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Frequently Asked Questions

Operations

What kind of mine has been developed at Brucejack?

Brucejack is a high-grade underground gold mine. Commercial production was announced on July 3, 2017.

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How big is the mine at Brucejack?

In 2018 Pretivm has been permitted to increase production by 40% from 2,700 to 3,800 tpd. The area of mine site itself, including the camp, covers approximately 10 hectares.

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What does the mine produce?

Brucejack produces predominantly gold with some silver. About 50% to 60% of the gold is produced as gold-silver doré bars, and the remainder is produced as a gold-silver concentrate.

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How is the ore extracted?

The mining method at Brucejack is long-hole stoping. This bulk underground method was chosen because the deposit is characterized by stringers of high-grade gold disseminated throughout lower grade gold (0.5 to 2.5 grams per tonne) quartz stockwork. Horizontal drifts are driven along two sublevels, and rock is blasted vertically from the upper level to the lower level along strike. The stope void left behind is then back-filled with waste rock and tailings mixed with cement.

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How is the ore processed?

The extracted rock is dumped into an underground crusher (which reduces dust and noise in the open air), crushed, and conveyed to surface. It is then put through a grinding circuit where it is ground to 75 microns. This material then goes through a gravity concentrator to extract the free gold, from which we will produce gold-silver doré bars. The remaining rock is processed in flotation cells and concentrated down to less than 10% of its initial mass. This is the flotation concentrate which is trucked from site and sold to smelters and metals traders.

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Where is the ore transported, and how?

The gold-silver doré bars are flown out from site and sold to refiners. The concentrate is trucked out and either transported by rail or ship to end buyers.

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When did the mine begin commercial production?

Commercial production at Brucejack Mine was announced on July 3, 2017.

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Environment

Does the mine use cyanide?

No. In processing, the majority of the gold is liberated through grinding and gravity separation. The remainder is separated through a conventional flotation process.

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Where does the mine’s waste rock go?

During the initial development of the mine, waste rock (estimated at approximately 2 million cubic meters, subject to the feasibility study) will be deposited in Brucejack Lake, an approximately 100-meter deep lake with an estimated volume of over 30 million cubic meters. Once stope voids have been developed from operations, waste rock will be deposited back underground.

Waste rock from historic underground development at the property was deposited in Brucejack Lake as part of reclamation in 1999. Brucejack Lake is not fish habitat, and no fish have been captured there historically or in 2010 and 2011 surveys.

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What about tailings from the mine?

Up to 50% of the tailings from the Brucejack mine (estimated at approximately 6 million cubic meters, subject to the feasibility study) are to be deposited in the bottom third of Brucejack Lake, with the remaining 50% to be used for paste backfill and deposited back underground. Studies are underway to maximize the amount of tailings to be placed underground.

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Will the mine impact area waterways?

The mine at Brucejack is not expected to impact the area waterways. Brucejack Lake is a glacial lake with minimal turnover. Its outlet is Brucejack Creek, which flows west under Sulphurets Glacier, into Sulphurets Creek (~7 kilometers away), and then ultimately to the Unuk River (~20 kilometers away), where it has minimal contribution. The Brucejack Creek watershed comprises approximately 3.5% of the Unuk River watershed.

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Are there fish in the vicinity of the mine?

Brucejack Lake does not support fish and is not considered fish habitat. It is at high elevation and is covered by ice approximately 10 months of the year. Its outlet is Brucejack Creek, which flows west downstream ultimately into Sulphurets Creek. There is an approximately 200-meter barrier (waterfall) on Sulphurets Creek located approximately 20 kilometers from Brucejack Lake which prevents fish from moving upstream.

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Are wildlife impacted by the mine?

The mine area itself is above the tree line in Alpine tundra at an elevation of 1,400 meters. It has minimal soil development due to its recent de-glaciation, so does not host significant animal habitat. The access road to the site traverses lower elevation areas with mature vegetation, and wildlife mitigation measures will be in place along it, as well as management measures such as gated control at Highway 37.

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How do you ensure that your contractors at the Brucejack site comply with the same environmental standards as Pretivm?

All contractors working at the Brucejack site must comply with the terms of Pretivm’s Environmental Policy. We maintain Standard Operating Procedures which address the environmental impacts of potentially harmful supplies and their use. Third party audits are conducted for potentially harmful products as well as the use, storage methods and transportation of those products. All non-compliances are reported as part of the regular environmental reporting required by our permits to operate the mine.

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What does Pretivm do to address greenhouse gas emissions at the Brucejack Mine?

Total direct greenhouse gas emissions data for Brucejack are reported to Canadian and provincial regulatory agencies as part of our environmental monitoring and reporting program. The emissions are not above the threshold that requires third party verification. We are conscious of the importance of limiting greenhouse gas emissions and incorporated energy efficiency into the design and operation of the Brucejack Mine.

Though it is remote, Brucejack is connected to the BC Hydro transmission grid to access hydro-electric and natural gas power. Other specific efforts to date have included: the use of double chambered incinerators, the use of scrubbers in the mill and assay lab and the initiation of recycling and reuse programs where practical. We reduced power consumption by installing variable frequency drives to increase efficiency in the mill building, and installed a pebble crusher which further grinds ore to increase the efficiency of the ball mill. LED high-bay lighting was installed in the mill building. Additionally, we have a stated “local preference” for sourcing employees, vendors and contractors and services, which also serves to reduce our carbon footprint.

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Is there information available on Brucejack’s air emissions?

Quantitative information on Brucejack’s reported air emissions is available through the government’s publicly available National Pollutant Release Inventory.

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How does Pretivm account for the water it uses to operate the Brucejack Mine?

Water use and withdrawal as well as wastewater discharge is monitored and reported to the Canadian and provincial regulatory agencies pursuant to our permit requirements. We recycle treated water through the mill, and all water used is treated and returned back to the environment.

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Does Pretivm have a waste management program?

Pretivm complies with the business waste separation and recycling program in place at its head office in Vancouver. At the Brucejack site, the Waste Management Plan addresses the prevention and minimization of domestic and industrial waste products to the environment. Waste management programs are in place which address waste separation and recycling, as well as industrial, chemical and hazardous waste disposal, pursuant to our operating permits. Our waste facilities are inspected.

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Permitting

What is Brucejack’s permitting status?

Pretivm has been issued all of the major regulatory permits and commercial production at the Brucejack Mine was announced on July 3, 2017.

Brucejack has received:

  • Mar 27, 2015 - BC Environmental Assessment Certificate
  • July 31, 2015 – Federal Environmental Decision Statement
  • Sept 1, 2015 – Mines Act
  • Sept 1, 2015 – Environmental Management Act
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How does the permitting process work?

The federal and provincial governments provide the requirements for the Environmental Assessment Certificate (EAC) application, and advise of the data gathering and community consultation requirements. Once filed, the British Columbia Environmental Assessment Office (EAO) has 180 days to assess, and the provincial Ministers then have 45 days to approve. From the date that the Federal Environmental Assessment Agency (CEAA) commences its assessment, the federal Minister has 365 days to make a decision. As of Sept 1, 2015 Pretivm has been issued all of the major regulatory permits and commercial production at the Brucejack Mine was announced on July 3, 2017.

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Community

What First Nations are in the area of the Brucejack Mine?

The Brucejack Mine access road traverses the asserted traditional territory of the Skii km Lax Ha First Nation, and where it crosses the Bell Irving River near Highway 37 it is located in the asserted territory of the Tahltan First Nation. The Brucejack Mine access road is located in the Naas Area as defined by the Nisga’a Final Agreement.

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Has Pretivm been engaging with the local First Nations and communities?

Pretivm has been providing ongoing project updates to the leaders of several First Nations and northern BC communities in the general vicinity of the Brucejack Mine. Representatives have visited the site, and many individuals have worked at site as Brucejack has evolved from its beginnings as a small exploration project. We will continue to provide project updates on Brucejack as it progresses, and will continue to extend employment opportunities and build commercial relationships in northern BC.

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What are their concerns about a mine at Brucejack?

The high-grade gold underground Brucejack Mine is located in a remote area with a relatively small environmental footprint. One particular issue we have heard raised is how the Mine will contribute to the cumulative impacts of the traffic on Highway 37, as we truck concentrate to the Port of Stewart or to the CN railway near Highway 16. We have advised that our concentrate traffic will comprise up to four to six 40-tonne trucks per day based on our processing rate at a concentration of 10%.

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How will local communities benefit from the Mine?

During construction Brucejack has employed approximately 900 people and, as a 3,800 tonnes-per-day underground mine, will employ approximately 600 - 700 people per year over the life of the mine for an array of technical and non-technical jobs in both surface and underground operations. We are committed to making local employment a priority, and will seek to engage in training partnerships with educational institutions and other organizations. We are also committed to sourcing local contractors and supplies from northern BC where possible.

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