ASSESSMENT OF A GROUNDWATER QUALITY FOR DRINKING PURPOSE IN ILORIN, NIGERIA

Abstract

Groundwater is a major source of water supply in Nigeria where there is an inadequate supply of water for domestic, industrial and agricultural uses. This paper examines the suitability of water samples from a target hand dug well (TW) in a residential area in Ilorin, Nigeria for drinking purpose. The samples were characterized to determine physico - chemical properties over eight weeks due to the observed, oily, greenish blue water discharged from the groundwater source. Another well in the neighborhood was investigated as a control (C). Concentration of selected anions, cations and the presence of hydrocarbons were established in the contaminated well with focus on nutrients and hydrocarbons related to sewer, paint and petroleum compounds to establish the possibility of leakages from sewers, the auto repair/painting workshop and the petroleum products pipeline which are located uphill of the well. The results of physico -chemical characterization carried out on the TW showed pH:7.3 – 7.9; turbidity: 1.2 – 4.5 NTU; total hardness; 175.30 – 222.02 mg/l; TDS: 90 – 125 mg/l. Concentration of cations and anions ranged between 0.16 – 0.24 for Fe; Mn: 0.01 – 0.06; Zn: 0.18 – 0.45; NO₃²-: 5.95 – 12.76; SO₄²-: 192.1 – 235.85;..