Mining at Cowal currently centres on the E42 deposit, with underground development of the GRE46 deposit underway, and studies ongoing for the E41 and E46 Open Pits. The gold deposits occur within the 40km by 15km wide Lake Cowal Volcanic Complex. The Lake Cowal Volcanic Complex is part of a dismembered ancient volcanic island arc, the Macquarie Arc, that formed around 480Ma, similar to modern day arcs in Indonesia and PNG. The deposits occur within a 5km (n-s) by 2km (e-w) trend known as the Gold Corridor. The gold deposits, E42, E41, E46 and GRE46 are structurally hosted, epithermal to mesothermal gold deposits occurring within and marginal to a >500m thick dioritic to gabbroic intrusion (Muddy Lake Diorite) doming the stratigraphically upright andesitic and dacitic volcaniclastic rocks and lavas. The CGO tenements also host the copper-gold porphyry prospect at Marsden/E43, and the volcanogenic-massive sulphide prospect at Decoy/E35. Gold deposits aligned along a north-south orientated corridor within the bounding Booberoi Fault on the western side and the Reflector Fault on the eastern side. The area is commonly referred to as the Gold Corridor. The current architecture and associated mineralisation within the Gold Corridor is related to a succession of intrusions exploiting pre-existing zones of weakness, most likely the Cowal Shear Zone. The intrusions have domed the camp, resulting in a faulted anti-form that plunges shallowly to the north-northeast. Gold mineralisati ........

The Cowal operation is currently an open pit mining operation utilising conventional drill and blast, load and haul methodologies, mining nominally 9m benches as 3 x 3m flitches. Mining commenced in 2005 and processing started in 2006. Mining is carried out with a company-owned fleet of mining equipment. Ore is hauled by truck from the pit face to either a stockpile area or directly fed into the primary crusher. Current mining at Cowal open pit is undertaken via conventional truck and excavator fleet, and the current operations demonstrate the appropriateness of this mining method. The 2021 Study used this mining method as the basis of the Ore Reserve estimate for the E42, E41, E46 and GR open pits. Minimum mining widths for benches were based on 45m and are generally exceeded in all pit stages. However, in the E42 Stage I cutback where the cutback stays inside the existing Stage H pit, the mining width reduces to about 30-35m, or the width of the Stage H ramp. To account for operational delays in these narrow areas, operational efficiencies were lowered by reducing the productive hours of excavators by 5% and increasing the loading spot times (truck interchange time at excavator) by 50%. Underground Mining method assessments indicated that sub-level open stoping (SLOS) with pastefill was the most appropriate mining method for the GRE46 underground deposit. This allowed maximum extraction of the economic portion of the deposit, while ensuring no surface subsidence due to ........

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