Hamman, ECF & Venter, J 2019, 'Using qualitative risk assessment as a leading indicator for geotechnical risk in mining', in J Wesseloo (ed.), Proceedings of the First International Conference on Mining Geomechanical Risk
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Investor confidence is largely driven by a mining company’s ability to deliver on the guaranteed return on investment. Thus, robust due diligence processes, functioning as part of a mining company’s corporate governance, become essential tools to identify hazards that can impact production, assess the associated risks and introduce controls to manage the risks.
The geotechnical practitioner is tasked to manage one of the biggest risks on the mine; that of a rock mass instability. Since an instability, or collapse, need not be large to have a significant impact on production, the challenge is to develop an optimised life-of-mine design with a risk management plan that suits the risk requirements of the mining company and investors, whilst meeting acceptable, minimum safety standards.
The concept of a Geotechnical Review Board has been adopted in the industry as a vehicle to provide assurance that the geotechnical risks on a mine have been identified and are being properly managed. The review relies on external parties providing appraisals of the design and processes, and experienced oversight of the active operations. In general, these reviews tend to have a unique style; often a combination of the current, visible, critical issues on the mine and issues deemed as important by either the reviewer or a third party. Coupled with the challenge of fluidity in modern planning environments, the geotechnical practitioner is often still faced with uncertainty in the level of geotechnical risk associated with any given mine plan.
This paper introduces a geotechnical risk assessment tool that has been developed for use as a leading indicator within AngloGold Ashanti’s international operations. The authors aim to provide the reader with insight into how the tool can be utilised to understand a mine’s ability to proactively identify and manage geotechnical hazards, by exploring the following components:
Keywords: risk management, leading indicators, event tree, qualitative risk assessment, reliability
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