ABSTRACT
Arsenic (As) enrichment in aquifers originate generally from naturally occurring arsenic, in clay and organic-rich sediments containing As-rich minerals with Fe/Mn oxides (Xie et al. 2008). Geochemical and mineralogical features of the aquifer sediments were investigated in Barasat, India, a part of the Gangetic Basin, in order to gain a better understanding of As binding mechanisms and the mobilization processes responsible for As enrichment. High As has been reported in shallow groundwater (<70 m depth) in this area which is consistent with other data indicating presence of elevated levels of arsenic in groundwater as well as in subsurface sediments (McArthur et al. 2004; Kar et al. 2010). The aquifer sediments are primarily alluvial deposition of Holocene and Recent sediments deposited by the Ganges River. Arsenic contents in sub-surface sediments from high As water zones are considerably high. The aim of this study was to determine the probable release mechanism by using sequential extraction technique along with XRD and EDS studies to reveal the binding mechanism of As along with other geochemistry and mineralogy of the sediments.
