Despite wildfires burning near Yellowknife, the enormous volume of deadly arsenic trioxide stored at Giant Mine poses “low risk,” according to the federal government.
There are 237,000 tonnes of arsenic trioxide dust at the site, mostly stored in underground chambers.
“Much of the remaining material on the surface is stored in drums located away from vegetation and is also considered low-risk,” stated the Giant Mine Remediation Project, which falls under Crown-Indigenous Relations and Northern Affairs Canada.
“The project team would like to assure the public that a site crew began work prior to the (evacuation) order, to prepare Giant Mine for total shutdown,” the government advised.
Evacuation preparations included collecting brush and clearing materials from recent construction and moving those materials to the tailings ponds and away from structures. Additionally, materials from the previous deconstruction of the roaster are stored inside locked shipping containers in the central tailings pond, away from vegetation, the government stated.
Power was disconnected at Giant Mine, except to three underground pumps.
“The manager of Giant Mine confirmed their comfort with the state of the site prior to leaving following the issuance of the evacuation order out of Yellowknife,” according to the government.
This third season of remediation work began on site in June. The work on the agenda for 2023 includes construction of a new water treatment plant, demolishing the old townsite, non-hazardous waste landfill operations, arsenic sample drilling, investigative drilling, early works paste backfill and effluent treatment plant operations.
READ MORE: ‘Ghost town’: Thousands continue to flee Yellowknife as wildfires loom