Giant Mine Roaster Complex Decontamination and Deconstruction Project – Yellowknife, NT, Canada

Environmental Protection

The Giant Mine Roaster Complex Deconstruction project was the first major project undertaken in the overall cleanup of a large, abandoned gold mine on the edge of Great Slave Lake within the Yellowknife city limits, about 250 miles south of the Arctic Circle. The mine operated from 1948 to 2004 under a series of owners and became the responsibility of the Canadian Federal Government for its cleanup.

Public Works and Government Services Canada (PWGSC) hired Parsons on behalf of Aboriginal Affairs and Northern Development Canada (AANDC) to decontaminate and deconstruct the 10 major structures at the Roaster Complex, which at the time were Canada’s most contaminated buildings. At project inception, the Roaster complex’s buildings and other structures were in various states of disrepair and contained large amounts of arsenic trioxide (a byproduct of the mine’s ore roasting process) and asbestos. Our scope of work included:

• Handling/storage of arsenic trioxide contaminated waste and asbestos
• Project planning/permitting
• Decontamination
• Hazardous waste abatement and removal
• Deconstruction
• Construction management

We successfully removed more than 10,000 tons of highly toxic arsenic trioxide from the Roaster complex through a design-build contract by providing comprehensive construction management services to decontaminate and deconstruct the 10 aboveground structures to slab-on-grade standard while at the same time safely protecting workers and the public

To keep the arsenic trioxide and asbestos from escaping and potentially creating hazardous conditions in the community, we first sealed each building. Negative air machines pulled air in, and exhaust was vented through high-efficiency particulate air (HEPA) filters to remove all contaminants. The buildings were decontaminated within the containment system, and all remaining building components were then sprayed with a glue sealant. After the arsenic trioxide and asbestos-containing materials were removed and all internal building surfaces are decontaminated and sealed, the containment systems, including the shrink wrap and scaffolding, were disassembled and the final building deconstruction then took place.

By completing the decontamination and deconstruction of the Giant Mine Roaster Complex, the once unstable and highly contaminated area was made safe until the full-scale, decade-long remediation efforts began for the rest of the contaminated mine site.

Featured Mar 2014/Updated Aug 2017