Assessment of Leachate Infiltration From Piyungan Landfill Using Electrical Resistivity Method

摘要

Piyungan Landfill (TPA) is the largest landfill located in Bantul Regency of Yogyakarta. Leachate samples collected around the landfill area indicate that there is a contamination of groundwater around the landfill. This study has been successfully found a leachate infiltration to the soil layer at the north area of the landfill, which is the flow direction of the groundwater flow from the landfill. Electrical resistivity (ER) measurement towards fluid-saturated soil was carried out in the laboratory. Soil samples were saturated with fluid aquades-leachate and ER values were measured. ER value gained for saturated sandy clay with total dissolve solid TDS 10 mg/l to 350 mg/l is between 6.8 Ωm - 9.7 Ωm. Measurement of geo-electric resistivity 2-D of multi electrode Wener Schlumberger configuration has a minimum distance of 5m with an expanse length of 190 m. It is geo-electric line is 300°NW at the point X = 437.172m; Y = 9130495m; Z = 73.5m. This line perpendicularly cut the fault line at point 110m, and cross the Banyak River flow at point 135m. ER values of soil layer obtained from the results of geo-electric interpretation RES2DINV were ranged from 2 Ωm - 120 Ωm. At point 135m of the eastern part, ER value is between 2 Ωm to 10 Ωm with a depth of 10-12 m. This layer is estimated as a layer of Sandy Clayey saturated with contaminated water by leachate from Piyungan Landfill. ER value under point 40m to 130m is between 2 Ωm -12 Ωm with a depth of 15m, which is estimated as a layer of Tuffaceous Clay Sand Stone.