Recent images of the Van 4 uranium mine show a dark rig towering above a sagebrush and juniper mesa. Beside the scaffolding sit piles of loose white rocks and two metal buildings, one of which drips insulation from its ruptured ceiling. The site is one of western Colorado’s active uranium mines. But it looks deserted.

The operator, Piñon Ridge Mining, LLC, a subsidiary of Western Uranium & Vanadium Corp., is waiting for the price of uranium to rebound before firing up the mine again. The last time that happened was 30 years ago.

Just how long mines like the Van 4 should be allowed to remain open — but idle — has long been a point of contention in Colorado between environmentalists and mine owners.

Environmentalists argue the site should have been cleaned up and restored to sagebrush scrub decades ago.

But the Colorado Mined Land Reclamation Board, an eight-member panel appointed by the governor that enforces the state’s mining laws, has allowed mining companies to delay tearing down their operations by granting mine owners reclamation exemptions, known as “temporary cessation” permits.

This delay has frustrated environmental advocates. They see the unremediated sites as threatening wildlife habitat, water quality and a new West End economy based on recreational opportunities. They believe companies have relied on temporary cessation permits to sidestep environmental regulations requiring them to close and clean their all-but-shuttered mining operations.

And last week, the Colorado Court of Appeals agreed with them.

The court ruled the state regulatory board “abused its discretion” by granting two five-year temporary cessation permits to Piñon Ridge Mining, which owns the Van 4 site. After 10 years of sitting idle, the court said, the Van 4 operation must be terminated and the owner must fully comply with reclamation requirements, restoring the site closer to its natural condition.

The owner of the Van 4 mine said the court’s opinion could have sweeping consequences for the mining industry.

“The Van 4 is an insignificant mine, but this decision is going to be far-reaching in Colorado,” said George Glasier, founder, president and CEO of Western Uranium & Vanadium Corp. “It’s a major blow to mining in Colorado.”

Owners of the state’s 29 active uranium mines — 16 of which have been granted temporary cessation permits, according to state data — may have to begin tearing down rigs and buildings and testing for radiation. The state does not yet know how many mines are past due for reclamation, according to the court’s interpretation. But it knows there are several.

“Those sites will very likely need to be reclaimed in accordance with this order,” said Ginny Brannon, director of the Division of Reclamation, Mining and Safety.

The state estimates the federal Department of Energy holds about $14.5 million in bonds that companies front to ensure resources are available to restore closed mining operations.

Leave this field empty if you're human:

Environmental groups see no indication the post-Cold War uranium bust will turn around anytime soon. The court’s opinion may have just closed a legal loophole, they say, putting a nail in the coffin for so-called “zombie mines” that have been inactive for decades as owners wait for the next boom.

“This could be a turning point,” said Travis Stills, an attorney from Durango who joined the legal team that appealed the Colorado Mined Land Reclamation Board’s 2017 decision granting Piñon Ridge Mining a second five-year cleanup exemption.

Most active uranium mines in Colorado tap into the uranium-rich Uravan mineral belt, which follows the Dolores River corridor. This area is home to the Gunnison sage grouse, a threatened bird under the Endangered Species Act. Some uranium mines leak heavy metals into nearby water sources. In 2010, the Denver Post reported the Schwartzwalder Mine was leaking arsenic, radium and uranium into a creek feeding the Ralston Reservoir, which provides some of the drinking water for 1.4 million residents in Denver. Since then, a remediation program has begun.

The state has not monitored the Van 4 site for water contamination or radiation. The site is on an arid mesa above the Dolores River drainage, which carves through red rock canyon country below. Radiation is tested after the site is reclaimed, a state official said.

These dormant uranium mines are not projected to open anytime soon. The spot price for uranium is currently $25 per pound, far below the price at which it is profitable to mine. But the energy industry is lobbying the Trump administration to require utilities that own nuclear power plants to purchase more domestic yellowcake with the hopes of driving up demand.

Economics aside, Stan Dempsey, president of the Colorado Mining Association, said these inactive mines should remain open so that the U.S. has a source of domestic uranium. It comes down to a question of national security, he said.

“Should we rely on uranium supplies from other countries?” Dempsey said. “Once you finish the reclamation process, it will be difficult to access those minerals again. I think that’s a judgment call the state has to decide.”

A previous version of this story said the opinion was written by Judge Michael A. Martinez. It was updated on Thursday to reflect that a three-judge panel wrote the opinion. It was also updated to specify that the Department of Energy holds reclamation bonds, not the state.