Contreras, L-F, Hormazabal, E, Ledezma, R & Arellano, M 2019, 'Geotechnical risk analysis for the closure alternatives of the Chuquicamata open pit', in J Wesseloo (ed.), Proceedings of the First International Conference on Mining Geomechanical Risk
, Australian Centre for Geomechanics, Perth, pp. 373-388.
The development of the geotechnical risk model for the Chuquicamata mine started in 2005 and included the safety and economic impacts of slope failures at different scales (Tapia et al. 2007; Steffen et al. 2008). The model has been updated recently to include a quantitative evaluation of large economic impacts derived from inter-ramp and overall slope failures using a probabilistic approach (Contreras 2015). This paper describes how the later component of the model was used as a tool for the evaluation of four closure alternatives for the open pit. The methodology included three main tasks:
2. Evaluation of the consequences of slope failure associated with economic losses derived from impacts on production and costs.
3. Generation of risk maps to compare several closure alternatives.
The results of these analyses provided information on magnitude of impacts and their likelihood for the four closure alternatives evaluated. The evaluation of these results facilitated the selection of the appropriate closure alternative considering the mine reference criteria for economic risk.
Keywords: risk model, risk map, slope stability analysis, economic impact of slope failure.
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