Modern Mining January 2018

TIN

evaluating the offerings from various suppliers. At this stage, it is envisaged that a fleet of four trucks will be needed. The ore delivered to surface will be treated using conventional – and simple – gravity sepa- ration methods. Mined ore will be crushed to 100 % passing 10 mm. The coarse material (10 mm to +1 mm) accounts for 75 % of the mass flow and the tin contained in this size fraction will be recovered in conventional jigs. The fine material (-1 mm) makes up the bal- ance of the material and the tin contained in this stream will be recovered using spirals. The concentrates from both the jigs and spirals will be milled and subjected to flotation to remove sulphide material. The tin-rich concentrate – certified as conflict-free – will be thickened, filtered and dispatched by road to Goma, where it will be delivered to metal traders who will then take over the responsibility for the product and its onward transport to smelters. According to Faber, the plan is for the concentrate to be trucked down to Alphamin’s logistical ‘hub’ at Logu, just off the Goma-Kisangani road (and 38 km from the mine), using 8x8 rough-terrain trucks. At Logu, the product will then be trans- ferred on to normal road trucks for the balance of the journey to Goma. “We have designed and are trialling dual- purpose half-height containers to be used on the Bisie-Logu section of the route, the idea being to have the tin concentrates on the out- ward leg being balanced by diesel and supplies on the return leg,” Faber told Modern Mining . While on site recently, Modern Mining was able to view the progress being made on the project. The boxcut required to establish the portal was complete and the main drive to reach the orebody had advanced about 40 m, with the rate of advance temporarily slowed due to the need to install steel-arch sets for support over the first 50 m of the excavation. In addition, work was all but complete on a ventilation adit above the main drive with work soon to start on a 40-m deep, 3-m diameter, concrete-lined vertical shaft which will also serve as a second means of egress from the mine. Since Modern Mining ’s visit, the main drive has progressed well and by mid-December 100 m of advance had been completed. Progress is also being made on surface with earthworks now underway to create the terraces for the crushers and the process plant and a landing strip to serve the mine also being constructed. Most of the main contracts for the construc- tion of the mine and plant have now been awarded, with DRA appointed as the EPCM

contractor, Reliant as the mining contractor and Group Five as the SMPP contractor. Kongo River (an associate company of South Africa’s Teichmann Group), which was responsible for getting the boxcut completed on time and within budget, continues to be involved with the project and is now handling the civils for the processing plant, the balance of the earth- works, the airstrip and further work on the access road. All the contractors appointed thus far are either based in the DRC or have DRC experi- ence, with many of the DRA team, for example, having worked on the Kibali gold project, located just ‘up the road’ from Bisie. The only major contract remaining to be let is the Electrical and Instrumentation (E&I) contract. Once the contractors have finished their labours and the mine is commissioned next year, Alphamin will rank as one of the lynch- pins of North Kivu’s economy – and will certainly be the only commercial mine of any

Core shed at Bisie. Approximately 40 000 m of core drilling has been undertaken at the Bisie site.

substance in the province. But the new mine may be just the first of sev- eral. “Apart from further exploitation of Mpama North at depth, we see scope for a second min- ing operation at Mpama South, a few hundred metres down the ridge from Mpama North, and there are also other prom- ising targets throughout our licence area. We are sitting on an entire miner- alised system at Bisie and it is certainly not fanciful to see Mpama North as marking the emergence of an entire tin mining prov- ince,” concludes Kamstra. Photos, unless otherwise ac- knowledged, by Arthur Tassell

Bisie’s impressive metrics According to the Front-End Engineering Design (FEED) programme and associated Control Budget Estimate by DRA Projects, which gives the latest figures for the Mpama North project, ore will be delivered to the plant at a rate of 25 to 35 kt/month over an initial mine life of 150 months or 12,5 years. An overall tin recovery of 73 % is expected to be achieved by the process plant. The capex of the project is estimated at approximately US$151 million. A cash margin of some US$11 040 per tonne of tin sold is foreseen, yielding a LoM annual average EBITDA of approximately US$110 million (constant 2017 terms). The project has an NPV (8 %) of US$402,2 and an after-tax IRR of 49,1 % based on a tin price of US$21 400/t. The projected pay- back period is 17 months from the first tin production. 

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January 2018  MODERN MINING  47