Energy, Mines, and Resources
Assessment and Abandoned Mines
Abandoned Mines
Fast Facts
Mount Nansen Pages...
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What was mined at Mount Nansen?
Gold and silver were mined at Mount Nansen.
Where is the mine located?
The mine is located 60 km west of Carmacks and 180 km north of Whitehorse, Yukon, and is within the Little Salmon/Carmacks First Nation (LSCFN) traditional territory.
When did the mine operate?
Since 1943, there has been intermittent gold and silver exploration and mining in the Mount Nansen area. A mill was constructed in the mid-1960s and ore from the Huestis and Webber veins was mined underground. Two attempts at production were undertaken for seven months between 1968 - 1969 and again between 1975 - 1976. Neither attempt was profitable nor produced sufficient amount of gold or silver.
BYG Natural Resources Inc. (BYG) was part or whole owner of the property from 1985 to 1999. The company and various partners began exploration of the Brown-McDade mineral vein system in 1985. A mine and mill operated intermittently for four years until the company failed to meet its water licence obligations in 1999. On February 17, 1999, BYG shut down operations and went into voluntary receivership.
What were the concerns at the mine site when the government took over?
When the site was abandoned, the tailings pond contained high levels of cyanide and metals and was in danger of spilling over the dam into the Dome Creek–Victoria Creek–Nisling River system. The dam holding back the tailings and contaminated water leaked and was unstable. This posed a threat to the downstream environment including vegetation, wildlife and fish.
The original 1940s and 1960s buildings, including the mill and the physical hazards such as pits, trenches and underground workings (called adits) posed safety hazards and needed to be addressed.
What is in place to ensure protection of the environment and public safety at the mine site?
Since the government took over the site in 1999, the water level behind the dam is reduced, relieving some of the concern with dam strength. Some structural improvements were made to the dam and regular inspections occur. Some structural improvements have been made to the dam and ongoing inspections are done.
Water quality is greatly improved through treatment and natural processes to reduce levels of cyanide and metals and to meet safe standards.
Hazardous chemical removal, adit remediation and water treatment are completed at the mine site. Some storage containers of hazardous chemicals left by the company were safely removed and disposed at proper facilities.
The focus of the government is to maintain the environmental integrity of the site. Dam stability, water quality and site security are closely monitored to ensure there are no adverse effects until final closure is completed.
How is the site currently managed?
Government of Yukon (Yukon) manages the mine site with funding from Government of Canada (Canada). Yukon is responsible for continued care and maintenance, along with managing and planning for final closure.
In 2004, the Supreme Court of Yukon appointed PricewaterhouseCoopers as interim receiver responsible for the assets left at the mine site. In 2006, PricewaterhouseCoopers was also appointed trustee in charge of bankruptcy. Peripheral claims were sold, while the core claims the area near the mine site, were held. The core area claims were also held so remediation could be completed.
Over a seven-year period, scientific and engineering investigations were conducted to gain a better understanding of the environmental state of the mine site and surrounding environment. This information will be used to support the final closure and remediation plan for the site.
What is happening at the Mount Nansen mine site?
Yukon continues to manage ongoing care and maintenance at the site and continues to work with Canada and LSCFN to develop a final closure and remediation plan that will address the historical environmental liabilities.
In addition, there is year round onsite security present at the site. Infrastructure maintenance and water quality monitoring are conducted regularly. The monitoring is conducted to ensure the water quality in the tailings pond water, seepages and Dome creek meets safe standards and ensures no discharge of harmful matter is released from these water sources to surrounding waterways.
Security, infrastructure and water monitoring is being carried out by Yukon businesses.
What is the future plan for this site?
Yukon together with the LSCFN and Canada are working towards a final closure and remediation plan to be submitted through the Yukon Environmental and Socioeconomic Assessment Act (YESAA) process.
A technical working group involving Canada, Yukon and LSCFN is established and discussing technical andscientific results that will be implemented into the final closure and remediation plan.
What is next for Mount Nansen?
- Based on the technical and scientific studies conducted to date, the various options for closure and remediation will be reviewed and a final plan will be developed;
- Information gathered from technical and scientific studies will be used to support submission of the final closure and remediation plan into YESAA process; and,
- Community meetings will be held to provide information about the final closure and remediation plan.
Contact Us:
Assessment and Abandoned Mines
Mail: Box 2703, Whitehorse, Yukon Y1A 2C6
Phone: 867.393.7098
Fax: 867.456.6780
Email: yukonabandonedmines@gov.yk.ca
