This paper is hosted with the kind permission of the Universidad de Chile, Eighth International Conference & Exhibition on Mass Mining, 2020.
Paredes, P, Popa, IL, Kline, PR & Sykes, MJ 2020, 'Undercutless caving at Newcrest: towards the next generation of cave mining', in R Castro, F Báez & K Suzuki (eds), MassMin 2020: Proceedings of the Eighth International Conference & Exhibition on Mass Mining
, University of Chile, Santiago, pp. 166-181, https://doi.org/10.36487/ACG_repo/2063_07
Mass mining and particularly the cave mining industry is facing technical challenges that include those associated with greater depths, lower grades and demand for increased productivity (Flores 2014). New orebodies and expansion of current mines demand safer, faster, and lower-cost approaches to establishment and operation. The rate at which a cave is established is crucially dependent on the efficiency of the undercut process, which is becoming increasingly difficult and costly to execute in deeper orebodies. For these reasons, the development of alternative and more effective cave establishment methodologies has become critical. In this context, Newcrest has initiated the NextGen Caving programme, which endeavours to develop and implement novel, cost effective techniques for mining the next generation of block caves aiming to unlock low grade massive ore bodies at greater depths. Among the NextGen initiatives is the Undercutless Caving concept or Single Pass Cave Establishment (SPCE). This aims to improve safety, and reduce cave establishment time and cost, by establishing the drawbell and undercut components of a traditional block cave method from a single level and process. If proven to be successful, Single Pass Cave Establishment will not only change how Newcrest evaluates and constructs block cave projects, it will also represent a step change for the caving industry. To engineer, test, validate and implement this concept, Newcrest has embarked on an ambitious project consisting of a design study and two trials. This paper introduces the Undercutless Caving concept alongside the results of the first practical trial at the Telfer Mine in Western Australia. Successful results from a practical trial at Telfer have been achieved, with complete undercut and connectivity gained across the major and minor apex pillars of the planned four drawbell layout, of comparable pillar sizes to that at Cadia East. As an industry first of achieving drawbell and undercut establishment from a single level with no void above and with unprecedented drawbell and pillar dimensions, this milestone represents a significant step forward in cave establishment for the industry.
Barraza, M & Crorkan, P 2000, ‘Esmeralda Mine Exploitation Project’, in G Chitombo (ed.), Proceedings of MassMin 2000, Australian Institute of Mining and Metallurgy, Melbourne, Australia, pp. 267-278.
Butcher, R 2000, ‘Block Cave Undercutting – Aims, Strategies, Methods and Management’, in G Chitombo (ed.), Proceedings of MassMin 2000, Australian Institute of Mining and Metallurgy, Melbourne, Australia, pp. 405-441.
Codelco 2018, ‘Evolution of Mining Methods at El Teniente Mine’, presentation for 2018 Caving Knowledge Workshop, Phoenix, USA.
Cuello, D & Newcombe, G 2018, ‘Key geotechnical knowledge and practical mine planning guidelines in deep, high-stress, hard rock conditions for block and panel cave mining’, in Y Potvin & J Jakubec (eds), Proceedings of the Fourth International Symposium on Block and Sublevel Caving, Australian Centre for Geomechanics, Perth, pp. 17-36
Dunstan, G and Popa, L 2012, ‘Innovative Cave Establishment Practices at Ridgeway Deeps’, Proceedings of MassMin 2012, Canadian Institute of Mining, Metallurgy and Petroleum, Sudbury, Canada.
Dunstan, G 2016, ‘The truth is stranger than fiction – the story of Ridgeway Gold Mine’, Proceedings of MassMin2016, Australasian Institute of Mining and Metallurgy, Sydney, pp. 19-30.
Flores, G 2019, ‘Major hazards associated with cave mining: are they manageable?’, in J Wesseloo (ed.), Proceedings of the First International Conference on Mining Geomechanical Risk, Australian Centre for Geomechanics, Perth, pp. 31-46.
Flores, G 2014, ‘Future challenges and why cave mining must change’, in R Castro (ed.), Proceedings of Caving 2014, third International Symposium on Block and Sublevel Caving, Universidad de Chile, Santiago, Chile, pp. 23-52.
Kilkenny, D, Kline, P & Nardini, K 2019 “Collaboration and Change Management, keys to successful automation implementation” Submitted for the 2020 AusIMM Underground Operators Conference.
Laubscher, D, Guest, A, Jakubec, J & Chitombo, G 2017, ‘Guidelines on Caving Mining Methods - the underlying concepts’. Chapter 8. W.H. Bryan Mining and Geology Research Centre, Brisbane, Australia, pp. 103 – 109.Macquarie Research
2016, ‘Metals and Mining. A chip off the new block GLOBAL. Evaluating the risks and rewards of the future block cave. Inside’, Macquarie Group. [21 November 2016].
Manca, L & Flores, G 2013, ‘Modern Planning Practices for Cave Mining’, Proceedings of MinePlanning 2013, 3rd International Seminar on Mine Planning, GECAMIN, Santiago, Chapter 3.
Pierola, M, Adamson, W & Diaz, M 2006, ‘Design, Implementation and Control of Large Scale Draw Bells (zanjas) in Panel Caving, Codelco Division El Teniente’. In proceedings of Fragblast-8. The 8th International Symposium on Rock Fragmentation by Blasting. Santiago, Chile, pp. 279 – 289.
Rojas, E, Molina, R, Bonani, A, & Constanzo, H 2000, ‘The pre-undercut caving method at the El Teniente Mine, Codelco – Chile’, in G Chitombo (ed.), Proceedings of MassMin 2000, Australian Institute of Mining and Metallurgy, Melbourne, Australia, pp. 261-266.
Tawadrous, A & Preece, D 2015, ‘A novel blasting technique to create drawbells and eliminate the undercut level in block cave mining’, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, The Australasian Institute of Mining and Metallurgy, Melbourne, Australia, pp 617–624.
Trueman, R, Pierce, M & Wattimena, R 2002, ‘Quantifying stresses and support requirements in the undercut and production level drifts of block and panel cave mines’, International Journal of Rock Mechanics and Mining Sciences, Vol. 39, pp. 617 – 632.
Vergara, C, Rivera, N & Music, A 2018, ‘Drilling and Blasting in El Teniente Mine – Design and Operational Practices- Teniente Sub 6 case study” II Ibero-American Congress in Underground Mining and Open Pit. Castro, R. and Herazo, Y. (eds). Santiago, Chile, 13-15 June 2018. Presentation, in Spanish.
Woods, MJ, Fitch, S, Doolan, J & Barnett, DS 2019, ‘A case study: managing decline deformation in an active sublevel caving operation’, in J Wesseloo (ed.), Proceedings of the First International Conference on Mining Geomechanical Risk, Australian Centre for Geomechanics, Perth, pp. 505-520