This technical report presents the Moose River Consolidated Project in Nova Scotia, Canada, covering the Phase 1 operation at Touquoy and Beaver Dam and the Phase 2 Expansion at Fifteen Mile Stream and Cochrane Hill, with an effective date of 24 January 2018.
Report context
This NI 43-101 Technical Report on the Moose River Consolidated Phase 1 and Phase 2 Expansion was prepared for Atlantic Gold Corporation, with an effective date of 24 January 2018. The Moose River Consolidated Project is located in Nova Scotia, Canada. The Phase 1 operation consists of the recently-commissioned Touquoy mine and the planned Beaver Dam mine. The Phase 2 Expansion includes the Fifteen Mile Stream and Cochrane Hill deposits. A Feasibility Study was completed in 2015 on Phase 1. A Pre-Feasibility Study was completed in 2018 on Phase 2, evaluating the two deposits as stand-alone mines with their own plants and infrastructure, feeding concentrates to the Touquoy leach facility. The economic analysis presents the combined Phase 1 and Phase 2 Expansion results.
Processing route
Touquoy Process Plant (Phase 1)
The Touquoy process plant is located east of Moose River, northeast of the Touquoy open pit and northwest of the tailings management facility. The process design assumes a conventional flowsheet, including crushing, grinding, gravity recovery, carbon-in-leach (CIL), desorption/electrowinning/refining, tailings management and cyanide destruction. The plant is designed for an ore treatment of 2,000,000 t/a or 250 t/h based on an availability of 8,000 h/a, or 91.3%. The crushing section design is set at 60% availability as it operates outdoors and uses modular mobile equipment. The plant will accept Touquoy ore for the first five years of operation and thereafter ore from the Beaver Dam deposit at the same treatment rate using the same unit operations. The main difference between the ores is that Beaver Dam ore is harder and has a higher abrasion index.
Fifteen Mile Stream and Cochrane Hill Process Plants (Phase 2 Expansion)
Two stand-alone 2 Mt/a capacity mills are proposed for Fifteen Mile Stream and Cochrane Hill. The process will generally be the same at both plants and includes primary, secondary and tertiary crushing, followed by grinding by a ball mill in a closed circuit with hydrocyclones. Centrifugal gravity separation units will be installed to recover primary cyclone underflow gravity recoverable gold. The fines will report to conventional flotation cells and the coarse will report to HydroFloat™ cells to produce gold concentrate. Gold concentrate will be thickened and pressure-filtered before being transported by truck to the Touquoy process plant. The final tailings from both fines conventional flotation and HydroFloat™ circuit will be pumped to a tailings management facility at each site. Plant operation will require reagent storage, air, water services and an assay laboratory at each site.
Modifications to Touquoy Process Plant
The Touquoy process plant leach circuit will require the trash screen and carbon safety screen single deck panels to be interchanged for a higher-flow product due to the increase in mass throughput when treating material from Cochrane Hill and Fifteen Mile Stream. Additional acid wash and elution cycles are expected to be required. Given the increase in mass throughput, the existing intensive leach reactor and downstream electrowinning cell has been identified as a bottleneck, and therefore a new intensive leach reactor and electrowinning cell will be required at Touquoy. Gold room operations will require more frequent sludge presses, drying batch and smelting activities.
Key reported parameters
| Parameter | Unit | Design Value | Basis |
|---|---|---|---|
| Phase 1 ore treatment rate | t/a | 2,000,000 | Proposed design |
| Phase 1 plant availability | % | 91.3 | Proposed design |
| Phase 1 crushing section availability | % | 60 | Proposed design |
| Phase 1 design throughput | t/h | 250 | Proposed design |
| Phase 2 Expansion mill capacity (each site) | Mt/a | 2.0 | Proposed design |
| Phase 1 gold recovery (Touquoy and Beaver Dam) | % | 94 | Testwork derived formula |
| Phase 1 recovery formula | , | % gold recovery = (((h-0.087)/h)*100) where h = head grade | Testwork derived |
| Phase 2 average LOM gold recovery (Fifteen Mile Stream) | % | 88.5 | Testwork based estimate |
| Phase 2 average LOM gold recovery (Cochrane Hill) | % | 88.3 | Testwork based estimate |
| Phase 2 first year gold recovery (Fifteen Mile Stream) | % | 92.9 | Testwork based estimate |
| Phase 2 first year gold recovery (Cochrane Hill) | % | 93.1 | Testwork based estimate |
| Phase 2 final year gold recovery (Fifteen Mile Stream) | % | 73.8 | Testwork based estimate |
| Phase 2 final year gold recovery (Cochrane Hill) | % | 70.8 | Testwork based estimate |
| Phase 1 Touquoy unit operating cost | C$/t milled | 20.9 | Feasibility Study estimate |
| Phase 1 Beaver Dam unit operating cost | C$/t milled | 34.6 | Feasibility Study estimate |
| Phase 2 Fifteen Mile Stream LOM unit operating cost | C$/t milled | 19.2 | Pre-Feasibility Study estimate |
| Phase 2 Cochrane Hill LOM unit operating cost | C$/t milled | 20.9 | Pre-Feasibility Study estimate |
Technical qualifications
The metallurgical testwork for Phase 2 Expansion was completed on variability and composite samples that had higher gold grades than the corresponding mine plan weighted average grade. The report states that testwork on higher grade samples tends to overestimate metallurgical performance. Further testwork is recommended on samples with feed grades approximating the mine plan feed grades to improve confidence in metallurgical recovery. The Phase 1 recovery formula for Touquoy and Beaver Dam was derived from testwork considering the very similar recoveries obtained for each deposit and the similar head grades.
No deleterious elements are expected in the doré from Phase 2 Expansion.
Source: Moose River Consolidated Project, Nova Scotia, Canada, NI 43-101 Technical Report on Moose River Consolidated Phase 1 and Phase 2 Expansion, effective date 24 January 2018. Relevant sections: 1.9, 1.14, 17, 13.
