The Diba orebody shows extensive oxidation at depths of up to 70 m and it presents continuous, higher grade, mineralization near surface, making it amenable to simple, productive, and costefficient open pit mining methods and agitated leaching at the Sadiola plant.
The pit optimisation was completed based on a selling price of USD$1,750/oz Au.
Pit shell selection was performed for mine design and planning. At Diba Pit 99 with a profit factor of 100% was selected. At Lakanfla Pit 57 was chosen with a profit factor of 83%.
Tonnage of PMI content inside the selected Diba pit shell includes 6,080 kt of PMI with an average grade of 1.22 g/t of Au and includes a stripping ratio (waste:PMI) of 1.04. Lakanfla pit shell includes 3,420 kt of PMI with an average grade of 0.70 g/t of Au and includes a stripping ratio (waste:PMI) of 0.99.
A conceptual mine design has been completed based on the optimal pit shell generated, assuming the use of rigid off road trucks with ~100t tray capacity. The pit design was prepared using a minimum mining width of 30m with a ramp width of 16m single lane; 25m dual lane and 10% gradient. Face angles used are 50° for the oxide zone, 60° for the transitional and 65° for the fresh rock zone.
The mining plan requires limited initial waste stripping using a PC1250-8 and a CAT365 excavator. Mining would be via conventional open-pit methods (drilling, blasting, loading, haulage and ancillary services). ........