ABSTRACT

This study was carried out to access the physicochemical, heavy metals, and microbial parameters in some selected boreholes of residential area proximal to an industry in Benin City, Edo State, Nigeria. Water samples were collected for a period of three months (July to September 2019). The physical and chemical parameters of the groundwater were obtained using standard methods and the mean values of each parameters ranged from TDS (17.67-58.30 mg/l), Alkalinity (0.00-2.67mg/l), magnesium (0.81-1.46mg/l), pH (4.43-5.20), electrical conductivity (33.33-110.00 mg/l), turbidity (0.00-0.33 NTU), S.S (0.67-1.33 mg/l), calcium (1.33-2.68 mg/l), hardness (6.67-12.64 mg/l), chloride (21.13-25.82 mg/l), sulphate (2.00-7.33 mg/l), phosphate (0.04-0.12 mg/l), nitrate (2.26-2.84 mg/l), D.O (3.95-4.83 mg/l) and B.O.D (0.35-1.37 mg/l). Heavy metals (Pb, Zn, Cr, Fe and Cd) were determined using AAS (atomic absorption spectrophotometer) and the values ranged from 0.002-0.014mg/l (lead), 0.16-0.37 mg/l (zinc), (0.02-0.03 mg/l) (chromium), and 0.17-0.30 mg/l (iron). Cadmium (Cd) was however found to be below detectable limit. Microbial analysis was done using pour plate method and the mean values ranged from tatal coliform (0.00-1066.67 cfu/ml), E.coli (0.00-366.67cfu/ml) and mesophilic bacteria (733.33-4066.67cfu/ml), Faecal streptococci was found to be below detectable limits. World Health Organization (WHO) acceptable limits were used in the evaluation. Some of the parameters were within World Health Organization (WHO). Water Quality Index (WQI) values ranged from 21.42 to 26.63 indicating excellent and good water quality.