The feasibility study for the Taylor deposit, part of South32’s Hermosa project in Arizona, USA, has lived up to the mining company’s expectations, with final investment approval to develop this resource granted to the tune of $2.16 billion.
Hermosa was the first mining project added to the US Government’s FAST-41 process and is currently the only advanced project in the USA, which could supply two federally designated critical minerals, according to South32.
It is a project that is also set to apply ‘next generation mine’ design principles using automation and technology to drive efficiencies and lower operational greenhouse gas emissions. This includes a plan to incorporate battery-electric LHDs, drilling and ancillary fleets. This strategy, included in the feasibility study, results in improved efficiency, reduced diesel consumption and greenhouse emissions compared with the prefeasibility study on the project.
As well as this, the company plans to develop an integrated remote operations centre (iROC) in Santa Cruz County. The iROC will monitor and control mining, processing, maintenance and engineering to ensure the integration of activities and to optimise the entire value chain. Dry-stack tailings are also included in this development plan.
The feasibilty study highlighted a circa-4.3 Mt/y operation with average payable zinc-equivalent output of circa-253,000 t/y over a 28-year mine life. First production could occur in South32’s 2027 financial year.
The mine design for Taylor is a dual shaft underground mine, employing longhole open stoping with paste backfill. The mine development schedule has been aligned to a federal permitting process under FAST-41, which enables earlier access to multiple mining areas and an efficient ramp up to nameplate processing capacity of 4.3 Mt/y, it says. Shaft sinking is on-track to commence in the first quarter of South32’s 2025 financial year.
South32 Chief Executive Officer, Graham Kerr, said: “Final investment approval to develop Taylor is a major milestone aligned with our strategy to reshape our portfolio toward commodities that are critical for a low-carbon future.
“Taylor is expected to deliver attractive returns over multiple decades, with the feasibility study confirming the potential for a long-life, low-cost, low-carbon operation, with an initial operating life of circa-28 years, an average EBITDA margin of circa-50% and an internal rate of return of circa-12%.”
Kerr added: “As the first phase of a regional scale opportunity at Hermosa, Taylor’s infrastructure including dewatering, power, roads and site facilities, will unlock value for future growth options. These include Clark, our battery-grade manganese deposit, and potential discoveries in our highly prospective regional land package, which has already returned high-grade copper and zinc results from Peake and Flux.”