Abstract

Groundwater composition can be altered significantly due to geogenic and anthropogenic inputs from bedrocks and human activities respectively. Such impacted water may be injurious to health if consumed. Water quality depends on the physical, chemical and bacteriological composition of water. Hydrochemical assessment of groundwater within Afe Babalola University (ABUAD) and its adjoining environments was undertaken with the aim of determining its chemical composition and suitability. A total of 26 boreholes were sampled randomly within ABUAD during the dry stable weather condition. Two set of samples were collected from each sampled borehole one for anions and the other one for captions and heavy metals. The water samples were analyzed for heavy metals, cations and anions using Atomic Absorption Spectrometry, Flame Photometry Emission and titration method at the Department of Geology, and Multi-Disciplinary Research Center, University of Ibadan and National Geo-Hazard Research Center, Ibadan respectively. Results obtained were subjected to statistical analysis and qualitative evaluation to determine the quality of the groundwater. The results of the analyses showed cations (major and trace elements) variations in mg/l; Ca²⁺ (14.0 - 69.0), Mg²⁺ (20.0 - 62.3), K⁺ (0.1 - 42.5), Na⁺ (12.3 - 54.0), Pb²⁺ (<0.01 - 3.93), Cu²⁺ (1.00-0.43 mg/l; Cd²⁺ (1.00 - 5.80), Co²⁺ (.01 - 3.86 mg/l) and Cr²⁺ (.01 - 3.79 mg/l) while anions variations in mg/l HCO₃^- (4.6 - 26.8 mg/l), Cl^- (60.0 - 180.0), NO₃^- (<0.01- 2.8 mg/l) and SO₄^2- (0.6 - 4.7 mg/l). The concentrations of anions and major cations in most of the investigated boreholes were found to be chemically conformable with WHO standard for safe water. However, most of the trace elements with exception of Cr and Co were found to be significantly higher than the WHO standards for safe water.

Key words: Groundwater, hydrochemical assessment, Afe Babalola University, Ado-Ekiti (ABUAD), geogenic, anthropogenic.