Smuggler Mountain sits in Aspen, Pitkin County, Colorado. Silver mining ran there from 1879 to 1920, leaving the soil and groundwater contaminated with lead and cadmium. EPA added the site to the National Priorities List in June 1986 and removed it in September 1999 after cleanup construction was completed. Even so, the site remains under active monitoring and management, and a combined remedial investigation and feasibility study for the residential area is underway, with completion estimated between October and December 2027.
The site is split into two main operable units. The residential area, Operable Unit 1, covers about 116 acres and includes condominiums, mobile home parks, a tennis club, and single-family homes. Cleanup there involved capping heavily contaminated soils with 12 inches of clean fill, connecting properties to municipal water, and setting up a blood lead surveillance program for children. The mine area, Operable Unit 2, was regraded in 1995 to control erosion and dust, and fencing was installed to limit access. One portion of the site, OU2, does not yet have institutional controls in place.
Institutional controls are special rules that govern how the land can be used. Anyone disturbing more than 1 cubic yard of soil must get a permit first and follow dust suppression and contamination removal procedures. All areas must keep plant or hard surface cover to reduce erosion, and all landscaping must comply with these rules. Pitkin County Public Health conducts routine site visits to check compliance. Pitkin County is the responsible party for ongoing monitoring and management.
EPA is currently evaluating risks from lead in soils and yards under the Lead Directive, with a focus on children under 7 and pregnant or nursing women. Families with children under 7 who have not had soil replaced at their property are advised to have their children tested for lead annually. EPA and the Colorado Department of Public Health and Environment plan to coordinate on proposed changes and will seek public feedback. Five-year reviews confirm the remedy continues to protect human health and the environment, with the next review estimated between February and April 2027. Human exposure assessments have not yet produced data reliable enough to confirm that all exposures are fully controlled.
Community members can contact EPA's Community Involvement Coordinator or the Remedial Project Manager. For state-related questions, contact the Colorado Department of Public Health and Environment. Pitkin County Environmental Health is also available. Public records are also available at the Pitkin County Public Information Repository or by calling the EPA Superfund Records Center in Denver at (303) 312-7273.
