The U.S. Supreme Court declined on May 27 to hear an appeal from a group of Apaches and others who wanted to block a copper mining project on Oak Flat, part of the Tonto National Forest in Arizona that the Western Apaches consider sacred.

Resolution Copper, a joint venture of mining firms Rio Tinto and BHP, says the site about 60 miles east of Phoenix near Superior, Ariz., contains one of the largest untapped copper resources in the world. The company hopes to remove 40 billion lb of copper from a deposit located 5,000 ft to 7,000 ft underground over 40 years at what would be the largest copper mine in North America. 

Vicky Peacey, general manager at Resolution Copper, said in a statement that the company is “pleased” with the court’s decision. 

“The Resolution Copper mine is vital to securing America’s energy future, infrastructure needs and national defense with a domestic supply of copper and other critical minerals,” Peacey said. 

Oak Flat is known as Chi’chil Biłdagoteel to the Apaches, who gather there for religious ceremonies they say cannot take place anywhere else. The site had previously been protected by Presidents Eisenhower and Nixon, and the National Park Service added Oak Flat to the National Register of Historic Places in 2016, though by then lawmakers had already approved a plan to swap 3.75 sq miles of Oak Flat to the mining companies in exchange for other land in Arizona. A group called Apache Stronghold filed a lawsuit against the government in 2021 seeking to block the land transfer under the terms of an 1852 treaty. 

Last year, the Ninth Circuit appeals court ruled against Apache Stronghold, and the group appealed again to the U.S. Supreme Court. The majority of justices denied the case, though Justice Neil Gorsuch, joined by Justice Clarence Thomas, dissented, calling the decision “a grievous mistake” on religious freedom grounds.

“Recognizing Oak Flat’s significance, the government has long protected both the land and the Apaches’ access to it,” Gorsuch wrote. 

“No more,” he added. “Now, the government and a mining conglomerate want to turn Oak Flat into a massive hole in the ground.” 

Map courtesy U.S. Supreme Court

Resolution Copper says it has shaped its plans with feedback, reducing the land exchange area from 3,025 acres to the 2,422 acres approved by Congress, and setting aside some land to protect. 

“More than a decade of extensive consultation and collaboration with Native American tribes and local communities has directly led to major changes to the mining plan to preserve and reduce potential impacts on tribal, social and cultural interests, and this ongoing dialogue will continue to shape the project,” Peacey said. 

Still, Apache Stronghold plans to continue fighting the project, Wendlser Nosie Sr. of the group said in a statement. He said he hopes to urge Congress to take action to stop the project.

“While this decision is a heavy blow, our struggle is far from over,” Nosie said. 

Last month, the U.S. Forest Service issued a notice that it would publish a final environmental impact statement and a draft record of decisions after 60 days.