ESTIMATION OF ANISOTROPIC HYDRAULIC CONDUCTIVITY AT GRASBERG OPET PIT MINE AREA, PAPUA

• Main Author: Hermawan Yosandian - NIM : 22715004 , Hazmanu
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/27785
• Institution: Institut Teknologi Bandung

<p align="justify">The main aquifer which is located in research area (Grasberg open pit mine, Papua) is fractured media, that is commonly known for its complexity and anisotropy, especially for hydraulic conductivity (K) value. This brings problem in hydrogeological modelling, used for dewatering. Furthermore, K value measurement can only be conducted in few places, comstrained by time and money budget. The best solution is accurate estimation of K value need to be acquired at unsampled places, particularly at below surfaces. <br /> <br /> This research uses Oda and HC-system methods to estimate K value at surface and below it. For combining these methods, it needs subsurface fracture characteristics modelling based on DFN and transect concepts. 13 slugtest points are used for estimated K results verification. The fracture parameters needed for this estimation purpose are trace length, aperture, orientation, DI, RQD, LPI, and GCD. All these parameters are used for input in ANFIS training, a soft computing method. Meanwhile, Oda method results (Kxx, Kxy, Kyy) become the target (output). Then correlation between model results and field data will be compared. ANFIS model made a good estimation with R2=0.85, compared to the other methods. <p align="justify">