Statistical Analysis for Understanding Groundwater Chemical Variations

Understanding the hydro-chemical variation of groundwater is important for water usage in the coal mines. In this study, twenty-one and eleven samples have been collected from the coal bearing and limestone aquifer systems, respectively in a coal mine in northern Anhui Province, China. And their major ion concentrations have been analysed by statistical methods including correlation, factor and cluster analysis. The results indicate that the hydro-chemical characteristics of the groundwater samples from these two aquifer systems are different, the groundwater samples from the coal bearing and limestone aquifer systems are dominated by Na-HCO₃ and Ca-HCO₃ types, respectively. Correlation and factor analysis, as well as traditional hydro-chemical methods indicate that dissolution of evaporates and carbonates, as well as weathering of silicates are contributors for the chemical variations of the groundwater samples. In combination with traditional methods, the study demonstrated that statistical analyses are useful tools for understanding the hydro-chemical variation of groundwater.