Environmental Intelligence in Mine Closure and Reclamation


Elizabeth Haack, EcoMetrix Incorporated; Sarah Barabash, EcoMetrix Incorporated

Mine life cycle management benefits from risk management at every stage. Risk management models and tools are well-established for traditional notions of health, safety and the environment (e.g., risks to worker health; geotechnical risks associated with mine infrastructure).  However, management of more nuanced considerations, such as risks to ecological and human health posed by environmental exposure pathways, has not yet reached the same level of maturity industry-wide. We advocate that the best approach for assessment of risks to human and ecological health through the mine life cycle is one that builds on tools already being used for decision-making and planning. Over the last several years, we have been applying an integrated approach - whereby site-wide constituent loadings are modelled and paired with quantitative human health and ecological risk assessment (HHERA). In this presentation, we will use recent case studies in support of mine closure planning to demonstrate the environmental intelligence gained through the risk-based approach.   For the sites evaluated, current conditions and source terms were established, and future mine closure and reclamation options were simulated using MineModTM. MineModTM is our in-house water quality management platform, with the unique ability to evaluate closure scenarios in real-time in an intuitive and visual manner. HHERA was then used to identify site aspects that contribute meaningfully to risks and key areas of regulatory and public interest.  Closure and reclamation options were ranked/prioritized on the basis of the predicted risk profile. Specific design criteria and targeted mitigation strategies were then developed, and key performance indicators defined to evaluate post-closure performance. This approach has allowed source areas that contribute meaningfully to risks to be distinguished from those that do not. It has supported site managers in making and communicating proactive decisions that reduce liabilities.
Keywords: Closure, Reclamation, Risk-based approach, options assessment, water quality, human and ecological risk assessment, liability reduction