SIMULATION OF THE EFFECT OF HIGH INUNDATION CHEMICAL SOLUTION ON THE STABILITY OF HEAP LEACH

• Main Author: Nabella, Andromeda
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/69083
• Institution: Institut Teknologi Bandung

PT XYZ is a gold mining company that uses static heap leach to separate precious metals from their rocks. The heap leach mechanism of the static type is to accumulate fresh ore material (before leaching) on top of spent ore material (after leaching) for irrigation. This mechanism continues, the fresh ore material will be piled back on top of the spent ore layer so that a higher ore pile is formed. Fine material ore that fell during the irrigation process can fill the voids between F2 material which causes the chemical solution to not be able to continue to the drainage pipes under F2 material. This causes the chemical solution to be trapped in the body of the heap leach. The modeling of chemical solution inundation height in this study was carried out based on the heights of 2 VWP monitoring points, namely VWP 12 & 13. The purpose of this study was to determine the effect of inundation height on the stability of the heap leach body. The analysis was carried out by simulating the height of the chemical solution pool with the boundary equilibrium method using Slide2 software. The results of this study indicate that high chemical solution inundation at elevation 44.39 for VWP 12 and 70.18 for VWP 13 causes heap leach in unstable conditions indicated by FK = 1.058 and POF = 27%. This is justified based on the validation results which show the similarity between displacement RS2 and displacement monitoring prism HLO-4. The analysis also shows that after the repairs and handling carried out by PT XYZ by installing horizontal drainage on lifts 1 and 2, installing geomembranes above lift 5 and making buttresses at the foot of the existing heap leach pile, it has improved stability with FK = 1,980 & POF = 0% for surface failure along the addition of the old geomembrane and FK=2008 & POF=0% for surface failure along the old geomembrane.