The Arizona Department of Environmental Quality, or ADEQ, is asking for public input on whether to approve a groundwater permit for a proposed copper mine in southern Arizona. 

The proposed Copper World project would  be a multi-pit copper mine in the Santa Rita mountains southeast of Tucson. Copper World Inc. is a subsidiary of Hudbay Minerals. The Canadian mining company proposed another open-pit mining venture in the Santa Ritas called Rosemont Copper Mine several years ago, but it was later blocked in federal court. 

Russ McSpadden with the conservation group Center for Biological Diversity says just like Rosemont, the proposed Copper World mine could affect the ecosystem of the Santa Ritas and the Santa Cruz River nearby.

"You know, a really significant sky island mountain range, and a really significant river. So the groundwater there is really relevant to our survival," he said.   

The Santa Rita Mountains are some of a handful of so-called sky islands across southern Arizona and northern Mexico, where drastically different ecosystems are contained in a single range. The range is also home to endangered, cross-border species like jaguars. 

ADEQ is one of several agencies that must sign off on mining ventures and other projects that could use, discharge into and potentially contaminate the state’s groundwater supply. The agency released a draft permit for the mining project early this month and is accepting comments till Feb. 25.

McSpadden says he and other advocates are asking the agency to extend the comment period and host public meetings, so community members have time to sort through the science, and weigh in. 

"They’ve put this out, they’ve published this, and they are basically saying that they expect the public to do in approximately 50 days what the agency took 455 days to do," he said. 

Trveor Baggiori, water quality division director of the Arizona Department of Environmental Quality, says his agency is aware of the request made by some advocates to extend the comment period, but no decision has been made on that yet. He says all mining operations proposed in Arizona must get what's called an Aquifer Protection Permit from ADEQ. He says the agency has been assessing Copper World's permit request for about a year.

"We get application from companies that are regulated under that program, we review that application in a very technical way, including hydrogeology as well as engineering, to ensure that that facility and its discharges are going to be protective of Arizona's groundwater," he said. "They have to demonstrate things that are in their discharge, what impact that discharge is going to have on groundwater in their area, to ensure they are meeting standards outside of the boundary of their property, and they're not contaminating groundwater outside the groundwater of their property."

Baggiori says applicants must present details of the facility, including discharge locations and other functions. ADEQ reviews those materials and presents a draft version of the permit to the public for comment. The agency approved an Aquifer Protection Permit for the Rosemont Copper Mine a few years ago, but the project's federal water-use permit was later revoked. 

In an email response to questions, a Hudbay Minerals spokesperson said the Aquifer Protection Permit is one of two ADEQ permits Copper World needs to begin operations — the other, air quality-focused permit is currently being processed and the company expects to have both by the middle of this year.

If it moves forward, the venture could provide more than 400 direct jobs in Arizona and contribute more than $170 million in taxes during its 15-year lifespan, according to the Hudbay spokesperson. 

EDITOR'S NOTE: This story has been updated to reflect that the proposed Copper World mine is near the Santa Cruz River.