Hermosa Critical Minerals Project
The proposed underground mine project would continue the historic production of minerals within the Patagonia Mountains. The primary minerals targeted by the proponent, South32, are manganese and zinc, identified by USGS as critical minerals.
Location Summary
Patagonia Mountains - Huachuca Ecosystem Management Area - Sierra Vista Ranger District - Santa Cruz County - Arizona
District: Sierra Vista Ranger District
Project Milestones
| Milestone | Date |
|---|---|
| NOI in Federal Register | 05/10/2024 |
| DEIS NOA in Federal Register | 05/2025 (Estimated) |
| FEIS NOA in Federal Register | 02/2026 (Estimated) |
| Objection Period Start | 02/2026 (Estimated) |
| Decision | 07/2026 (Estimated) |
| Implementation | 09/2026 (Estimated) |
Project Documents
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