ENHANCED INSIGHTS INTO TEMPORAL AND SEASONAL FLUCTUATIONS OF ARSENIC IN GROUNDWATER: INCORPORATING HYDROCHEMICAL ANALYSIS FOR SUSTAINABLE MANAGEMENT OF POLLUTION

Arsenic contamination in groundwater presents a significant global threat to both human health and ecosystems. This element, occurring naturally, exhibits spatial and temporal dynamics influenced by geological, hydrological, and anthropogenic factors. Understanding these variations is crucial for developing effective mitigation strategies. In this study, we explore the hydrochemistry of arsenic and the contamination processes in the groundwater of the Ganga Brahmaputra river basin in India. Arsenic primarily exists in two oxidation states: arsenate (As5+) and arsenite (As3+), which can interconvert through oxidation of As3+ to As5+ and reduction of As5+ to As3+. Additionally, arsenic can exist in organic forms resulting from biomethylation. Our investigation reveals clear temporal and seasonal variability in arsenic concentrations among water samples from Ballia and Ghazipur districts in eastern Uttar Pradesh (U.P.). During the post-monsoon season, arsenic concentrations decrease in samples, reflecting a relationship with rainfall intensity. Higher rainfall leads to increased dilution, lowering arsenic concentrations in groundwater during the monsoon period. Seasonal variations in groundwater flow dynamics are influenced by water level fluctuations and subsurface redox potential, particularly during heavy rainfall. Monsoon conditions contribute to rising groundwater levels due to shallow basin characteristics and flooding, resulting in reduced groundwater flushing rates. The study also explores advanced hydrochemical analysis techniques, such as isotopic tracing, speciation studies, and high-resolution monitoring approaches.