Pollution potential evaluation of the Owerri water table aquifer in the urban environment
The likelihood of the numerous waste dumps in Owerri metropolis polluting the rich and prolific water table aquifer underlying the city is evaluated. Three prominent waste dumps located at three distant sites in the city were selected, and based on physical factors of depth to water table, sorption materials above the water table, aquifer permeability, water table gradient, and the horizontal distance between the source of pollution and the nearest well point was made. The results obtained in each case were weighed on LeGrand's rating chart of pollution potential and the aggregate points totaled 21.5, 24.0, and 21.0 respectively, corresponding to verdicts of very improbable potential for the aquifer. Although this method may not be perfect its results can serve as a guide. Efforts though should be encouraged towards making the situation of pollution of this aquifer more improbable.
Keywords: Pollution, waste dumps, water table, aquifer, urban environment, Nigeria