Aquifer vulnerability to contamination is highly variable and depends on aquifer type and depth, contaminants present, and many other variables. IST has performed aquifer vulnerability assessments at hundreds of sites at a variety of scales, from site-specific to regional analyses to state-wide studies. Results have been used by our clients to determine appropriate well head protection areas, determine appropriate exclusion zones for new service station construction, evaluate the risk to aquifers associated with existing or planned industrial construction, support passive remediation alternatives based on analysis of the soil to ground-water pathway, and to evaluate current or future aquifer risk from all sources. This is an exciting, developing field in the area of industrial risk management, and IST is at the forefront. Our technical, geological expertise, along with our modeling and GIS database capabilities, have allowed IST to accumulate immense amounts of data for analysis to look at these issues from state-wide standpoints. Results have allowed our clients to better understand aquifer sensitivity and vulnerability issues, and thereby make better decisions regarding risk and investments.