Biased sampling methods often employed during site characterization, coupled with the assumption that contaminants are lognormally distributed, may contribute to overly conservative estimates of the exposure point concentration (EPC) and associated risk, and may result in inefficient allocation of limited cleanup resources. With GeoSEM, risk assessors and remedial project managers can exploit the geospatial information contained in environmental data to calculate more accurate estimates of exposures to potential human and ecological receptors. Provides a unique statistics and mapping tool explicity designed for risk assessment and risk-based decision making. GeoSEM is a GIS-based application that is designed for the Microsoft® Windows® environments.