WESTON has been retained by the United States Air Force Occupational and Environmental Health Laboratory USAFOEHL to provide general engineering, hydrogeological, and analytical services. USAFOEHL assisted in analysis and remediation of a JP-4 spill that had occurred at the base. McGAFB has identified the source of the spilled fuel as the lines associated with the now inactive railroad off-loading facility see Figure ES-1. The leak was effectively stopped by permanently disconnecting these lines from the fuel system. Therefore, the following Technical Scope of Work deals only with the second and third aspects of a fuel spill evaluation. USAFOEHL issued Task Order 3 of this contract dated 20 July 1984 authorizing WESTON to perform an investigation at the base Bulk Fuel Storage Area. As the primary parameters for evaluation of fuel migration and subsequent groundwater contamination, WESTON used the following analytes Benzene, Toluene, and Xylenes BTX. Oil and grease OG.