The results of a feasibility study on McEwen Copper Inc’s 100%-owned Los Azules copper project in San Juan, Argentina, have highlighted the potential application of a number of new and emerging technologies at the open-pit project, including the use of Nuton® leaching, trolley assist haulage, in-pit crushing and conveying, and battery-electric mine and services vehicles.
The study, McEwen Copper says, confirms Los Azules as a long-life, low-cost producer of high-purity copper cathodes with strong economic returns and sustainability. This is evidenced in a 21-year mine life with average annual copper cathode production of 148,200 t for an initial capital expenditure bill of $3.17 billion and post-tax internal rate of return of 19.8%.
McEwen said of the study: “The project design advances Los Azules toward construction readiness within a framework that reduces its environmental footprint. Project risk has been further reduced through a strategic collaboration agreement with IFC to potentially lead debt financing and additional funding proposals for infrastructure and construction.”
The environmental footprint statement is evidenced by a plan to use leaching, plus the solvent extraction-electrowinning process, to produce 99.99% copper cathodes (LME Grade A) on site without a smelter. The design also includes exclusively renewable power, an expectation of using 74% less water than conventional milling and no tailings dam.
This, the company says, results in a design that has a 72% lower mine-to-metal carbon intensity than the industry average mine-to-metal intensity, adding that the operation plans to achieve carbon-neutral status (Scopes 1 & 2) by 2038.
The company added: “With these results, Los Azules is positioned to become a supplier of responsibly produced copper, critical to the global energy transition towards a low-carbon sustainable future.”
One has to look into the opportunities section of the study to find out more about the potential use of new technology, with McEwen saying Nuton leaching technology (Rio Tinto venture) could allow processing of primary ores with the existing infrastructure (indicative recoveries >76%), while a conventional concentrator could also provide higher copper recoveries, plus recover gold and silver as well. “Either process could extend mine life by 30-plus years by economically treating primary sulphides,” the company said, clarifying that neither of these opportunities are included in the feasibility study base case.
McEwen said: “The project continues to develop electrification strategies for the mine and overall project including application of trolley assist for mine haulage, in-pit crushing and conveying and waste conveyance.”
It added that the timing for these applications and others is under final analysis, while it was “well positioned” to take advantage of emerging opportunities such as battery-electric mine and services vehicles, and longer-term developing technologies.
On the OEM front, meanwhile, McEwen says it has received preliminary finance proposals from Tier-1 OEMs such as Komatsu and Sandvik related to the potential support of $1.1 billion-plus in equipment and infrastructure financing. These were just two of a number of companies mentioned.
The feasibility study also outlined a construction start of 2026, SX-EW plant start-up in 2029 and first copper in 2030.
