Weathering in the subsurface environment of the Gondwana deposits intensified by the cumulative impacts of mining and agriculture practices

We present a holistic framework to evaluate groundwater contamination and its associated health risks in a mining-affected region of India with a focus on identifying key processes driving groundwater chemistry, quantifying contaminant levels, and assessing the health risks. Results revealed a complex hydrochemical regime driven by seasonal changes from pre- to post-monsoon and the intermixing of both geogenic and anthropogenic factors. A gradual change from carbonate weathering to silicate weathering from pre- to post-monsoon was observed, while anthropogenic inputs due to agricultural activities resulted in the contamination of groundwater by anions like NO₃⁻. High F⁻ levels were found to be impacted by pH levels resulting in either the desorptive release or dissolution of F⁻-bearing minerals in the mining areas. Health risk assessments showed that children were the most vulnerable. Although the imprints of agricultural inputs were more explicit on the groundwater quality than that of mining activities, the monsoon-driven dilution shifts clustering patterns of all quality parameters, indicating active recharge and mixing. The study presented an examination of enhanced weathering processes occurring in hard-rock aquifers characterized by substantial recharge rates, which are adversely affected by the cumulative influence of mining operations and agricultural practices. Future research should focus on implementing long-term monitoring programs to safeguard water resources and public health in similar settings globally.