Arsenic contamination in the groundwater of Northeastern India: Critical understandings on geotectonic controls and the need for intervention

Abstract

We investigated possible hypothesis related to arsenic (As) enrichment in the aquifer system of Northeast India, and concluded three governing deductions with explicit evidences, namely: i) the tropical environment facilitated leaching driven As release from the rocks; duly supported by reductive dissolution of clay deposition attributed to the seasonal floods in the region. ii) As-containing quaternary sediments succoured by prevailing plate tectonics in active convergent tectonic settings of the Eastern Himalayas and; iii) high precipitation, tropical climate, and biodiversity richness driven microbial mediated weathering of mineral-rich rock formations, contributing to As enrichment. We emphasized the uniqueness of the aquifer systems of Northeastern India for understanding the dynamics of prevalence and co-contaminations of geogenic contaminations like As-F-U, especially in the context of karst aquifer, and surface-groundwater interactions, implying the presence of immense opportunities of getting several insights on the fate and transport of geogenic contamination enabling the global management.