The Sentinel Pit is being mined in a series of terraced phases, using large-scale mining equipment, and with mining costs expected to be minimised through the adoption of bulk mining and ore handling methods featuring electric shovels and drill rigs, trolley-assisted (TA) haulage, and in-pit primary crushing and conveying (IPCC). Waste and ore haul cycle times, and hence fuel consumption, are expected to be reduced through the adoption of TA and IPCC.
Open pit mining at Sentinel commenced in two surface box-cut areas of the Phase 1 Pit; ie, in the north west boxcut in April 2013, and then in the south boxcut from early 2014. Since 2013-2014, mining has proceeded in the Phase 1 pit to a current depth of approximately 200 m.
The Phase 2 pit, immediately to the east, was progressively cleared and grade control drilled from 2016. Mining from the southern pit crest limits, 800 m across to the Musangezhi River, now extends along a strike length of 1.2 km and to a depth of approximately 25 m.
Mining capacity will eventually increase to around 68 million bcm of ore and waste mined per annum. The ultimate 5.7 kilometres long, 1.5 kilometres wide and 390 metres deep pit is being mined in stages, with ore crushed in-pit and conveyed overland to the Sentinel process plant.
Four in-pit crushers and associated in-pit and overland ore conveyors have now been installed and are operational. The surface conveyors extend across to the plant crushed o ........
