Water infiltration rate of illegal mining sites in Bukit Soeharto Forest Park, East Kalimantan Province

Abstract

Infiltration is a component of the hydrological cycle which functions as a source of groundwater, minimizing flooding and distributing water evenly throughout the rainy and dry seasons. This study aims to determine the rate of water infiltration or infiltration and permeability values in 2 (two) land conditions for ex-illegal mining sites, namely at KM 68 and KM 48, and the location of undisturbed land in KM 54 secondary forest area of the Bukit Soeharto Forest Park (BSFP). The research method used a double ring infiltrometer, then tested at the Kalimantan Bioresources Laboratory. Infiltration rate shows that secondary forest area of the KM 54 location was 275.2 mm/hour which was included in the very fast class, while in the former mining sites KM 68 and KM 48 respectively it was 244.6 mm/hour, and 145.7 mm/hour which is included in the fast class. Laboratory analysis shows that the soil permeability value in the secondary forest area of KM 54 location was 6.41 cm/hour which was included in the rather fast class, while the permeability value in the ex-mining land area of KM 68 and KM 48 respectively was 6. 26 cm/hour and 3.66 cm/hour which are included in the medium class. This is due to the physical soil properties such as soil texture, soil structure, bulk density, and soil porosity which are the factors that cause differences in infiltration rates in several land conditions.