The dominant geological unit of the Project (the South of Embley Project) area is the Ferruginous Duricrust, which is derived from heavily laterised sandstones of the Bulimba Formation. Ferruginous Duricrust is essentially the same as the Andoom land system as defined by Godwin (1985) and Gunness et al. (1987). Between the bauxite and sandstone there is a transitional zone consisting of kaolinite clay, unlike the sharp ironstone-bauxite contact as in the East Weipa and Andoom mines.

The top of the bauxite strata is generally less than 1m below the natural ground surface. The average ore thickness across the identified reserves in the Project area is approximately 3.4m.

The Project (the South of Embley Project) currently has bauxite reserves that could sustain a mine life of about 40 years, depending on annual production rate. Mine life also depends on the extent to which mineable reserves may change in the future subject to ongoing resource evaluation and economic factors.

Vegetation would be cleared by bulldozers, following the wet season when the ground is sufficiently moist. Soil would be salvaged and returned by scraper or haul truck directly to mined-out areas undergoing rehabilitation where possible, or stockpiled for later respreading. The overburden above the bauxite would then be removed by front-end loader and returned to mined-out pits by trucks.

The top of the bauxite strata is generally less than 1m below the natural ground surface. The average ore thickness across the identified reserves in the Project area is approximately 3.4m. A shallow open pit would be developed whereby bauxite would be mined by front-end loader or excavator. Bauxite is relatively easy to dig and does not require blasting.

Crude bauxite ore is transformed into product by a process known as beneficiation. Beneficiation involves separation of the bauxite and waste materials through crushing, screening, washing and dewatering. No chemicals are added to the process. This process produces pea-sized pisolite product ore and tailings (consisting of water, fine bauxite pisolite, sands and clays). The particle size of tailings is less than 0.6mm.

Bauxite would originally be processed in the Boyd beneficiation plant. Production capacity may be increased by expanding the Boyd beneficiation plant and/or by building a second beneficiation plant at the proposed Norman Creek infrastructure area located approximately 15km south-east of the Boyd infrastructure area. The Norman Creek beneficiation plant would also be designed such that it can be expanded if additional capacity is required.

The tailings would be pumped in slurry form (30% solids by weight) to a TSF. The TSFs would be “turkey’s nest” dams where tailings are discharged from the perimeter wall into cells within the dam. The tailings solids would beach and suspended solids would settle out and water wouldbe decanted and pumped back to the beneficiation plant for reuse in processing.