PERTH (miningweekly.com) – Gold miner AngloGold Ashanti will start a feasibility study into a second underground mine at its Tropicana operations, in Western Australia, in 2021.

Speaking at the Diggers & Dealers conference, in Kalgoorlie, AngloGold Ashanti senior VP for Australia Michael Erickson noted that the miner had recently decided to go ahead with the Havana Stage 3 cutback, after a trade-off study confirmed that the openpit cutback returns would be superior to an early underground strategy.

“The Havana cutback will generate a further 32-million tonnes of ore for 1.5-million ounces of gold, extending the mine life from 2027 to 2030, with commercial production from the expanded Havana pit scheduled to be achieved in late 2020,” Erickson said on Monday.

“The Havana pit will provide a stable production base to incorporate additional underground sources and further exploration success into the life-of-mine plan,” he said.

The Boston Shaker underground mine, at Tropicana, achieved commercial production in September last year, and the project is targeted to reach its full production rate of one-million tonnes a year by the December half of this year.

Boston Shaker is expected to contribute some 100 000 oz/y of production to Tropicana, Erickson said.

“Boston Shaker is only the first of what we anticipate will be several underground mines at Tropicana,” he added.

Production at Tropicana is expected at between 400 000 oz and 450 000 oz this year, and from 2022 onwards, annual gold production will normalize at between 450 000 oz/y to 500 000 oz/y as the low grade stockpile ore in the mill feed is displaced by a larger proportion of Boston Shaker underground ore and an increasing contribution of higher grade ore from the Havana pit, as the cutback progresses.

Gold miner Regis Resources recently completed a A$903-million acquisition of a 30% interest in the Tropicana project, from fellow-listed Independence Group.

The two companies struck a sales agreement in April of this year, after IGO completed a strategic review of the asset, considering a number of options to realise full value for its share in the gold joint venture.

Following the necessary adjustments, the consideration paid to IGO amounted to A$889-million.