Water contained
While Mulligan said not all of the groundwater flowing through the Eagle site is captured, there is no evidence yet that contaminated groundwater is entering Haggart Creek, which flows away from Eagle.
Drinking water is also safe for now, said Yukon’s chief medical officer of health Dr. Sudit Ranade.
“The drinking water system that is regulated is still not at risk and so that is not a concern at this moment,” he said.
Friday’s news briefing dealt only with water sample results and not the ongoing clean up effort at the mine, where the Yukon government was last reported to have hired contractors to build a berm to protect groundwater wells.
Fish kill from discharge
A discharge of water from a treatment plant at Eagle last Friday led to the discovery of 68 dead Arctic grayling and sculpin fish in Haggart Creek, senior fisheries biologist Cameron Sinclair said. Victoria began discharging the water on July 31.
When Victoria discovered the dead fish, it immediately stopped discharging water.
“The dead fish that were observed this week are believed to be due to the discharge from the mine’s water treatment plant and not directly due to the contaminants that we’ve been seeing in the receiving environment,” Sinclair said.
Although the fish kill is an expected outcome of cyanide toxicity, chief veterinary officer Dr. Mary Vanderkop said, the good news is that cyanide doesn’t bioaccumulate. If other wildlife consume those fish, it doesn’t pose a risk to them or to the environment.
Asked if the fish killed was due to something going wrong with the discharge, Department of Energy, Mines and Resources spokesperson Devon Seaman said by email that Victoria had the authority to discharge water if the water was compliant with it’s water licence criteria.
The government also directed Victoria on Tuesday to submit lab results showing its water meets licensed criteria before it can discharge water again, Seaman added. The federal Department of Fisheries and Oceans (DFO) was informed of the fish kill and Victoria was ordered to do mitigation efforts, such as building fish barriers in Haggart Creek, and salvaging fish downstream.
Victoria has frozen and kept the 68 dead fish. Sinclair said DFO and Environment and Climate Change Canada would take the lead in case of a further investigation of the fish deaths. Yukon’s environment department might also pursue its own investigation.
Surface water samples haven’t returned concerning concentrations of heavy metals, but the government has launched a wildlife surveillance program to monitor heavy metals that might have been released into the environment after the Eagle accident, Vanderkop said.
Unlike cyanide, which dissipates quickly when exposed to heat, light and fast-moving water, heavy metals can accumulate over years, she said.
The government is asking hunters in game management zones north of Mayo to collect kits and take tissue and bone samples from animal carcasses and submit them to the government to test for heavy metals.
