Lake Koocanusa Selenium

A Coal Mining Issue

The Elk River Valley, British Columbia is the site of expansive metallurgical coal mining operations. The historic and present day open-pit mining operations result in vast waste rock piles that have been found to leach contaminants into the Elk River, Lake Koocanusa, and the downstream Kootenai River. Selenium is a contaminant that has been detected at elevated levels as a result of mining operations. 

Why is elevated selenium an environmental concern? 

  • Increased selenium in water can detrimentally impact the reproductive success of fish, and may have associated impacts on wildlife.  
  • Current selenium levels in Lake Koocanusa are below levels that are thought to pose risk to human health. 
  • Current selenium levels in Lake Koocanusa are below the EPA recommended guideline of 1.5 µg/l, but trends over the past decade have increased suggesting the need for active measures to slow or reverse the trend.  

How is the KRN involved in this issue? 

  • The KRN has hosted several public forums over the years to raise public knowledge about the environmental concern of elevated selenium and what is being done about it.
  • The most recent public meetings were held in Libby and Eureka in November 2019.  The public forum included an opening presentation by Montana Department of Environmental Quality (DEQ) describing the current selenium trends, recent developments, and a question and answer session which included representatives from Montana DEQ, U.S. Environmental Protection Agency (EPA), Confederated and Salish Kootenai Tribes, British Columbia Ministry of Environment and Climate Change Strategy (BC ENV), and Teck Resources Limited.   

What are the water treatment efforts to reduce selenium?  

Teck Resources developed a water quality plan to manage selenium and other contaminants that result from coal mining operations located in the Elk River Valley.  This plan was approved by the British Columbia Ministries of the Environment in November 2014, and can be accessed here.  The first tank-based water treatment facility was built at the Line Creek facility.  Technical difficulties with the Line Creek facility caused a temporary shutdown from November 2017 to October 2018.  Teck Resources released an update to the water quality plan in September 2019 that outlines a new type of water treatment using Saturated Rock Fills (SRF). The updated water quality plan provides an updated water treatment facility implementation schedule for both types of water treatment facilities, and can be accessed here

How is MT DEQ and BC ENV addressing the issue? 

Montana DEQ and British Columbia ENV established the Lake Koocanusa Monitoring and Research Working Group to study, understand, and address current and future water-quality concerns in Lake Koocanusa. This working group is comprised of a diverse group of stakeholders. 

A selenium technical subcommittee was formed out of the larger Lake Koocanusa Monitoring and Research Working Group to work towards joint solutions for managing selenium contamination including the development of protective science-based water quality criteria for Lake Koocanusa. Development of the joint water quality criteria is currently ongoing, but is expected to be finalized in 2020. 

The EPA published a selenium criterion  to protect freshwater aquatic life in July 2016.  In this document, EPA recommends the development of a site-specific selenium criteria whenever possible. This is because of the unique way selenium moves through the ecosystem depends on local environmental conditions. 

The Montana Department of Environmental Quality hosts a Wiki site to house information on the research being conducted on the reservoir, progress of technical committees, and letters of commitment between MT DEQ and BC ENV.  Presentations, reports, meeting agendas, and datasets can be accessed at the Wiki site.   

Investigations Further Downstream 

Until recently, most of the focus of selenium research and monitoring has occurred upstream of Libby Dam.  This changed in 2018 when the U.S. Environmental Protection Agency and the U.S. Geological Survey lead a collaborative effort involving the states of Montana, Idaho and the Kootenai Tribe of Idaho to investigate Kootenai River water quality and fish tissue contaminants in Montana and Idaho downstream of Libby Dam. The US EPA summarized the results of this study in a press release that showed that selenium concentrations in water were elevated, but did not exceed the EPA recommended criteria for flowing water.  Selenium was not detected in water samples from Kootenai River tributaries, indicating that the source is the discharge of mine-related constituents from Lake Koocanusa. The study also evaluated selenium levels in 142 fish and found that mountain whitefish eggs in six of the eight samples collected exceeded EPA’s recommended criterion of 15.1 ug/L, the level at which fish reproduction may be harmed. This study indicates that the pollution resulting from upstream mining in British Columbia is not confined to Lake Koocanusa and highlights the need for continued monitoring to ensure that downstream communities and tribes have good water quality capable of supporting healthy fisheries.

KRN’s Commitment 

The Kootenai River Network will continue to track this important issue, and facilitate public education and awareness through updates to this web page and other communications.