Authors: Dick, G; Nunoo, S; Smith, S; Newcomen, W; Kinakin, D; Stilwell, I; Danielson, J

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Dick, G, Nunoo, S, Smith, S, Newcomen, W, Kinakin, D, Stilwell, I & Danielson, J 2020, 'Monitoring and managing large deformation pit slope instabilities at a British Columbia copper mine', in PM Dight (ed.), Slope Stability 2020: Proceedings of the 2020 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering, Australian Centre for Geomechanics, Perth, pp. 439-452,

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Pit slopes exhibiting large deformations due to weak and complex fault zones within an otherwise good quality rock mass are characteristic of an open pit mine in British Columbia, Canada. Following the introduction of a database with 26 pit slope instabilities, the paper describes one of the instabilities, which exhibited over 70 m of cumulative deformation over the course of one year without collapsing. Ground-based slope stability radar and prisms surveyed by a robotic total station continuously monitored the pit slope deformation rates as the instability area experienced acceleration events lasting several days as mining of the high slope progressed towards its final height of 320 m. Integrating ground-based radar and surface deformation monitoring with drone photogrammetry was instrumental in understanding the complex failure mechanism and successfully managing this instability.

Keywords: pit slope deformation monitoring, slope stability radar, slope instability database

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