Giant Mine Remediation Project

Rank 2022


Image Credit: Government of Canada

Industry Sector: Other

Project Type: Remediation

Project Value: $934 million

Funding Source: Public

Federal Funding: $934 million

Province: Northwest Territories

City / Region: Yellowknife

Estimated End Date of Substantial Completion: 2025

Between 1948 and 2004, Giant Mine was a major economic driver for Yellowknife and the Northwest Territories. Mining operations at the site grew over the years to encompass roughly 900 hectares, including a number of ponds and small lakes. In 1999, the former operator entered receivership and the Government of Canada, and its co-proponent, the Government of Northwest Territories (GNWT) became responsible for the Giant Mine site. Mining operations continued until 2004. When Canada and the GNWT became responsible for the mine, several environmental and site remediation needs were identified, including 237,000 tonnes of arsenic trioxide dust left behind in underground chambers, approximately 16 million tonnes of tailings, open pits, debris, site infrastructure and more. Today, the project’s goals are to: minimize public and worker health and safety risks; minimize the release of contaminants from the site to the surrounding environment; remediate the site in a manner that instills public confidence; and implement a remediation approach that is cost effective and robust over the long term. The City of Yellowknife and the GNWT will decide how to use the site after remediation. However, as part of planning the remediation, the Project engaged the public to see how they envision potential future uses of the site. The project applied for the permit and licence again in 2019, which were approved in 2020. Implementation works began in summer 2021. After meeting the requirements of, and receiving all necessary regulatory approvals, reclamation work on Giant Mine was able to begin in summer 2021. Work in 2021 included: beginning the construction of a landfill to hold non-hazardous waste; underground stabilization preparatory work; geotechnical drilling; ongoing operation and maintenance of the effluent treatment plant; dust control; waste management, including temporary hazardous waste storage; sewage and greywater management; beginning metal recycling; and beginning construction of the first of four freeze pads.

Project Owner: The Government of Canada (led by Crown-Indigenous Relations and Northern Affairs Canada with support from Public Service and Procurement Canada) and the Government of the Northwest Territories (led by the Department of Environment and Natural Resources)

Engineer: AECOM (environmental services, preliminary and detail design); Golder (a member of WSP); Wood (consulting)

Project/Construction Manager: Parsons

Environmental Services: Dillon Consulting ; SLR ; Blumetric

Other Key Players: SRK Consulting; Golder (multi-disciplinary consulting services, general and civil design); Hatch (design); AECOM (environmental services, preliminary and detail design); KPMG (commercial advisor); SRK Consulting, Arcadis Canada Inc. (lead technical advisors); Colliers Project Leaders; McElhanney (surveying services); Englobe

Financing Detail: Aboriginal Affairs and Northern Development Canada (AANDC) requested the Audit and Evaluation Sector (AES) conduct a value-for-money audit of the remediation project to examine the ability of a government organization to discharge its responsibilities and control their costs by ensuring resources are managed economically. In this analysis, total project costs were estimated at $934 million thought 2025. (Beyond 2025, the government estimated there would be $1.98 billion in operations and maintenance costs through 2137.)

2022 Rank: 64

2021 Rank: 55

2020 Rank: 57

2019 Rank: 59

2018 Rank: 57

2017 Rank: 53

2016 Rank: 53

2015 Rank: 54


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