What's happening at Giant Mine? July to September 2021

Underground Stabilization

This year work began on drilling the holes that will deliver the backfill material to the remaining underground voids that need to be filled as part of the Closure and Reclamation Plan.

Work also continues underground to make sure the tunnels are safe for workers to construct barricades that will contain the backfill material. The backfill will be made from existing mine waste (tailings) mixed with water and cement.

Once delivery of the backfill material starts, we expect the process will continue during the summer months until the near surface voids are stabilized. The project team anticipates completing the stabilization work in 2024.

Construction of the AR1 freeze pad

Construction of the AR1 freeze pad will begin in fall 2021, the first freeze pad the project will construct. Freeze pads are required to install the thermosyphons to freeze the arsenic trioxide in place. To begin construction, the project needs to first flatten the area, which is done by blasting. Blasting will begin in late September 2021 and take approximately 10 weeks to complete. More information is included in the project’s blasting notice.

The project also expects to complete additional construction work on the AR1 freeze pad in 2022. To receive more information on the project, including notifications regarding activities such as blasting, please email the project team and ask to be added to our distribution list.

Aquatics Advisory Committee update

The Giant Mine Remediation Project has continued its engagement with respect to the aquatic environment throughout the spring and summer months. In early May 2021, the Aquatics Advisory Committee met to discuss the construction of the AR1 freeze pad. Because the construction of the AR1 freeze pad is located in close proximity to Baker Creek and requires blasting to begin, the project team included this discussion as part of the aquatic environment engagement.

The committee made recommendations to help the project team plan construction work that minimizes impacts to the fish in Baker Creek. Including planning work that will take place in late fall and early winter of 2021, after most, if not all fish have migrated out of the creek. The project team will arrange to have any remaining fish removed and relocated outside of the blasting radius before work begins. The project team will also put other controls in place, such as blasting mats used to contain the blast and prevent flying rocks, minimizing the potential for blasted rock to enter the creek.

In late June 2021, the committee met to discuss the project’s work on its Fisheries and Oceans Canada fisheries authorization, and the Yellowknife Bay fish and fish habitat. Projects with the potential to harm fish or fish habitats need authorization from Fisheries and Oceans, under the Fisheries Act, before work can begin. Committee members helped provide local and traditional knowledge about the species of fish normally found in the area. The project team will use this information to inform the fish species calculations required for the fisheries authorization. These calculations determine how much fish habitat the project will need to replace or move, in compliance with the project’s authorization. The next committee meeting is scheduled for late August 2021 to discuss the types of monitoring the project requires in Yellowknife Bay during remediation.

Domestic waste disposal

Parsons awarded a new contract to dispose of ordinary, day-to-day garbage to Northern company Kavanaugh Bros.
Contract duration: June 24, 2021 to September 31, 2022
Contract value: $291,160.

Off-site borrow

Parsons issued the off-site borrow work package as a standing offer agreement. A standing offer agreement allows Parsons to issue standing offers to more than 1 company to call upon and fill orders, which in this case includes providing borrow material or fine gravel or rock fill to the site, for the project’s early works. The standing offer has been issued to 2 Northern companies: CJ Contracting and Ace Enterprises Ltd.
Contract duration: June 30, 2021 to September 30, 2021
Contract value: $7,480,000.

Tailings dust suppressant

Parsons awarded the contract to provide SoilTac, the approved dust suppressant for the site, to a Northern company ALX Exploration Services.
Contract duration: May 1, 2021 to March 31, 2022
Contract value: $273,520.

Northwest Pump electrical commissioning

Parsons awarded the contract to conduct electrical work on the Northwest Pumps, which maintains the water level underground, to Purcee Electric.
Contract duration: finite work,
Contract value: $53,230.

Northwest Pump 201 replacement

Parsons awarded the contract to replace Northwest Pump 201, which is one of the pumps that maintains the water level underground, to Baker Hughes Canada Company.
Contract duration: finite work
Contract value: $31,750.

Early works backfilling

Using a competitive tender process under the Procurement Strategy for Aboriginal Business, Parsons awarded the new contract to backfill portions of the underground to ensure their stability to Nahanni Construction.
Contract duration: anticipated start fall 2021 to September 30, 2022.
Contract value: $38,380,534.

Part of the Nahanni Construction's bid included commitments to Indigenous opportunities considerations. These included:

• 2160 hours of training for Indigenous staff
• 76% of labour to be carried out by Indigenous staff
• 72% of the subcontracting funds to be allocated to Indigenous companies

Freeze pad construction

Using a competitive tender process under the Procurement Strategy for Aboriginal Business, Parsons awarded the contract to construct 1 of 4 freeze pads on the site to DJRM First Nations Construction Corporation.
Contract duration: July 23, 2021 to July 28, 2022
Contract value: $5,896,819.00.

Part of DJRM First Nations Construction Corporation's bid included commitments to Indigenous opportunities considerations. These included:

• 1280 hours of training for Indigenous staff
• 72% of labour to be carried out by Indigenous staff
• 63.2% of the subcontracting funds to be allocated to Indigenous companies