Workers confer at African Barrick Gold’s Bulyanhulu gold mine in Tanzania. The company is planning to expand mine
output by an additional 150,000 oz/y by the end of 2015.

Bulyanhulu is a high-grade underground mine with reserves of 9.1 million oz at a grade of 9.5 g/mt gold and further resources of 6.2 million oz at 11.6 g/mt gold. A core element of African Barrick’s strategy for the mine is to bring production rates more into line with the scale of this resource base.

Three key projects will contribute to the production increase: improving mining practices in the existing mine to enable it to operate at reserve grade; commissioning of an expansion of the carbon-in-leach plant, now in progress; and acceleration of development to mine Bulyanhulu’s Upper East Zone.

The Upper East Zone is expected to 1.7 million oz of gold, averaging 60,000 oz/y over a life of more than 25 years.

The Upper East Zone is located on the eastern extension of the strike length of the mine, about 1.5 km east of the Bulyanhulu processing plant. The zone is currently included in Bulyanhulu reserves and was scheduled to be mined later in the mine’s life. Accelerated development of the area will require about $15 million of additional capital in 2014, with initial production now expected in July 2014.

The Upper East Zone was initially accessed in 2001 through a 1.8-km decline from the current mine’s ramping system, and this decline will provide access for initial mining in the zone. Mining will be performed by longhole stoping. The mine design minimizes up-front capital expenditure and ensures positive cash flow at current gold prices in each full year of production.

The zone’s two reefs will be mined simultaneously, using the existing underground access during the first four years of production. A box cut will then be developed to provide additional access.

The planned box cut is expected to take two years to construct, beginning in 2017, and is expected to cost $16 million. A second decline will be driven from the box cut to access shallower reserves.

In conjunction with Upper East Zone development, African Barrick will undertake a $20 million plant expansion to increase Bulyanhulu plant capacity from 1.1 million metric tons per year (mt/y) to 1.3 million mt/y.