Systematic Study of Arsenic Contamination in Irrigation Well and its Surrounding Drinking Water Well in Chakdaha Block of West Bengal, India using Different Parameters

All over the world ground water is used for drinking, domestic (cooking, bathing) and agricultural purposes.In the last few decades in several countries, it has been found that ground water is contaminated with geogenic arsenic (As).Arsenic contamination is mostly reported in south-east Asian countries namely India (mainly West Bengal) and Bangladesh.It has been found that arsenic contamination is mostly occurred in rural part of Bengal Delta Plan (BDP) where summer irrigation has been regularly used for Boro-cultivation.Arsenic mobilisation from ground to surface water happens due to the pumping of ground water.The present study highlights the role of pumping on Arsenic mobilization.Three different villages [Site 1 (Sashipur), Site 2 (Mathurgachi) and site 3 (Banamalipara)] have been selected where pumping is going on by irrigation well and a few drinking wells are surrounded with pumping well.The study indicates that two different situations have been observed in between three different study areas, the situation 1: site 2 and site 3 where As concentration in ground water in large remain unchanged during pumping period (starting and ending).However, in ground water quality parameters such as bicarbonate, conductivity, pH, hardness and iron has been changed along with increase in as concentration.These further suggest that there will be intense sediment water interaction in the site1 that ultimately reflected in change of the ground water quality.Apart from this it has been found that a pond is also located very near about ~5-10m to the irrigation well site1.There is good possibility that the pond can supply fresh organic matter to the aquifer due to pumping and thereby increasing sediment water interaction which ultimately increases As concentration in ground water.