Feed to the plant is a blend of three designated ore types commencing predominantly with saprolite and transition material (saprock) for the first three years. Fresh rock mill feed will gradually increase from Year 4 onward. Milling rates will be 7.5 million tonnes per year for the first three years of operation, 6.5 million tonnes per year for the fourth year and 5.4 million tonnes per year thereafter when mill feed is entirely fresh rock.
Mining is carried out using a conventional drill, blast, load and haul surface mining method with an owner fleet. Annual mining rates are estimated at 32 million tonnes per year for the first four years, decreasing to 25 million tonnes per year until eventually stabilizing at 15 million tonnes per year. Grade control samples are collected using reverse circulation drills with blast hole rigs used for production drilling. Loading is accomplished using hydraulic excavators and wheel loaders.
Essakane ore is processed using conventional crushing, milling and carbon-in=leach ("CIL") gold plant.
The mine plan calls for predominantly saprolite and transition ore feed in the initial four years of operation, followed primarily by fresh rock ore feed for the remaining mine life. Essakane realized an opportunity to increase mill throughput during the initial four years of operations and thereby increase forecast gold production, reduce unit operating costs and improve financial returns despite a marginal increase in capital costs.
Furthermore, by taking advantage of grinding in cyanide, optimizing slurry density by thickening ahead of leaching and the inherent faster leaching kinetics of saprolite, it was concluded that no additional CIL tankage was required and no significant impact on recovery would be observed at a plant throughput of 7.5 M tpy for predominantly saprolite and transition ore feed.