“Determination Of Some Physoco-Chemical Parameters And Haevy Metals In Drinking Groundwater From Burayu Town, Oromia Regional State, Ethiopia”

Abstract

Groundwater is one of the most important sources of drinking water in Ethiopia. Hence, it is important to assess the quality of these water sources as it might be contaminated by various human activities. The main purpose of the study was to assess some physico-chemical water quality parameters in ground water sources used for human consumption in Burayu town, Shager City, Oromia regional state, Ethiopia. Samples were obtained from seven (Sansus, Stadium, Tatek, Masgid, Chafe, M/Iyesus and Industry) sampling sites for physic-chemical parameters and heavy metals analysis during the dry season. A wet digestion procedure using mixtures of 2.0 ml of HNO3 (69 - 72%), 1.0 ml of HCl (37%) and 0.5 ml H2O2 of (30%) solution was employed prior to flame atomic absorption spectrometry (FAAS) analysis of Mn, Cr, Cu, Ni, Cd, Pb and Zn. The accuracy of the procedure was evaluated by analyzing the digest of the spiked samples and the percentage recoveries which varied from 90.14 to 97.18%. The levels of the selected physicochemical parameters of the groundwater were found to be: EC, turbidity, temperature, pH, TDS, alkalinity, PO4 3-, SO4 2-, NO3 -, Cl-, Ca, Mg, and total hardness. Similarly, the mean concentration results of the studied heavy metals were in the range of (mg/l): Fe, Mn, Zn, Cu, Cd (ND), Ni (ND), and Cr (ND). Pb was below the method detection limit in all the sampling sites. A comparison of the measured parameters with the national and international standards set by EDWQ (2010) and WHO (2008) shows that all the parameters measured were below the maximum standard permissible limits. This indicates that the groundwater was less contaminated and therefor suitable for drinking purposes. However, continuous monitoring of these studied parameters and other physicochemical and biological parameters are vital to keep the health and safety of the consumers.