De Beers Canada has notified the Mackenzie Valley Land and Water Board it intends to file a final closure and reclamation plan for its defunct Snap Lake diamond mine.
"Until that plan is submitted, it is premature to discuss what final closure will look like or what the associated costs will be," said De Beers spokesperson Terry Kruger in an email to CBC.
Snap Lake was De Beers' first diamond mine outside of Africa, according to the company's website. It is located 220 kilometres northeast of Yellowknife.
It opened in 2008 and was expected to produce diamonds for 15 years. In 2014, the mine produced 1.2 million carats of diamonds.
In December 2015, De Beers announced it was closing the mine and laying off 434 workers. The closure came in the wake of a downturn in diamond prices and water problems at the mine that required an amendment to the mine's water licence.