#TITLE_ALTERNATIVE#

• Main Author: MARYA NOVITA (NIM : 22110305), DIAN
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/20024
• Institution: Institut Teknologi Bandung

With its low pH and high solubility of metal, AMD was accumulated in pit which could not be 100% backfilled, leaving ahuge pit with excessive exposure of air and rain water and therefore, numerous amount of AMD. Preventing its generation is more important and useful for long term act. A study to characterize the rock in pit and its acid generation process is needed for the geochemical modeling. Rock samples from unsubmerged pit wall were collected together with some water sample from existing pit lake. Rock samples were prepared and subjected to geochemical characterization test including static test, kinetic test and mineralogy test. While physical and chemical characteristic of water samples were measured. <br /> <br /> <br /> Among 8 rock samples collected from pit L1, only 2 samples considered as PAF low capacity. PHREEQCI2 simulation was done on laboratory kinetic test’s samples (L1-B02, L1-B03, L1-B04 and L1-B07) and obtained high accuracy in its simulation and gave pyrite mol transfer of 3,05E-06 to 3,23E-04 mol/L. Simulation was proceed to a bigger scale: pit lake Due to the possibility that samples were not highly represent the whole pit rock, an addition was made on high PAF rock sample which is taken from another pit: E1R09. This sample was subjected to all tests previously done for samples from pit L1. Simulation was begin with a mixing from all samples in kinetic test and rain water with mixing ratio of L1-B02 : L1-B03 : L1-B04 : L1-B07 : E1-R09 : rain water were 0,57 : 0,58 : 0,4 : 0,7 : 0,47 : 1. A mixing water quality had nearly same characteristic with existing pit lake water. In this pit lake scale, the pirit mol transfer reaches up to 4,75E-02 mol/L. However, this mol transfer value has low accuracy due to incapabilityof PHREEQCI2 simulation to perfectly describe the complecity of pit lake including the rock physical characteristic, porosity, water permeability, oxygen diffusion and the possibility of further reaction on submerged pit wall.