JOHANNESBURG (miningweekly.com) - NYSE-listed gold and copper producer Newmont’s Tanami expansion project, in northern Australia, has reached commercial production, adding profitable production and extending the life-of-mine, the company stated Thursday.

The project, which was completed on time and within budget, will increase profitable gold production and support the ongoing exploration and development of Tanami’s prospective underground resource.

According to Newmont president and CEO Gary Goldberg, the expansion includes building a second decline in the underground mine and incremental capacity in the processing plant.

Tanami’s team has more than doubled gold production while cutting costs by about two-thirds and significantly improving resource confidence since 2012. The expansion project continues this trajectory, offering robust returns of 35% at a gold price of $1 200/oz. The team also delivered this project safely and on schedule, despite a one-month delay caused by record rainfall in the first quarter.

Goldberg added that the expansion project achieved commercial production for the approved $120-million development capital investment. It is expected to increase Tanami’s yearly gold production by 80 000 oz/y to between 425 000 oz/y and 475 000 oz/y of gold, lower all-in sustaining costs to between $700/oz and $750/oz, and extend mine life by three years.

“This expansion also creates a platform for further growth and studies to develop a second expansion,” he said.

The second decline was completed in mid-2016, enabling a step-change in mining rates – which ramp up to 2.6-million tons a year – and opening new avenues for exploration drilling. Since that time, Tanami’s team has improved mine ventilation to support further growth, and increased mine development rates through drilling efficiency gains.

The processing plant expansion included adding a ball mill, as well as a thickener and gravity circuit to improve recoveries and expand mill capacity from 2.3-million to 2.6-million tons a year. The mill reached commercial production by achieving sustained throughput, mill availability and grind size results in late August.

“Newmont has a strong track record for profitable project development. Over the past three years, we have built new mines at Merian, in Suriname, and Long Canyon, in the US, and delivered profitable expansions at Tanami and Cripple Creek & Victor, in the US.”

Newmont’s operations are primarily in the US, Australia, Ghana, Peru and Suriname.

“[Newmont] will complete an expansion at Northwest Exodus next year and, in 2017, announced three more expansion projects to improve profitability and extend mine life at Ahafo [in Ghana] and Twin Creeks [in Nevada],” Goldberg concluded.