Abstract

The water quality assessment of some ground water supply to a school in Ilorin City was carried out over a year. The concentration of nitrates in the samples were determined using a UV - visible spectrophotometer. The wells located within the student hostels were found to be high in nitrate with concentrations ranging from 7.11 - 8.54 mg/l. This is close to the World Health Organization (WHO) limit of 10 mg/l allowed in drinking water. The concentrations in the boreholes ranged between 0.43 - 1.34 mg/l. The trace metal analysis was carried out using Atomic Absorption Spectrophotometer. Lead (Pb) and cadmium (Cd) concentrations were found to be below detection limit. The concentration of copper (Cu) ranged between 0.017 - 0.065 mg/l, the concentration of magnesium (Mg) ranged between 4.29 - 16.28 mg/l while calcium (Ca) concentration ranged between 26.60-235.60 mg/l. The metal concentrations were all within WHO recommended concentrations in drinking water. A linear regression carried out using the polymath software gave a negative slope.

Key words: Water quality assessment, leaching, UV visible spectrophotometer, polymath software, linear regression.