The U.S. Supreme Court declined on Tuesday to hear a Native American group’s bid based on religious rights to block Rio Tinto (RIO.AX), opens new tab and BHP (BHP.AX), opens new tab from gaining control of Arizona land needed to build one of the world’s largest copper mines - a project situated on land long used for Apache sacred rituals.

The project is 55% owned by British-Australian mining company Rio Tinto and 45% by Australian mining company BHP. Rio Tinto is the project’s operator. Both companies have spent more than $2 billion on the project without yet producing any copper.

Conservative Justices Neil Gorsuch and Clarence Thomas dissented, with Gorsuch calling the court’s decision a “grave mistake” that would allow the government to destroy the Apaches’ sacred site without even at least hearing arguments in their case.

“Just imagine if the government sought to demolish a historic cathedral on so questionable a chain of legal reasoning,” Gorsuch said. “I have no doubt that we would find that case worth our time.”

The destruction of the sacred site also would violate a 1852 treaty promising that the U.S. government would protect the land and “secure the permanent prosperity and happiness” of the Native American tribe, the plaintiffs said.