Assessing the Heavy Metal Content in Shallow Hand Dug Well Waters to Determine Water Quality in Okpuno-Awka, Southeastern Nigeria

Shallow hand dug well water is the main source of water supply for the local population in Okpuno-Awka area. This study investigated the effects of heavy metal pollution on natural water sources in Okpuno-Awka of Southeastern Nigeria by conducting a geochemical assessment of contaminants from dumpsite leachates. Samples within the proposed influence zone at which the leachates can contaminate the natural water sources were targeted. These include samples collected from hand dug wells, surface waters at about 300m-1000m away from the dumpsite and some leachate samples collected at the dumpsite. Laboratory analysis was conducted on the water samples to determine the levels of heavy metals, following established standard methods. These heavy metals include iron (Fe3+), manganese (Mn+), Lead (pb+), Arsenic (Ar), Cadmium (Cd), Chromium (Cr3+), Cobalt, Zinc and Nickel (Ni). The presence of various heavy metals measured suggests a diverse range of waste materials that points to the source of Pb, Zn, Fe, Cd, Cr and Mn. The results from the analysis showed that the observed concentrations of Fe in borehole water samples ranged from 0.016 mg/l (BH 2) to 0.216 mg/l (BH 12) while Manganese varied between 0.009 and 2.142 mg/l. Arsenic for hand dug well samples ranged from 0 to 0.078mg/l. Some other parameters were within the permissible limits of regulatory standard for drinking water. The quality of water in the metropolis has therefore been grossly affected as the heavy metals present in them have rendered the water unsafe and unhealthy for consumption and therefore should not be consumed without proper treatment