South32 has designated Hermosa its first next-generation mine, structured from the outset around automation and a net-zero carbon emissions operating model
Decision Focus
On July 7, 2026, the U.S. Forest Service concluded its environmental review and approved South32’s Hermosa Critical Minerals Project in southern Arizona’s Patagonia Mountains, roughly 50 miles south of Tucson. The permit clears a $2.16 billion operation to mine zinc, manganese, and silver from two structurally distinct deposits: the Taylor sulphide body carrying zinc, lead, and silver, and the Clark oxide body carrying zinc, manganese, and silver. For Mining Operations Directors tracking domestic supply chains, autonomous mine design benchmarks, and the regulatory trajectory for critical mineral projects, this approval is the signal worth watching.
90-Second Brief
As the week closes, the Forest Service granted approval under the FAST-41 permitting track, completing the process in two years. Hermosa sits on one of the world’s largest undeveloped zinc resources and targets battery-grade manganese for the North American electric vehicle supply chain alongside zinc and silver. South32 has designated Hermosa its first next-generation mine, structured from the outset around automation and a net-zero carbon emissions operating model. Together, the permitting timeline and the project’s design architecture set a new reference point for what regulators and developers expect from a greenfield critical mineral operation in the United States.
What Is Really Happening?
This approval is not simply one project clearing a regulatory gate. It reflects a deliberate federal repositioning on domestic critical mineral development, driven by national security and supply chain concerns tied to dependence on foreign sources, particularly China. The FAST-41 pathway compressed what has historically been a multi-decade permitting ordeal into a two-year cycle, and the National Association of Manufacturers publicly named that speed as the model for future projects.
Beneath the policy framing is an operational architecture question of greater consequence to mine directors. Hermosa carries two chemically distinct deposit types under one project boundary. The Taylor sulphide requires conventional flotation-based processing; the Clark oxide carries manganese, which demands a separate metallurgical pathway to achieve battery-grade product specification. Managing two processing routes—each with different reagent regimes, recovery mechanics, and product quality standards—within a single mine footprint is not a standard integration challenge. South32’s decision to absorb that complexity rather than stage the deposits independently signals confidence in processing technology maturity and in the long-term demand for battery-grade manganese from North American EV manufacturers.
The automation and net-zero framing is equally deliberate. South32 is not retrofitting an existing operation; Hermosa is being designed from first principles around those targets. That design choice has direct implications for how the mine’s mobile fleet, ventilation, power infrastructure, and remote operating architecture will be specified—and it becomes a reference point competitors and regulators will cite when evaluating what a modern mine permit application should include.
Why It Matters for Mining Operations Directors
Three operational implications deserve attention at the director level.
First, the processing complexity at Hermosa will drive demand for metallurgists, processing engineers, and maintenance technicians with dual-circuit experience—sulphide flotation and hydrometallurgical or oxide processing expertise within the same operation. The project anticipates up to 900 direct jobs, with thousands more indirect roles. In Arizona’s southern corridor, that workforce draw competes with existing copper and precious metal operations for the same skilled technical labor pool. Directors running operations in the southwestern U.S. or similar remote jurisdictions should anticipate tightening on specialized processing roles before Hermosa reaches full production.
Second, the FAST-41 precedent matters for any director whose operation is awaiting federal environmental review or planning a brownfield expansion that crosses federal land boundaries. The two-year cycle at Hermosa will be cited by industry groups as the benchmark, creating pressure on regulators to replicate that timeline and establishing an expectation in corporate planning that federal permitting is no longer the decade-long constraint it has historically been—which may accelerate capital allocation toward U.S.-based projects.
Third, the explicit automation and net-zero design standard embedded in Hermosa’s approval will likely influence future permit conditions on comparable projects. If federal agencies begin treating automation capability and decarbonization pathways as standard components of an acceptable project design rather than optional enhancements, directors building the business case for capital replacement cycles, fleet upgrades, or new project scoping will need those elements framed as permit-relevant commitments, not merely sustainability reporting items.
Forward View
Three fronts warrant active monitoring as Hermosa moves from permit to construction.
The battery-grade manganese processing circuit is the least proven element at scale in a North American context. South32’s pilot and feasibility results on the Clark oxide flowsheet deserve close attention. If the manganese circuit underperforms on grade or recovery, the EV supply chain rationale weakens and project economics shift toward zinc and silver alone—restructuring the capital case and potentially the operating tempo.
The FAST-41 pipeline is growing. Several other domestic critical mineral projects are positioned to use the same permitting pathway. If multiple large-scale operations move toward construction simultaneously across copper, lithium, and zinc sectors, competition for skilled workforce, specialized equipment, and engineering capacity will intensify well before any single project reaches full production.
South32’s presence at both Hermosa in Arizona and the Ambler Mining District in northwestern Alaska creates dual-jurisdiction exposure to federal land management decisions. Changes in federal land access policy, Indigenous consultation requirements, or environmental threshold standards in either region could affect project sequencing and capital deployment timelines.
What Is Still Uncertain
The confirmed permit covers the environmental review conclusion. Construction start timing, financing structure, and the sequence in which South32 develops Taylor versus Clark have not been publicly confirmed. The net-zero operating model is a stated design target, not a demonstrated operating outcome—no operational data exists because the mine has not been built.
The battery-grade manganese output claim rests on deposit potential, not on a confirmed processing route that has cleared commercial-scale validation. That distinction matters when evaluating supply chain commitments from downstream EV manufacturers or battery producers.
Workforce projections of up to 900 direct roles are project-level estimates without confirmed phasing or timing tied to construction milestones.
One Question for Your Team
Does your current capital project scoping include an explicit automation architecture and decarbonization pathway that would meet the design standard South32 is building into Hermosa—and if not, is that a gap in your permit strategy or only in your sustainability reporting?
Sources
- Ntd — Forest Service Approves Hermosa Critical Minerals Project in Southern Arizona (Link)
