Closure activities included the safe rehabilitation of the existing Tailings Storage Facility involving the re-profiling the downstream embankment to a flatter slope and incorporating rock armouring to provide buttressing and erosion protection to the facility. The embankment was raised to provide a wet closure solution which required modifications to the primary spillway and the introduction of a secondary (emergency) spillway. An array of monitoring instruments were introduced to the facility including piezometers, inclinometers, extensometers and InSAR monitoring.
The closure works involved alluvial gold sterilisation works that introduced concurrent mining and civil earthworks activities thereby minimising cost. The site for closure works were sterilised whilst utilising suitable overburden materials to construct closure landforms including large scale settlement ponds, river protection bunds, pit wave protection bunds, rocklined channels and wetlands. Particular aspects of the wetlands included large scale culvert structures, weir boards, waste dump landform stabilisation and
Supporting infrastructure included Alluvial Plant facilities such as a gold room, offices and security rooms.
During the course of the closure works the operations infrastructure including the process plant and accommodation and administration facilities were dismantled, packed and either sold or repurposed as closure infrastructure. This included the completion of closure accommodation facilities, offices and warehouse facilities.
