Ore Knob Mine

Overview

Ore Knob Mine sits in Ashe County, North Carolina, and was added to the EPA's National Priorities List (NPL) in September 2009. Copper mining at the site ran intermittently from the 1850s through 1962, leaving behind roughly 720,000 cubic yards of tailings. Underground mines stretch more than 4,000 feet long and 1,000 feet deep, and many are now partly flooded with mine-impacted groundwater that keeps releasing contamination into the surrounding environment.

The site is contaminated with metals including aluminum, cadmium, copper, iron, manganese, mercury, and zinc. These contaminants appear in surface water, sediment, and soil, particularly along Ore Knob Branch. Copper is present in all three media. The metals can produce acid mine drainage that harms streams. Affected waterways include 1.5 miles of Ore Knob Branch, 2.25 miles of Little Peak Creek, about 2.9 miles of Peak Creek (a stocked trout fishery), and a stretch of the South Fork New River. Contaminated groundwater poses the primary threat to public health.

EPA and the North Carolina Department of Environmental Quality have already taken several cleanup steps. Starting in April 2010, EPA provided bottled drinking water to households with contaminated or potentially contaminated private wells. Between 2010 and 2012, EPA sampled 79 potable water sources and installed or upgraded 15 whole-house treatment systems. In 2011, EPA completed emergency repairs to the Main Tailings Impoundment Area dam, removing 76,000 cubic yards of tailings, re-facing the dam, and building diversion channels to reduce erosion and acid mine drainage. In February 2015, EPA determined that a municipal water line would be extended about 8 miles from Jefferson to affected residents. A groundwater removal action started in September 2015 and is estimated to finish between December 2026 and February 2027.

The site is divided into four operable units (OUs). A final remedy for Operable Unit 02, covering Ore Knob Branch, was selected on September 30, 2024. Cleanup technologies for that unit include excavation, dredging, capping, bioreactive walls, neutralization, and bioremediation, among others. Remedial design for OU 02 is estimated to start in September 2025 and finish between March and May 2027. Physical construction has not yet begun at the site. Current data are insufficient to determine whether human exposure or groundwater migration are under control.

Community members can stay involved through EPA's ongoing outreach efforts, which include public notices, public meetings, and interviews. A virtual public meeting on the Interim Proposed Plan was held on May 14, 2024. Site records are available at the Ashe County Library in West Jefferson, North Carolina. Residents with questions can contact Community Involvement Coordinator Zariah Lewis or Remedial Project Manager Megan Arias.