Gunnison starts up SX-EW plant at Johnson Camp mine

Executive Summary

• Gunnison Copper’s Johnson Camp SX‑EW plant has been successfully started up and is on track for its first copper cathode sales in September 2025.
• All major construction elements—including the leach pad, on‑pad crushing circuit, agglomerator, processing equipment, and a new LNG system—are on schedule and fully commissioned.
• The project is fully financed by Nuton LLC (a Rio Tinto venture) and targets up to 25 million lb of copper cathode production annually once in full operation.

Key Details

• SX‑EW plant and electrowinning circuit are operational; first copper sales anticipated for Q3 2025.
• Leaching of run‑of‑mine material has commenced, with copper‑rich solution already being pumped to the SX plant.
• Final phase of leach pad construction is on schedule; on‑pad crushing circuit installed and commissioning underway.
• Agglomerator and processing equipment placed; final mechanical/electrical work in progress.
• New LNG system at EW plant fully commissioned and supporting electrowinning start‑up.
• Construction financing provided by Nuton LLC, a Rio Tinto venture.
• Production capacity of the Johnson Camp asset: up to 25 million lb (≈11,340 t) of copper cathode per year.
• Measured & indicated resource for the broader Gunnison project: 831.6 M t at 0.31% Cu (191.3 M t @ 0.37% measured; 640.2 M t @ 0.29% indicated).
• Preliminary Economic Assessment (PEA) highlights: NPV $1.3 bn (8% discount), IRR 20.9%, payback 4.1 years.

Notable Quotes

“With the start‑up of the SX‑EW plant ahead of schedule, we have achieved another major step towards our targeted copper cathode sales in September this year,” – Robert Winton, Senior Vice‑President of Operations.
“The dedicated team at Johnson Camp has executed this start‑up without incident and in record time, preparing for our first harvest of made‑in‑America copper to be sold in Q3 this year.” – Robert Winton.