- Imperial acquired Red Chris project in 2007
- Prov & Fed Environmental Assessment's issued 2005 & 2006
- mine construction commenced May 2012
- hydro transmission line completion May 2014
- mine start-up scheduled for mid-2014
- projected capital cost $500 million
- conventional open pit mine
- 30,000 TPD flotation mill
- 28 year mine life
Imperial's wholly owned Red Chris copper/gold property is located 80 km south of Dease Lake in the traditional territory of the Tahltan First Nation in northwest British Columbia. Access to the site is 20 km from Highway 37.
Red Chris Mine Construction UpdateRed Chris mine development is proceeding with 94% of the engineering complete as of September 30, 2013. Start of commissioning is scheduled for June 2014.
The 287 kV Northwest Transmission Line (NTL) from Skeena substation to Bob Quinn is under construction by BC Hydro with a planned completion date of May 2014. A subsidiary of Imperial is constructing the 93 kilometre extension (Iskut Extension) from Bob Quinn to Tatogga. The power line engineering design has reached 90% completion. Construction of access roads and right of way clearing for the Iskut Extension which began in July is 54% complete. A 100 person camp and laydown yards were established along the route to store and assemble lattice structure components. An experienced power line constructor has been retained to install foundations, structures, hardware and conductor.
Transmission Line Route
1Q2013 work completed:
- erection of a truck shop for the open pit equipment
- construction of a 2.7 km heavy haul road between the truck shop and primary crusher
- construction of a 2.5 km overland conveyor right of way and service road from the primary crusher to the coarse ore bin
- excavation for primary crusher and mechanically stabilized earth (MSE) wall at 95%, final blast scheduled for early May
- topsoil stripping in the tailings impoundment area
- installation of additional camp modules (camp facility capacity 480 persons)
2Q2013 work items included:
- construction of power line structure accesses on the 18 kilometre route from Tatogga to the mine site
- preparation of the primary crusher, MSE wall and transfer tower foundations
- installation 6,751 m3 of concrete to date into the process building foundations, grade beams, mill piers and raft slab
- construction of crane pads around the process building for steel erection starting in July
- installation of a water diversion and sediment control structures around the Tailings Impoundment Area (TIA)
- construction of foundation drains for the TIA North Starter Dam
3Q2013 work items included:
- placement of 2,852 cubic metres of concrete in the primary crusher, overland conveyor transfer towers and bents
- construction of the MSE wall at the primary crusher to approximately 60% complete
- installation of transformer concrete foundations at the main electrical substation
- installation of 16,396 cubic metres of concrete (project to date) in the process building and reclaim tunnel
- erection of structural steel, cladding and roofing in the process building and multi-plate in the reclaim tunnel
- setting the rougher tank cells, cleaner column cells, filter wash tank, filtrate tank, stock tank and thickener in the flotation bay
- mechanical installation of the overland conveyor, pebble crusher, vertimill base, apron feeders, chutes and pump assemblies
- placing and compaction of 1.3 million cubic metres of materials in the tailings storage facility
- construction of the tailings and reclaim lines
Construction at Red Chris to date has been funded by cash flow from operations, equipment financed by non-current debt, the Company's lines of credit with its bank and with a significant shareholder.
Capital CostsThe cost of constructing the Red Chris mine is estimated to be $500.0 million, a 12.7 % increase from the previous estimate of $443.6 million. The major areas of increase are attributed to:
- Scope Change: Process building footprint was expanded to provide a more functional operational layout, to provide for the concentrate thickener to be installed within the building, and to provide increased concentrate storage capacity which resulted in increased concrete and steel volumes. In the case of concrete quantities for the process plant, the increase was 70% due to the increased building size and geotechnical requirements.
- Labour cost increased by 30% from initial budget.
- Impact of change from HST to PST on April 1, 2013.
RED CHRIS MINE CONSTRUCTION
Red Chris InfrastructureThe Red Chris project is in the development stage of an open pit mining and milling operation. The planned mining fleet would include a 311mm electric rotary drill, 40m³ electric cable shovel, 20m3 wheel loader, 230 tonne capacity haul trucks and associated support equipment. Other mining fleet additions to assist with pre-development and construction include 178mm DTH drills, 12m3 diesel powered hydraulic excavator, 10m3 wheel loader and 86 tonne capacity rigid frame haul trucks and 40 tonne capacity articulated trucks. Ore would be fed to a 1.4m x 2.0m gyratory crusher for crushing to a nominal -150mm. Crushed ore would be held in a 120,000 tonne capacity intermediate stockpile before reclaim to the plant.
Plant design is based on a standard porphyry copper flow sheet employing SAG and ball milling, flotation, regrinding, thickening and filtering to produce a concentrate for export averaging 27% copper at a moisture content of 8%. The grinding circuit would include a 10.36m x 4.72m x 11,200kW SAG mill feeding one 7.32m x 12.80m x 13,428kW ball mill providing a primary grind of K80 of -150µ. Coarse rejects from the SAG mill would be crushed in a 600kW pebble crusher. Ball mill discharge would feed one bank of 5 x 200m³ rougher flotation cells followed by 1 x 183m3 and 1 x 61m3 cleaner flotation columns and a bank of 5 x 100m³ cleaner scavenger flotation cells. Cyclone underflow would be fed to a 4.12 m x 6.93m x 2,200kW primary regrind ball mill and a 4.6m x 4.4m x 14.3m x 1,120kW secondary regrind vertical mill to provide a K80 of -24µ. The primary and regrind product sizes were determined by G&T Metallurgical Services Ltd. to provide the optimum conditions for copper recovery and concentrate grade. Concentrate would be thickened and filtered and then loaded on B-Train trucks of nominal 50 tonne capacity for hauling to the Port of Stewart for shipment to smelters in the Pacific Rim.
Red Chris ExplorationThe Red Chris exploration program was suspended in May 2012 when the project focus shifted from exploration to mine development.
For additional information refer to the Company's Quarter Reports & Annual Information Form.
Forward Looking Information