Groundwater quality studies: A Case study of the Densu Basin, Ghana

Groundwater samples from 68 communities within the Densu basin were sampled and analysed over a period of 1 year for various physico-chemical water quality parameters using appropriate certified and acceptable international procedures, in order to assess the water types as well as the suitability of groundwater within the basin for drinking and other domestic uses. The study showed that most of the physico-chemical parameters were within the World Health Organization limits recommended for drinking water. However, a few of the boreholes were slightly acidic. Someboreholes showed high level of mineralization. Borehole (GaD 6) at Pokuasi recorded the highest conductivity value of 7780.0 ìS/cm. High levels of nitrates were also recorded in certain communities within the basin. These include Aponsahene (105.8 mg/l), Damang (66.0 mg/l), Adzen Kotoku (61.5 mg/l), Afabeng (50.8 mg/l), New Mangoase (48.3mg/l), Asuoatwene (41.3 mg/l), Potrase (33.6 mg/l) and Maase (33.3 mg/l). Correlations between major ions showed expected process-based relationship between Ca2+ and Cl- (r = 0.86); Mg2+ and Cl- (r = 0.84); Na+ and SO4 2- (r =0.77); Na+ and Cl- (r = 0.75); Mg2+ and SO42- (r = 0.74); Mg2+ and Ca2+ (r = 0.71); Ca2+ and SO4 2- (r = 0.58); and K+ and SO4 2- (r = 0.51), derived mainly from the geochemical and biochemical processes within the aquifer. Two major hydrochemical water types constituting 41% of groundwater sources within the basin have been delineated. These are Ca-Mg-HCO3 water (19%) and Na –Cl or Na –Cl –HCO3- Cl water (22%) types. Fifty-nine per cent of groundwatersources are mixed waters with no particular cation predominating, and having either HCO3-or SO4 2- ions as the main anion

The Hydrochemistry of Groundwater in Some Communities in the Ayensu River Basin in the Central Region of Ghana

Hydrochemical analysis of groundwater samples in some communities in the Ayensu river basin of the central Region of Ghana was used to establish the hydrochemistry of the study area. The methodology consisted of physicochemical sampling and laboratory analysis of groundwater resources in the Basin and basic statistical analysis of the laboratory results. Generally, the groundwater is weakly acidic with a mean pH value of 6.32, had high electrical conductivity and TDS values in the range, 256.4 µS cm-1 to 2313.3 µS cm-1 and 101.7 mg/L to 1247.0 mg/L respectively. The groundwater in the area is undersaturated with respect to carbonate phases and is fresh except for one borehole at Gyangyanadze which has TDS value of 1247.0 mg/L considered as saline water.  The dominant water types in the study area are Na- Cl, Ca- Mg - Cl and Ca - Mg - SO4. The groundwater is to a large extent potable. However, approximately 13% of the groundwater samples had chloride concentrations slightly exceeding the respective WHO maximum acceptable limits for drinking water. Approximately 43%, 16% and 10% respectively of the water samples had Al3+, Fe2+ and Cd2+ concentrations above the respective WHO maximum acceptable limit for drinking water.  Silicate mineral weathering is probably the main process through which major ions enter the groundwater. Keywords:Groundwater quality  hydrochemistry  silicate weathering  Central Region  Ghana 

Shallow groundwater in the Atankwidi Catchment of the White Volta Basin: current status and future sustainability

Groundwater irrigation / Aquifers / River basins / Catchment areas / Irrigation practices / Remote sensing / Mapping / Ghana / Atankwidi Catchment / White Volta River Basin

Assessment of sources for higher Uranium concentration in ground waters of the Central Tamilnadu, India

The uranium concentration in groundwater has attained greater importance considering the health effects in mankind. Groundwater being the major source of uranium; sampling and analysis of groundwater for the major cations and anions along with uranium has been carried out in hard rock aquifers of Madurai district. The sampling has been carried out in varied aquifers like, Charnockites, Hornblende Biotite Gneiss, Granites, Quartzites, Laterites and sandstone. The cation and anions showed the following order of dominance Na+>Ca2+>Mg2+>K+ and that of anions are HCO3->Cl->SO42-> NO3->PO43-. Higher concentration of uranium was found along the granitic aquifers and it varied along the groundwater table condition. Further it was identified that the mineral weathering was the predominant source of U in groundwater. Tritium studies also reveal the fact that the younger waters are more enriched in uranium than the older groundwater with longer residence time