Impact of Topographic Change against Groundwater Recharge Areas Caused by Limestone Mining in Rengel District, Tuban Regency

Abstract

Exploitation of limestone in Tuban Regency has been carried out continuously with a very large amount of production. In one area of 12 hectares mining site alone can produce more than 290.000 tons per year, this condition leads to significant change in the topography of the mining area. In this study, research was conducted to the impact of changes in topography, which results to the change of broad, shape, and the ability of water recharge areas that lead to the groundwater reserve. The primary data used is the amount of mined limestone produced by PT. Pentawira in researched site and DEM (Digital Elevation Model) satellite imagery. In addition, the supporting data used are characteristic of limestone and the reserve data of groundwater in Tuban Regency. Analysis of DEM satellite imagery, presents the model of geomorphology and topography of the study area, and then combined with mining data provided by PT. Pentawira to create a model or simulation of topography changes in the mining site, and how much impact it produce to the groundwater recharge areas including the reduce ability of recharge areas in the research site to absorb meteoroids water, that it is known after conducting the research that from 2013 forward the absorbance ability is reduced to more than 31 million liters per year. The analysis result of the study in this research can be used as a reference for the government in arranging environmental impact assessment for limestone mining companies. Mining activity will be controlled if the environmental impact assessment is done correctly, so that both environmental balance and sustainability can be maintained. The research site was conducted in Rengel District, Tuban Regency, East Java.