HYDROGEOLOGICAL STUDIES AND GROUNDWATER CHEMISTRY OF SELECTED AREAS OF DISTRICT HARIPUR, KHYBER PUKHTUNKHAWA, PAKISTAN

Abstract

The present study has been carried out to evaluate the subsurface lithology based on three-dimensional model. Lithological logs of the study area clearly suggest that conglomerate (boulder and gravel) materials is dominant in the area and all the aquifer material was conglomerate. Semi confined to confined aquifer present in the study area. Clay act as confining materials. The hydrochemistry of groundwater in the Haripur district has been analyzed to assess its suitability for drinking purposes. An effort has been made to delineate the sources of these groundwater chemical constituents by relating them with the hydrogeological system, land use and drainage areas. A total of 42 samples of groundwater were collected to analyze the physicochemical, major and minor constituents in the groundwater of the Haripur District. The analysis of physicochemical results was compared with Pakistan Standard Quality Control Authority (PSQCA) and World Health Organization (WHO) standards for suitability. By using Arc GIS spatial distribution map of major ions (cations and anions) have been prepared including Calcium (Ca2+),Sodium (Na+), Magnesium (Mg2+), Potassium (K+), Chloride (Cl-), Bicarbonate (HCO3) and Sulphate (SO4-2).Most of the samples lie within the permissible range of drinking water quality. However, in some samples Cl- and Na+ concentration exceed the permissible limits that could be dangerous for health. By using Piper Trilinear Diagram (1944) major hydrochemical facies were identified. All the field data showed three different groups of water. Dominant groups are Ca-HCO3 (52%) Na-Cl-SO4 (21%) and mixed type Ca-Mg-HCO3 Ca-Na-HCO3(26%).Ca-HCO3type water is low mineralized, freshwater. Based on Sodium Adsorption Ratio, 04 samples are unsuitable for irrigation. Wilcox’s classification shows that 90% of samples fall in the C2S1 category which is permissible for irrigation purposes. The study furnished the fact that the hydrochemical facies and the constituents are majorly controlled by hydrogeology, water depth, land use and drainage.