Cleanup Continues Following Massive Cyanide Spill In Yukon River Tributary

Government of the Yukon officials are now overseeing the cleanup following an equipment failure at a major Yukon Territory gold mine that dumped cyanide into a tributary of the Yukon River Alaska’s largest transboundary waterway.

The spill, which dumped enough cyanide to fill more than 120 Olympic sized swimming pools, is expected to result in long term monitoring of its impact on the environment, Yukon officials said.

The incident at Victoria Gold’s Eagle Mine on June 24 released almost 300,000 cubic meters (10.54 million cubic feet) of cyanide solution into a subtributary of the Stewart Watershed in the Yukon Territory and about 10 days later, high levels of cyanide, which is toxic to salmon and other fish, were detected in a nearby creek.

Alaska Department of Fish and Game Commissioner Doug Vincent-Lang said July 30 that ADF&G is aware of the situation, but that so far there appears to be no threat to salmon in transboundary rivers flowing into Alaska.

“We are concerned and are watching it,” he stated.

The Yukon government has stepped in and is providing updates on Victoria Gold’s Eagle Mine heap leach failure, with frequent reports to ADF&G officials, he said.

The latest report from the Yukon government, on July 26, said that due to the mine company’s failure to construct a safety berm, the government of Yukon has engaged contractors to design and build the berm, which is critical to ensure that groundwater monitoring and interception wells can be installed safely.

Groundwater wells are required to monitor groundwater for potential contamination and to pump potentially contaminated groundwater to surface for treatment and safe discharge.

That work was expected to take about two weeks to complete, and groundwater wells can be installed in certain locations as construction progresses once it is safe to do so, the Yukon government report said. However, a forest fire burning along the access road to the mine site may impede the contractors access to the site, they said.

Staff from the government of Yukon and the First Nation of Nacho Nyak Dun are in regular communication and have developed a joint water quality monitoring plan for on-site and downstream of the mine site, the report said.

Water samples are being screened for various forms of cyanide, heavy metals and other contaminants and are being compared to federal aquatic life water quality guidelines and to the water quality objective as part of the mine’s licenses, according to the report.