Eagle Gold Mine Commercial Production Shows Early Returns
TORONTO - Victoria Gold Corp., President and CEO, John McConnell, said, “These inaugural financial statements under Commercial Production show the very early returns from many years, of dedicated work, conviction and investment. These transformative efforts have set Victoria Gold and its stakeholders up to begin reaping great benefit from all of the past and continuing efforts. Aside from the usual teething issues and learning curve experiences common to all start-ups, we are very pleased with our progress as we have moved in to and beyond Commercial Production and remain highly confident the best is yet to come over a very long mine life.”
Operational Highlights: Achieved Commercial Production at Eagle Gold Mine on July 1, 2020; Mine production in the quarter was 2.1 million tonnes of ore; Ore stacked on the heap leach pad in the quarter was 1.9 million tonnes at an average grade of 0.85 grams per tonne (g/t); and Gold production was 35,312 ounces in the quarter.
During the three months, the Eagle Gold Mine produced 35,312 ounces of gold, and sold 32,029 ounces of gold. A total of 2.1 million tonnes of ore were mined, at a strip ratio of 2.1:1 with a total 6.5 million tonnes material mined. Mining and processing activities continued to ramp up toward full production during the third quarter of 2020. Total tonnes mined were above forecast while ore mined was lower than forecast due to bottlenecks being resolved within the processing circuit. This allowed the mine to utilize available resources to advance waste stripping to ease future ore release requirements.
A total of 1.9 million tonnes of ore was stacked on the heap leach pad at an average head grade of 0.85 g/t Au. The throughput rate was 20.8 k tonnes per day. Tonnes stacked on the heap leach pad increased during Q3 2020, however, total tonnes stacked and resultant gold production was lower than forecast. Importantly, both gold grade and metallurgical recoveries are reconciling well against the Eagle reserve model and a significant gold inventory is building on the heap leach pad.
A number of improvements related to material handling within the process circuit were completed, or are in progress, during the quarter. These corrective measures are significantly improving reliability and, in turn, will improve ore stacking and gold production going forward.
Material handling improvements within the process circuit are proceeding well. A comprehensive Operations Reliability Enhancement Phase is well underway to improve equipment mechanical availability and maintenance practices. The primary goal of the Operations Reliability Enhancement Phase is to increase plant uptime and thereby achieve throughput design capacity and lower unit costs. Key areas for improvement include: feeder and feed chute design; wear liner selection and design; control logic improvements in the process system and addressing under designed capacity of the mobile grasshopper conveyor stacking system on the heap leach pad.
The initial feeder and feed chute designs have proven to be overly complex with many wear liner configurations, insufficient access and limited inspection hatches. The feeders, which feed ore to the tertiary screens and crushers, have been reconfigured to a conveyor style arrangement. This has greatly reduced liner wear and belt damage both of which have significantly reduced maintenance requirements and improved uptime. Feed chutes have been redesigned to ensure a high level of commonality in wear liner packages, reducing inventory and simplifying maintenance requirements. The feed chute design enhancements have also improved maintenance access and increased the number of inspection hatches. Combined these improvements enable better asset management and speed up maintenance operations.
The ore has proven to be more abrasive than initially assumed in the detailed design. This has caused significantly more liner wear than expected, requiring more frequent maintenance downtime and increased cost. Increased abrasion is being addressed by switching to high abrasion cast liners which significantly improve uptime and overall reliability. Liner design and molds are complete and the new liner packages are arriving on site through the course of Q4. On site testing of these liners have demonstrated to be very effective in reducing wear and improving plant uptime.
Considerable process control logic enhancements were possible now that a baseline of operational history has been established. The control logic was originally established during the last stages of construction and while the basic framework was in place, our plant operators were able to make considerable improvements to the way the plant is controlled and operated.
Some components of the mobile conveyor stacking system used on the heap leach pad to convey material to the active leaching face have under designed motor capacity. Specifically, there are 8 mobile grasshopper units that are powered via a single 75 horsepower motor. These units have demonstrated a conveyance capacity that is 80-85% of design capacity and, being the last piece of equipment along the line, are bottlenecking throughput on all upstream equipment. The grasshoppers in question are readily modified to accept 200 horsepower motors. All material for the modifications have been ordered and are expected to arrive in Q4. Once all the grasshoppers have been upgraded to 200 horsepower the system will be capable of higher hourly throughput tonnages.
As operations have ramped up, the Covid-19 pandemic has persisted and has had an adverse impact on operational performance. The company has benefited from the Yukon Government deeming mining an essential service to ensure operations have continued uninterrupted. However, government mandated restrictions have had a manageable but significant impact on employee turn-over, on site vendor support, supply chain operations and costs.