Analysis for measuring the interaction of groundwater and river water by using Radon-222: A case study in Yangsu-ri, Korea

The water cycle is essential for the maintenance of ecosystems. Above all, water exchange between groundwater and river water has a significant impact on the water quality and hydrological zones. The natural radiogenic tracers such as Radon-222 can be used as good indicator for measuring the interaction between groundwater and river water even though the conventional methods of analysis are direct measurements of water flux, heat tracer methods, mass balance approaches and methods based on Darcy's law. The object of this study is to know the change of water environment and to do water resource management effectively by studying the interaction between groundwater and river water in Yangsu-ri of Korea. This paper used methods using temperature profiles, EC values, DO values and radon tracer. In this study, diurnal and seasonal variation of radon value was measured with other values. The result values proved that the more the region was influenced by river water, the closer to the values of river water the result values are. The radon value indicated a similar pattern with other values. The analysis also applied river water stage change by dam discharge. In addition, the mixing modeling of groundwater and river water was conducted to confirm the difference between the calculated value and the measured value. It turned out that radon tracer can be used as environmental tracer for analysis of the interaction between groundwater and river water.