Abstract
This paper deals with interaction between ground water and an adjacent river. The interaction is described quantitatively by chemical mass balances (CMBs) which is the most widely used receptor model. Ground water and river upstream and downstream samples are tested for seventeen parameters to determine the ground water underflow rates to the river by using the CMBs. Also electrochemical compositions of major ions for each samples are analyzed to provide the characteristics of each water. Through the analyses for overall compositions between ground and river waters, the impact of ground water underflow to the river quality is evaluated.