STUDY OF HYDROGEOCHEMICAL AND GAS DISSLOVED OF GROUNDWATER AT BARAMBAI KOLAM KANAN VILLAGE, BARITO KUALA DISTRIC, SOUTHERN KALIMANTAN PROVINCE

• Main Author: Puspita, Meila
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/53317
• Institution: Institut Teknologi Bandung

This research was conducted in Kampung Bali, Barambai Kolam Kanan Village, Barambai District, Barito Kuala Regency, South Kalimantan Province. In 2006 and 2017, in the research area there were bursts of mud and gas during drilling wells. Based on field observations there are bursts of gas in the form of bubbles on a pond at the surface at the point of mud burst in 2006, and river in the research area. The objectives of research are to determine the hydrogeochemical condition and to know the origin of dissolved gases in water in the research area. The data used in this study was obtained from measurement results in the field and laboratory. Water samples consisted of one groundwater from a drilling well (BRB1), two river waters (BRB 2 and BRB 4), and one pond water (BRB 3). In field survey were done chemical-physical parameter measurements consisting of temperature (T), total dissolved solids (TDS), acidity degree (pH), and salinity. The measurement at laboratory was conducted using Ion Chromatography (IC), Inductively Coupled Plasma-Mass Spectrometer (ICP-MS), Gas Chromatography (GC), isotope ratio of oxygen-18 (? 18O), deuterium (?2H), and carbon-13 (?13C), and X-ray Diffraction (XRD). Results of data processing in this study were shown in Piper diagram, plotting graph of Molar Ratio Cl-/Br- to Cl-, plotting REE chart using PAAS and choncdrite standards, isotope graph ? 18O - ?2H, isotope graph ?13C, and rock mineral composition. Hydrogeochemical conditions in water indicate that surface water and rainwater in this research area are derived from meteoric water. The composition of stable isotopes ?18O and ?2H in groundwater of drilling wells indicates that the water come from a recharge area located far enough away with higher elevation with subsurface lithology of Dahor Formation. Based on the molar ratio of Cl-/Br- in groundwater, salinity is thought to be the result of biogenic processes of anthropogenic and urban effects. The composition of the isotope ?13C in groundwater (BRB 1) and gas pond water (BRB 3) is – 33, 65 - and -33.86 . Dissolved gas in groundwater (BRB 1) and gas burst of pond water (BRB 3) consist of CH4, CO2, H2S, O2, and N2. This assumes that the gas that comes to the surface in the research area is a biogenic gas.