Rougier, M, de Graaf, PJH, Desjardins, M, O'Leary, M, Yugo, N & Kilbride, B 2020, 'Managing ice walls and other operational challenges while optimising
Victor Mine late stage opportunities', in PM Dight (ed.), Proceedings of the 2020 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering
, Australian Centre for Geomechanics, Perth, pp. 255-264, https://doi.org/10.36487/ACG_repo/2025_12
This paper discusses the engineering, hydrogeology, operational practices and TARPs that facilitated deeper mining and goodbye cuts at the De Beers Canada Victor Diamond Mine. A number of technical challenges related to water management and adverse geology late in the mine life were overcome in order to successfully meet and exceed the planned mining depth. Extensive pit dewatering and a pit water management program were implemented not only to maintain dry working conditions for operations but to ensure highwall stability and reduce the formation of hazardous ice columns along the highwalls. After a 15 m tall ice column failure, bench design was optimised to ensure perched aquifers occurred as low on the highwall as possible. Where the uppermost ice columns formed, strategic reinforced meshing was installed to eliminate the possibility of sudden ice column failures that could not be predicted with the monitoring systems in use. Excellent limits blasting outcomes and better than expected conformance to design also allowed for inter-ramp limestone slope optimisation. Additionally, a ‘ploughing’ style failure mode was of concern due to blocky limestone underlain by saturated clays and mudstones. Here, a pit redesign and highwall depressurisation thresholds were used to prevent this failure mechanism from occurring, as well as developing vibrating wire piezometer trigger action plans. The overall results of the integrated hydrogeological and geotechnical designs and slope management practices were positive and contributed significantly to slope design optimisation and safely recovering additional ore. What worked technically and in terms of people and procedure are shared.
Keywords: TARP, trigger action response plan, ice, icefall, mesh, slope depressurisation, slope optimisation, blasting, goodbye cut, slope stability, Severn, Red Head Rapids, Attawapiskat, sump, Hudson Bay Lowlands
Konya, CJ 2006, ‘Rock Blasting and Overbreak Control’, International Society of Explosives Engineers.
Rougier, M & Smith, J 2017, Development of Piezometer Dewatering Targets for the Victor Mine Ultimate Pit Slope Designs, Golder Associates Ltd, De Beers Canada Victor Mine, pp. 29.