Hydrogeochemistry characteristics of groundwater and its suitability for water supply and irrigation in Jilin City, China

Groundwater is the most important water resources in modern water supply, and its quality is the determining factor, especially for the groundwater supply under extreme events. Groundwater quality survey has been carried out in Jilin City, which is a famous industrial city in northeast China. The results show that (1) the distribution of major ions in the groundwater is as follows: Ca2+ > Mg2+ > Na+ > K+ and HCO3- > SO42- > Cl-> NO3-; the Piper's, Gibbs's, and Langelier-Ludwig's diagrams suggest that groundwater was evolved due to the water-rock interaction; (2) geochemical relations (Ca/Mg ratio, Ca + Mg versus HCO3 + SO4, Na versus Cl) suggest that the dissolution of carbonate minerals gypsum and halite is the significant mechanism dominating the groundwater chemistry, the relations also suggest that the ion exchange is the secondary processes for higher concentrations of Ca2+ and Mg2+ ions; (3) the influences of agricultural fertilizers and irrigation practice are the other reasons for increasing NO3-ions in the groundwater; according to the drinking water quality standards, the groundwater is not suitable for drinking with reference to the concentrations of total hardness, Ca2+, Mg2+, NO3-, F-, and Fe in many locations; (4) based on the parameters mentioned (sodium adsorption ratio, Kelly's ratio, sodium percent, permeability index, and magnesium hazard), the groundwater quality is assessed and the overall irrigation qualities of wells are demarcated as suitable for irrigation.