Trevali Mining Corp is progressing well on construction and mine re-start activities at its wholly-owned Caribou polymetallic mine and mill complex located in the Bathurst Mining Camp of northeast New Brunswick, Canada. Both surface and underground development programs at Caribou continue to advance and the project status remains on schedule for start-up commissioning in the first half of 2015. A summary of key current activities is provided below:
MILL
- The new 3,000-t/d SAG mill major components are installed and the mill will be commissioned in Q1 of 2015
- The three IsaMills installed at Caribou have been inspected by the XPS and are in excellent condition for start-up. The company is proactively replacing the electric motor bearings for enhanced reliability during commissioning and going forward
- The zinc and lead flotation circuits have been cleaned and repaired where necessary, and copper circuit design and tendering is nearing completion
- All mill motors and electrical drives have been cleaned and serviced by OEM representatives
- The majority of the pumps have been refurbished and/or replaced and spare pumping capacity components have been sourced from the nearby Brunswick-12 mine and mill complex that ceased operations in 2013
- Plant instrumentation refurbishment is progressing as equipment becomes available and remains on track for H1-2015 mill commissioning.
UNDERGROUND
- The new portal construction commenced in early November and is advancing to schedule. Surface breakthrough is anticipated in Q1-2015 and will ultimately result in significant operational efficiencies by reducing the surface haul distance to approximately 100 m to the Fine Mineral Bins versus the previous surface route of some 1.5-km. It is anticipated that this will decrease haul costs, improve underground fleet availability in addition to improving winter production capabilities
- About three years of underground development is currently in place: In detail, ramp and level rehabilitation and access to two of the first four production areas are approximately 90% and 75% complete respectively. The third and fourth production zones are 40 to 50% complete and continue to progress to schedule and plan. There are currently some 600,000 t of mineralised material available for production
- Surface crusher installation is in progress to a newly designed radial stacking pad. Based on the company’s successful Santander commissioning, Trevali is currently planning to stockpile about 60-80,000 t of underground material prior to commencing Q2-2015 mill commissioning
- The main dewatering pumps are fully installed and site is currently dewatering at full 600 gallon-per-minute capacity. The mine is currently dewatered to some 250-m subsurface
- The underground paste backfill study is advancing and results are expected in early Q1-2015.
SURFACE WORKS
- Zinc and lead concentrate shed rehabilitation is in progress and will improve winter concentrate load-outs and management. Copper concentrate shed planning and engineering is advancing well
- Several site bridges have been replaced in order to improve access to the Tailings Management Facility (TMF). The reclaim pumping station and water polishing pond areas have be raised and placed on new foundations to facilitate potential future TMF expansions
- Geotechnical drilling has been completed in order to access long-term TMF planning
- The mill site has been contoured to improve surface water management
- Fire suppression system is refurbished and fully operational.
Exploration targeting and drill testing of potential extensions of both the East and North Mine Limbs has resulted in the intersection of significant intervals of massive sulphide mineralisation ranging from 7 m to plus 45 m downhole thicknesses and remain open for extension. Assay results are pending.