South32’s Hermosa zinc-silver project in southern Arizona received its final federal Record of Decision in early July, completing the FAST-41 permitting process. The approval covers public-land infrastructure, including a high-voltage transmission line, a second access road, tailings facilities and water-discharge points. The mine itself had already received Arizona state approval, with construction on private land about halfway complete.
Hermosa hosts a major undeveloped zinc deposit, alongside a battery-grade manganese deposit and the emerging Peak copper discovery. Construction costs have risen above $2 billion amid inflation, materials, labour and contractor pressures, although South32 says most remaining work is now contracted. Both production shafts are expected to reach final depth before year-end; underground mining is scheduled for late 2027 and first production is targeted for early 2028. These remain planned milestones subject to project execution.
