De Beers prepares for final closure of defunct Snap Lake diamond mine

De Beers Canada has notified the Mackenzie Valley Land and Water Board it intends to file a final closure and reclamation plan for itsdefunctSnap Lake diamond mine.

On Dec. 14, the company requested to forego filing an interim closure plan something that would have essentially extended care and maintenance at the site in favour of filing a final closure plan in 2019.

• De Beers puts shuttered Snap Lake diamond mine up for sale

"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.

According to documents filed with the Mackenzie Valley Land and Water Board last year, the N.W.T. government holds just under $40 million in reclamation security for the Snap Lake mine.

Kruger said there is a 12-person team employed to do care and maintenance at the mine, but the number of onsite employees at any given time fluctuates depending on the time of year and work required.

Frame Lake MLA Kevin O'Reilly says it's about time for somebody at De Beers to make the decision to pull the plug on Snap Lake and explained how the cleanup process would work from there.

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"There needs to be a sort of an overall set of closure objectives for each of the parts of the mines and measurable criteria," he said. "So somebody can say, 'Yes you've met this, you've covered the site with two metres of crushed rock or you re-vegetated this part of the mine site with these species covering hectares,' or whatever."

O'Reilly said he'll be keeping a close eye on the clean up, as the mine site is located on Snap Lake and in the path of the beleaguered Bathurstcaribou herd.

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A 'troubled' operation from the beginning

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.

At the time, De Beers Canada CEO Kim Truter described Snap Lake mine as a "troubled operation" since it opened.

The plan was to mothball the mine under a care and maintenance plan and wait for a possible market rejuvenation or a buyer to come forward. Neither happened and in 2016the company decided to flood the underground portions of the mine.

• De Beers gets the OK to flood underground Snap Lake mine