GIS has become an important tool in the risk assessment analyses that provide support to EPA policy making. This paper will focus on how GIS is used to provide different spatial data sources to one such multimedia, multipathway human health risk assessment. GIS is used to analyze multiple data sources, including environmental, population, agricultural, and elevation, and provide a site-specific look at land-based waste management units (WMUs) across the United States. Data gathered from a specified radius around a sample of sites is passed to risk models that will estimate human population health risks and ultimately help guide EPA policy.