The Eagle River roils with spring runoff in June 2011 near Edwards, Colo. Photo/Allen Best
Eagle River Basin
Here’s the release from the Environmental Protection Agency (Jennifer Chergo):
The U.S. Environmental Protection Agency (EPA) and the Colorado Department of Public Health and Environment (CDPHE) today released two Proposed Plans for environmental remediation at the Eagle Mine Superfund Site. Both Proposed Plans focus on further reducing heavy metal contamination created by nearly one hundred years of mining activity at the site.
“The cleanup proposals represent both EPA and CDPHE’s commitment to protect human health and the environment at the Eagle Mine Superfund Site,” said Acting Regional Administrator Deb Thomas. “These plans also highlight EPA’s commitment to bringing contaminated lands back to health and reuse.”
The Eagle Mine Superfund Site is located in Eagle County, Colorado. The site is defined as the area impacted by past mining activity along and including the Eagle River between the towns of Red Cliff and Minturn. Mining activities at the Eagle Mine began in 1879 and continued until 1984. EPA listed the site on the National Priorities List (NPL), commonly known as the list of Superfund Sites, in 1986 because of the mine metals discharge, uncontrolled mine waste piles and the close proximity of the population to the mine and associated features. To better manage the site, EPA divided it into operable units (OUs). OU1 focuses on protecting surface water by reducing metals loading from the site to the Eagle River. OU2 focuses on potential human health risks from contaminated soils in the abandoned company town of Gilman. OU3 focuses on soil remediation necessary to protect human health due to planned future development by the current landowner.
EPA issued a final Record of Decision (ROD) for OU1 in 1993 and a final ROD for OU2 in 1998. Over the years, all required environmental cleanup work has occurred at the Eagle Mine Superfund Site under a number of state and federal directives. Response actions at the site addressed the major sources of metals contamination to the Eagle River, including the old and new tailings pile, rex flats and various roaster waste piles near Belden. In 2001, EPA declared all cleanup construction activities complete at the Eagle Mine Superfund Site, except for ongoing operation and maintenance of remedial features like the water treatment plant. Remediation conducted to-date resulted in significant improvement in water quality and reduction in risk to human health and the environment. Continued operation of the existing remedy, including drawdown from the mine pool and treatment at the water treatment plant, is required to maintain this condition. Contaminant concentrations in surface water and groundwater have decreased, and the aquatic ecosystem continues to show signs of recovery.
In 2009, water quality standards established by the Colorado Water Quality Control Commission specifically for the Eagle Mine site became effective. Water quality monitoring in the Eagle River revealed that the water quality standards for cadmium, copper and zinc are not attained in March and April of most years. In response, the Proposed Plan released today for OU1 describes a number of alternatives designed to further reduce metals loading to the Eagle River. The preferred OU1 alternative includes the collection and treatment of groundwater from Belden and at the mouth of Rock Creek.
The Proposed Plan for OU3 presents cleanup alternatives focusing on soil remediation necessary to protect human health should future development occur. EPA created OU3, after a developer purchased a large portion of the Eagle Mine Superfund Site in 2004 with plans to develop the property into a private, residential community. The preferred alternative includes a combination of the following elements for areas at OU3 proposed for development: placing a soil exposure barrier; grading the site; placing institutional controls and conducting monitoring; and/or demolishing structures.