Modelling the Spatial Distribution of Heavy Metal Pollution in Groundwater System Near Selected Waste Dumpsites in Rivers State

This study was focused om development of model for the prediction of heavy-metal pollution ingroundwater sample near waste dumpsite in selected communities in Rivers State. Two waste dumpsites in Choba and Aluu communities in River state were randomly sampled. Boreholes were sampled at distances of 50m, 100m and 150m away from the dumpsites and a control sample was collected at 300m away from the dumpsite. Groundwater samples were collected from the boreholes and taken to laboratory for identification of presence and concentration of the heavy metals. The results of the analysis revealedeight different heavy metals in the water samples namely, Copper, Mercury, Barium, Cadmium, Chromium, Iron, Lead and Zinc.Model were developed using Excel to expressed the relationship between the concentration of the heavy metal and their distances away from the dumpsites. The models revealed that there is inverse relationship between concentration of the heavy metal and distance of sampled location from the dumpsites in both locations. In Aluu, the results revealed that the percentage deviation between model-calculated values and actual values for copper, mercury, barium, chromium and iron were 11.00, 8.30, 6.00, 8.75 and 15% respectively. However, the model-calculated values for cadmium, zinc and lead were negative which suggest that 300m is outside the active zone of the heavy metals originating from the dumpsite,meaning that the concentrations of cadmium, zinc and lead obtained at this distance did not originate from the dumpsites. In Choba, the results revealed that the percentage deviation between model-calculated values and actual values for copper, barium and lead were 6.00, 9,80 and 6.67% respectively, However,model-calculated values for chromium, cadmium, zinc, mercury and iron were negative which suggest that 300m is outside the active zone of these heavy metals originating from the dumpsitewhich also means that the concentrations of chromium, cadmium, zinc, mercury and iron obtained at this distance did not originate from the dumpsites. It was concluded that the models are significantly suitable for the prediction of heavy metal pollution with respect to their distance from dumpsite