LEADVILLE, Colo. — Rust-colored piles of mine waste and sun-bleached wooden derricks loom above the historic Colorado mountain town of Leadville — a legacy of gold and silver mines polluting the Arkansas River basin more than a century after the city’s boom days.
Enter a fledgling company called CJK Milling that wants to “remine” some of the waste piles to squeeze more gold from ore discarded decades ago when it was less valuable. The waste would be trucked to a nearby mill, crushed to powder and bathed in cyanide to extract trace amounts of precious metals.
The proposal comes amid surging global interest in re-processing waste containing discarded minerals that have grown more valuable over time and can now be more readily removed. These include precious metals and minerals used for renewable energy that many countries including the U.S. are scrambling to secure.
### Global Interest in Mining Waste
The global interest in re-processing waste containing valuable minerals has sparked a revival in remining initiatives as companies seek to extract previously discarded minerals with increased value over time.
Backers say the Leadville proposal would speed cleanup work that’s languished for decades under federal oversight with no foreseeable end. They speak in aspirational tones of a “circular economy” for mining where leftovers get repurposed.
Yet for some residents and officials, reviving the city’s depressed mining industry and stirring up waste piles harkens to a polluted past, when the Arkansas was harmful to fish and at times ran red with waste from Leadville’s mines.
“We’re sitting in a river that 20 years ago fish couldn’t survive,” Brice Karsh, who owns a fishing ranch downstream of the proposed mill, said as he threw fish pellets into a pool teeming with rainbow trout. “Why go backward? Why risk it?”
Leadville — home to about 2,600 people and the National Mining Museum — bills itself as America’s highest city at 10,119 feet (3,0084 meters) above sea level. That distinction helped the city forge a new identity as a mecca for extreme athletes. Endurance race courses loop through nearby hillsides where millions of tons of discarded mine waste leached lead, arsenic, zinc and other toxic metals into waterways.
### The Vision of CJK Milling
The driving force behind CJK Milling is Nick Michael, a 38-year mining veteran who characterizes the project as a way to give back to society. Standing atop a heap of mining waste with Colorado’s highest summit, Mount Elbert, in the distance, Michael says the rubble has a higher concentration of gold than many large mines now operating across the U.S.
City Council member Christian Luna-Leal grew up in Leadville — in a trailer park with poor water quality — after his parents immigrated from Mexico.
### Environmental Concerns and Acknowledgment of History
Disadvantaged communities have historically borne the brunt of the industry’s problems, creating concerns about the potential environmental impacts and risks associated with remining in Leadville.
Economically favorable conditions mean remining “has caught on like wildfire,” said geochemist Ann Maest, who consults for environmental organizations including EarthWorks. The advocacy group is a mining industry critic but has cautiously embraced remining as a potential means of hastening cleanups through private investment.
CJK Milling could help do that in Leadville, Maest said, but only if done right. “The rub is they want to use cyanide, and whenever a community hears there’s cyanide or mercury, they understandably get very concerned,” she said.
Overseeing Leadville’s water supply is Parkville Water District Manager Greg Teter, who views CJK Milling as a potential solution to water quality problems.
Many waste piles sit over the district’s water supply, and Teter recalls a blowout of the Resurrection Mine compelled residents to boil their water because the district’s treatment plant couldn’t handle the dirt and debris.
More constant is the polluted runoff during spring and summer, when snowmelt from the Mosquito mountains washes through mine dumps and drains from abandoned mines.
Every minute, 694 gallons on average of contaminated mine water flows from Leadville’s Superfund site, according to federal records. Most is stored or funneled to treatment facilities, including one run by the U.S. Bureau of Reclamation.
Up to 10% of the water is not treated — tens of millions of gallons annually carrying an estimated six tons of toxic metals, U.S. Environmental Protection Agency records show. By comparison, during Colorado’s 2015 Gold King Mine disaster that fouled rivers in three states, an EPA cleanup crew inadvertently triggered release of 3 million gallons (11.4 million liters) of mustard-colored mine waste.
As long as Leadville’s piles remain, their potential to pollute continues.
“There are literally thousands of mine claims that overlay each other,” Teter said. “We don’t want that going into our water supply. As it stands now, all the mine dumps are … in my watershed, upstream of my watershed, and if they remove them, and take them to the mill, that’s going to be below my watershed.”
EPA lacks authority over CJKs proposed work, but a spokesperson said it had “potential to improve site conditions” by supplementing cleanup work already being done. Moving the mine waste would eliminate sources of runoff and could reduce the amount of polluted water to treat, said EPA spokesperson Richard Mylott.
Other examples of remining in the Rockies are in East Helena and Anaconda, Montana and in Midvale, Utah, Mylott said. Projects are proposed in Gilt Edge, South Dakota and Creede, Colorado, he said.
Despite the mess from Leadville’s historic mining, Teter spoke proudly of his industry ties, including working in two now-closed mines. His son in law works in a nearby mine.
“If it were not for mining, Leadville would not be here. I would not be here,” the water manager said.
“There are no active mines in our watershed, but I’m confident in what CJK has planned,” he said. “And I’ll be able to keep an eye on whatever they do.”
