INTERPRETASI LAPISAN BAWAH PERMUKAAN TPA MUARA FAJAR UNTUK MENGETAHUI POLA SEBARANAIR LINDI DENGAN MENGGUNAKAN METODE GEOLISTRIK KONFIGURASI WENNER

Abstract

Muara Fajar Landfill is one of the landfill sites in Pekanbaru City. This landfill is equipped with a leachate pond. In this area it is suspected that there is leachate seepage which is a waste pollutant that can contaminate the soil in the area around the landfill. Therefore, research is needed to determine the distribution pattern of leachate and analyze the structure of the subsurface layer at a landfill in order to obtain lithological feasibility in a landfill. One of the geophysical methods that is often used for lithological studies is the geoelectric method. The configuration of the geoelectric method used in this study is the geoelectrical method of the Wenner configuration. The wenner configuration aims to describe the vertical and horizontal variations of rock which will produce a cross section of resistivity in 2 dimensions. The measurement results obtained from the research location were in the form of resistivity data which was processed using the Res2Dinv software and interpreted into rock lithology. In the research area, measurements were made of 2 tracks with a track length of 100 meters. The depth reached using the Wenner configuration is 7.46 meters below ground level. On track 1 which is located at a depth of 2.25 meters has a resistivity value of <10 Ωm which is estimated as a leachate contaminated zone having a resistivity value of 7.09 Ωm. While on track 2 there is no layer estimated as leachate. The leachate- contaminated area found on track 1 comes from landfill leachate which is in the north to the southeast of track 1. The leachate is only found in one point of the area and no leachate distribution is found in other areas on the track. Therefore, the distribution pattern cannot be determined. Identification of rocks found around the Muara Fajar Pekanbaru Landfill include clay, gravel, and sandstone. This is agree with the lithological feasibility of a landfill.