Holden Mine Site Cleanup

Holden Mine is an inactive underground mine located along Railroad Creek 10 miles west of Lake Chelan.

The Washington Department of Ecology is studying Railroad Creek over the long term to assess aquatic life uses at the Holden mine site.

Railroad Creek Monitoring Study and Results

Railroad Creek monitoring site screenshot


Holden Mine Site - First 5 Year Review Report
[PDF: 3.4 mb]

Deep in the heart of the Forest above Lake Chelan, a dramatic sight unfolded between 2013 and 2018 as dozens of bulldozers, graders, loaders, and excavators worked to reshape a rock-strewn mountain side. The ground rumbles as giant dump trucks drive past, hauling yet another load of mine waste tailings across the 90-acre site. A giant crane hums as it pours more concrete for a footing. These are the sights and sounds of progress as hour by hour, day by day, the once toxic landscape of Holden Mine is restored. 

“For the first time in nearly 60 years, clean water is once again flowing in Railroad Creek,” said Chelan District Ranger, Kari Grover Wier. “This is an important milestone and a significant win for aquatic species, wildlife species, and humans that depend on water from Railroad Creek and Lake Chelan.” 

Abandoned in 1957, the Holden Mine contaminated groundwater with five toxic metals including aluminum, cadmium, copper, iron and zinc. These heavy metals washed downstream, polluting water in Railroad Creek, a major tributary to Lake Chelan. The metals also created a hazardous, hard orange coating known as ferricrete on the streambed. Unstable waste rock and tailings piles from approximately 10 million tons of mined ore further compounded the problem. 

“The Holden Mine Remediation project is a big benefit to the residents of Chelan County. Not only is the contamination from the mine controlled for future generations, but this project also brought hundreds of jobs to local communities and revenue to the County through employment with Rio Tinto and their contractors.” said Mike Steele, District 12 State Representative and Chelan County resident. “Today, we celebrate with the Forest Service, Holden Village, Yakama Nation, Department of Ecology, Rio Tinto and all those who have worked hard to heal this landscape.” 

Key Project Accomplishments:

  • A 30 to 90 foot deep concrete barrier wall has been constructed between toxic tailings piles and Railroad Creek containing any future runoff.
  • An estimated $240 million dollars of economic contribution were delivered in Chelan and Douglas counties as personnel, lumber, fuel, and numerous other materials and equipment were locally sourced in nearby communities.
  • Thousands of gallons of contaminated groundwater are treaded daily through an on-site treatment plant. 
  • Approximately nine million tons of tailings and 250,000 tons of waste rock piles were re-shaped and stabilized. 
  • During 2017 crews will plant native trees and shrubs atop former waste rock and tailings piles as well as work on an interpretive trail for the site. 
  • No tax-payer funds have been used to complete this work. Remediation costs have been paid exclusively by Rio Tinto, a global mining company which inherited the responsibility for the cleanup from the Responsible Party, Intalco.
  • In 2017, Holden Village will resume guest services and programming.

“This project is a testament to commitment, and partnerships, through government and private entities,” added Grover Wier. “Five years later and a nearly 500 million dollar investment by Rio Tinto, a legacy of contamination has been turned into a legacy of clean water.”

Partners and stakeholders in this project include Rio Tinto, Holden Village, the Yakama Nation, Washington Department of Ecology and the Environmental Protection Agency. The U.S. Forest Service is the lead agency overseeing the remediation efforts, as the majority of the cleanup is on National Forest lands. For a full video of site efforts, please see www.holdenminecleanup.com. The complete Record of Decision is also available for download. 


Railroad Creek Monitoring Study and Results

Holden Mine Site - First 5 Year Review Report

Aerial View of Holden Mine Area

History: Between 1938 and 1957, the Howe Sound Mining Company mined copper, zinc, gold and silver from the Holden Mine.  300,000 cubic yards of waste rock and about 8.5 million tons of mine tailings covering about 90 acres were left at the site. Since mining operations ceased, the mine partially filled with water.  This water becomes contaminated as acid mine drainage that drains into Railroad Creek at concentrations toxic to aquatic life.

Rio Tinto: Rio Tinto, a global mining company,  is managing the cleanup on behalf of Intalco and is paying for the entire cleanup.  Rio Tinto never owned or operated the Holden Mine; but, through a series of company acquisitions and legal transactions Rio Tinto has an arrangement to manage this cleanup.

Holden Village: www.holdenvillage.org