KALGOORLIE (miningweekly.com) – Global gold miner AngloGold Ashanti on Tuesday announced initiatives to cut costs at its Australian operations, while the miner was also hunting for project partners for its Obuasi project, in Ghana.

Speaking on the sidelines of the Diggers & Dealers conference, group planning and technical executive VP Graham Ehm said both the Sunrise Dam and Tropicana projects, in Australia, were considered key parts of the company’s portfolio.

The Tropicana operation was only in its second year of production and, already, the miner was looking at ways to improve the project’s performance while reducing costs.

“The focus now is on offsetting the gradual drop in grade by optimising the performance of the processing plant, as well as through exploration success, both in the tenements surrounding the mine and beneath the known ore zones,” Ehm said.

In keeping with that, AngloGold Ashanti has launched a parallel mining study at Tropicana to consider an alternative, low-cost approach to mining the down dip extensions of the Tropicana and Havana pits, along with extensions to the north and south.

“The mining study is looking at the application of mine design techniques that are used more commonly in mining other commodities, such as coal,” Ehm said, adding that the work was considering a starter pit followed by strip mining of a large cutback, which could be up to 400 m deep, and then backfilling the mined-out areas.

“This approach, which is aimed at extending mine life, would reduce stripping costs substantially with in-pit dumping and shorter haul distances. Peak cash flows are much lower compared with the traditional approach to a major pushback.”

At Sunrise Dam mine, AngloGold Ashanti last year concluded openpit mining and switched the project to a wholly underground operation. Since that time, the company has been working on increasing output at the mine from the original 1.4-million tonnes to an eventual 3.5-million tonnes.

“If you get the project to that scale, then the cost structure shifts and then Sunrise Dam gets its all-in costs down to below A$1 000/oz. Given the endowment at Sunrise Dam and its potential, it is still a prime part of our portfolio, but it needs work to get to where we want it to be,” Ehm said.

AngloGold Ashanti was also carrying out preliminary work on an underground crusher and conveyor system for haulage via a new decline to the north.

The project, if approved, would contribute to a reduction in long-term operating costs by reducing the underground trucking and ore handling costs. Ehm noted that prefeasibility level engineering design of the crusher and conveyor was in progress, and if the project went ahead, it would likely be commissioned by 2020.

Meanwhile, Ehm told journalists that the company was hoping to secure a development partner for its Obuasi project, in Ghana, as well as its projects in Columbia.

Operations at Obuasi were scaled back last year as the company moved to remedy legacy issues at the 180-year-old operation, and a feasibility study was currently under way into a future based on achieving higher production and lower costs through a scale-up of the underground mine and a rejuvenation of the plant and infrastructure.

Ehm noted that the project would likely require significant capital, which was why AngloGold Ashanti was hunting for a project partner of "substance".