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Cambria Environmental Technology, Inc. September 25, 2001 Page 3 Follow-up investigation with the MD and GPR did not produce instrument responses typically associated with UST's. The instrument responses were those typically associated with buried utilities and minor amounts of metallic debris. A more detailed discussion of the results is provided below. A general discussion of our data interpretation procedures is provided in Appendix "B". TF The TF contour map exhibits numerous closely spaced and convoluted contour lines and closures (anomalies). These TF anomalies suggest the presence of notable amounts ferrous metal. These effects are most pronounced in the western portion of the investigation area surrounding the canopy, though some anomalies are evident in the eastern portions as well. The anomalies surrounding the canopy area can be attributed to the magnetic effects of the canopy itself, buried utility conduits, a storm drain catch basin, or possible buried debris. The contour closures in the eastern portion of the investigation area are attributed another catch basin (with concrete box) southeast of the building, the steel door, and the block walls. • MD The MD survey did not detect a buried metallic object suggestive of a UST within the investigation area. However, an apparent electric/telephone line was detected extending northward from the bank building to a utility pole outside of the investigation area. This line is depicted as the dashed red line labeled "E". A possible sanitary sewer line was detected extending northward from the building as well. GPR Our interpretation of the GPR data does not indicate the presence of a UST within the investigation area. LIMITATIONS Not all buried objects or substructures can be detected or characterized by the geophysical techniques used for this investigation. In general, there are limitations unique to each geophysical method. Paramount among these limitations is the maximum depth of investigation. Depending on the site conditions, some buried objects may escape detection because they lie beyond the a particular geophysical method's depth of investigation. Each method relies on the existence of a significant contrast in physical properties between background soils and the object or substructure of interest. Furthermore, each geophysical instrument responds differently to nearby above or below ground cultural objects such as utilities, fences, and debris. Cultural objects often cause interference, which can limit the effective