New Developments on the Horizon for the Eagle Mine
Long-time residents of the Eagle Valley remember a time nearly 30 years ago when the Eagle River ran orange. Linda Jones, who worked at Battle Mountain High School, would pass by the river and its orange-stained rocks on her way to work, football games, and ski practices. Joe Macy and his colleagues at Vail Resorts (then Vail Associates) dealt with blowing orange snow on Beaver Creek’s ski slopes in the winter of 1989-90, as their snowmaking process pulls water straight from the Eagle. Those who weren’t around in the eighties might not realize that the scene at the Eagle River was not unlike the 2015 Gold King Mine spill on the Animas River. The leaching of hazardous heavy metals into the lifeblood of the Eagle Valley eventually caused the mining area to be declared a Superfund Site by the U.S. Environmental Protection Agency in 1986.
Gold and silver mining activity in the 235-acre area dates back to the 1870s, until lead and zinc mining took over in 1905. Ownership of the operation changed hands multiple times, until 1984, when the mine operator, Glenn Miller, went into bankruptcy and failed to pay the electricity bills. Without electricity, the water pumps in the mine stopped running and the mine workings began to flood. For the next five years, the water level in the mine continued to creep higher, until finally spilling over and flooding the river with lead, cadmium, copper, arsenic and zinc. Water quality began suffering long before the spill, however, as up until the Clean Water Act of 1972 was enacted, discharging contaminated water into the river was a perfectly legal and common practice.
The State of Colorado and the EPA both filed separate lawsuits against the former and current mine operators resulting in the cleanup being governed by two settlement agreements. Today, the site is owned by Battle Mountain, but the successor of Gulf + Western—CBS Corporation—is still paying for the cleanup and will continue to in perpetuity.
Over the past three decades, multiple agencies and partners have worked together to remediate, monitor, and improve the cleanup and the Eagle River. In many ways, the Superfund Site is an example of a very successful remediation in Colorado. Ore was originally processed through roasting and magnetic separation, resulting in metals-laden roaster waste. The tailings from the milling process also contained high concentrations of metals and were slurried through a pipeline away from the mine area. The deposited waste led to acid mine drainage. To date, all of the roaster waste and tailings that threatened human health and water quality have been consolidated from the old tailings pile, capped with a protective cover and revegetated to prevent any further groundwater contamination. Contaminated groundwater is currently treated at a water treatment facility before entering the river. Institutional controls and monitoring were established around the waste rock piles to determine acid generation potential and the water quality impact from runoff. The EPA also created secondary cribbing walls beneath Belden as a safeguard from waste rock crumbling into the Eagle.
Though extensive remediation has occurred on site, the primary remaining concern is water quality and the ecological risks to fish and the tiny aquatic insects they feed on. The Eagle River is currently being managed as a brown trout fishery under Colorado Parks and Wildlife. In 2008, the Colorado Water Quality Control Commission set new standards for cadmium, copper, zinc, and arsenic levels. The change in standards required a new “feasibility study,” a Superfund process for the development and evaluation of new plans for cleanup. Today, the need for further cleanup is clear as the metal levels tend to exceed limits in March and April, as the snow is melting at the Eagle Mine site but the river hasn’t hit peak flow yet.
It’s important to note while arsenic levels peak in the spring, they are still well below limits for safe consumption of fish. The highest arsenic level is about .31 micrograms per liter (ug/L), while the Colorado Department of Public Health and Environment sets the standard for safe fish consumption at 7.6 ug/L, and under the Safe Drinking Water Act the limit is 10 ug/L. At a recent panel discussion of the Eagle Mine, both project managers from the EPA and CDPHE said they would let their kids and pets play in the river, and eat a fish from it as well.
The EPA broke the site into three manageable operable units (OUs): OU1 deals with site-wide water quality; OU2 is concerned with human health, primarily in the town of Gilman; and OU3 encompasses the North Property Redevelopment, or the Battle Mountain Project. The EPA and CDPHE have recently released Proposed Plans for Operable Units 1 and 3, which can be found online here and here or at the Minturn Town Hall. These new plans outline different alternatives for future remediation of the Superfund Site, to both bring metal concentrations into compliance in the spring as well as address land use changes in the future. Public comments on the plans will be accepted until September 10th of this year and can be submitted by email or mail—the addresses for each can be found within the plans. As these Plans are the first step in determining the next actions in the ongoing cleanup of the Superfund site, the Watershed Council encourages the community to read the plans and provide comments.
Lizzie Schoder is the Education and Outreach Coordinator for Eagle River Watershed Council. The Watershed Council has a mission to advocate for the health and conservation of the Upper Colorado and Eagle River basins through research, education, and projects. Contact the Watershed Council at (970) 827-5406 or visit