Authors: Narendranathan, S; Cheng, M

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Narendranathan, S & Cheng, M 2019, 'Development of the Mine Geotechnical Risk Index', in J Wesseloo (ed.), MGR 2019: Proceedings of the First International Conference on Mining Geomechanical Risk, Australian Centre for Geomechanics, Perth, pp. 461-474,

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The authors have developed the Mine Geotechnical Risk Index (MGRI), which has been advanced to attribute tolerable thresholds of risk in a given transitional mine closure context. This paper presents the philosophy behind the development of the MGRI using a conceptual case study and sets out how the authors propose it could be applied by practitioners in particular scenarios only when assessing tolerable thresholds of risk. The reader should note that this approach is not intended to replace conventional engineering risk assessments, it is merely an alternative method in evaluating the ‘tolerability’ of elevated risk thresholds.

Keywords: Probability of Failure, Factor of Safety, geotechnical risk index, slope stability, circular failure, coal sliding, acceptable risk, brown coal, pit lake, mine rehabilitation

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