GHD | Oceana Gold (New Zealand) Limited | 12537997 | Gladstone Pit TSF 39 Figure 25 shows the estimated dry density profile after the tailings are fully consolidated. The estimated dry density ranges from approximately 1.02 tonne/m3 to 1.40 tonne/m3. Based on the current modelling, closure capping works would be anticipated to begin approximately seven to ten years post-deposition. The capping of the TSF is expected to take 12-24 months. Figure 24 Post deposition settlement versus time Figure 25 Final dry density profile 5.4.3 Sensitivity analysis Sensitivity analysis was completed to demonstrate the effect of filling rate on the post deposition settlement and the results are shown in Figure 26. These results can help to guide the operation of GOP TSF such that the facility can be operated with a view towards closure. In the sensitivity analysis, filling rate ranged from 2.5 years to 10 years. The post deposition settlement was estimated to be 1.9 m for a 10-year filling time and 4.4 m for 2.5-year filling time. 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 20.0 40.0 60.0 80.0 100.0 Settlement (m) Time (year) 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 0.0 0.5 1.0 1.5 Depth (m) Dry density (t/m3)
RkJQdWJsaXNoZXIy MjE2NDg3