Brucejack gold mine reaches full stride

Pretium Resources Inc. July 9 reported that its Brucejack Mine produced 111,340 ounces of gold during the second quarter, a quarterly record that puts the northwest British Columbia on pace to produce around 400,000 oz of gold this year.

"With more than 187,000 oz produced in the first half of 2018, we have delivered on our first half 2018 guidance of 150,000 to 200,000 oz of gold," said Pretium President and CEO Joseph Ovsenek.

Pretium achieved commercial production at Brucejack in mid-2017 and the operation produced 228,173 oz of gold during the first nine months of operation.

While the mill outperformed its 2,700-metric-ton-per-day capacity, the gold grades being fed into it were lower than expected.

To rectify this, Pretium implemented a grade-control program to optimize stope shapes resulting in reduced dilution and optimized grade to the mill. This program has improved short-term grade prediction with drilling, sampling and local modelling.

The success of this work is reflected in Brucejack's second quarter production numbers. The 111,340 oz produced during the quarter was from 236,990 metric tons (2,604 metric tons per day) of ore milled that averaged 14.9 grams per metric ton gold.

"The successful integration of our grade -control program into our mining process has resulted in increased grade to the mill with production exceeding grade control estimates for the quarter," said Ovsenek.

A reverse circulation drill introduced as part of a trial program to improve the efficiency and productivity of infill drilling has now been demobilized as it did not deliver the expected cost savings or productivity gains. Going forward, the infill drill program will be carried out with diamond drills.

To improve access and build stope inventory, the rate of underground development has been increased to 700 meters per month, up from 420 meters originally envisioned in the feasibility study for Brucejack.

The company plans to have 10 to 12 stopes with a range of grades available during the third quarter. The increased stope inventory will improve the management of production grades.

"Brucejack has now achieved steady-state production, and we expect to deliver 200,000 to 220,000 oz of gold for the second half of 2018," Ovsenek said.

As a result, Brucejack is on-pace to produce 387,000 to 407,000 oz of gold this year.

–SHANE LASLEY