The U.S. 9th Circuit Court of Appeals on Tuesday upheld a 20-year ban on new uranium mining on public land near the Grand Canyon, while also striking down a challenge to an existing uranium mine south of Grand Canyon National Park.

In its opinion, the court ruled that the ban, imposed in 2012 under former President Barack Obama, lines up with the Constitution and federal environmental laws. However, it ruled that a mine six miles south of the national park had a right to operate.

"We upheld the decision of the Secretary of the Interior to withdraw, for twenty years, more than one million acres of public lands around Grand Canyon National Park from new mining claims," the opinion states. "That withdrawal did not extinguish 'valid existing rights.'"

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The ban was put in place by the U.S. Department of the Interior under former Secretary Ken Salazar. It came as mining operations were renewing their interest in uranium deposits near the Canyon.

A spokeswoman for the Department of the Interior declined to comment Tuesday and said the Department of Justice handles questions on litigation.

A DOJ spokesman declined to comment and did not respond to further questions.

Symbolic and economic value

The suit — led by the Havasupai Tribe, Grand Canyon Trust, Center for Biological Diversity and Sierra Club — sought continued protections under the standing mining ban.

"The Havasupai people have been here since time immemorial. This place is who we are,” Havasupai Tribal Chairman Don Watahomigie said in a statement. "This place, these waters and our people deserve protection. The lives of our children and the purity of our waters are not to be gambled with and are not for sale."

In addition to the Canyon's symbolic value, supporters of the suit argued it has significant economic value.

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Grand Canyon National Park in 2016 contributed about $904 million to local economies and supported nearly 9,800 jobs, according to the National Park Service.

"The Department of the Interior’s decision to protect one of the world’s most enduring landscapes and the sustained health of indigenous communities that live within the watershed of the Grand Canyon was a strong and appropriate one,” said Kevin Dahl, Arizona senior program manager for the National Parks Conservation Association.

About 1 million acres adjacent to the Grand Canyon are protected under the ban, though the continued exception for existing mines came as a disappointment to the plaintiffs in the suit.

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"We are disappointed that the court did not uphold the challenge to Canyon Mine, however, and we will continue to do all we can to ensure permanent protection of these lands," Sierra Club Grand Canyon chapter director Sandy Bahr said in a statement Tuesday.

The appeals court's decision comes on the heels of President Donald Trump's decision to drastically shrink two national monuments in Utah — a decision a Navajo Nation attorney called a "slap in the face."

Interior Secretary Ryan Zinke, has drawn conservationists' ire for his review of national monuments, in particular those established under former Presidents Obama and Bill Clinton.

He initially ordered a review of the Grand Canyon-Parashant National Monument, north of the Canyon, an area that sits atop uranium deposits. Ultimately, he left the monument unchanged.

In a statement Tuesday, Sen. Maria Cantwell, D-Wash., criticized Zinke for "ongoing actions to hand over public lands to extractive industries instead of ensuring taxpayers get a fair deal."

A history of litigation

The suit is far from the first for the uranium mining ban.

In 2012, the year it was put in place, The Republic reported that the National Mining Association and the Nuclear Energy Institute challenged the ban's constitutional merits.

Hal Quinn, president and CEO of the mining group, said at the time that the Interior Department "offered no evidence ... that a million-acre land grab is necessary to avoid environmental harm."

Taylor McKinnon, of the Center for Biological Diversity, said in a statement Tuesday that opening exposing the land to uranium mining could do harm to its aquifers.

“Any effort to lift this crucial ban will meet fierce opposition,” his statement read. “There’s every reason to believe uranium mining could permanently damage Grand Canyon’s precious aquifers and springs. That’s an unacceptable risk, and it’s immoral of Congress and Trump to even consider it.”

What's next?

Although the mining ban has worked its way through the legal system, some believe this could be the end of the line.

Roger Clark, Grand Canyon program director for the Grand Canyon Trust, said he doesn't believe the case will end up before the Supreme Court.

"In both cases, the appellate court upheld the district court and there was no discrepancy in their rulings and there’s very little, I’m told by our attorneys, angle for appeal in either case," he said. "I’m not an attorney, so I’ll put that caveat in there."

Environmental coverage on azcentral.com and in the Arizona Republic is supported by a grant from the Nina Mason Pulliam Charitable Trust. Follow the azcentral and Arizona Republic environmental reporting team at OurGrandAZ on Facebook, Twitter and Instagram.

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