Generally, there are four main mining activity impacts on water quality:10 Acid mine drainage exposes sulphides in rocks to air and water, creating sulphuric acid. Leached sulphides can be carried through the watertable or by rainwater surface run off, severely affecting local waterways and aquatic ecosystems. Heavy metal contamination and leaching can occur when mined metals come into contact with water and move into waterways and watertables, affecting drinking water supplies and aquatic ecosystems. Processing chemicals such as cyanide and sulphuric acid can be used in extractive mining activities to separate minerals from the parent rock. If not contained in tailings dams, these chemicals can have significant impacts on humans and wildlife if they enter the local groundwater and waterways. Erosion and sedimentation must be actively managed by mine operators throughout the mine’s life and after rehabilitation to reduce any offsite impacts, especially in heavy rainfall events or if tailings dams burst. Tailings storage facilities Tailings storage facilities (TSFs), also called tailings dams, are impoundment structures for disposing of the fine grained slurry waste stream that is left over from mining, and crushing and processing activities. The design and siting of TSFs is highly specific to a mine and will depend on the mine’s scale, nature and local geography. Serious environmental incidents around the world and in Australia highlight the potential immediate and long term risks of TSFs, particularly relating to their structural integrity and stability (box 17.3). TSFs need to be managed safely and in an environmentally responsible manner during operation. They also need to have appropriate plans for their closure and rehabilitation when operations cease. The case for change Throughout our consultations, stakeholders raised concerns about the current regulatory arrangements for the mining industry in Victoria. They were particularly concerned about the potential conflict of interest in having the primary mining regulator ERR reside in the – – Department of Economic Development, Jobs, Transport and Resources, which seeks to foster and develop the mining industry.
Generally, there are four main mining activity impacts on water quality:10 Acid mine drainage exposes sulphides in rocks to air and water, creating sulphuric acid. Leached sulphides can be carried through the watertable or by rainwater surface run off, severely affecting local waterways and aquatic ecosystems. Heavy metal contamination and leaching can occur when mined metals come into contact with water and move into waterways and watertables, affecting drinking water supplies and aquatic ecosystems. Processing chemicals such as cyanide and sulphuric acid can be used in extractive mining activities to separate minerals from the parent rock. If not contained in tailings dams, these chemicals can have significant impacts on humans and wildlife if they enter the local groundwater and waterways. Erosion and sedimentation must be actively managed by mine operators throughout the mine’s life and after rehabilitation to reduce any offsite impacts, especially in heavy rainfall events or if tailings dams burst. Tailings storage facilities Tailings storage facilities (TSFs), also called tailings dams, are impoundment structures for disposing of the fine grained slurry waste stream that is left over from mining, and crushing and processing activities. The design and siting of TSFs is highly specific to a mine and will depend on the mine’s scale, nature and local geography. Serious environmental incidents around the world and in Australia highlight the potential immediate and long term risks of TSFs, particularly relating to their structural integrity and stability (box 17.3). TSFs need to be managed safely and in an environmentally responsible manner during operation. They also need to have appropriate plans for their closure and rehabilitation when operations cease. The case for change Throughout our consultations, stakeholders raised concerns about the current regulatory arrangements for the mining industry in Victoria. They were particularly concerned about the potential conflict of interest in having the primary mining regulator – ERR – reside in the Department of Economic Development, Jobs, Transport and Resources, which seeks to foster and develop the mining industry.
11370-DELWP-InquiryReport_Word-Version_PART-C.docx