# Clean Air Act Operating Permit Program; Order on Petition for Objection to State Operating Permit for the South32 Hermosa Project
**AGENCY:**
Environmental Protection Agency (EPA).
**ACTION:**
Notice of final order on petition.
**SUMMARY:**
The Environmental Protection Agency (EPA) Administrator signed an order dated May 30, 2025, granting in part and denying in part a petition dated September 13, 2024, from the Center for Biological Diversity, Patagonia Area Resource Alliance, Sierra Club, Arizona Mining Reform Coalition, Calabasas Alliance/La Alianza Calabasas, and Friends of the Santa Cruz River. The Petition requested that the EPA object to a Clean Air Act (CAA) title V operating permit issued by the Arizona Department of Environmental Quality (ADEQ) to South32 Hermosa Project (“Hermosa”) for its zinc, lead, manganese, and silver mine in Santa Cruz County, Arizona.
**FOR FURTHER INFORMATION CONTACT:**
Catherine Valladolid, EPA Region 9, (415) 947-4103, *[email protected].* The final Order and Petition are available electronically at: *https://www.epa.gov/title-v-operating-permits/title-v-petition-database.*
**SUPPLEMENTARY INFORMATION:**
The EPA received a petition from the Center for Biological Diversity, Patagonia Area Resource Alliance, Sierra Club, Arizona Mining Reform Coalition, Calabasas Alliance/La Alianza Calabasas, and Friends of the Santa Cruz River dated September 13, 2024, requesting that the EPA object to the issuance of operating permit no. 96653, issued by the ADEQ to Hermosa in Santa Cruz County, Arizona. On May 30, 2025, the EPA Administrator issued an order granting in part and denying in part the petition. The order explains the basis for the EPA's decision.
Sections 307(b) and 505(b)(2) of the CAA provide that a petitioner may request judicial review of those portions of an order that deny issues in a petition. Any petition for review shall be filed in the United States Court of Appeals for the appropriate circuit no later than December 1, 2025.
Dated: September 19, 2025.
Michelle Angelich,
Acting Director, Air and Radiation Division, Region IX.