By Eluozo, Solomon Ndubuisi
Model studies of groundwater quality and formation characteristics in phreatic aquifer were carried out in Rivers State the study area. The research was to find a better solution of pollution transport in groundwater, considering the effect of geologic parameters such as heavy metals, micronutrients, porosity, permeability, and void ratio. The source of pollution was through indiscriminate dumping of biological wastes and wastes from soakaway, regenerating the wastes in most parts of the study area. This research was carried out through an experiment performed for E.coli transport, including some other parameters that influence microbial growth, inhibition and variation for fast migration within a short period of time. These parameters are heavy metals, micronutrients, permeability, porosity, and void ratio. Velocity of solute transport (E.coli) was determined through column experiment in each soil sample for all the locations. Empirical model was applied through experimental results plotted, generating a polynomial equation. The expressions from polynomial were applied to verify the results for E.coli, micronutrients, heavy metals, degree of porosity, permeability and void ratio. The physiochemical parameter from the study carried out found that the growth of E.coli under environmental conditions favoured it. The research was able to produce the level of physiochemical parameter influencing E.coli concentration in groundwater. The presence of E.coli depends on the availability of nutrients as well as favourable conditions in terms of physiochemical parameter. More so, the concentration increased with depth in micronutrient. The study confirmed that the higher the depth of water, the lower the population of E.coli in some locations based on the decrease in substrate utilization; while in some areas, it varies. The study explained that the rapid growth on the population of E.coli is experienced when the pH value is acidic than alkaline. The study carried out was able to express the stabilization of groundwater quality by inhibiting the presence of metallic element in some locations; while in few locations in the study area, it was discovered that the presence of E.coli in different aquifers have lower percentage and become less harmful to the quality of groundwater for human utilization. The level of porosity were investigated on the migration of E.coli influenced by porosity from one aquifer to the other, the results were calibrated and verified generating a model that can be applied to predict the rate at which E.coli transport within a short period of time. The variation of micropores i.e. void ratio from different soil depositions were determined, calibrated and verified. The results can be applied to predict the variations in the micropores and hydraulic conductivity within the soil structure, as it influences the variation in the migration of E.coli in phreatic aquifers. The rate of liquid flow within the soil profile (stratum) i.e. through the rate of permeability, is imperative because it has contributed to the rate of distribution of E.coli, as well as effectiveness in terms of stability in the region by reducing the migration and transport at different strata, this was investigated in the study. The results on the level of flow and the influence on the permeability were determined in the study areas. The permeability results were verified to predict the rate of velocity of water like that of solute at different soil formations, this results verified can be applied to predict the velocity of ground water influencing the rate of transport at different strata, the verified model result can be applied to predict the time at which the microbes can transport to groundwater aquifers in all the study areas. The soil compositions influenced by E.coli concentration as well as the rates of migration were investigated, the soil profile that contains high concentration known to be gravel and coarse were determined. Finally, the developed model from experimental results should be applied by thorough assessment of the area, to determine the type of concept to be applied in assessment of ground water quality in the study location through design of boreholes.