The interrelationship between ISTN lake, Babakan lake and the surrounding wells of shallow groundwater using stable isotopes δ ²H and δ ¹⁸O for the lake bank filtration potential

¹ Department of Civil Engineering, Institut Sains dan Teknologi Nasional, Jakarta, Indonesia
² Hydrology Section, National Nuclear Energy Agency, Jakarta

^* Corresponding author: syafalni.s@istn.ac.id

Abstract

The investigation of the interrelationship between shallow groundwater and lake water is one of the important characteristics in groundwater basin research. An understanding of the location properties can be used for the lakebank fitration pontential evaluation. The objective of this research was to describe the interrelationship of shallow groundwater and the lake water from ISTN lake and Babakan lake. An effective tracer in groundwater basin research can use the environmental isotopes method for revealing the interrelationship between lake water and surrounding shallow groundwater. This research was conducted by taking samples of shallow groundwater from the surrounding wells around the ISTN and Babakan lakes. Based on isotopes δ ²H vs. δ ¹⁸O results, the shallow groundwater of the surrounding wells originated from the lake water. The results were verified with a student test distribution using 95% confidence level which showed that all samples were in one cluster. From the analysis of Total Dissolved Solids (TDS) of the samples locations, all of the samples were in range of fresh water but the pH of some samples was lower than the pH requirement for drinking water, so the pH should be improved before consumption.