Mashamba open pit mine is located 10 km southeast of Kolwezi town, in one of the richest copper areas of the Democratic Republic of Congo. The copper deposit block model has been run through mine optimization and provided a life of mine (LOM) of 6 years within four major pushbacks. The optimization process involved the use of NPV scheduler Datamine software (Lersch-Grossman algorithm). The ultimate pit and pushback designs have been executed using Minesight software. The haulage analysis has been conducted for the entire LOM of the deposit using the Minesight Haulage tool. Initial simulation of truck fleet size was done assuming a truck availability of 85%. However, it has since been observed that in practice, 85% availability over the entire life of the mine will be an unrealistic target it was therefore interesting to conduct a set of scenarios using the Minesight haulage tool to vary the availability and to compare the fleet size variation. In this paper, curve-fitting techniques have been used to observe, analyse, and establish a mathematical relationship to correlate dump truck availability and fleet size data, and to determine how strongly the two variables are correlated. Despite the fact that the mathematical equation and correlation factor calculated in this case study are not expected to lead to a replacement of haulage software packages, they were found to be helpful tools for quickly predicting the fleet size (number of trucks required for the entire mine life) based on a given set of truck availabilities at Mashamba open pit.

The Mashamba East open pit mine is a copper-cobalt operation located in the Democratic Republic of Congo, in the mineral-rich Katanga Province 10 km southeast of Kolwezi town. Previously owned by Gecamines (a state-owned mining company), Mashamba East pit was recently separated from the neighbouring Mashamba West deposit, which now belongs to a Chinese company (Sicomines). The challenges in the mine optimization and the pushback approach will be to take into account the presence of a waste dump on the south of the deposit, the small distance between the pit and the property limits to the east and west of the deposit, and finally, the presence of a tailings storage facility to the north of the pit,. Running the input data through Datamine NPV Scheduler showed that it is possible to design operational pushbacks to produce a well-balanced schedule and mining sequence. Mashamba East pit is located in a confined area, and this paper outlines the approach taken to achieve a viable mining sequence, taking into account the abovementioned restrictions. NPV Scheduler software will be used to optimize and determine pushbacks, while Minesight software will be used to design the ultimate pit and the operational pushbacks.