GROUNDWATER QUALITY ASSESSMENT OF KARSHI AND ITS ENVIRONS, PART OF MALUMFASHI SHEET (SHEET 79 S.E) KANO STATE, NORTHWESTERN NIGERIA

This research is aimed at assessing the quality of groundwater for safe drinking in karshi and its environs, kano state. In achieving this aim, ten (10) samples were taken from both hand pump Boreholes and open wells that were selected at different settlements, taken into consideration the fact that the dwellers depend on this water for consumption and other commercial uses and that, understanding the water quality is of importance. Water from each of the selected hand pump boreholes and open wells were sampled in a sterilized 500ml plastic containers and taken to the laboratory for chemical analysis. Fifteen (15) relevant parameters on the test for water quality were taken into consideration. Analysis of physical parameters reveals that electrical conductivity is the only physical parameter with mean value of 1016.5 Mg/l that is neither within or below the permissible range of 300 – 400mg/l but rather it is higher. The mean value of chemical analysis reveals that Electrical Conductivity (Ec) and Iron (Fe) does not fall within or below the permissible ranges stipulated but rather are found to be higher, the mean concentration of Sulphate (SO4), Total Dissolved Solid (TDS), Calcium (Ca), Magnesium (Mg), Sodium (Na) are below the permissible ranges, but concentration of Magnesium (Mg) in location (RT5) is within the permissible range stipulated by (WHO, 2022), while Sodium (Na) in (RT5) is higher than the permissible range stipulated. All other physicochemical parameters such as; pH, Temp., Hardness, Nitrate (NO3-) are within the standards set by the World Health Organization (WHO, 2022) as stipulated in the WHO Standards for drinking water. Furthermore, the analysis reveals that the water are moderately suitable for drinking and no contamination. The quality of the water was understood through geological, hydrogeological and Hydrogeochemical investigations. Geological investigations reveals that the targeted area is underlained majorly by both quartzites covering about approximately 60% of the area, medium-coarse grained granite and porphyritic granites covering the remaining 40% of this study area. Hydrogeological investigation reveals that aquifer type in the area is fractured basement with water flowing perpendicular to the water level contours and from areas of high to low topography. Hydrogeochemical investigations identified NaCl and CaCl water types as the two water types in the study area and that the chemistry of water is controlled by ion exchange and simple dissolution or mixing. Durov diagram provide information on the hydrochemical facies so as to identify the water types and display some possible geochemical processes that could help in understanding the quality of groundwater and its evaluation.