Evaluation of hydrochemical parameters and quality assessment of the groundwater in Gangajalghati Block, Bankura District, West Bengal, India

An investigation was carried out by collecting a total of 21 groundwater samples for two seasons in Gangajalghati Block of Bankura District, West Bengal, to decipher the hydrogeochemistry and groundwater quality for determining its suitability for agricultural and domestic purposes. Different physical–chemical parameters of groundwater samples have been determined. Sodium adsorption ratio, soluble sodium percentage, residual sodium bicarbonate, magnesium adsorption ratio, total hardness, and permeability index were calculated as derived parameters, to investigate the ionic toxicity. The groundwater is almost neutral with an average pH of 7.0 (pre-monsoon) and 6.9 (post-monsoon). The EC value varies from 562 (pre-monsoon) and 419 (post-monsoon) μS/cm. TDS range from 378 (pre-monsoon) to 360 (post-monsoon) mg/L in the study area. The Piper plot reveals the dominance of Ca2+–Na+–\({{\rm SO}_{4}^{2-}}\), mixed Ca2+–Mg2+–Na+–\({{\rm HCO}_{3}^{-}}\) types. From the plot in the U.S. Salinity diagram, the water areas are of C1–S1, C2–S1 and C3–S1 types i.e., low salinity and low sodium which is good for irrigation. The values of sodium adsorption ratio indicate that the groundwater of the area falls under the category of low sodium hazard. So, there was neither salinity nor toxicity problem of irrigation water, and hence the ground water can safely be used for long-term irrigation. Considering other derived parameters, it is found that the groundwater of the area is suitable for irrigation purposes. Comparison of our analytical results with the WHO standards of drinking water, indicates that the present waters are also good for drinking purposes.