Authors: Carter, TG; de Graaf, PJH; Dixon, J; Creighton, A; Macciotta, R; Silva-Tulla, F; Stacey, P

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Carter, TG, de Graaf, PJH, Dixon, J, Creighton, A, Macciotta, R, Silva-Tulla, F & Stacey, P 2022, 'Transitioning from mine operations to closure: the dilemma of differing geotechnical design acceptance criteria perspectives', in AB Fourie, M Tibbett & G Boggs (eds), Mine Closure 2022: Proceedings of the 15th International Conference on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 237-258,

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For open pit mining, understanding and managing slope performance is critical for both operations and closure. Towards the end of mine life, achieving reliability of slope performance in operations often necessitates real-time implementation of active slope stabilisation controls. This situation changes significantly towards closure, when production economics are no longer the priority, and resources for field monitoring control and active slope management diminish. The risk profile also shifts to a greater focus on stakeholder needs, including the environment and social acceptance, as land use changes. Although risk profiles will shift, the safety goal of ‘zero harm’ needs to continue to be achieved through all phases. Historically, most final pit slopes were not designed for closure. Rather, they tended to be optimised for production efficiency and thus were typically too steep for long-term reliability. The key question then becomes – what happens when the controls that have been put in place for maintaining their stability are decommissioned for closure? With sufficient understanding gained during operations, it may be possible to adequately forecast behaviour and define a Design Acceptance Criteria appropriate for the slope, for postclosure, once operational controls are decommissioned. This paper is hoped will help address this dichotomy and provides suggestions to meet industry objectives. It is also intended to promote discussion on this transition, such that industry and regulator perspectives can be accommodated alongside each other within the forthcoming Large Open Pit (LOP) Guidelines for Mine Closure handbook publication, currently in preparation under the auspices of the LOP initiative.

Keywords: design acceptance criteria, relative stability guideline, target stability reliability, geotechnical design, geotechnical risk, slope stability, as low as reasonably possible, post mining land use

Adams, BM 2015, ‘Slope stability acceptance criteria for opencast mine design’, in G Ramsey (ed.), Proceedings of the 12th Australia New Zealand Conference on Geomechanics, International Society for Soil Mechanics and Geotechnical Engineering, London.
Asia-Pacific Economic Cooperation 2018 Mine Closure Checklist for Governments, Asia-Pacific Economic Cooperation Mining Task Force, Canberra.
Australian Government 2016, Leading Practice Handbook: Mine Closure, Leading Practice Sustainable Development Program for the Mining Industry, Canberra.
Australian National Congress on Large Dams 2012, Guidelines on Tailings Dams – Planning, Design, Construction, Operation and Closure, Australian National Congress on Large Dams, Hobart.
Canadian Dam Association 2013, Dam Safety Guidelines 2007 (2013 edition), Canadian Dam Association, Ottawa.
Carter, TG 2014, ‘Guidelines for use of the scaled span method for surface crown pillar stability assessment’, in Proceedings of the 1st International Conference on Applied Empirical Design Methods in Mining, Lima-Perú.
Carter, TG 2019, ‘Retrospective Assessment of Structurally Controlled Crown Pillar Failures’, Proceedings of the 53rd North American Rock Mechanics/Geomechanics Symposium, Curran Associates, Inc., Red Hook.
Carter, TG & Barnett, WP 2021, ‘Improving reliability of structural domaining for engineering projects’, Rock Mechanics and Rock Engineering, vol. 55, pp, 2523–2549,
Carter TG & Miller, RI 1995, ‘Crown pillar risk assessment – planning aid for cost effective measures for mine closure remediation’, IMM Transactions (Section A), vol. 104, pp. A1–78.
Christian, JT & Urzúa, A 2009, ‘Reliability related to factor of safety and uncertainty’, International Foundation Congress and Equipment Expo, Orlando.
Cole, KW 1993, ‘Building over abandoned shallow mines – paper 1: considerations of risk and reliability’, Ground Engineering, vol. 26, no. 1, pp. 34–37.
de Graaf, PJH, Desjardins, M & Tsheko, P 2019, ‘Geotechnical risk management for open pit mine closure: a sub-arctic and semi-arid case study’, in AB Fourie & M Tibbett (eds), Mine Closure 2019: Proceedings of the 13th International Conference on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 211-234,
de Graaf, PJH, Beale, G, Carter, TG & Dixon, J 2021, ‘Geotechnical Guidelines for Open Pit Closure – a new publication by the Large Open Pit (LOP) project’, in AB Fourie, M Tibbett & A Sharkuu (eds), Mine Closure 2021: Proceedings of the 14th International Conference on Mine Closure, QMC Group, Ulaanbaatar,
Duncan, MJ 2000, ‘Factors of Safety and reliability in geotechnical engineering’, Journal of Geotechnical Engineering, vol. 126, no. 4, pp. 307–316.
Federal Government of the United States 1978, Uranium Mill Tailings Radiation Control Act, Public Law 1978, pp. 95−604.
Hadnutt, C 2020, Routine Maintenance or Major Repair? The Meaning of ‘Design Life’ Obligations,
Hawley, PM & Cunning, J 2017, Guidelines for Mine Waste Dump and Stockpile Design, CSIRO Publishing, Collingwood.
International Commission on Large Dams 1987, ‘Dam safety guidelines’, Bulletin 59, International Commission on Large Dams, Paris.
International Commission on Large Dams 2017, ‘Dam safety management: operational phase of the dam life cycle’, Bulletin 154, International Commission on Large Dams, Paris.
International Council on Mining & Metals 2019, Integrated Mine Closure: Good Practice Guide, 2nd edn, International Council on Mining & Metals, London.
Kirsten, HAD & Moss, ASE 1985, ‘Probability applied to slope design – case histories’, Proceedings of the ASCE Symposium on Rock Masses and Probability of Slope Failure, Denver, pp. 106–119.
Logsdon, M 2013, ‘What does ‘perpetual’ management and treatment mean? Toward a framework for determining an appropriate period-of-performance for management of reactive, sulfide-bearing mine wastes’, in Wolkersdorfer, Brown & Figueroa (eds), Reliable Mine Water Technology, IWWA, Golden.
Macciotta, R, Creighton, A & Martin, CD 2020, ‘Design acceptance criteria for operating open-pit slopes: an update’, CIM Journal, vol. 11, pp. 248–265.
Macciotta, R, Martin, C D, Morgenstern, NR & Cruden, DM 2016, ‘Development and application of a quantitative risk assessment to a very slow-moving rock slope and potential sudden acceleration’, Landslides, vol. 13, pp. 765–785.
McCracken, A & Jones, GA 1986, ‘Use of probabilistic stability analysis and cautious blast design for urban excavation’, Proceedings of Rock Engineering and Excavation in an Urban Environment Conference, IMM, London, pp. 231–240.
Miller, K 2019, ‘Constructing a legally sound demonstration of ALARP’, Proceedings of Hazards 29, Symposium Series No. 166, Institution of Chemical Engineers, Birmingham.
Oil Sands Tailings Dam Committee 2014, De-licensing of Oil Sands Tailings Dams, technical guidance document, Oil Sands Tailings Dam Committee.
Pine, RJ 1992, ‘Risk analysis design applications in mining’, Transactions of the Institution of Mining and Metallurgy, vol. 101, pp. A149–A157.
Pine, RJ & Roberds, WJ 2005, ‘A risk-based approach for the design of rock slopes subject to multiple failure modes—illustrated by a case study in Hong Kong’, International Journal of Rock Mechanics and Mining Sciences, vol. 42, pp. 261–275.
Priest, SD & Brown, ET 1983, ‘Probabilistic Stability Analysis of Variable Rock Slopes’, Transactions of the Institution of Mining and Metallurgy, vol. 92, pp. Al-12.
Read, J & Stacey, P 2009, Guidelines for Open Pit Slope Design, CSIRO Publishing, Collingwood.
Silva, F, Lambe, TW & Marr, WA 2008, ‘Probability and risk of slope failure’, Journal of Geotechnical and Geo-environmental Engineering, ASCE.

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