B2Gold Starts Construction of Otjikoto Gold Project
The Otjikoto feasibility study describes a project that has an initial mine life of 12 years based on probable a mineral reserve of 29.4 million mt at a grade of 1.42 g/mt gold containing 1.34 million oz of gold. Average annual gold production for years one to five is estimated at 141,000 oz/y at an operating cash cost of $524/oz; average life-of-mine gold production is estimated at 112,000 oz/y at an operating cash cost of $689/oz.
Pre-production capital cost is estimated at $244.2 million. Based on current pro-jections, the project would begin produc-tion in late 2014.
Run-of-mine ore from the Otjikoto open-pit will be delivered by 100-mt trucks to a primary crushing plant consisting of a gyrato-ry crusher and conveyor system that will feed a coarse ore stockpile. Stock-piled material will be reclaimed and treated through a SAG mill/secondary ball mill grinding circuit.
The ball mill discharge stream will be treated in a gravity concentration circuit for recovery of coarse gold. The gravity con-centrate will be processed in an intensive leach circuit.
The gravity tailings product will be thickened to 45% solids and treated in a cyanide leach circuit. The leach product stream will be pumped to a carbon-in-pulp (CIP) circuit for recovery of gold in solution. Gold will be recovered from the loaded car-bon in a split AARL [Anglo American Research Laboratories] elution circuit.
Gold solutions from the gravity intensive leach circuit and elution circuit will be treat-ed by an electrowinning process followed by smelting to produce doré bars.
The tailings stream from the CIP circuit will be treated in a cyanide destruction circuit using the SO2/Air process, before being pumped to a lined tailing storage facility.
The Otjikoto plant and support infra-structure will be built to support a plant expansion from the initial processing capac-ity of 2.5 million mt/y to 3 million mt/y with minimal additional capital expenditure.
An aggressive exploration drilling pro-gram continues on the high-grade Wolfshag zone discovered in late 2012 adjacent to the planned Otjikoto pit.