Modern Mining July 2019

COUNTRY FOCUS: BOTSWANA

and 21,9 g/t Ag. The deposit has a strike length of 4,2 km, an average width of approximately 9 m and remains open below 1 200 m. The Zone 5 ore will be processed in the Boseto concentrator, which was acquired by Cupric in 2015 when it paid around US$35 million to purchase the assets of Discovery’s Botswanan subsidiary, Discovery Copper Botswana. Included in the deal were not only the 3 Mt/a processing facility but also other infrastructure (including a genset-based power station, a township and a tailings storage facil- ity), as well as additional ore resources and targets. Cupric’s purchase of the processing plant (designed and built by Sedgman and less than eight years old) and the other assets has translated into major capex savings running to tens of millions of dollars. The Zone 5 mine will consist of three sepa- rate but adjacent and interlinked underground mines, each producing 1,2 Mt/a on average over the first five years of operation. Each of the mines will have its own independent ramp access and operate over a strike length of approximately 1 000 m, extracting ore using a conventional sub- level open stoping mining method, transitioning to paste backfill below 450 m. The Central and South mines will have twin declines and the North mine a single decline. Says Ferreira: “Our mine design is very innovative, particularly the twin decline con- cept, and allows for an increased number of stoping fronts per level from 2 to 4. We have parallel return air systems, which facilitate ven- tilation on demand, twin electrical networks, a centralised pumping system, and an orepass

will only mine sulphides and we therefore expect to achieve excellent recoveries – around 89 % Cu – in the processing plant. In addition, we have a well-understood, world-class ore- body at Zone 5 which lends itself to a highly mechanised, low-cost mining operation,” he says. He also notes that the authorities in Botswana – a country universally acknowl- edged as being one of Africa’s best mining jurisdictions – have been unstintingly support- ive of the project. The sediment-hosted, structurally con- trolled, stratiform Zone 5 deposit hosts a resource – defined by over 200 km of drilling – which totals 91,7 Mt at a grade of 2,13 % Cu

Work underway on the central boxcut with geocell installation in progress.

July 2019  MODERN MINING  31