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I. Kleinfelder December 10, 2003 Page 4 of a UST, it is also plausible that the wet conditions, including the standing water and presumably wet, electrically conductive sub-asphalt soils may have masked the metallic response of a buried object. In some cases, extreme corrosion of metal USTs can also result in a diminished metallic response from a UST in locally conductive soil areas. MD Anomalies and Utilities We identified one MD anomaly outside of the reinforced concrete area, several feet east of Anomaly B. This anomaly is small, measuring approximately 1-by-2 feet, and is approximately 3-to-5 feet west of the concrete apron. It may or may not be related to Anomaly B. During the course of this UST survey, we detected 8 undifferentiated utilities of an unknown type and one storm drain line exiting the catch basin. The respective locations are also shown on Plate 1. We identified most of the undifferentiated lines with GPR only. Due to their abrupt terminations, some of these may actually represent linear pieces of debris. As it was not the primary objective of the survey, not all utilities may have been detected and/or marked out at the site. For example, sanitary sewer lines are not typically detectable with the techniques used for this survey. SUMMARY We interpret four areas (Anomalies A-D) where potential USTs may be located. This is based on the use of the GPR method without corroboration from the MD method. Although the results did not conclusively determine the sources of these anomalies are USTs, there are indications of potentially significant localized objects in these four locations. To definitively determine whether or not USTs are present in any of these locations, we recommend investigation by intrusive measures, such as pot-holing at the centers of the anomalies, expanding each search radially a few feet (if necessary) to uncover the anomaly source. Additional anomalies were identified throughout the survey area, but the sizes and GPR characteristics of these features are not consistent with that expected from USTs. Finally, through the course of the survey, we located assorted utility lines including one storm drain line exiting a catch basin. However, as it was not the primary objective of the survey, not all utilities may have been detected and/or marked out at the site. I.