Aquifer-based arsenic safe drinking water supply in the affected areas of Middle Ganga Plain, Bihar State, India

摘要

Arsenic (As) contamination of groundwater, affecting aquifers within the alluvial and deltaic sediments in south and east Asia is considered as one of the major public health hazards of the region. An estimated 60 million people are residing within the risk zone and at least 70 million population is affected by arsenicosis (World Bank, 2005). One of the severest affected areas is Bengal Basin, covering both eastern part of West Bengal, India and major part of Bangladesh (Nickson et al., 1988). The affected aquifers are embedded in post-Pleistocene deposits and are confined within ～80 m below ground level (b.g.L). The high-As groundwater in Bengal Basin is of natural origin, as they involve the mobilization of As naturally present in aquifer material and not the discharge of pollutants by industries or related to agricultural practices. The affected areas are densely populated and depend on shallow aquifers (often lies in the depth range, reported as As-contaminated) for drinking water supply.