Groundwater Arsenic in the Bengal Delta Plain: Geochemical and Geomorphological Perspectives

The presence of arsenic (As) in groundwater is a wide- spread problem in south-east Asia, especially West Bengal (India) and Bangladesh. Water quality and chemistry of the groundwater have been investigated by a systematic screening operation of tube wells in a locality in West Bengal (India). Groundwater is predominantly of Ca-HCO3-type and is occasionally enriched with Na and Cl- in shallow wells (15-20 m) which may be an indicator of local pollution source. The groundwater As distribution and their relationship with land-use characteristics suggest that As release is also influenced by local land use conditions (e.g., sanitation, surface water bodies and agricultural practices). The interconnectivity of these land use conditions with the aquifer underneath often facilitates As release creating heterogeneity in their distribution. (C) 2017 The Authors. Published by Elsevier B.V.