Delineation of Groundwater Quality for Drinking and Irrigation Purposes: A Case Study of Chhatna Block, Bankura District, West Bengal

The present hydro-geochemical study was confined to the Chhatna Block of Bankura district which falls between latitude 23˚20′N- 23˚30′N and longitude 86˚45′E- 86˚55′E. Twenty one groundwater samples were collected and analyzed for various physicochemical parameters like pH, electrical conductivity, total dissolved solids, Na, K, Ca, Mg, Fe, Cl, HCO3, SO4 and F were determined. Sodium Adsorption Ratio (SAR), Soluble Sodium Percentage (SSP), Residual Sodium Carbonate (RSC), Magnesium Adsorption Ratio (MAR), Total Hardness (TH), and Permeability Index (PI) were calculated as derived parameters to investigate the ionic toxicity. Based on the analytical results, groundwater in the area is generally fresh and hard to very hard. The abundance of the major ions is as follows: HCO3>Cl> SO4 and Ca>Mg>Na>K>Fe. The results also showed that bicarbonate ions (HCO3) dominated the other anions (Cl and SO4). According to Gibbs, diagrams samples fall in the rock dominance field and the chemical quality of groundwater is related to the lithology of the area. Assessment of water samples from various methods indicated that groundwater in study area is chemically suitable for drinking and agricultural uses. Fluoride is within the permissible limits for human consumption as per the WHO and Bureau of Indian standards.