The Trump administration will formally sign off on South32 Ltd.’s Hermosa critical minerals project in Arizona on Tuesday, making it the first mining venture to win expedited permitting through the U.S. Department of Agriculture and ramping up Washington’s drive to onshore supply chains and cut reliance on China for key industrial metals.
The U.S. Forest Service is set to issue a record of decision greenlighting the mine near the U.S.-Mexico border, after the project was placed on the FAST-41 accelerated review list by the Federal Permitting Improvement Steering Council. Final approval lands two months ahead of the statutory deadline under federal environmental law, marking a high-profile milestone in U.S. efforts to streamline mining regulation.
Nominated for fast-track status during the Biden administration and finalized under Donald Trump’s second term, the project reflects broad bipartisan consensus on shoring up domestic critical mineral supplies.
Fully owned by Australian miner South32, the Hermosa complex hosts multiple ore bodies anchored by the Taylor zinc-lead-silver deposit — one of the world’s largest undeveloped zinc resources. Under JORC-compliant reserve figures, Taylor holds 65 million tonnes of ore grading 4.35% zinc, 4.90% lead and 82 grams per tonne of silver.
Serviced by an underground concentrator processing 4.3 million tonnes annually, the mine is forecast to yield 123,000 tonnes of zinc, 155,000 tonnes of lead and 8.2 million ounces of silver per year at steady state. It carries an initial 33-year mine life, with significant upside for extension as mineralization remains open in multiple directions.
Beyond its core zinc and lead assets, Hermosa includes the Peake copper deposit and the Clark battery-grade manganese deposit, covering five federally designated critical minerals: zinc, lead, silver, copper and manganese. These metals underpin steelmaking, large-format battery manufacturing, advanced electronics and national infrastructure.
Critically, the U.S. currently has no domestic primary manganese production, meaning the Clark deposit will directly fill a longstanding gap in the nation’s industrial and clean energy supply chains.
Hermosa will use a fully underground extraction model, limiting surface disturbance to roughly 750 acres — a fraction of the footprint of conventional open-pit operations. The project deploys dry-stack tailings technology and a water recycling circuit with 90% reuse efficiency to reduce aquifer strain, alongside electrified, remotely controlled mining equipment and a 17-mile dedicated power line, positioning it as a next-generation low-impact U.S. mine.
Surging construction costs, U.S. tariff policies, greater-than-expected shaft-sinking challenges and contractor productivity headwinds have lifted total capital expenditure from an initial $2.16 billion to around $3.3 billion. First concentrate production, originally targeted for H1 2027, has been pushed back to the first half of 2028, with full design capacity expected in June 2031.
South32 has committed to prioritizing North American smelters for copper produced at the site. The move comes as China dominates global zinc smelting capacity, leaving the U.S. heavily dependent on imported processed metal. Hermosa represents a direct push to extend U.S. zinc supply chains upstream into domestic primary production.
“The Hermosa Critical Minerals Project shows how increasing domestic production can reduce our dependence on vulnerable foreign sources, and power modern industries, advanced technologies, and essential infrastructure,” U.S. Secretary of Agriculture Brooke Rollins said in a statement.
Industry analysts frame the approval as a landmark for U.S. critical mineral strategy. Paired with the Trump administration’s broader slate of supply chain policies, the project is set to deepen the geopolitical dimension of base metals such as zinc and manganese, reinforcing a global shift toward regionalized, domestically secured mineral supply networks.
