Hydrochemistry and Arsenic Contamination of Shallow Aquifers in Bidyananda and Nazimkhan Unions, Rajarhat Upazilla, Kurigram, Bangladesh

In this study, the spatial distribution and hydrochemistry of arsenic (As) in shallow alluvial aquifers of Bidyananda and Nazimkhan Union of Rajarhat opazilla, Kurigram district of Bangladesh have been evaluated. Nineteen groundwater samples (depth: 10 to 50 m) were collected from the studied area for physical and chemical analysis. Based on analytical data of chemical analysis, a Piper trilinear diagram have been prepared which revealed that the groundwater of the studied area is CaHCO3 type, where Ca is the dominant metal. Physical data and permeability index values indicate good quality of the groundwater for drinking and irrigation. The concentrations of Fe, Mn and As in almost all samples exceed the WHO and Bangladesh national standard indicating significant pollutions. Groundwater As concentrations in the aquifer (10–50 m of depth) ranged from