Newmont Mining has started commercial production from the Subika Underground project, a new gold mine developed with an investment of around $186m at the Ahafo operations in Ghana.

Subika mine

Image: Ventilation fans at Subika Underground project in Ghana. Photo: courtesy of Business Wire.

The Subika Underground project has been taken up by the US-based mining company to add higher-grade, lower-cost gold production at the Ahafo mine located in the Brong Ahafo region in the western part of the African country.

The Ahafo mine has been in production since 2006 and had achieved production of five million ounces of gold in October 2016.

According to Newmont Mining, the Subika Underground project will have an average annual gold production of 150,000-200,000 ounces per year for the first years. The initial mine life of the underground gold mine has been estimated to be about 10 years.

The Subika Underground project comprises semi-autonomous loading operations, personnel tracking, proximity detection for vehicles along with a planned installation of ventilation-on-demand systems.

Newmont Mining CEO Gary Goldberg said: “In addition to increasing gold production and lowering costs at Ahafo, Subika Underground leverages the operation’s existing infrastructure and experienced workforce to further extend mine life.

“The mine provides an underground platform to explore additional upside potential in adjacent ore bodies and also includes some of the latest fit-for-purpose technologies to enhance safety, productivity and efficiency.”

The Subika Underground project, which was delivered on schedule and within budget, marks the third profitable expansion for Newmont Mining this year and the company’s tenth completed project since 2013.

Newmont Mining expects the average annual all-in sustaining costs (AISC) of the Ahafo mine to be improved by $250-350 per ounce compared to 2016 once the Ahafo Mill Expansion is also completed, which is expected to occur in the second half of 2019.

The Ahafo Mill Expansion project is anticipated to boost the annual mill capacity by 50% to about 10 million tonnes through the addition of a crusher, grinding mill and leach tanks to the circuit.

Further, the mill expansion, which will see an investment of $300-380m, is likely to boost margins and support profitable production at the Ahafo mine up to at least 2029, said Newmont Mining.