Hamman, ECF, Cowan, M, Venter, J & de Souza, JB 2020, 'Considerations for open pit to underground transition interaction', 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. 1123-1138, https://doi.org/10.36487/ACG_repo/2025_74
A large volume of work is available in the industry on many aspects relating to the interaction between open pit and underground mining. Various authors have addressed the optimisation of the transition problem to determine the optimal economic point to transition from open pit mining to underground mining. Several papers have been presented on determining a suitable crown pillar to eliminate or minimise the interaction between open pit and underground mining, and several authors have presented on discrete, geotechnical interaction and challenges that were faced on certain mines.
There is, however, very little information available that has been collated into a suitable reference or guide for designers and practitioners to consult on the potential operational challenges that a mine may face. Thus, the need for robust due diligence processes/techniques, which can function as part of a mine’s planning strategy, becomes essential to identify hazards that can impact production and amelioration options to mitigate and manage the risks.
These will be unique to the sequence of the open pit underground interaction, which can take any combination of the following forms:
This paper provides an introduction in contextual information that practitioners, having to deal with open pit underground interaction, need to consider.
Keywords: transition, open pit underground interaction, risk management, operational considerations
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