What to expect at the Giant Mine site for the rest of 2026

The director of the Giant Mine Remediation Project says “2026 is going to be a busy year.”

Chris MacInnis made the remark during the federally led project’s annual public forum earlier this month. He said the majority of the project’s “major work packages” are well into construction or heading into the final phases of design or procurement.

Cleanup of the former gold mine on the edge of Yellowknife officially began in 2021 and is expected to take until at least 2038, costing $4.38 billion, before the site goes into perpetual care.

Remediation work completed at the site so far includes deconstruction of the old roaster and former townsite as well as the creation of a non-hazardous waste landfill, cleanup of legacy metal waste and closure of the mine’s underground.

MacInnis said work conducted in 2025 included a structural assessment, soil sampling and bird deterrents for the mill plant. He said the mill was also wrapped to control dust during upcoming work and the mill lab was demolished.

Plans for the project in 2026 include more decontamination and deconstruction work, completion of a new water treatment plant, and improvements to the nearby Highway 4.

This summer, MacInnis said, deconstruction of the remaining big structures on the site is expected to take place. Those include the mill, tailings reprocessing plant and C-dry building.

Once that is complete, he said, about 30 smaller buildings and sheds will remain. Those structures are expected to be demolished in 2027.

“After that, the landscape of the Giant Mine site will look much, much different than you see today,” he said.

MacInnis said construction of a new water treatment plant, which began in 2023, is now 80-percent complete.

Patrick Schmidt, an engineer at the remediation project, said work on the plant this year will focus on finishing remaining internal construction such as heating, ventilation, electrical and process work.

The plant is expected to be fully operational by 2027.

Other work planned for 2026 includes the start of drilling and installation of thermosyphons in an area known as the AR1 freeze pad to freeze underground chambers containing highly toxic arsenic trioxide.

MacInnis said the project hopes to award the contract for that work in late May or early June.

Work on the Ingraham Trail is expected to focus on an effluent treatment plant crossing and access to the Giant Mine site, including the introduction of turning lanes to minimize impacts to traffic. Construction is scheduled to take place between May and October.

MacInnis said that work is intended to help with the volume of trucks that will be hauling material from a quarry across the highway, as well as plans to shift the main access point to the Giant Mine site from its current location, near the Yellowknife Historical Museum, to an area off the highway called the Brock gate.

Trailers near that entrance are set to replace C-Dry as office space for staff.

Beyond construction, remediation project staff are currently developing the first version of a perpetual care plan for continued monitoring and management of the site once remediation is complete.

That will include continued freezing of underground chambers until a permanent solution is found for the 237,000 tonnes of arsenic trioxide stored at the site, as well as treatment of water.

Audit request

One question raised during the remediation project’s annual forum was about the impact a proposed audit could have.

The House of Commons Standing Committee on Indigenous and Northern Affairs passed a motion earlier in February calling for a value-for-money and performance audit of the Giant Mine Remediation Project dating back to 2015.

The request is not binding on the Auditor General of Canada.

The motion was introduced by Bob Zimmer, an MP in northern BC and the Conservative Party’s shadow minister for Arctic affairs, who has raised concerns about the cost of the remediation project.

The project was initially estimated to cost just under $1 billion in 2013. The updated $4.38-billion cost estimate was made public in November 2022.

In an opinion piece published by NNSL in November last year, Zimmer attributed the cost increase to government mismanagement and labelled the project a “Liberal scandal.”

Cabin Radio was unable to secure an interview with Zimmer prior to publication.

Remediation project officials have said the 2013 estimate did not take into account inflation, nor contingency and project management costs.

Natalie Plato, deputy director of the remediation project, told Cabin Radio in 2023 the project has also since expanded to include treatment of water to drinking-water standards for arsenic, filling all open pits, covering tailings, relocating a pond, treating a larger amount of contaminated soil than was originally estimated, and using more borrow material.

The project timeline was also extended by nine years, she said, in part to ensure that northerners have the capacity to bid on and participate in project work.

In a recent statement to Cabin Radio, Crown-Indigenous Relations and Northern Affairs Canada said it “continues to prioritize transparency and the effective management of the project.”

The department said annual reports explain how project decisions are made and how regulatory requirements have “improved safety, environmental protection and opportunities for northern and Indigenous communities.”

The statement added the project is regularly reviewed through audits, evaluations and financial checks, while the Giant Mine Oversight Board provides independent oversight.

Giant Mine ‘must not be a political football’

In a letter responding to Zimmer’s opinion piece, also published by NNSL last November, Alternatives North’s Karen Hamre argued the real scandal was not the cost of the cleanup but how the Giant Mine site became so toxic in the first place.

“Cleaning up Giant Mine is one of the largest and most technically difficult environmental projects in Canada,” she wrote.

“This is not a recent scandal. This is a long-term disregard for the need to properly regulate mining in the North, and to protect our people and the environment.”

Hamre pointed out the 2024 annual report by the Giant Mine Oversight Board states the remediation project remained on budget and largely on schedule save for a delayed draft of an aquatic effects monitoring program and work on the perpetual care plan.

One of the main procurement concerns expressed by the watchdog in that report focused on the potential use of joint ventures to allow non-Indigenous firms to compete for government contracts prioritized for Indigenous-designated companies, or profit unfairly from them.

The oversight board noted that while more Indigenous-designated firms were competing for contracts with the remediation project, that had not been matched by an increase in northern Indigenous employment.

The project contracted Oxaro Inc to conduct an audit of its procurement strategy for Indigenous businesses from 2017 to 2023.

In its report, the watchdog also highlighted concerns with the project’s strategy for achieving employment targets. The board said there was a need to clearly define training hours as reported hours appeared to be misrepresentative of legitimate training.

In her opinion piece, Hamre cautioned against partisanship, saying the project “must not be a political football” but “a shared commitment to doing what is right” for current and future generations.

She called for Giant Mine to be used as a lesson to ensure future large projects are appropriately assessed and regulated.

“I think it should be clear in the context of Giant Mine that less regulation is not a good thing,” she told Cabin Radio.

“If you want a long-term healthy environment and you want good working conditions, you need regulations and you need those regulations to be enforced.”

Correction: March 18, 2026 –11:39 MT. This article initially stated the Giant Mine Oversight Board conducted an audit of the remediation project’s procurement strategy for Indigenous businesses. In fact, the project hired Oxaro Inc to conduct that audit.