IDENTIFICATION OF HEAVY METAL ARSENIC (As) IN SHALLOW GROUNDWATER USING KRIGING METHOD (Case Study: Shallow Groundwater of Ciwidey Sub-watershed)

• Main Author: AMIRATUL AFIFAH NIM : 25316003, NUHA
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/29752
• Institution: Institut Teknologi Bandung

Arsenic is a toxic trace element that can cause various negative impacts on human health. One of arsenic exposure source for humans is through groundwater. One of groundwater indicated with high arsenic content, is groundwater in a location affected by geothermal systems. Arsenic contamination in groundwater is a serious global problem and arsenic contamination in groundwater has occurred in Taiwan, Chile, Bangladesh, Argentina, Mexico, China and India. Ciwidey Sub-watershed is an area on Mount Patuha slope located in the south of Bandung Basin has many geothermal manifestations which is one source of volcanogenic pollutant, including arsenic. A study conducted on 42 shallow groundwater samples in Ciwidey Sub-watershed showed that arsenic concentrations ranged from 0.001 mg/L to 3.25 mg/L, exceeded the safe limits established by WHO and Indonesia . The geostatistical kriging method is used to estimate arsenic concentration in non-sampling sites and to know the pattern of arsenic distribution. Geostatistical methods with Simple Kriging without transformation provide the most accurate prediction results for arsenic distribution. The highest arsenic concentration is found in the hot springs of Patuha Mountain’s geothermal manifestation and the pattern of arsenic distribution decreases towards the center, but there is an increase of arsenic concentration in the downstream of the research area. Interpretation of arsenic presence based on groundwater geochemical analysis using Schoeller Diagram shows the result that groundwater at the study site comes from the same source, which is influenced by geothermal system. The public service along the Ciwidey Sub-Watershed by PDAM is only 19.75% and 80.25% uses shallow groundwater as a source of drinking water.Thus, an estimated 430,600 people are at risk of exposure to arsenic contamination in shallow groundwater beyond the safe limits established by WHO.