Giant Mine

Year: 2005–Present
Client: Government of Canada, Public Works and Government Services Canada
Project Scope Performed Under: Deton’Cho/Nuna Joint Venture, a partnership with Det’on Cho Corporation (Yellowknives Dene First Nation)

Between 1948 and 2004, the Giant Mine was a major economic driver for Yellowknife and the Northwest Territories. When the mine closed, attention focused on the environmental issues left behind, notably 237,000 tonnes of arsenic trioxide stored in underground chambers. Since 2005, Deton’Cho/Nuna Joint Venture has been under contract with the Government of Canada to provide care and maintenance at the Giant Mine site.

Project Scope

• Maintenance of site facilities, equipment, underground access, and hoisting and pumping equipment
• Site security
• Bulk fuel storage demolition
• Select building demolition
• Pipe works upgrade
• Surface water management improvements
• Operation of the Effluent Treatment Plant

Client: Government of Canada, Public Works and Government Services Canada
Project Scope Performed Under: Deton’Cho / Nuna Joint Venture, a partnership with Det’on Cho Corporation (Yellowknives Dene First Nation)

Under the Giant Mine Care & Maintenance contract with the Government of Canada, Deton’Cho / Nuna Joint Venture provided construction services to support a trial project designed to optimize methods of freezing the underground arsenic storage chambers.

Project Scope

• Surface drilling by a variety of methods (mud rotary, coring, and down hole hammer) and installation of piping for a mechanical freezing system
• Instrumentation installations
• Underground development required for horizontal drilling and freeze pipe installation
• Surface civil works and site grading
• Bulkhead construction