Footprint Reduction Process: Using Remote Sensing and GIS Technologies to Identify Non-Contaminated Land Parcels on the Oak Ridge Reservation National Priorities List Site

In 1989, the Agency for Toxic Substances and Disease Registry evaluated the entire 35,000-acre U. S: Department of Energy (DOE) Oak Ridge Reservation (ORR, located in Oak Ridge, TN) and placed it on the National Priorities List (NPL), making the ORR subject to Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) regulations. Although much of the ORR has not been impacted by previous federal activities, without investigation it is difficult to discern which parcels of land are free of surface contamination. In 1996, the DOE Oak Ridge Environmental Management Program (EM) funded the Footprint Reduction Project to: 1) develop a process to study the large areas of the ORR that are believed to be free of surface contamination and 2) initiate the delisting of the "clean" areas from the NPL. Although this project's goals do not include the transfer of federal property to non-federal entities, the process development team aimed to provide a final product with multiple uses. Therefore, the process was developed to meet the requirements of NPL delisting and the transfer of non- contaminated federal lands to future land users. Section 120 (h) of the CERCLA law identifies the requirements for the transfer of federal property that is currently part of an NPL site. Reviews of historical information (including aerial photography), field inspections, and the recorded chain of title documents for the property are required for the delisting of property prior to transfer from the federal government. Despite the widespread availability of remote sensing and other digital geographic data and geographic information systems (GIS) for the analysis of such data, historical aerial photography is the only geographic data source required for review under the CERCLA 120 (h) process. However, since the ORR Environmental Management Program had an established Remote Sensing Program, the Footprint Reduction Project included the development and application of a methodology for integrating other existing geographic data sources into the CERCLA 120 (h) review of each study area. The process that was developed and initiated uses historical information, multiple remote sensing technologies, and GIS to identify areas of potential contamination within each study area. Non-intrusive field investigations are conducted to determine the causes of each area of potential contamination. Once the Footprint Reduction Process is complete for each study area, the clean areas within the study area are submitted to regulating agencies for approval and removal from the NPL