PHYSICAL MODELING OF GROUNDWATER FLOW IN ARTIFICIAL AQUIFER USING SANDBOX

• Main Author: Frengki, Rahmat
• Format: Theses
• Language: Indonesia
• Subjects: Karya Umum
• Online Access: https://digilib.itb.ac.id/gdl/view/44021
• Institution: Institut Teknologi Bandung

Excavation and dumping activities of overburden material can expose rock containing sulphidic mineral which in turns reacts with oxygen and water to form acid mine drainage. To limit exposure of this rock to atmospheric air and producing acid mine drainage, it is necessary to take prevention measurement by PAF/NAF material segregation and encapsulation of PAF material inside NAF material in disposal area. Mismanagement of dumping can cause these material mixed unevenly and increase the potency of AMD producing. In order to reduce/limit the production of AMD, saturation of dumping material can be selected as an option. This option is also can be rgarded as artificial aquifer formation. This study aims to determine controlling variable of artificial aquifer system in order to maintain saturated steady-flow condition and piezometric head above aquifer layer using laboratory-scaled sandbox. Dimension of sandbox are 120cm, 90 cm and 90 cm for length, depth and height, respectively. Confined aquifer is constructed within the sandbox using silica sand as aquifer layer and clay as confining layer. Silica sand as aquifer layer has physical grain size of -20# +30# mesh with hydraulic conductivity of 3.3 x 10-4 m/s. In the other hand, clay as confining layer has hydraulic conductivity of 5.54 x 10-7 m/s. The thickness of silica sand is 37 centimeters, whilst thickness of clay is 18 cm. Within the system, 6 observation wells are constructed. Numerical model simulation verified with physical model shows that saturated steady flow condition can be obtained by maintaining input and output flow of the system. To maintain the system, allowed input flow based on the model varies from 0,024 – 0,033 litre/s with output flow varies from 0,022 – 0,033 litre/s