Objectives:
This project aims to develop a practical hazard screening and classification system for heap and dump leach facilities, addressing the growing concern over catastrophic slope failures in these operations. The mining industry is increasingly constructing taller, steeper, and higher-risk heaps, yet no standardized geotechnical risk assessment framework currently exists. Existing guidance, such as the 2017 Guidelines for Mine Waste Dump and Stockpile Design, is widely used but was designed for waste dumps and does not fully account for heap-specific conditions, including drainage, saturation, material behavior, and operational phasing.
The proposed whitepaper will adapt the proven Chapter 3 framework of the 2017 guidelines to heap leach operations. It will incorporate screening criteria for critical failure modes such as static and dynamic liquefaction, pore-pressure-induced deformation, and slope instability under saturated conditions. The tool is intended to provide mine operators, engineers, and regulators with an immediate, easy-to-use reference for project screening and for scoping follow-on studies, enabling proactive risk management. The whitepaper will later become a core chapter in the planned comprehensive guideline, “Guidelines for Heap and Dump Leach Design and Operation.”
The project will leverage the extensive experience of the authors in heap leach design, review, and failure investigation, including direct involvement in updating corporate standards following recent failures. The approach focuses on adapting the existing framework, integrating emerging failure modes, and tailoring the screening system for gold and copper heap leach operations, with potential future expansion to uranium, nickel, and other commodities.
Key deliverables will include a hazard rating matrix, risk classification tiers (Low, Moderate, High, Extreme), trigger thresholds for further investigation, recommended monitoring and mitigation strategies, and anonymized case examples. The outcome will be a practical, standardized tool that enhances safety, operational resilience, and risk-informed decision-making in heap and dump leach operations, addressing urgent industry needs and providing a foundation for future comprehensive guidance.
This project was completed in mid-2025. The resulting whitepaper features comprehensive tables and is accompanied by a macro-enabled Excel spreadsheet for hazard classification. The classification system has been calibrated using data from approximately 100 heap leach facilities worldwide and incorporates feedback from sponsors and industry experts, covering the full spectrum of hazard levels.