A quick guide to the end of Diavik

The NWT’s Diavik diamond mine expects to stop mining in March 2026. Here’s a simple guide to what happens next.

The details on this page come from a presentation given to Yellowknife City Council by Diavik general manager of closure Gord Stephenson on November 24, 2025.

As of November, Diavik was down to two underground operations focused on the A21 and A154 North kimberlite pipes. (Mining of the A154 South pipe recently closed down.)

“We’ve got about four months left of operations, so it’s definitely bearing down on us,” said Stephenson.

When it closes, Diavik will have completed just over 23 years in operation. Commercial production began in January 2003.

How long will closure last?

Diavik plans to spend from 2026 to 2029 completing closure of the site.

Diavik has been working on closure for years alongside active mining – an approach the mine calls “progressive reclamation.” That means the closure period is set to be much shorter than for some other mines.

By 2029, Diavik expects to start a “post-closure monitoring” period until 2040, after which it hopes to relinquish the land. There probably won’t be an active presence at the site after 2030.

How many people are affected?

Stephenson said about 1,000 people work at the mine right now, meaning 500 or so are on site at any one time. Of those, about a third are northerners. Fourteen percent of people employed are defined by the mine as “northern Indigenous.”

Diavik says 238 employees and 63 contractors are Yellowknife-based.

During a six-month decommissioning period starting in March 2026, staffing will “drop significantly” from 900 to between 200 and 300 people, Stephenson said. From then until 2029, the work will involve 100 to 250 people.

What happens to Diavik’s agreements with communities?

In the NWT, mines generally have agreements with nearby communities or Indigenous governments that contain financial benefits and other obligations.

Diavik calls these “participation agreements” and has signed five of them, with the Tłı̨chǫ Government, Yellowknives Dene First Nation, Kitikmeot Inuit Association, Łútsël K’é Dene First Nation and North Slave Métis Alliance.

“We’re currently in the process of establishing closure agreements with our participation agreement partners,” Stephenson said.

What happens to investment in Yellowknife and the NWT?

“On an annual basis, you see about $285 million through northern businesses and $131 million through northern Indigenous spend,” said Stephenson, setting out Diavik’s yearly spending. That will leave a large economic hole when it disappears.

The mine’s head office in Yellowknife will remain open throughout the closure process until 2029. After that, Stephenson said, “we’ll evaluate requirements.”

He noted Diavik has contributed several hundred thousand dollars to a new fund designed to outlive the mine and help support local events into the future.

What are the environmental issues?

Indigenous nations have expressed concern about issues like water quality and the health of fish as the mine closes, as well as calling for the inclusion of traditional knowledge in monitoring.

Stephenson said Diavik is working to include traditional knowledge.

He stressed to councillors that diamond mining relies on gravity, pressure and water to extract diamonds. “There’s certainly no arsenic or cyanide use, which is one of the questions we often get,” he said.

More broadly, Diavik has sought to contrast itself with the likes of Giant Mine, the former gold mine that closed abruptly in the early 2000s and left behind a highly toxic site that now requires a $4-billion federal cleanup.

“We hope that the Diavik story is one that could inspire further investment in the mining industry in the Territories, and that it will be a positive chapter in terms of how a mine can be successfully operated and then closed and then eventually relinquished,” Stephenson said.