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Multivariate factor analysis (FA) by principal components reduction and varimax rotation techniques were employed to reduce bulk hydrogeochemical data from Iju Community, Southwestern Nigeria into components that explain possible underlying structures existing among the variables. This is with a view to characterizing groundwater chemical facies in relation to underlying hydrogeochemical processes suppossed to be responsible for any variation in water quality. Thirteen water quality variables were investigated at 38 sampling points. The data obtained were standardized to ensure normal distribution and then subjected to factor analysis by principal component extraction method with varimax rotation and Kaiser normalization. The criterion of eigenvalues greater than 1.0 and indications from the scree plot informed the extraction of two components which together explain 83.73 % of the total variance in the dataset. Component 1 with high loadings of TDS, EC, Temperature, Total hardness, Ca, Mg and Cl explains  46.70 % of the total  variance. It represents the dissolution-precipitation (exsolution) process involving water-rock and water-soil interactions, which are predominantly silicate mineral weathering processes. Component 2 with high loadings of  pH, K, Na, HCO₃, Alkalinity and SO₄ explains 37.03 % of the total variance, reflecting geological and hydrogeological controls by oxidation and speciation reactions. Water in the area was classified as Na⁺- K⁺ - Cl^-, Na⁺ - K⁺ - Cl^- - HCO₃^- and Na⁺ - K⁺ - Cl^- -SO₄^2-  water types.