Pike Hill Copper Mine is an abandoned copper mine in Corinth, Vermont, made up of three historic mining areas: Union, Eureka, and Smith. EPA added it to the National Priorities List (NPL) on July 22, 2004. The site covers about 15 acres of waste piles containing roughly 85,000 cubic yards of material. A remedial investigation began in June 2005 and is expected to wrap up between September and November 2028, when EPA will also issue a Record of Decision (ROD). The ROD is the formal document that explains which long-term cleanup methods will be used.
The main contamination concern is acid mine drainage. When sulfide minerals in waste rock are exposed to air and water, they produce sulfuric acid. That acid dissolves metals, including aluminum, cadmium, cobalt, copper, iron, manganese, and zinc, into nearby water. Contaminated water flows into Pike Hill Brook and Cookville Brook Tributary #4. Copper levels in those streams have reached up to 444 times higher than Vermont Water Quality Standards. The damage to aquatic life is severe: fish mortality in the first mile below the mine discharge ranges from 85% to 100%, and the upper reaches of Pike Hill Brook are virtually fishless. All four miles of Pike Hill Brook and a 0.7-mile stretch of Cookville Brook Tributary #4 are designated as impaired waters. Three bat species near the site, including the federally endangered northern long-eared bat, also face potential exposure.
EPA selected a non-time-critical removal action (NTCRA) in September 2022 to address contamination before the long-term remedy is finalized. Phase 1 of that cleanup began construction in August 2025 and was largely complete by January 2026. It included clearing vegetation, installing erosion controls, stabilizing mine waste near mine openings in place, and building two sediment basins. EPA is now designing Phase 2, which will involve excavating and consolidating mine waste into an on-site containment cell that will be capped. The Phase 2 design is expected to finish in 2026. The site received funding from the Bipartisan Infrastructure Law to help speed up this work.
Between phases, EPA continues routine inspections and erosion and sediment control work. Institutional controls, including zoning restrictions that limit land use, are in place to reduce exposure while cleanup proceeds. Once the site is fully cleaned up, it could be reused for purposes such as parks, offices, or solar power generation.
Community members can stay involved through EPA's Community Involvement Plan for the site. EPA held a public information meeting on September 25, 2025, to update residents on Phase 1 and discuss Phase 2 plans. Questions can be directed to the EPA Community Involvement Coordinator or the Remedial Project Manager. Site documents are also available at Blake Memorial Library in East Corinth, Vermont, and at EPA Region 1 offices in Boston, Massachusetts.
