Multivariate Statistical Evaluation of the Hydrochemical Facies in Aba, Southeastern Nigeria

Abstract

The quality of groundwater in terms of physio-chemical and bacteriological characteristics in Aba was evaluated using multivariate statistical techniques. Six sources of pollutant were identified: Factor 1 (colour, conductivity, TDS, suspended solid, total solid and potassium), Factor 2 (chloride, calcium hardness, magnesium, calcium and total hardness), Factor 3 (temperature and total coliform), Factor 4 (nitrate and chlorine), Factor 5 (pH and iron) and Factor 6 (bicarbonate and sulphate). Factors 1, 2, 5 and 6 may be due to natural phenomenon arising from seawater intrusion, dissolution of bedrock, infiltration and chemical weathering respectively. Pollution coming from factors 3 and 4 can be attributed to human activities resulting from faecal contamination and fertilizer application respectively. These factors determine the hydrochemicalfacies of groundwater in the area. Controlled extraction of freshwater from the aquifer and a well-planned sanitary system is recommended for the area. The effectiveness of multivariate statistical techniques in the characterization of hydrochemicalfacies of the coastal plain-sand aquifers has been demonstrated in the study