GHD | Oceana Gold (New Zealand) Limited | 12537997 | Gladstone Pit TSF 40 Figure 26 Sensitivity analysis showing post deposition settlement versus time for different filling rates 5.5 Freeboard 5.5.1 Wave run-up Overview An empirical based assessment of a sub-aerial landslide / rockfall has been completed to assess the possible wave run-up heights if a failure of the pit wall was to occur. The assessment was based on published literature on impulse waves (Heller et al. 2009) and does not include stability analyses or an assessment on the probability of failure of pit walls. PSM (2021) demonstrated that the likelihood of a planar and wedge scale at the inter-bench scale is low. Similarly, the risk of global failure is also low. This risk has been further reduced by the shallow slope angles of the as-mined surface above the final tailings level. The assumed failure mass is illustrated in Figure 27. The assumed bulk volume of the failure mass was 10,000 m3. Three failure scenarios were considered. These are illustrated in Figure 28 and summarised as follows: 1. A failure at location A and wave run-up at location X. 2. A failure at location B and wave run-up at location X. 3. A failure at location B and wave run-up at location Y.
RkJQdWJsaXNoZXIy MjE2NDg3