Reversible adsorption and flushing of arsenic in a shallow, Holocene aquifer of Bangladesh.

ABSTRACT: The spatial heterogeneity of dissolved arsenic (As) concentrations in shallow groundwater of the Bengal Basin has been attributed to transport of As (and reactive carbon) from external sources or to the release of As from within grey sand formations. We explore the latter scenario in this detailed hydrological and geochemical study along a 300 m transect of a shallow aquifer extending from a groundwater recharge area within a sandy channel bar to its discharge into a nearby stream. Within the 10-20 m depth range, groundwater ages along the transect determined by the ³H-³He method increase from <10 yr in the recharge area to a maximum of 40 yr towards the stream. Concentrations of groundwater As within the same grey sands increase from 10 to 100 to ∼500 µg/L along this

SUBMITTER: Radloff KA 

PROVIDER: S-EPMC5404749 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature