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A long essay or dissertation or thesis involving personal research, written by postgraduates of University of Ghana for a university degree.
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Item Effect Of Insanitary Conditions On The Physico Chemical Quality Of Groundwater In Select Coastal Communities In Keta(University of Ghana, 2013-07) Norvivor, F.A.Groundwater issues in coastal communities are usually associated with seasonal salinization, due to sea water intrusion and seasonal flooding, however the main objective of this study was to assess the physical and chemical water quality of hand dug wells in Atorkor, Srogbe and Whuti, which are located close to possible contamination sources and further from these contamination sources. Thirty selected hand dug wells in households were used for this study. The uses, dependency, knowledge on possible contamination sources and some aesthetic parameters for water quality were assessed. Important physico chemical water quality parameters namely, pH, temperature, turbidity, TDS, TSS, hardness, conductivity, Nitrate, Phosphate, Sulphate, Calcium and Magnesium were assessed and compared with WHO guideline values for drinking water quality. Results from this study showed that, there were possible contamination sources of groundwater in each of the three communities. The local people depend on groundwater abstracted from hand dug wells for domestic purposes such as cooking, washing, and drinking. The study also found out that they had very little knowledge on possible contamination from the identified sources; this was also confirmed by the fact that, they did not treat water before using it for drinking purposes and the fact that, they did not ensure strict sanitary conditions around well head. Physico chemical water parameters analyzed on hand dug wells all wells in Srogbe, Whuti and Atorkor recorded relatively high concentration of conductivity, turbidity, TDS, TSS, Hardness, Calcium, Magnesium and Phosphates, irrespective of their proximity to potential contamination sources. Nitrates however, were low in all sampling points. Only Phosphate was also particularly high near a specific contamination source. Microbiological analysis, done on some selected wells also showed that irrespective of proximity of contamination sources, microbial contamination was still evident. Therefore, irrespective of the proximity to potential pollution sources, physico chemical water was not significantly affected.Item Hydrogeological Assessment of Groundwater on Legon Campus: Application of Geophysical and Numerical Techniques(University Of Ghana, 2015-07) Bosompemaa, P.The hydrogeological conditions of University of Ghana, Legon Campus was assessed using geophysical and numerical techniques. Data from borehole lithological logs and electrical resistivity survey was used to conceptualize the hydrogeological system of the terrain whiles using MODFLOW to generate groundwater flow simulation models under steady state conditions. The objective of the study was to conceptualize the hydrostratigraphy through geophysical techniques, develop a groundwater flow geometry for proper understanding of the mechanisms of groundwater flow in the area and to estimate groundwater budget and the responses of the aquifer system to stress. The calibrated steady state model together with a stochastic approach was used to simulate some scenarios of groundwater resource and its management in the area. The results of the study suggested three main lithostratigraphic units from geoelectric sections and the stratigraphic model and these units are phyllite, quartzite and laterite from the bottom to the top. Based on the borehole logs, the pseudo- sections and the geology of the area, the aquifer was encountered at a depth of about 38 m to 60 m which is attributed to probably the moderately weathered phyllite or quartzite giving an aquifer zone of thickness 22 m and this could be variable in space. The result suggests the dominance of local groundwater flow systems which results from the local changes in topography and hydraulic conductivity field. The estimated hydraulic conductivity values range between 4.0 m/day and 60.0 m/day and this is probably attributed to the local changes in the degree of weathering and/or fracturing in space. The estimated groundwater recharge ranges between 0.008 m/yr to 0.12 m/yr with an average of 0.064 m/yr representing 1% and 15%, with an average of 8.1% of the annual precipitation of 0.7 m in the area. The amount of water that entered the aquifer system through the general heads is 368368.08 m3/d and this is due to changes in the hydraulic heads and the interconnectivity of the system with other aquifer systems. The contribution of recharge to the water budget seem low because the vertical percolation of rainwater is restricted due to the clayey nature of the terrain and the many physical developments which are seen on the Legon Campus. From the scenario analysis that were performed, decrease in recharge did not have any significant change on the groundwater water system. However, when the initial abstraction rates were increased up to about 50%, dry cells were observed around some of the wells.Item Analysis Of Groundwater Abstraction Scenarios In The Kwahu Afram Plains South District, Ghana - Application Of Numerical Groundwater Flow Modelling Technique(University of Ghana, 2016-07) Vakpo, K.EThe groundwater flow system in the Kwahu Afram Plains South District was simulated and calibrated under steady-state conditions. The main objective of the research was to estimate the spatial distribution of a key aquifer hydraulic parameter (the hydraulic conductivity) within an estimated range of groundwater recharge in the area and then proceed to assess the responses of the aquifer system to stresses of abstraction and reduction in recharge that may be occasioned by climate change and other stresses. A conceptual model of the domain was developed by building a hydrostratigraphy from borehole logs and defining lateral domain boundaries. The digital conceptual framework was developed using the Map module in the Groundwater Modelling System. The United States Geological Survey Modular Finite Difference code, MODFLOW-2000 in GMS 10.1 was used to simulate the numerical modelling and scenario analysis. The results of the study suggest six main lithostratigraphic units from the well log section and these units are laterite, shale, siltstone, sandstone, conglomerate and quartzite from the bottom to the top. The information gathered from the drill logs, the pseudo-sections and the geology of the area suggests the aquifers were probably encountered within the depth of (24 m – 153 m). Aquifer thicknesses vary widely in space and may be as a result of different degrees of fracturing and weathering in the area. The average aquifer thickness is about 20 m with fractured sandstone being the dominant aquifer type found in the area. Thirty (30) boreholes were carefully selected and used for this research with their depths ranging within 24m to 153m. A groundwater flow model for the area indicates general flow from the central portions of the area to the outer areas where it discharges into the Volta Lake at some places. The study finds that the hydraulic conductivity field is quite heterogeneous and has values ranging between 2.0 and 98.0 m/day. The groundwater recharge from the calibrated steady-state model was estimated to range between 0.00365 m/year and 0.1022 m/year with an average of 0.2701 m/year representing 13 % and 16 % with an average of 14.5 % of the annual precipitation of 1.10 m of annual rainfall in the area. The highest recharge appears to occur in the southern portion. The rest of the terrain has low recharge rates. From the water table budget, the source of recharge to the groundwater resource is sub-surface inflows. When the initial abstraction rates were increased up to about 50 % and beyond, dry cells were observed around some of the wells. However, if the current abstraction rate is increased by 50 % up to 200 %, the system will record drastic changes in the potential field.Item Modelling Radionuclides Transport and Dose Assessment in a Groundwater System in Somita- Taparko Goldmine in Burkina Faso(University of Ghana, 2015-07) Karim, K.; Darko, E. O.; Akoto- Bamford, S.; University of Ghana, College of Basic and Applied Sciences, Department of Nuclear Sciences and ApplicationsRadionuclides transport and dose assessment to the public in a groundwater system are described using theoretical and experimental methods. It is known that radionuclides could accumulate during mining and mineral ore processing and reach into water bodies, and thus contribute to the radiation dose received by the public who consume this water. As groundwater is inaccessible, a mathematical model with a numerical method is used to describe the relevant physical processes during radionuclide transport in the groundwater system. A computer programme has been written in MatLab to implement the numerical solution. The activity concentration and annual committed effective dose to the public from natural radionuclides (NORM) are determined for both theoretical and experimental methods. The NORM elements of interest are 238U, 232Th and 40K. The results obtained from the study revealed that the concentration of NORM in Taparko groundwater system increases with time at the point of release and becomes constant at a certain time. The concentration then decreases rapidly as far as from the release point. The average activity concentrations for theoretical method were 0.3 Bq/L, and 0.05 Bq/L for 238U and 232Th respectively at 600 m from the discharged point where the water from boreholes and wells is used by the public. For experimental analysis the mean activity concentrations were 5.57 Bq/L, 0.58Bq/L and 4.78 Bq/L for 238U, 232Th and 40K respectively. The corresponding average annual committed effective doses estimated were 0.13mSv/y, 0.28 mSv/y, for theoretical and experimental methods respectively. The theoretical and experimental results indicate insignificant exposure of the public to Natural Occurring Radioactive Materials (NORM) from the activities of the Goldmine.