Influence of hydrogeochemical processes and assessment of suitability for groundwater uses in Busan City, Korea

Abstract

This study was carried out to understand the hydrogeochemical processes of groundwater quality and groundwater use in the Suyeong District of Busan city, Korea. Groundwater samples were collected from 40 wells in February, 2010. The abundance of major cations concentration in groundwater is Na+ > Ca2+ > Mg2+> K+, while that of anions is Cl− > HCO3− > SO42− > NO3− > F−. According to hydrogeochemical facies, Ca (HCO3)2, Ca Cl2 and NaCl are the dominant groundwater types in this study area. Mechanism controlling the water chemistry (Gibbs) indicates that most of groundwater samples fall at rock-weathering dominance zone. The geochemical processes and temporal variation in groundwater in this area are influenced by evaporation processes, ion exchange and dissolution of minerals. According to water quality index (WQI) of the study area exhibits 8 % of the groundwater samples fall at the unsuitable zone for drinking purpose. The spatial distribution map of WQI shows the poor quality of the water decrease toward the southern part of the study area. The results of SAR, Na%, PI, RSC and MH show that majority of groundwater samples are suitable for domestic and agricultural purposes. By the hydrogeochemical analysis, aquifer rock weathering, seawater intrusion, sewer leakage are the dominant factors that determine the major ionic composition. The proper management plan is necessary to preserve valuable groundwater resources.