South32’s $3.3 billion Hermosa critical-minerals project has completed federal permitting, becoming the first U.S. mining project to move through the FAST-41 program from start to finish.
The U.S. Forest Service signed the final Mine Plan of Operations Sept. 2 at the site in the Patagonia Mountains, KTAR News reported. The approval authorizes infrastructure on Coronado National Forest land, including a primary access road, secondary dry-stack tailings facility and supporting operations. The federal Permitting Dashboard lists the review complete as of Sept. 2.
Hermosa entered FAST-41 in May 2023 during the Biden administration. The 2015 law coordinates agencies around public deadlines and reviews without waiving environmental statutes. The Trump administration later expanded the use of the process for domestic mining projects.
Federal officials described Hermosa as a national security project. It could produce up to five federally designated critical minerals, including zinc, silver and manganese. The United States has not mined manganese since the 1970s and currently relies entirely on imports. Project sponsors expect up to 900 direct jobs at peak operations, with average earnings projected at twice local levels.
Construction on private land is roughly halfway complete. South32 expects underground zinc mining in late 2027 and first processed zinc in the first half of 2028. Initial earthwork and surveys on federal land are expected within weeks.
Not everyone welcomed the approval. Democratic Rep. Adelita Grijalva of Arizona raised objections, saying the process left questions about groundwater, public health, wildlife and community and tribal input unresolved. The Patagonia Area Resource Alliance says it is weighing legal options. South32 says more than 135 environmental, conservation and monitoring requirements are federally enforceable.
The permit allows development to advance, but commercial manganese processing remains subject to a separate company investment decision.
