Identification and management of safe groundwater supply in a high As and F^– contaminated region is a major challenge. This study provides comprehensive hydrogeochemical investigation results for a complex hydro-stratigraphy controlled soil aquifer, which is bound between the Shillong plateau and the Himalayan ranges in the North-Eastern region of India. In this study, distinct contaminated regions of As and F^– were identified in the post-monsoon (n = 94) and winter (n = 50) seasons groundwater samples. The maximum dissolved concentration of As was measured to be 71 µg L^–1 in post-monsoon and 211 µg L^–1 in winter season groundwater samples. Maximum F^– concentration was measured as 7 mg L^–1 in post-monsoon and 6 mg L^–1 in winter season groundwater samples. Identified minerals saturation, weathering and dissolution condition results were well corroborated with the hydrogeochemistry, Bivariate plot, Gibbs and Pourbaix diagrams results. Children of age below 18 years old, in total 20% (i.e. 6,511) and 25% (i.e. 3,627) of the residents were found to be more susceptible to arsenic ingestion effect. The results of health risk assessment showed that the population of age below 18 years old are prone to carcinogenic diseases as well as a symptoms of non-carcinogenic health risk due to daily consumption of As contaminated groundwater. The male population was found relatively more prone to As cancer risk than the female population. Overall, this study provides a critical result about the cause of high As and F^– concentration in groundwater and their health risk assessment. It seek to address a prime concern for the usage of groundwater source for drinking water in the Brahmaputra flood plain.

鉴定及在高砷，氟地下水安全供应管理^-污染的地区是一个重大的挑战。这项研究为复杂的水文地层控制的土壤含水层提供了全面的水文地球化学调查结果，该含水层位于印度东北部的西隆高原和喜马拉雅山脉之间。在这项研究中，在季风后 ( n  = 94) 和冬季 ( n  = 50) 季节地下水样本中确定了不同的 As 和 F ^–污染区域。测得的最大溶解砷浓度在季风后为 71 µg L ^–1，在冬季地下水样品中为211 µg L ^–1。最大 F ^–季风后的浓度为 7 mg L ^–1和 6 mg L ^–1在冬季地下水样本。识别的矿物饱和度、风化和溶解条件结果与水文地球化学、双变量图、吉布斯图和普贝图结果得到了很好的证实。18 岁以下的儿童中，共有 20% (即 6,511) 和 25% (即 3,627) 的居民更容易受到砷摄入效应的影响。健康风险评估结果表明，18岁以下人群由于日常饮用As污染的地下水，易患致癌疾病，并出现非致癌健康风险症状。发现男性人群比女性人群相对更容易患 As 癌症风险。总的来说，这项研究提供了关于高 As 和 F 的原因的关键结果^-地下水浓度及其健康风险评估。它寻求解决在雅鲁藏布江洪泛区使用地下水源作为饮用水的主要问题。