Rio Tinto’s Diavik diamond mine moves into commercial production underground

Phase 1 of the A21 underground project is slated to produce an extra 1.4 million carats. Phase 2 is expected to add another 800,000 carats and was approved earlier this year with an additional investment of $17 million.

The construction of the A21 underground mine involved the development of over 1,800 metres of underground tunnels to access the orebody and begin underground production.

Rio said there were no lost time injuries after more than 100,000 labour hours completed over 20 months during the development and construction work.

“The A21 underground operation is positive news for our employees, partners, suppliers and local communities in the Northwest Territories, as it will enable operations to continue through to closure,” Diavik mine chief operating officer of Matt Breen said in the statement.

“Rio Tinto’s decision to proceed with Phase 2 is a testament to the excellent performance of our Diavik team in successfully developing the underground mine beneath the previously mined A21 open pit,” Breen said.

He added that the company is continuing its investment in preparing for the closure and remediation of Diavik mine site, focusing on progressive reclamation activities such as earthworks, site clean-up, and equipment procurement.

Diavik represents one of Canada’s largest diamond mines in terms of volume of rough diamonds, having produced over 144 million carats of rough diamonds since mining began in 2003.