Pan Mine Completes $7.5-million Leach Pad Expansion, Adding Four Years of Stacking Capacity
Calibre’s Pan Mine in Nevada recently celebrated a major milestone with the successful completion of a $7.5-million expansion to its heap leach pad, the facility where gold is extracted from ore. The expansion adds 1.6 million square feet of new liner, which adds an additional four years of capacity at today's mining rate.
Behind this accomplishment lies incredible levels of teamwork and dedication. Seamless collaboration between the 45-person project team and Pan Mine staff was critical in meeting the project’s safety, quality, schedule and cost goals.
"Both parties were incredibly vested in making this project successful, and that's why we were able to hit every milestone," says Dan Ferriter, Calibre Environmental Affairs Vice-President and Project Manager. "From start to finish, it was a group effort."
Safety First, Every Step of the Way
Safety played a central role on the project from day one. A key factor in selecting the general contractor, High Mark Construction and its subcontractors, for instance, was a rigorous safety evaluation during the bid review stage.
From equipment assessments to on-the-ground oversight, Pan Mine’s safety team was also actively involved in all phases of the project. “Our safety team spent a ton of time on this project. It wasn’t just to check a box – they pored through every piece of equipment to make sure it was right,” says Dan. “They spent two weeks on the portable crusher alone, for example, before they would release it to work.”
This dedication to safety paid off. Over the course of approximately 41,000 work hours, the project finished without an injury. “That’s a major achievement on the safety side, and a big positive for the mine, because it contributes to the mine safety record, as well,” adds Dan.
Stringent Quality Control for Long-Term Reliability
Building a leach pad that will use cyanide solution requires stringent quality control, not just by Calibre personnel, but also by independent third parties, who provide a crucial added layer of verification. These included the project’s engineer of record, SRK consulting, which designed the expansion, and WSP Engineering, for onsite QA/QC.
The project adhered to rigorous QA/QC protocols for subgrade preparation, liner installation and the overliner cover, to ensure long-term environmental, safety and operational efficiency. Four full-time on-site contractor personnel, along with a dedicated lab, oversaw the QA/QC process.
“One reason the QA is so rigorous is to protect groundwater in the area,” says Dan. “State of Nevada regulations require zero degradation to groundwater, so even trace amounts of cyanide are unacceptable. It's a zero-discharge facility, meaning from the liner to the ponds and back again, it’s a continuous loop, with absolutely no discharge.”
Strict quality controls are also essential to ensure the long-term structural integrity of the leach pad, preventing potential failures that could lead to environmental contamination or costly repairs.
The QA data, construction records, and final surveys were compiled into a Final Record of Construction and As Built Report, which was reviewed and approved on September 20, 2024, by the Nevada Department of Environmental Protection (NDEP). The project is now fully authorized to proceed with operations.
On-Time Delivery for the WIN
The project timeline, from design through demobilization and final QA reporting, spanned 15 months, with the five-month construction phase finishing precisely on its scheduled completion date of August 13, 2024.
This is a testament to our team’s ability to deliver, even in the face of minor challenges and site constraints. One example: measures required to protect the spring breeding season of local sage grouse populations – which meant limiting morning noise between the hours of 5 a.m. to 9 a.m. from March through May.
Dan attributes the smooth execution of the project to careful planning and preparation. “We got approval at the end of last year to go forward, and we were able to procure all the materials in January. So all the material deliveries were really on time at the mine,” he says.
Cost management was another win, with the project’s final price coming in at $7.5 million, under the $8 million authorized for expenditure. By optimizing subgrade elevations and construction methods for the overliner, the team delivered meaningful savings, notes Dan.
Pan Mine’s Expansion in the Big Picture
The heap leach pad expansion enables Pan Mine to continue its contribution to the Calibre portfolio of assets. “It positions us to incorporate new discoveries into mineable ounces in fairly short order. We've had some exciting discoveries in the last couple of years, and now we have the capacity to process future new deposits as we go forward,” says Dan.
Translation? More efficient operation and fewer holdups – which is excellent news for Calibre, its investors and its stakeholders.
To learn more about Pan Mine, including Mineral Resources and Reserves, visit our website.