Gunnison Releases PEA for Arizona Copper Project, Plans for Open-pit, Heap-leach Operation

Gunnison Copper (TSX:GCU,OTCQB:EXMGF) is shifting its development strategy for the Gunnison copper project in Arizona, US, laying out plans for a conventional open-pit and heap-leach operation.

In a preliminary economic assessment (PEA), released on Thursday (November 14), the company explains that it is targeting the production of finished copper cathode for domestic consumption.

The PEA outlines an after-tax net present value of US$1.3 billion at an 8 percent discount, and an internal rate of return of 20.9 percent based on a long-term copper price of US$4.10 per pound.

Over its entire planned 18 year mine life, Gunnison is expected to produce 2,712 million pounds of copper cathode at an average cash cost of US$1.42 per pound and a sustaining cash cost of US$1.94 per pound. The estimated initial capital cost for the operation is US$1.3 billion, with an after-tax payback period of 4.1 years.

The company plans to develop the site as a vertically integrated operation, focusing on cost efficiency and environmental management. The PEA further states that the open-pit design will eliminate the need for tailings storage and will use less water per pound of copper compared to traditional concentrate production methods.

Gunnison will integrate an on-site sulfuric acid plant, generating 27 megawatts of clean energy.

Originally designed as an in-situ recovery (ISR) project, the decision to shift stems from advancements in sulfide leaching technologies and the potential for higher copper extraction rates through heap leaching.

The company retains the option to revert to an ISR operation if future circumstances warrant.

The Gunnison project is projected to contribute significantly to the local economy, with over US$840 million in taxes paid to federal, state and local governments, in addition to the creation of more than 650 local jobs.

Partnerships with community institutions are planned to provide training and support to local residents.

Based on the PEA results, Gunnison has been recommended to complete a prefeasibility study (PFS) for the open-pit project. This process is expected to take 18 months. Further drilling for mine planning purposes is also recommended, as are updates to the design of the acid plant. The company has also been advised to plan for infrastructure developments, including the addition of a rail spur to the Union Pacific Railroad and the relocation of Interstate 10.

The company has allocated a budget for these activities as part of its roadmap forward.

Gunnison, which recently changed its name from Excelsior Mining, emphasized the project’s role in supporting the US copper supply chain and highlighted its economic and operational feasibility.

In addition to the Gunnison project, the company also holds the past-producing Johnson Camp mine and additional exploration sites in Cochise County, Arizona. The Johnson Camp mine, in partnership with Nuton, a venture from major miner Rio Tinto (ASX:RIO,NYSE:RIO,LSE:RIO), is expected to resume production in 2025.

Securities Disclosure: I, Giann Liguid, hold no direct investment interest in any company mentioned in this article.