The selection of the material sizing and mine dewatering systems are important elements in the development of a large-scale, high tonnage (greater than 4 Mt/a) underground hard rock mine._x000D_
The sizing system will influence the size and type of the ore haulage system and therefore how the underground project is developed. With more underground developments considering or implementing caving methods of mining, the selection of the material sizing systems is also influenced by the caving fragmentation._x000D_
Traditionally, crusher systems are used for material sizing in large hard rock mines, with the crusher installation and its ancillary equipment representing a substantial capital investment._x000D_
Underground cave mining type operations generally express themselves with large surface subsidence areas, which can lead to large inflows of water from major rain events or purging underground aquifer systems. To minimise disruption to mine production, the dewatering system needs to be sized, with consideration to both storage and pumping capacities. The balance between storage and pumping capacity is assessed to provide the optimal economic solution with the appropriate risk measures._x000D_
This paper outlines a process for the selection of material sizing and dewatering systems for large-scale caving operations. This process is illustrated with information drawn from Newcrest's Ridgeway Deeps Block Cave project. The Ridgeway Deeps Block Cave is located directly beneath the existing Ridgeway Sublevel Cave Mine._x000D_
FORMAL CITATION:Krek, R M, Leonforte, A, Pratt, A G L and Dunstan, G F, 2008._x000D_
Underground infrastructure requirements for underground cave mining operations, in Proceedings Tenth Underground Operators' Conference 2008, pp 205-218 (The Australasian Institute of Mining and Metallurgy: Melbourne).