Glencore digs deeper in sudbury basin: miner pondering new technologies.

• Author: Migneault, Jonathan

The future of Glencore's nickel operations in Sudbury will require deeper mines to access previously untapped deposits, said Marc Boissonneault, the company's vice-president of Sudbury nickel operations.

Boissonneault, who addressed the Greater Sudbury Chamber of Commerce on Oct. 21, said the mining giant is eyeing two potential Sudbury developments that would require mine shafts as deep as 2,700 metres.

The first project is Onaping Mine, a site that was discovered years ago. but contains ultra-deep deposits that could not be safely accessed until recently.

Glencore estimates the mine contains 15.7 million tonnes of nickel deposits at higher grades than average for the Sudbury Basin, and would require a capital expenditure of $547 million to develop.

The company is expected to complete a pre-feasibility study for the project later in the year, and will decide by the first or second quarter next year whether it would be worthwhile to mine the deep deposits.

"Given our life-of-mine situation, we would like to get started on it soon," Bois-sonneault said.

Glencore's flagship mine in Sudbury, Nickel Rim, has a mine life that should extend until 2020, he said.

Glencore is currently exploring a second deposit near Nickel Rim--about 1,000 metres deeper than the current mine--which extends to around 1.700 metres underground.

"We see it as the likely future of Nickel Rim," Boissonneault said.

If the deposit proves to be feasible, along with Onap-ing. it could extend Glencore's Sudbury nickel production until the mid-2030s.

At 2.700 metres. both projects would qualify as ultra-deep mines, and would pose a number of technical challenges.

"Deep mining will require geo-technical management that is a lot more modern," Boisson-neault said. "Geo-technically, what happens is that the stress increases at depth."

One challenge is cooling mine shafts at those depths, which get warmer with every added metre underground.

Boissonneault said Glencore has explored using cold lake water to cool the mines, instead of the more expensive refrigeration systems used in a typical mine.

Parts of Toronto draw in cool water from Lake Ontario to cool buildings near the waterfront. Boissonneault said Glen core could use a similar system for Onap-ing and Nickel Rim.

In January the Sudbury-based Centre for Excellence in Mining Innovation (CE-MI) received a $15-million grant from the federal government's Business-led Networks of Centres of Excellence program to pursue research to...