Ootsa is an advanced stage exploration project in British Columbia, Canada, containing pit constrained NI 43-101 compliant resources of copper, gold, molybdenum, and silver.
The project is 100% owned by Canadian company Surge Copper (previously Gold Reach Resources).
An updated Resource Estimate and Preliminary Economic Assessment (PEA) for the project was published with an effective date of January 2016.
In June 2022, Surge Copper announced an updated mineral resource estimate that increased Ootsa Measured and Indicated Resources by 96% to 439Mt grading 0.32% CuEq.
Location details
The Ootsa mine is located on the south shore of Nechako Reservoir in west central British Columbia. The location is approximately 120km by gravel road south of Houston.
The 72,710-hectare property consists of 120 contiguous non-surveyed mineral claims. It consists of the East Seel, West Seel and Ox porphyry deposits.
The Huckleberry Copper Mine is situated adjacent to the Ootsa Property.
Geology and Mineralisation
The Ootsa Property is situated within the Stikine tectono-stratigraphic terrane. It is underlain by a series of juxtaposed fault blocks featuring tilted and locally folded strata of the Telkwa, Nilkitkwa, Whitesail, and Smithers formations.
Multi-phase intrusive complexes cut these rocks and are correlated to the Late Cretaceous Bulkley Intrusive suite.
The rocks are cut by multi-phase intrusive phases including diorite, granodiorite, quartz diorite, porphyritic quartz monzonite, porphyritic granodiorite, feldspar porphyry, and quartz feldspar porphyry.
Porphyry style Cu-Au mineralisation is found in the East Seel deposit within a coarse feldspar-biotite porphyry.
The mineralisation is associated with quartz-chalcopyrite-magnetite-pyrite veins with strong potassic alteration.
The West Seel deposit contains porphyry Cu-Au-Mo-Ag mineralisation hosted in different intrusive porphyritic rocks and in fine grained clastic sedimentary rocks found along the intrusive margins.
The Ox deposit hosts porphyry Cu-Mo mineralisation in altered sedimentary rocks near the western margin of a granodiorite porphyry stock.
Ootsa Property Mineral Resource Estimate
In a report published in 2016, the total mineral resources in measured and indicated categories for Ootsa are 224.2Mt containing 1,854Mlbs copper equivalent (CuEq) at a grading of 0.37%, 1,109Mlbs Cu at a grading of 0.22%, 1,062Koz Au at 0.15g/t, 104mlbs Mo at 0.021%, and 20,457Koz Ag at a grading of 2.8g/t.
Surge Copper updated the mineral resource estimate for the property in June 2022 based on a drill hole database comprising approximately 152,000m of diamond drilling.
According to June 2022 estimate, the total mineral resources in measured and indicated categories are 438.6Mt containing 1,694Mlbs of CuEq at a grading of 0.32%, and 1,694Mlbs Cu at a grading of 0.18%, 1.6Moz Au at 0.12g/t, 167Mlbs Mo at 0.017%, and 29.5Moz at a grading of 2.1g/t.
Mining and Ore Processing at Ootsa Project
The Ootsa Property deposits are planned to be mined by conventional truck/shovel open pit methods. The plan involves mining three open pits starting with East Seel, then Ox, and finally West Seel.
The copper project is expected to remain operational for 12 years followed by a decommissioning process that will take another one to two years.
The nominal rate of mining is expected to be 13.4Mtpa with production generally ranging from 10-20 Mt annually.
A mining contractor will provide equipment fleet and operate the conveyor system that will transfer the ore to the mill from the site.
The mining fleet will include one 300tonne hydraulic excavator and one 200tonne hydraulic excavator loading 7-9 135tonne rigid-frame haul trucks.
The mill feed will be hauled to a semi-mobile jaw crusher at the edge of the Seel and Ox open pits from where it will be conveyed to the mill.
The crushed mill feed will undergo primary and secondary grinding with the underflow directed to bulk flotation.
Copper will be depressed to facilitate flotation of molybdenum as a separate concentrate. Subsequently, they will be dewatered and dried before shipment.
Tailings will be transferred to a mined-out open pit near the mill for storage.
Key Project infrastructure
The project will involve establishing field maintenance facilities, offices and lunchrooms at the Permanent Transfer Point where the Seel and Ox overland conveyors will meet.
It also plans to use facilities at the adjacent mine to support operations.
The Ootsa property can be accessed via all-weather gravel roads.
Power will be supplied by an existing 138kV transmission line from the BC hydro grid.
Contractors involved
P&E Mining Consultants was the lead engineering firm for the Updated Resource Estimate and Preliminary Economic Assessment on Ootsa Property published in 2016. Knight-Piesold Consulting and ERM Consultants Canada also supported.
Surge Copper contracted ALS Metallurgy Kamloops for advanced metallurgical test work programme that continued from February 2022 to October 2022.
Geotech carried out a helicopter-borne natural field ZTEM and aeromagnetic survey over Ootsa property.
The geophysical survey of the property was completed by SJ Geophysics.
