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ADEQ to revise air quality permit for proposed mine in Patagonia Mountains after EPA rejection

The project site for South32 Hermosa’s zinc-manganese mine in the Patagonia Mountains.
Gabriel Pietrorazio/KJZZ
The project site for South32 Hermosa’s zinc-manganese mine in the Patagonia Mountains.
Coverage of tribal natural resources is supported in part by Catena Foundation

An Australian-owned company has been preparing to open a new zinc and manganese mine in the Patagonia Mountains. A recent permit rejection by the EPA threatened to stall the project near the Arizona-Mexico border. Now, the state Department of Environmental Quality has agreed to make revisions.

South32 Hermosa was the nation’s first mining project named to the FAST-41 process — meant to streamline permitting for infrastructure projects. Since then, environmentalists sought to slow it down.

A group of conservation advocates — including the Arizona Mining Reform Coalition, Sierra Club Grand Canyon Chapter and Center for Biological Diversity — petitioned the EPA to review an air quality permit issued last August. The federal agency found that, in doing so, ADEQ failed to comply with the Clean Air Act.

Petitioners claim that, by not establishing enforceable pollution limits, the proposed mine in Santa Cruz County would be allowed to release hundreds of tons of particulate matter — lead, manganese and smog-forming nitrogen oxides — each year.

“That’s not the issue that was remanded back to ADEQ,” South32 Hermosa President Pat Risner told KJZZ. “The few conditions that have gone back for clarification are fairly minor, and ones, you know, they will need to turn around fairly quickly.”

Arizona now has 90 days to fix the permit or else the EPA assumes authority, and the state agency told KJZZ it “intends to respond to the order and revise the permit” within the allotted time frame.

Although the South32 Hermosa mining project has consulted with 14 neighboring tribes, Risner mentioned none of them have expressed any concern about potential emissions yet.

“But again, our engagement with tribes started six years ago,” added Risner, “with the intent to make sure we design the project to avoid impacts, understand their connections to the land and find opportunities to work together.”

More Tribal Natural Resources News

Gabriel Pietrorazio is a correspondent who reports on tribal natural resources for KJZZ.