U. S. military training installations often experience significant environmental damage from soil erosion.  A major portion of these erosion concerns are caused by the facility roads and trails that are often created by repeated use by military vehicles during training operations.  If they are located on slopes or in areas of concentrated runoff, soil loss can greatly increase. A geographic information system (GIS) software package and a modified version of the Universal Soil Loss Equation (USLE) were used to estimate erosion potential at Camp Atterbury located in south central Indiana.  The results for erosion potential with and without vegetative cover were compared so that potential erosion reductions for closure of trails/roads and their revegetation or improvement could be obtained.  Each erosion estimate was overlain with the roads and trails map to obtain a map depicting the potential level of erosion for the roads and trails. The estimated erosion levels on the roads and trails were then validated with on-site inspections of erosion conditions at Camp Atterbury. A significant correlation exists between predicted and observed erosion potential at Camp Atterbury. The statistical significance for the modified USLE process allows the site wide erosion potential to be used with confidence within a Decision Support System (DSS) or for other uses. A web-based DSS has been created that utilizes the validated GIS and erosion estimation process.  It provides the user a capability to digitize a trail/road segment anywhere on Camp Atterbury, estimate the total erosion in each of 3 potential erosion categories (low, moderate, and high) with and without cover, and compare these erosion estimates to provide total estimated erosion reduction for road/trail closure and revegetation.  The DSS can help a land manager by identifying roads and trails that should be closed or improved.