Mitigation and Remedy of Groundwater Arsenic Menace in India

Arsenic Menace in India- An Appraisal2.3.3.2 BiharIn 2002, groundwater arsenic contamination first surfaced in two villages, Barisban andSemaria Ojhapatti in the Bhojpur district of Bihar in the Middle Ganga Plain. The area is locatedin the flood-prone belt of Sone-Ganga inter-fluve region. Investigations by Central Ground WaterBoard and Public Health Engineering Department, Bihar indicated contamination as high as .178µg/L in the surrounding villages, affecting the hand pumps, which are generally at 20-40 m belowground surface. With ongoing study, more and more contaminated districts have surfaced. It wasreported (CGWB, 2008) that by the year 2008, out of 38 districts, 15 districts covering 57 blocksare exposed to groundwater arsenic contamination above 50 µg/L. These districts are: i) Buxarii) Bhojpur, iii) Patna, iv) Lakhisarai v) Saran, vi) Vaishali vii) Begusarai, Samastipur, ix) Munger,x) Khagaria, xi) Bhagalpur xii) Darbhanga, xiii) Purnea xiv) Katihar xv) Kishanganj(Figure-2.7). These districts are mostly distributed along the course of the river Ganga in Biharexcept three; (i) Darbhanga, (ii) Purnea and (iii) Kishanganj, which are in isolated and scatteredplaces showing no distinct routes of connection to one-another (Figure 2.7). It was also predictedthat the districts lying in the area where Ganga and other tributaries, originating from theHimalaya, shifted in course of time, would be arsenic contaminated (Figure 2.8). The blocksidentified as arsenic affected in each district are given in Table-2.5 (CGWB, 2008). The geologicalformations in the affected areas are of Quaternary deposits of multi-aquifer systemsmixed with medium to fine sands having occasional coarse grained followed by medium sand,pebble and gravel, etc. Figure 2.9 shows some arsenic patients from arsenic affected districtsof Bihar.Figure 2.7 : Location of 15 Arsenic affected districts in Bihar.22NIH & CGWB