The US Forest Service has released a final record of decision for diversified miner South32's Hermosa critical minerals project, in Arizona, completing the federal National Environmental Policy Act (Nepa) process needed for the project's ancillary infrastructure development on National Forest Service land after years of environmental study, public input and stakeholder consultation.

Located in the Patagonia Mountains, about 80 km south-east of Tucson, Arizona, Hermosa comprises the zinc/lead/silver Taylor sulphide deposit.

The Nepa process paves the way for South32 to fully develop the project beyond its privately held land, including building ancillary infrastructure such as a primary access road, a secondary dry-stack tailings facility, and allowing utility UniSource Energy Services to build a portion of an 138 kV power line on Coronado National Forest land.

Hermosa is an advanced mining project in Southern Arizona capable of producing up to five federally designated critical minerals, including zinc, silver and manganese.

Construction is already halfway complete on private land. It was the first mining project added to, and covered under, the federal FAST-41 permitting programme, a process reserved for infrastructure projects that must meet certain rigorous criteria to demonstrate how they will benefit the nation.

“From the beginning, we designed Hermosa to be a different kind of mine, and the federal review process helped make it even better,” says South32 Hermosa president Pat Risner.

He adds that years of agency review, Tribal consultation and community engagement strengthened environmental protections, informed project refinements and shaped a project that can transform the local economy.

"We are grateful to everyone who participated throughout the process and look forward to continuing that engagement as we move from construction and development into operations.”

The final record of decision also represents an important milestone in the broader national conversation around domestic critical mineral development and permitting reform.

Hermosa’s advancement under FAST-41 did not reduce the robustness of environmental review or limit public input. Rather, the process helped improve interagency coordination, transparency and accountability across federal agencies while ensuring the project moved through permitting in a timely and disciplined manner, Risner states.

South32's Hermosa project will not only be an economic driver for Santa Cruz County, but for the entire US, producing critical minerals that will power the twenty-first-century energy economy, says US Senator Ruben Gallego.

Hermosa marked the first project covered by FAST-41 and helped lay the groundwork for the 57 additional mining projects that have followed during the Trump administration.

South32 ultimately committed to more than 135 conservation, mitigation and monitoring measures, which were developed together with federal agencies, Tribes and other local stakeholders.

Hermosa is poised to create 900 jobs during peak operations and support investment across surrounding communities for decades to come, all within a surface footprint of 750 acres and with aims to use 90% less water than other mines in the region.