Colorado Can’t Afford to Ignore Abandoned Mines
Note: This piece was published by The Denver Gazette on October 6, 2021.
Written by Quentin Septer
More than 23,000 abandoned mines litter Colorado’s Rocky Mountains, according to a joint report from the Colorado Department of Public Health & Environment and the Colorado Department of Natural Resources Division of Reclamation. Thousands of these mines have been leaching acid mine drainage pollution into the state’s watersheds for more than a century. And still, nothing is being done to stop them.
When mining operations upturn the earth, minerals like pyrite are exposed to the atmosphere. This process happens naturally, of course, at the slow, steady pace of erosion. But mining accelerates the process drastically. When water and oxygen encounter pyrite, a chemical reaction occurs, generating a solution of sulfuric acid and dissolved iron. Other metals like copper, lead and mercury dissolve in the runoff, as well. The end result is known as acid mine drainage—a concoction of highly acidic water and exorbitantly high quantities of heavy metals. And when rainfall and snowmelt accumulate in abandoned mine shafts, acid mine drainage tends to form en masse, and the pollution flows on into local streams, rivers, lakes and groundwater, where the health of fish and other aquatic organisms—along with human drinking water—are threatened.
The pollution flowing from a handful of Colorado’s abandoned mines has attracted the attention of the Environmental Protection Agency. Historically, Colorado has been home to hundreds of Superfund sites—locations so thoroughly polluted that the EPA, among other federal agencies, deem it necessary to step in and clean up the mess. At present, the EPA acknowledges 25 National Priorities List (NPL) sites in the state of Colorado; which are, in effect, Superfund sites in need of further assessment and cleanup. Ten of these sites were directly polluted by historic mining operations.
The vast majority of Colorado’s 23,000-plus abandoned mine sites and their discharge of acid mine drainage escape the scrutiny of the EPA, however. Officials have yet to perform even basic risk assessment analyses on an estimated 80 percent of historic mines populating the nation’s public lands. And among the mines that have been studied, cleanup actions have yet to be initiated in locales failing to meet Superfund criteria. But the fact that an abandoned mine site isn’t assigned Superfund status doesn’t mean such a site poses no threat to the environment. In Colorado’s San Juan Mountains alone, upwards of 400 neglected mines have been leaking a combined 15 million gallons of acid mine drainage into the San Juan and Animas watersheds per day, every day, for more than a century.
Colorado’s forlorn mine sites were established in accordance with the General Mining Act of 1872—a federal law authorizing and governing prospecting and mining claims on America’s public lands. The act is riddled with loopholes, permitting lax environmental safety protocols and hazardous concentrations of acid mine drainage to be discharged into a given mine’s surroundings without recourse. Complicating matters, the founders and operators of these mines died and disbanded long ago. Thus, identifying who, exactly, should be held accountable for these forgotten mine sites and their ongoing pollution of Coloradan and American watersheds remains an open question.
“Because historic draining mines may continually discharge high concentrations of pollutants,” the 2017 Colorado Abandoned Mines Water Quality Study reads, “perpetual treatment or long-term remedies are required.” And such remedies cost a lot of money. “It is a long standing policy of the Water Quality Control Division to not pursue discharge permits for mining features that are inactive with undetermined ownership. There are also liability concerns over the treatment of discharge from abandoned mines.” Plainly, unless a site has already been assigned Superfund status, any agency or organization ambitious enough to so much as attempt to remedy the pollution flowing from a given mine site would, by laws specified in the General Mining Act of 1872, assume liability for reducing and maintaining pollution levels at that site to Clean Water Act standards, “for an indefinite period of time.” A costly, long-term project, to be sure.
It’d be an understatement to say that government agencies and environmental groups are financially disincentivized from cleaning up Colorado’s historic mine sites. But that is, in effect, what the issue boils down to. It’s a matter of incentives, on some level, and if taking on an issue means committing financial suicide, solutions to such problems are apt to remain illusive. Thus, until regulatory reform is enacted and legislation is passed that better incentivizes the cleaning up of Colorado’s abandoned mines, proper action effectively can’t be taken to remedy this issue, and untold volumes of acid mine drainage pollution will continue to flow into Colorado’s watersheds for the foreseeable future—home to the headwaters of the country itself.
And of course, the problems posed by abandoned mines and acid mine drainage pollution aren’t unique to Colorado, though they are pronounced in the Centennial State. More than half a million abandoned hardrock mines litter Bureau of Land Management, National Park Service, and National Forest Service lands across the nation. And with the current resources, staffing and funding allocated to this issue, the BLM estimates that it will take about 500 years to inventory all of these historic mine sites.
How long the cleaning up will take from there is anybody’s best guess.