A Comprehensive Approach to Groundwater Vulnerability Mapping Using DRASTIC and Sensitivity Analysis in Jeypore, Koraput, India

ABSTRACT Groundwater vulnerability assessment is considered essential for the sustainable management and protection of subsurface water resources. In the present study, the DRASTIC model was applied to evaluate the vulnerability of aquifers in the Jeypore Block of Koraput District, Odisha, India. To enhance the reliability of the vulnerability map, sensitivity analysis—comprising both single parameter sensitivity analysis (SPSA) and map removal sensitivity analysis (MRSA)—was integrated to assess the influence and effectiveness of individual parameters and their assigned weights. The results revealed that the southern part of the study area is more prone to groundwater contamination than the northern region. Sensitivity analysis identified net recharge, depth to the water table, and the impact of the vadose zone as the most influential parameters. Additionally, model performance was validated using receiver operating characteristic (ROC)–area under the curve (AUC) analysis, which confirmed the predictive capability of the DRASTIC model in the local hydrogeological setting. The use of open‐access geospatial datasets, combined with GIS‐based techniques, ensured the replicability and cost‐effectiveness of the approach. The findings are expected to support policymakers and local authorities in formulating informed strategies for groundwater conservation, land‐use planning, and pollution control.