The Diavik Diamond Mine lays on the Lac de Gras lake, in Canadian Northern Territories. About 200 kilometers south of the Arctic Circle, besides the diamonds, the bottom of Lac de Gras represents one of the most important and dedicated ecosystems in the world as well as indigenous ancient territories  .
Diavik comprises four diamond-bearing pipes that are mined using a combination of open pit and underground mining. The mine is managed by Rio Tinto and is owned by a joint venture between Diavik Diamond Mines (2012) Inc., a wholly-owned subsidiary of Rio Tinto (60% ownership) and Dominion Diamond Diavik Limited Partnership, a wholly-owned subsidiary of Dominion Diamond Mines (40% ownership) .
The mine was approved in 1999 and opened in 2003 . In 2018, a fourth diamond pipe was opened. The new open pit pipe contributed to an important incremental extraction of the mine . There are three of the most precious diamonds that the companies exploit from the mine, and collectively known as "The Diavik Stars of the Arctic". However, the most valued and the rarest diamond on the market is their Large Yellow Diamond, with the mine on average producing only five of these diamonds each year but earning the highest profit from .
However today, the company filed for an amendment to its water license with the Wek'eezhii Land and Water Board last year that would allow it to fill three mined-out pits with processed kimberlite — diamond-bearing rock — which includes waste rock and tailings known as slimes. At the moment, processed kimberlite is piled into a containment facility in the middle of the island where the mine operates .
Argumentation for such a devastating environmental project, the Diavik says is due to storage area shortage which won't last until the mine is set to close in 2025" .
First Nations communities are not happy about the decision and are still calling for a full-panel environmental assessment of the mine. Leaders such as Chief Felix Lockhart of the Lutsel K'e Dene, say the environment minister has ignored the concerns of First Nations people and acted irresponsibly. "We're also talking about future mining endeavours upcoming" .
The Mackenzie Valley Environmental Impact Review Board conducted an environmental assessment of the proposed plan, saying more information is needed on how adding mine waste to the pits could affect fish, wildlife and traditional use by Tlicho and Akaitcho Dene . "It's different from what was originally planned in 1999. You have to get the new thing considered as carefully as the first thing" .
First Nations representatives, the federal and territorial governments and Diavik will jointly determine the scope of the environmental assessment because the First Nation's concern was raised that the processed kimberlite could contaminate water in Lac de Gras when the dikes are breached. "Much more information is needed to prove the scientific modeling is sound" .
"Their proposal is that they will deposit all of the processed kimberlite into the underground and they will fill it up with water — they say it will never mix, or flip" ..."Then for five years after active closure, they're going to monitor that water inside the dike and after five years if they determine that water is safe, they'll breach the dike and it'll become a greater part of Lac de Gras" .
First Nations are still concerned, "A lot of what they're proposing relies on permafrost being there, and with climate change, the permafrost isn't going to be there anymore .
An alternative proposal by the company is to store the processed kimberlite by raising the dam walls of the existing processed kimberlite containment facility and building additional on‐land containment sites. It is to say, to expand the areas where the waste will be placed .
The Mackenzie Valley Environmental Review Board opened the opinion for the public hearing, in which Crown-Indigenous Relations and Northern Affairs Canada provided $300,000 to individuals and groups to help them to participate in the environmental assessment .
The report was completed in 8 months, and, unfortunately, on January 6, 2020, the project was approved by the Board :
"The Review Board recommends the Project to be approved subject to implementation of the measures described in the Report of Environmental Assessment. These measures are necessary to prevent significant adverse impacts on the environment :
To ensure that water in the pit lake(s) meets new water quality objectives, it is important to: collaboratively develop criteria for judging if water will be good for cultural use; Update its water quality modeling; Establish an independent review panel to improve updated modeling; Conduct additional and more effective engagement with potentially affected Indigenous communities.
The Review Board believes this concern is reflective of the real and important impacts that this project might have a pressing issue that was discussed during the environmental assessment, about the drastic decline of the Bathurst caribou herd. The Review Board believes the Project will not lead to impacts on caribou, and therefore will not contribute to the decline .