## 6 Quasi-3D Settlement Results
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline  & **S1** & **S2** & **S3** & **S4** & **S7** & **S11** & **A1** & **G1** & **R1** & **F1** & **C1** \\ \hline Maximum valley depth (m) & 29.1 & 39.1 & 51.4 & 30.7 & 26.5 & 22.7 & 69.3 & 60.7 & 47.7 & 43.2 & 31.4 \\ Maximum peak height (m) & 29.6 & 39.6 & 52.0 & 30.9 & 27.0 & 23.2 & 69.4 & 63.9 & 55.4 & 46.1 & 32.7 \\ Mean of 10 valley depths (m) & 29.1 & 39.2 & 51.4 & 30.7 & 26.5 & 22.8 & 69.3 & 61.0 & 48.3 & 43.3 & 31.4 \\ Mean of 10 peak heights (m) & 29.6 & 39.5 & 52.0 & 30.9 & 26.9 & 23.2 & 69.4 & 63.7 & 54.8 & 45.7 & 32.5 \\ Average elevation (m) & 29.3 & 39.3 & 51.8 & 30.8 & 26.7 & 23.0 & 69.3 & 62.3 & 51.5 & 44.2 & 31.8 \\ Maximum settlement (m) & 40.9 & 30.9 & 18.6 & 39.3 & 43.5 & 47.3 & 0.7 & 9.3 & 22.3 & 26.8 & 38.6 \\ Maximum slope (\(\%\)) & 0.4 & 0.3 & 0.5 & 0.2 & 0.3 & 0.3 & 0.1 & 2.3 & 5.1 & 2.1 & 0.9 \\ St. dev. of elevation (cm) & 11.0 & 8.9 & 14.4 & 4.9 & 9.8 & 10.6 & 2.8 & 72.6 & 151.4 & 0.6 & 0.3 \\ roughness (m) & 0.09 & 0.07 & 0.12 & 0.04 & 0.08 & 0.09 & 0.02 & 0.63 & 1.19 & 0.47 & 0.20 \\ Dist2D\_PeakValley (m) & 626 & 597 & 616 & 596 & 648 & 639 & 650 & 633 & 607 & 561 & 564 \\ Dist2D\_Peaks (m) & 441 & 457 & 455 & 510 & 428 & 460 & 417 & 464 & 429 & 456 & 456 \\ Dist2D\_Valleys (m) & 457 & 451 & 435 & 408 & 466 & 408 & 450 & 440 & 451 & 500 & 491 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Differential settlement analysis for quasi-3D scenarios. Figure 13: A closer look at the surface and elevation contours: scenario G1, year 40. The results of the three solids contents scenarios are compared in Figure 14A. As expected, the case S1 with 50% solids contents settles the most due to the higher volume of water that it contains and expels over time, compared to the cases S2 and S3. Figure 14B shows the same pattern of maximum settlement values for specific gravity experiments. In this case, the material with the highest Gs (S7) shows the highest settlement because it contains heavier contents (less bitumen), which tends to settle quicker than the other two cases S1 and S4. However, the maximum slope does not show a direct relation to the solids contents or the Gs. The results of tailings material scenarios can help in explaining the maximum slope results. According to Figure 15, the type of tailings material affects both settlement of the thickened tailings over time and the roughness of the final deposit surface. In fact, different constitutive relationship parameters (the A, B, C and D parameters in Equations (1) and (2)) will directly determine the settlement behavior of the material and indirectly the roughness of the final surface of the consolidated deposit. Among the numerical metrics of the surface differential settlements, slope analysis is an important consideration for closure landform decision making. Assessing the magnitude of slope grades offers insight into the potential future peaks, valleys, surface water flow and possibility for seasonal small and large pools of water. The visual analysis of the quasi-3D scenario results shows that the roughness of the final surface is more affected by the type of tailings materials, rather than the solids contents or the specific gravity. In order to analyze the slope distribution statistically, all the combinations of the points on the final surface are paired, and the slopes of the straight lines between all the pairs are calculated. Then, the slope values are sorted based on the straight distance between the points and grouped in 100-m classes. Figure 16 shows a sample slope distribution as box plots for one of the replications of case R1. The box plots show that the slopes are relatively steeper in short distances (smaller than 400 m).