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

NOI in Federal Register05/10/2024
DEIS NOA in Federal Register05/01/2025 (Estimated)
FEIS NOA in Federal Register02/01/2026 (Estimated)
Objection Period Start02/01/2026 (Estimated)
Decision07/01/2026 (Estimated)
Implementation09/01/2026 (Estimated)

Project Documents

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