WASHINGTON— Conservation and community groups today sued the Environmental Protection Agency over its delay in responding to objections filed over an Arizona air pollution permit for a new heavy metals mine in the Patagonia Mountains south of Tucson.

The lawsuit aims to compel the EPA to reject an Arizona Department of Environmental Quality permit allowing a multinational mining company, South32, to construct and operate the Hermosa heavy metals mine. The mine threatens to release hundreds of tons of toxic air pollution every year, putting clean air, biodiversity and the health of nearby communities at risk.

“Clean air delayed is clean air denied,” said Jeremy Nichols, a senior advocate at the Center for Biological Diversity. “The EPA needs to stop dragging its feet and hold South32 and the Arizona Department of Environmental Quality accountable for protecting people and communities.”

In a legal petition filed in September, a coalition of health and environmental groups requested the EPA object to the air pollution permit for the Hermosa mine. The mine would be dug into the Patagonia Mountains, a biodiversity hotspot and a drinking water source for Santa Cruz County. It would be located only five miles from the town of Patagonia, a community sustained by local businesses and ecotourism.

“Industrial exploitation of the Patagonia Mountains threatens the prosperity of this region and the very survival of the Patagonia community,” said Carolyn Shafer with the Patagonia Area Resource Alliance. “South32’s Hermosa mine should never have been issued an air pollution permit. We need the EPA to step up and protect the health and wellbeing of all creatures that live in and near the Patagonias.”

Despite widespread opposition, the state approved the Hermosa mine’s air pollution permit in August.

Under the federal Clean Air Act, the air pollution permit is subject to EPA review. The coalition urged EPA to reject the permit, citing numerous deficiencies including a lack of enforceable limits on particulate matter pollution, inadequate pollution monitoring and failure to assure best available pollution controls.

Although the EPA was required to grant or deny the petition within 60 days, the agency has yet to respond. With the transition in administrations, more delay is likely without legal action.

If the EPA grants the groups’ petition, the Arizona Department of Environmental Quality will have 90 days to fix the permit, or the EPA will be required to take it over and potentially deny it.

Today’s lawsuit was filed by the Center for Biological Diversity and Patagonia Area Resource Alliance in U.S. District Court for the District of Columbia. This latest legal challenge follows a 2023 lawsuit over the U.S. Forest Service’s approval of South32’s mining exploration in the area.

More information about the Center’s fight against air pollution is available at Protecting Air Quality Under the Clean Air Act.