DRASTIC is a standardized parametric index model used to assess groundwater vulnerability to contamination by evaluating seven hydrogeological factors: Depth to water, net Recharge, Aquifer media, Soil media, Topography, Impact of the vadose zone, and hydraulic Conductivity. Within GIS environments, DRASTIC analysis leverages spatial data integration to map and quantify pollution risk across geographic extents with precision and scalability previously unachievable through manual methods.

GIS technology enables analysts to compile, reclassify, and weight multiple geospatial data layers — including soil surveys, digital elevation models, lithological maps, and hydrological datasets — then apply the DRASTIC rating formula through raster-based geoprocessing workflows. Each parameter is assigned a weighted score, and spatial analysis tools aggregate these layers into composite vulnerability maps that visually communicate contamination risk gradients across a study area.

The practical benefits for geospatial analysts and environmental planners are substantial. GIS-driven DRASTIC assessments support land use planning, wellhead protection programs, regulatory compliance, and sustainable resource management. By automating complex multi-criteria spatial analysis, professionals can rapidly update models as new geospatial data becomes available, improving decision-making accuracy for groundwater protection initiatives at local, regional, and national scales.