Conservation groups contest discharge permit at Grand Canyon-adjacent uranium mine

Conservation groups slammed Arizona’s environmental agency on Friday for approving a uranium mine’s discharge permit — a move they claim could threaten groundwater resources at the nearby Grand Canyon National Park.

The groups argued that the “aquifer protection permit” in question, which technically serves to tighten government oversight of a polluter’s operations, could put the area’s aquifers and springs at risk by enabling the mine’s continued operations.

The Pinyon Plain Mine, located about 15 miles south of the Grand Canyon, has a history of flooding as it depletes shallow groundwater aquifers that express just south of the canyon at South Rim Springs, the groups said in a joint press release on Friday morning.

They argued that continued operations of the mine, owned by Energy Fuel Resources, could also permanently pollute the deep aquifers that feed into Havasu Creek. Members of the Havasupai Tribe, they noted, have repeatedly called for the closure of the facility. 

“Uranium mines do not belong among the complex groundwater systems that surround the Grand Canyon and Pinyon Plain Mine is a perfect example of why,” Amber Reimondo, energy director for the Grand Canyon Trust, said in a statement.

“Uranium contamination in a system like this is forever and while the mining company can walk away, the Havasupai Tribe can’t,” Reimondo added.

The specific permit approved on Thursday — an aquifer protection permit — is mandatory for any facility that releases pollutants into the groundwater, according to the Arizona Department of Environmental Quality (ADEQ).

This type of permit requires such facilities to meet the state’s aquifer water quality standards while showing that it is using best available technologies to minimize such discharges.

The ADEQ’s permit review describes the site in question as “an underground uranium mine” that accesses uranium ore “to a depth of up to 1,997 feet below ground surface.”

Analyses included in the review conclude “that the natural hydrogeologic protections at the mine site are expected to prevent any potential impacts to groundwater resulting from mining operations.”

But the conservation groups protesting the permit argued that in late 2016, mineshaft drilling pierced the area’s shallow aquifers, causing water pumped from the mine to spike to 1.4 million gallons from 151,000 gallons the previous year.

Inflow of water has ranged from 8.8 million gallons in 2017 to 10.76 million gallons in 2019, and in 2021, the mine took in 8.3 million gallons, according to the groups.

Meanwhile, since 2016, dissolved uranium in the water has consistently surpassed federal toxicity limits by more than 300 percent and arsenic levels by more than 2,800 percent, the groups noted.

“Neither regulators nor the uranium industry can ensure that mining won’t permanently damage the Grand Canyon’s precious aquifers and springs,” Taylor McKinnon of the Center for Biological Diversity said in a statement.

“This permit strenuously ignores science showing the potential for deep aquifer pollution, and in a region still plagued by seven decades of uranium industry pollution, risking more, as this permit does, is dangerous,” McKinnon added.

In response to the conservation groups’ claims, the ADEQ said that the mine has been “studied, scrutinized and litigated for over 30 years” and therefore “has an extensive record.”

“Federal courts have rejected all claims in two lawsuits that the mine will adversely impact groundwater and seeps and springs in the Grand Canyon,” a statement from the ADEQ said, adding that the U.S. District Court and the Ninth Circuit concluded that the mine could operate.

The statement explained that “although the mine is already lawfully permitted,” the ADEQ decided to require the mine’s operator to apply for an aquifer protection permit following tribal consultation and public comments — and “out of an extraordinary abundance of caution.”

Among the permit’s conditions are a prohibition on mining in the region’s Coconino aquifer, as well as requirements for lining the bottom 12 feet of the mine shaft. The operator also must install at least three additional groundwater monitoring wells in the Coconino aquifer and conduct 30 years of monitoring whenever the facility does close its doors, according to the ADEQ.

As a result of that permit, the statement added, the mine will now be “the most tightly regulated uranium mine in Arizona, and possibly the most heavily regulated conventional uranium mine in the United States.”

The conservation groups stressed, however, that they have repeatedly urged the ADEQ to limit the operator’s permit to mine closure, post-closure maintenance and full bonding, while thousands of Arizonans have likewise advocated for the mine’s shutdown.

“Contaminated waters left behind from the previous uranium boom-bust cycle already plague the region,” Alicyn Gitlin, of the Sierra Club’s Grand Canyon Chapter, said in a statement.

“We shouldn’t further risk our life-giving water, especially in the midst of this megadrought,” Gitlin added. “Grand Canyon’s springs are vital to people and wildlife and extremely vulnerable to contamination and depletion.”