De Beers SA said Dec. 15 that it will start flooding the underground workings of its Snap Lake diamond mine in Canada's Northwest Territories in early January 2017 to transition the mine into a long-term phase of care and maintenance, primarily focused on environmental monitoring activities.

The Anglo American Plc subsidiary tried to sell the idled mine in July and tapped Bank of Montreal to help with the transaction. De Beers said it engaged with interested external parties but failed to reach an agreement for the deal.

According to the miner, its extended care and maintenance program for Snap Lake will preserve the long-term viability of the ore body and reduce costs, while also mitigating environmental risks associated with maintaining dormant operations, until market conditions and improved methods make the kimberlite more economic to operate.

De Beers will run a winter road program at the mine in the first quarter of 2017 to remove some inventory and equipment and bring in fuel supplies to the site.

Snap Lake employs 55 people, which will be reduced to about 35 once flooding is complete. The flooding is expected to take up to eight weeks, and displaced employees will receive consideration for an alternative placement at other De Beers facilities or a fair severance package exceeding regulatory requirements.