ABSTRACT

Water is very important to both the physiological and social activities of humans. However, human activities and natural factors have impounded its natural value. This study aims to evaluate the integrity of groundwater sourced from hand-dug wells in the Benin-Delta zones using different assessment techniques as a holistic model.

Data obtained were subjected to ANOVA (One-way Analysis of Variance) and DMRT (Duncan Multiple Range Test) was used to determine the significant difference where significant differences (P<0.05) occurred.

The results of this study showed that all the physical and chemical parameters in the hand-dug water were significant (P<0.05) across the studied stations. The findings from the multivariate analysis using the Principal Component Analysis revealed that there were characteristic variations of almost all the parameters assessed showing poor or excellent loadings across all the components. The Hierarchical Cluster Analysis showed that there was a similarity between stations 4 and 6, 3 and 9, and 5 and 7. The level of the bacteriological characteristics of the sampled hand-dug wells was within the safe limits. However, the range of values of the Total Bacterial Count concentration in station 4 was quite higher than the stipulated safe limits. The Pollution Index evaluations revealed that station 1 had the highest impact from Zn, Fe, and Pb. The Nemerow integrated pollution index value increased in stations 4, 5, 6, and 9 with Mn as the main impact in these stations. The health risk assessment of water from the HDWs showed that the level of heavy metals in the water cannot cause any non-carcinogenic health risk impact because the values were far lesser than the threshold stipulated. Meanwhile, the carcinogenic health risk characterization for Pb showed that there is a potential health risk if the water is consumed. The treatment of the hand-dug water by boiling and chlorination before drinking and for domestic purpose is highly encouraged to avoid any possible health complications.