Groundwater Quality Analysis in Nusakambangan Groundwater Basin/Indonesia

¹ Geological Engineering Department, Engineering Faculty, Diponegoro University, Semarang – Indonesia
² Master Program of Environmental Science, School of Postgraduate Studies, Diponegoro University, Semarang - Indonesia

Corresponding author: putranto@ft.undip.ac.id

Abstract

Nusakambangan groundwater basin is located in Nusakambangan Island, Cilacap Regency. Sea and swamp-bound the research area and there is no deep well, and the only one dug well available. This condition encourages the community to collect water from a pool of karst cave which unproven water quality. The study purpose is to determine the water feasibility at interest point as drinking water. The methods were hydrogeological field campaign by collecting 33 water sampling from pools and one sample from dug well to analyse physical and chemical properties as well as calculating the Water Quality Index (WQI). The results show the physical properties of water samples are having a relatively colourless but brownish in some samples, odourless, and a salty taste. The chemical properties indicated that the pH of water samples are ranging from 6,95 to 8,06 with the electrical conductivity (EC) start from 350 to 38,800 µS/cm. Moreover, the Total Dissolved Solids (TDS) have a value from 216 to 21,800 mg/L with the total hardness is around 134-5,395 mg/L. The water types are Ca-Mg-HCO₃ and Na-Cl. Based on WQI analysis, there are 13 unfeasible samples for drinking water in the south-east of Klaces village, in the western of Ujunggalang village, and in the Eastern of Tambakreja village.