contains contaminants that threaten the health of the receiving environment. Sediments and suspended solids are a major cause of ecological degradation in freshwater ecosystems. Elevated salinity is recognised as being a key contributor to the toxicity of many mine-affected waters. Low pH and elevated concentrations of sulfate and trace metals are other well-documented causes of mine water environmental toxicity. Stormwater management follows standard principles but must be adapted to local regulatory frameworks, which are continuously evolving.

In this webinar, Claire will present the example of the Queensland regulatory framework to discuss the difficulties associated with managing stormwater runoff. The framework was developed after the impacts from serious floods were analysed. It recognises that run-off flows that do not come into contact with the mine’s activities can be considered high-quality water that can be passively released to the environment, provided adequate erosion and sediment control structures are in place. In practice, this means that mine-affected and non-mine-affected flows must be effectively segregated and that sound principles of erosion and sediment control must be established. With the Queensland government implementing the Reef 2050 Water Quality Improvement Plan, there is greater pressure on coal mines to strengthen their control measures.