GRAND CANYON NATIONAL PARK — An Arizona lawmaker is renewing his push to halt uranium mining near the Grand Canyon, outlining a proposal Saturday that would make permanent a moratorium on new claims across 1 million acres of public lands.

Rep. Raúl Grijalva has introduced other versions of what he's calling the “Grand Canyon Centennial Protection Act” several times in recent years, but he's likely to find stronger support this time in the Democratic-controlled House, where he is chairman of the Natural Resources Committee.

On Saturday, he pitched the idea at the Canyon, flanked by Havasupai, Hualapai, Hopi and Navajo tribal leaders, in a building near the park’s South Rim that was packed with park visitors, tribal members and environmental advocates.

“Protecting the canyon is just, it’s overdue and it’s life-affirming,” Grijalva said, gesturing to the group. “The public wants us to do it, the economies of the region need it and the Grand Canyon’s future depends on it.”

Former Interior Secretary Ken Salazar imposed the original 20-year moratorium on new mining claims in 2012.

Grijalva made the announcement just days before the 100th anniversary of the Canyon's status as a national park, and just days after news broke about buckets full of uranium ore sitting in a South Rim museum, exposing visitors and employees to small amounts of radiation.

READ MORE: Are uranium mines near the Grand Canyon hazardous to wildlife?

Tribal leaders line up behind bill

The presence of the tribal leaders signaled the importance of the Canyon to surrounding indigenous communities. Some of the tribes are still dealing with the effects of uranium mines that sickened or killed people who lived or worked nearby. Tribal leaders fear new mines could further contaminate the environment.

Richard Powskey, a Hualapai tribal council member, said protecting the Grand Canyon's regional watershed has been a decades-long effort that the communities are not ready to give up.

“This water cannot continue to be threatened by these mining operations,” Powskey said, adding that native people are the most affected. “The damage from these mines lasts for a while and brings lasting health concerns and other adverse effects.”

Ethan Aumack, executive director of the Grand Canyon Trust, an advocacy group, said contaminated water is pumped from one operation, the Canyon Mine, even though it has not produced new ore for years.

Mines, he said, "are inactive because uranium remains too costly to mine." The group has released a new report arguing that uranium mining in the Grand Canyon region is not necessary for national security.

"It is uneconomic," Aumack said. "And it is a threat to our tourism-based economies."

Uranium mining is a toxic and touchy topic for Arizona politicians, who laud the cultural significance the Grand Canyon holds for tribes, as well as the ecological importance as the cradle of the Colorado River.

But the rich uranium deposits sitting outside the park's boundaries are highly sought after and many local leaders believe the state can pursue economic interests while also preserving the Canyon.

President Donald Trump issued an executive order about two years ago that told federal agencies to examine policies that could slow energy development on public lands. One of those recommendations was reversing the moratorium on uranium mining near the park, which has been upheld in court.

While existing claims remain for now, Republican lawmakers have pushed to lift the ban, which would open up 1 million acres around the Canyon to developers.

Gosar: Bill is 'misguided quest'

One of the harshest critics of the moratorium is Rep. Paul Gosar, R-Ariz. Gosar, who has called the mining of uranium a “national security issue” and vital to the United States’ energy independence, took aim at Grijalva’s bill in a statement, calling it a “misguided quest.”

In that same statement, Rep. Andy Biggs, R-Ariz., members of the Congressional Western Caucus and mining stakeholders condemned the proposed bill and reiterated their opposition to the restrictions on a huge reserve of breccia pipes in the Grand Canyon region. Some of those pipes are essentially plugs of high-quality uranium, which Gosar stressed are “far outside” the canyon.

"There is no reason America should be importing 97 percent of our uranium necessary for domestic reactors from countries with Russian influence when we have an ample supply here at home,” Gosar said in the statement, adding that it would create jobs and provide energy to communities. “At a time when we should be celebrating the Centennial of the Grand Canyon, Rep. Grijalva's bogus effort distracts from what should be a joyous bipartisan celebration."

While energy independence is on the minds of Democrats and conservationists like Grijalva, they say the risk from mining is not worth potentially damaging the delicate and thriving ecosystem that inhabits one of mankind's timeless treasures.

Efforts to push the permanent ban through Congress have stalled in recent years, never earning a hearing from a Republican-controlled House. Grijalva said he was confident he could get it to the floor of the Democratic House. If passed, it would be placed in the hands of a Republican-led Senate and face a doubtful future.

The draft bill already has a cosponsor, Rep. Tom O'Halleran, D-Ariz., who stressed the connection people in Arizona have to the Canyon and implored people to think about the merits of the projects, some of which are within walking distance of the canyon.

“This is not what America is about,” O’Halleran said, referring to the lasting environmental damage of some of these mines. “The health of our children needs to come first, it cannot be a second thought.”

Andrew Nicla covers the environment for the Republic. Reach him at andrew.nicla@gannett.com or on Twitter @AndrewNicla.

Environmental journalism 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 environment.azcentral.com and at OurGrandAZ on Facebook, Twitter and Instagram.