Campbell, R, Banda, H, Fajar, J & Brannon, C 2018, 'Optimising for success at the Grasberg Block Cave', in Y Potvin & J Jakubec (eds), Caving 2018: Proceedings of the Fourth International Symposium on Block and Sublevel Caving
, Australian Centre for Geomechanics, Perth, pp. 3-16, https://doi.org/10.36487/ACG_rep/1815_0.1_Campbell
At PT Freeport Indonesia’s Grasberg mining complex, the Grasberg open pit is scheduled to cease production in early 2019. Mining of the Grasberg deposit will then transition to the underlying Grasberg Block Cave (GBC) mine, with initial undercutting currently planned for late 2018. The GBC is projected to become the district’s flagship underground mine for the next two decades.
Early-stage production areas at the GBC are hosted within a heterogeneous rock mass. The footprint will be subjected to variable abutment and cave loading conditions. Mine design and sequencing adjustments, combined with customised ground support options, continually evolve to improve footprint reliability and permit a favourable transition between open pit and underground operations. This paper provides a snapshot of strategies employed to promote the successful caving operation at the GBC mine.
Keywords: caving, sequencing, ground support
Beck Engineering 2017, GBC Cave Simulation, report submitted to PT Freeport Indonesia, Beck Engineering, Sydney.
Call & Nicholas, Inc. 2008, GBC Geotechnical Feasibility Study, report prepared for PT Freeport Indonesia, Call & Nichols, Inc., Tucson.
Golder Associates 2016, 3D Numerical Stress Modelling and Ground Support Assessments of Extraction Level Excavations in the “Weak” Zones of Production Block 1 at the GBC, report submitted to PT Freeport Indonesia, Golder Associates.
Golder Associates 2018, Panel 26 Liner Design, report submitted to PT Freeport Indonesia, Golder Associates.
Leys, CA, Cloos, M, New, B & MacDonald, GD 2012, ‘Copper-gold-molybdenum deposits of the Ertsberg-Grasberg District, Papua, Indonesia’, in JW Hedenquist, M Harris & F Camus (eds), Geology and Genesis of Major Copper Deposits and Districts of the World: A Tribute to Richard H. Sillitoe, Special Publication 16, Society of Economic Geologists Inc., Littleton, pp. 215–235.
Mining Measurement Services 2010, GBC Mining Area: Rock Stress Measurements, report issued to PT Freeport Indonesia, Mining Measurement Services, Macclesfield.
Pascoe, ND, Mead, B & Vega, H 2016, ‘Grasberg Block Cave haulage project – design and construction update’, Proceedings of MassMin 2016, The Australasian Institute of Mining and Metallurgy, Melbourne, pp. 585–598.
PTFI 2016, Rock Mass Characterization for GBC PB1, internal PT Freeport Indonesia report, PT Freeport Indonesia.
Ratnaningrum, A, Yudanto, W, Wilson, AD, Purwanto, H & Litterbach, J 2012, ‘In situ stress measurement and interpretation at the Grasberg Block Cave mine, PT Freeport Indonesia’, Proceedings of MassMin 2012, The Australasian Institute of Mining and Metallurgy, Melbourne.