Managing closure risks by integrating acid and metalliferous drainage assessments with mine scheduling - real world applications

摘要

Acid and metalliferous drainage (AMD) impacts may be a cause of significant long term environmental liabilities, as evidenced on many historic mine sites containing legacy AMD issues worldwide. These historical precedents have led to AMD being recognised as a key closure risk by industry and regulators, which in turn has driven progressive advances in geochemical assessment and management in recent times.Many AMD risks on a typical mine site are based on mineral waste management strategy and practice. By association, mine planning and scheduling may therefore have a significant bearing on the potential for AMD related closure liabilities. Despite this, the assessment of AMD risk is often packaged into the environmental approvals and management process, which is often not directly connected with the mine planning and scheduling process. Consequently, AMD assessments and management plans are frequently progressed by an approvals team that is often somewhat disconnected from the mine planning and scheduling team. Subsequently, AMD management measures may be conceived after the scheduling process has moved into a more advanced and less flexible phase. Sometimes, this may be the result of a lack of early co-ordination and/or budget leading to a lack of hard geochemical data with which to begin classifying potentially acid forming material.