Ausenco provided Engineering, Procurement and Construction Management services for the third phase of the development and modernisation of the Gibraltar copper-molybdenum mine, located in McLeese Lake, British Columbia, Canada. This project is known as the Gibraltar Development Plan 3 (GDP3) Project.
Client requirements
The GDP3 project will increase the milling capacity at the mine with minimal interruption to existing copper and molybdenum production. The project included the construction of a new stand- alone concentrator, which will add an additional 30,000 tons per day to the processing capability. The project incorporated additional primary grinding, secondary grinding, regrind, rougher flotation, cleaner flotation, concentrate filtration and tailings pumping capacity as well as various ancillary systems and upgrades.
A stand-alone molybdenum separation plant was also constructed to replace the existing molybdenum circuit; the new molybdenum plant will more than double the mine’s molybdenum metal production, to approximately 2.5 million pounds per year. These modifications and upgrades will enhance Gibraltar’s operating flexibility and reliability and ensure that the mine continues to be an economic cornerstone for the region for years to come.
Project solutions and approach
The GDP3 project will increase the overall processing capacity to 85,000 t/d with an annual copper production averaging 165 million pounds.The schedule for the GDP3 Project was developed at the onset of the project to detail all Engineering, Procurement and Construction timelines for each discipline and project area. The total time from EPCM award to mechanical completion for GDP3 was forecast as 20 months. The project critical path flowed through procurement of the Ball and SAG Mills and the finalization of the #2 Concentrator engineering design required to expedite tendering and award activities of the pre-engineered building, in order to expedite the receipt of the foundation loads required to finalize concrete designs and initiate early site construction activities.
The addition of a new concentrator increased Gibraltar’s total processing capacity to 85,000 tons per day. The stand-alone concentrator was designed to minimize changes within the existing concentrator and consequently minimize production disruptions.
Outcomes and achievements
- Over 1 million manhours without a lost-time incident.
- Over 500 workers GDP3 project directly employed at the peak of construction
- Minimal interruption to existing production during plant shutdowns.
- Optimised existing site facilities and systems to provide cost-effective solutions.
- Previously completed an update to a 2008 Scoping Study for GDP3, incorporating process and layout optimisations made possible by the completion of the previous project phases.