Brucejack's 525,000 oz/yr gold mine plan
Last updated 4/12/2019 at 5:35am
Pretium Resources Inc. April 4 said the Brucejack Mine in is now expected to average 525,000 ounces of gold annually over the next 10 years at all-in sustaining cost of US$535 per ounce, according to a new mine plan for the underground mine in northwestern British Columbia.
The new 14-year plan for Brucejack is based on 16 million metric tons of reserves averaging 12.6 grams per metric ton (6.4 million ounces) gold and 59.3 g/t (30.5 million oz) silver.
To push gold production above half a million oz per year, the company is ramping up mill throughput from 2,700 to 3,800 metric tons per day.
Pretium said modifications and upgrades required to sustainably process ore at this higher rate are on schedule and will continue to be implemented during regularly scheduled shut-downs this year.
With these upgrades, the Brucejack Mine is on pace to produce 390,000 to 420,000 oz of gold this year and top 500,000 oz in 2020.
"Our goal is to provide long-term cash generation and profitability at Brucejack," said Pretium President and CEO Joseph Ovsenek.
The new mine plan outlines a good start on this objective.
Over the next 10 years, Brucejack is forecast to produce 5.29 million oz of gold at an all-in sustaining cost of US$535 per oz.
Over the entire 14 years outlined in the plan, the mine is expected to produce 6.17 million oz of gold at an all-in sustaining cost of US$539/oz.
At current gold (US$1,300/oz) and silver (US$16.90/oz) prices, this operation produces a net present value (5 percent discount) of US$2.59 billion.
Brucejack achieved commercial operation in mid-2017 and the information gained over the past 1.5 years helped to refine the new mine plan, including a reduction in reserve gold grade to account for more dilution from internal waste material than was originally anticipated.
"Since achieving production at Brucejack we have processed over 1.5 million tonnes (metric tons) of ore and produced over 500,000 ounces of gold, providing us a solid foundation of operating experience and key metrics to update the life of mine plan and outlook for the mine," said Ovsenek.
Looking beyond the 14 years outlined in the mine plan, Pretium launched a 70,000-meter 2019 underground drill program early in the first quarter that is expected to improve reserve definition ahead of mining and expand the reserves at the Valley of the Kings.
Opportunities for expansion are located at depth, to the west, to the east, and to the north-east of the currently defined reserves.
So far, more than 24,000 meters of drilling in 183 drill holes has been completed this year. The exploration portion of this early drilling focused westward and at-depth below the 1200-meter level of the current development.
Drilling will continue through the year and is expected to include zones prospective for additional reserve expansion to the northeast of and below the currently defined reserves, where previous drill programs have indicated the continuation of high-grade gold mineralization. A re-interpretation of previous drill results from the north-east indicates the presence of a repetition of the key stratigraphy that hosts high-grade gold mineralization in the Valley of the Kings.
Exploration drilling in 2015 intersected high-grade gold 1,000 meters to the east of the Valley of Kings below the Flow Dome Zone. Resource expansion drilling towards the Flow Dome is planned for later in the year depending on development and permitting.
"Brucejack has proven itself as a low cost, highly profitable mine. Now with reserve expansion drilling underway, we are focused on demonstrating the potential for Brucejack to be a top-tier gold producer well into the future," said Ovsenek.