Figure 35. Potential interaction of the Upper Mundic Gully TSF failure discharges with the proposed Sandstone Gully TSF embankment
Additionally, as the Sandstone Gully TSF embankment is proposed to be constructed over a significant
portion of the OCP void, the Upper Mundic Gully TSF dam break discharges are expected to be less
attenuated within its reduced footprint, resulting in increased spills to the downstream site infrastructure
and the urban perimeter of the township of Mt Morgan.
Dam break assessments will be revisited in further studies to include the final proposed Sandstone
Gully TSF footprint in the hydrodynamic models to further evaluate the risks/credibility of embankment
erosion and the potential for a cascade failure and a consequent CCA re-assignment.
4.3.11. Process Plant Flow Sheet
Heritage Mineral’s tailings reprocessing strategy is based on a simplified process flowsheet,
incorporating GreenGold’s (ReCYN) Technology. As the name suggests, ReCYN reduces cyanide
consumption by 50%, capturing free cyanide from the plant tailings and recycling it back into the leach
circuit while recovering valuable metal complexes for sale. In the treatment process, ReCYN removes
contaminants from the tailings stream.
The processing plant flow sheet is provided in Figure 36. The basic operational philosophy of the
processing system is that latent tailings feed material is cyanide leached after fine grinding, with
subsequent recovery of gold, copper, free cyanide and Weak Acid Dissociable (WAD) cyanide using a
strong base resin. Resultant tailings are then transferred via pipework into the authorised disposal
areas.
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Wulguru Technical Services Pty Ltd – Supporting Information to Amend an Environmental Authority
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