Nonlinear AC Response in Bilayer Lipid Membrane

The groundwater arsenic contamination in Bangladesh is a phenomenon of surface ero- sion, transportation and deposition in the form of Delta and ∼lood Plain. While dealing with such geomorphological units like Tableland, Flood Plain, Delta and Hill Tract in Bangladesh, we have found the possibility of having huge arsenic contaminattion free groundwater reservoir in selected areas in Bangladesh. The results presented are the outcome of our last 5 years, field survey analysing for arsenic of water of twentyfive thousand eight hundred ninetyseven hand tubewells in sixtyfour districts of Bangladesh comprising four existing geomorphological regions (a) Deltaic region (including coastal region), (b) Flood Plain, (c) Tableland and (d) Hill Tract. In this report, we will highlight (1) the area in Bangladesh where groundwater is not arsenic contaminated and the' possibility to use shallow hand tubewells as potential groundwater resource for drinking purpose and (2) arsenic contaminations scenario of deep tubewells (above 100 meters) all over Bangladesh and suitable depth in arsenic contaminated area to get safe water.