Optimum Open Pit Design for Kenticha Tantalite Mine, Southern Ethiopia

The mining sector’s share in Ethiopia’s economy is gradually increasing. Among metallic mines, Legadembi for gold and Kenticha for tantalum are the main contributors. At Kenticha, the Ethiopian Mineral Development Share Company is producing tantalite concentrate of 40-60% grade by open pit mining. The mine area is comprised of the rocks of Neoproterozoic age, pegmatite, granite, serpentinite, and talc-chlorite schist. The ore-bearing pegmatite intruding the basement serpentinite, and talc schist rocks, is asymmetric, N-S trending, and locally affected by fractures and local faults. Mining, at present, is being done using conventional methods not by developing benches. An optimum open pit design is developed and its impact on the run of mine is evaluated based on the field data, technical mine report data, borehole data, tonnage data, grade data, and mine survey. The suggested design has taken into account the mine drainage, bench design, haul road design, and mine waste dump design. Also keeping in view the future mining and production requirements. The suggested open pit mine design can minimize the dilution and improve the ore recovery.