State environmental regulators have proposed new rules to protect the water quality in Lake Koocanusa and the Kootenai River, which span the international border and have registered a steady increase in a toxic pollutant leaching downstream from Canadian coal mines and into Montana’s prized lakes and rivers.
The proposed rules are nearly four times more stringent than current federal regulations and more than six times more stringent than state regulations.
The Montana Board of Environmental Review initiated a formal rulemaking process to establish site-specific water quality standards for a pollutant called selenium in Lake Koocanusa and the Kootenai River. The decision follows a request made by the Montana Department of Environmental Quality (DEQ).
Selenium is a micronutrient essential to biological functions in animals and certain plants at small quantities; however, at elevated levels, selenium can adversely impact a broad range of aquatic life including fish, and birds that eat aquatic life. High selenium levels can cause reproductive defects, reduced growth and mortality in fish populations.
The rising levels of selenium entering Lake Koocanusa have been identified as a result of historic and current coal mining in the Elk Valley in British Columbia. There are currently no mines with a permit to discharge in Montana that contribute selenium to Lake Koocanusa or the Kootenai River. DEQ listed Lake Koocanusa as threatened for selenium in 2012 due entirely to Canada’s mines.
According to DEQ, the state has worked closely with the British Columbia Ministry of the Environment and Climate Change Strategy, local tribes, industry, federal representatives and state representatives to develop a site-specific selenium standard for Lake Koocanusa. The goal for both Montana and British Columbia is to adopt similar standards that protect aquatic life.
The current selenium standard for the water bodies was established in 1987 at 5 micrograms per liter. In 2016, the EPA developed updated recommended national criteria at a value of 1.5 micrograms per liter for lakes and reservoirs and 3.1 micrograms per liter for rivers, while also suggesting to use site-specific standards, whenever possible.
In Montana, the DEQ opted to pursue a site-specific standard for Lake Koocanusa and the Kootenai River, with the Board of Environmental Review proposing a standard of 0.8 micrograms per liter.
“This standard was developed based on the unique, site-specific aquatic ecosystem of the water body,” according to the record of decision by DEQ.
The proposed standard for the Kootenai River is 3.1 micrograms per liter and is based on EPA’s recommended national criteria.
“The proposed water column value for Lake Koocanusa is lower than the EPA’s national recommended criteria of 1.5 micrograms per liter for lakes and reservoirs, but in alignment with the recommendation that, where possible, selenium standards should be established based on site-specific conditions,” according to the DEQ. “This is because selenium accumulates as it moves through the food chain in bugs, fish and other aquatic life.”
The proposed standards are a culmination of more than six years of collaboration with leading selenium scientific experts and the Lake Koocanusa Monitoring and Research Working Group that included years of public meetings, data collection and a peer-reviewed modeling report.
The next step in the rule-making process is to file a notice of proposed rulemaking in the Montana Administrative Register, after which there will be a 45-day public comment period and a public hearing to be held in early November.