Authors: Hamman, ECF; Cowan, M; Venter, J; de Souza, JB

Open access courtesy of:


Cite As:
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,

Download citation as:   ris   bibtex   endnote   text   Zotero

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

Accreditation Board for Engineering and Technology1987, Fifth Annual Report, Washington, D.C.
Bar, N, du Plessis, P, Nicoll, S, Welideniya, S, Ryan, C & McAllister, P 2018, ‘Risk management strategies for open pit mining through historic underground workings’, Proceedings of 10th Asian Rock Mechanics Symposium, International Society for Rock Mechanics, Lisbon.
Barton, NR, Lien, R & Lunde, J 1974, ‘Application of the Q-system in design decisions and appropriate support for underground installations’, in M Bergman (ed.), Proceedings of the International Conference on Subsurface Space, Pergamon Press, New York, pp. 553–561.
Bieniawski, ZT 1992, Design methodology in rock engineering: theory, education and practice, Balkema, Rotterdam.
Bieniawski, ZT 1991, ‘In search of a design methodology for rock mechanics’, in E Roegiers (ed.), Proceeding of the 32nd US Symposium on Rock Mechanics, Balkema, Leiden, pp. 1027–1036.
Booth, PA & Hamman, ECF 2007, ‘Saprolites, structures and slope angles — applying site-specific geotechnical and mining knowledge to achieve the final design’, Proceedings of 6th Large Open Pit Mining Conference, Australasian Institute of Mining and Metallurgy, Carlton, pp. 25–33.
Brummer, R, Li, H & Moss, A 2006, ‘The transition from open pit to underground mining: An unusual slope failure mechanism at Palabora’, Proceedings of International Symposium on Stability of Rock Slopes in Open Pit Mining and Civil Engineering Situations, The Southern African Institute of Mining and Metallurgy, Johannesburg, pp. 411–420.
Butts, RA & Hague, PR 1998, ‘Locating dangerous historic mine workings in the cresson open-pit mine with the aid of ground penetrating radar’, Proceedings of 11th EEGS Symposium on the Application of Geophysics to Engineering and Environmental Problems, European Association of Geoscientists & Engineers, Houten.
Carter, T 2014, Guidelines for use of the scaled span method for surface crown pillar stability assessment, Golder Associates, Toronto.
Costa, LCB, Padula, RC, Pimenta, LMV, Pereira, RS & Peterle, DT 2019, ‘Support and reinforcement damage initiation and design adjustments in a deep mine environment - case study: Cuiaba Mine, Brasil, MG’, Proceedings of the Ninth International Conference on Deep and High Stress Mining, The Southern African Institute of Mining and Metallurgy, Johannesburg.
De Beer, CJ 2015, ‘Mining an open pit over and through old sub-level caving operations at Kwaggashoek East Open Pit, Thabazimbi iron ore mine’, Proceedings of the International Symposium on Stability of Rock Slopes in Open Pit Mining and Civil Engineering, The Southern African Institute of Mining and Metallurgy, Johannesburg.
Dunniclif, J 1993, Geotechnical Instrumentation for Monitoring Field Performance, John Wiley and Sons, New York.
Flores, G & Catalan, A 2019, ‘A transition from a large open pit into a novel “macroblock variant” block caving geometry at Chuquicamata mine, Codelco Chile’, Journal of Rock Mechanics and Geotechnical Engineering, vol. 11, pp. 549–561.
Flores, G & Karzulovic, A 2003, Geotechnical guidelines for a transition from open pit to underground mining, International Caving Study ICS-II, Task 4.
Freeport-McMoran, 2020, Indonesia Grasberg, viewed 30 January 2020,
Henning, JG 2016, ‘Stability and access implications of open pit mining through old underground mine’, Proceedings of the 3rd International Symposium on Mine Safety Science and Engineering, McGill University, Montreal, pp. 165–169.
Hoek, E 1994, ‘Strength of rock and rock masses’, ISRM News Journal, vol. 2, no. 2, pp. 4–16.
Jakubec, J, Woodward, R, Boggis, B, Clark, L & Lewis, P 2016, ,Underground mining at Ekati and Diavik diamond mines’, Proceedings of the 11th International Kimberlite Conference, Lucara Diamon, Vancouver.
Kauppila, P, Räisänen, ML & Myllyoja, S 2011, Best Environmental practices in metal ore mining, Finnish Environment,
KCGM 2020, Voids: An ever present hazard, viewed 30 January 2020,
Laubscher, DH 1990, ‘A Geomechanics classification system for the rating of rock mass in mine design’, Journal of South African Institute of Mining & Metallurgy, vol. 90, no. 10, pp. 257–273.
Leichliter, S & Larson, D 2013, ‘Geometallurgy for two recovery process operations: At Cripple Creek & Victor gold mine’, Mining Engineering, vol. 65, pp. 29–33.
McLeod, A 1992, ‘Mineral heritage oration, Arnold Black and hydraulic fill’, Proceedings of the Australasian Institute of Mining and Metallurgy Annual Conference, Australasian Institute of Mining and Metallurgy, Carlton, pp. 17–21.
Rose, ND & Hungr, O 2007, ‘Forecasting potential rock slope failure in open pit mines using the inverse-velocity method’, International Journal of Rock Mechanics & Mining Sciences, vol. 44, pp. 308–320.
Sharon, R & Eberhardt, E 2020, Guidelines for Open Pit Slope Monitoring, CRC Press, Boca Raton, in press.
Ulusay, R & Hudson, JA 2007, The Complete ISRM Suggested Methods for Rock Characterization, Testing and Monitoring: 1974-2006, ISRM Turkish National Group, Ankara.
Ulusay, R & Hudson, JA 2016, The Complete ISRM Suggested Methods for Rock Characterization, Testing and Monitoring: 2007-2014, Springer, London.
Whittle, D, Brazil, M, Grossman, PA, Rubinstein, JH & Thomas, DA 2015, Determining the open pit to underground transition: A new method, The University of Melbourne, Parkville.

© Copyright 2020, Australian Centre for Geomechanics (ACG), The University of Western Australia. All rights reserved.
Please direct any queries or error reports to