Holden Mine

Holden Mine is an old copper, zinc, and gold mine in the Cascade Mountains of Chelan County, Washington. Mining was active from 1937 to 1957, and when it was shut down the mine waste was left behind. Over decades, rain, snowmelt, and groundwater have carried metals and acidic water into soils, creeks, and sediment downstream. The cleanup is important because about 70 people live at Holden Village and up to 6000 people visit each year. These people may be at risk and the natural environment (creeks, wetlands, fish, forests) is heavily affected.

Ecology is working cooperatively with other government partners including, the Yakama Nation and other sovereign tribal groups, the US Forest Service (USFS) and the Environmental Protection Agency (EPA) towards cleanup of the site. USFS is the lead agency for cleanup. For more information visit the USFS Holden Mine Site webpage. During the late 1980s and early 1990s, the Forest Service reduced erosion of the tailings piles by installing streambank protection, rerouting drainage, and covering the piles with gravel.  This interim action improved site conditions; however, several potential threats to human health and the environment still exist.

The large and complex cleanup of this site has been planned in a phased approach: Phase 1, stabilization and capping the hazardous tailings and waste rock has been completed. Phase 2 is focused on capturing and treating impacted mine drainage, groundwater, and seeps to stop the ongoing release to protect the health of the local residents and surrounding communities.

Holden Mine Proposed Plan

Record of Decision

Holden Mine Record of Decision