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January 2, 2007 NOA PROJECT NUMBER E06109A 1.1 Site Description The subject property is located at 16777 Howland Road, Lathrop, San Joaquin County, California (see Appendix A - Plate 1). The Assessor's Parcel Number (APN) for the Site is 198-180-05. The subject property is heavily industrialized land with open parking and storage occupying approximately fifty percent of the subject property, with buildings covering the remaining area. The elevation of the Site, according to a United States Geological Survey topographic map, is approximately 15 to 20 feet above mean sea level. The land is generally flat. 1.2 Local Geology The Site is depicted on the USGS Preliminary 7 1 /2 minute Geologic Map of the Lathrop Quadrangle as within the Quaternary Modesto Formation (USGS MAP MF - 1401). The Quaternary Modesto Formation consists of dense stipple - loose sand, probably Eolian; light stipple, loose sand and silt, chiefly fluvial; no stipple - compact silt and very fine sand (see Appendix A - Plate 2). The surface and near surface soils located at the Site are reported by the San Joaquin County Soil Survey to be composed of multiple soil types including: Manteca fine sandy loam, Merritt silty clay, Veritas fine sandy loam, Tinnin loamy coarse sand, Tokay fine sandy loam, Timor loamy sand, and Scribner clay loam (all with 0-2% slopes) (USDA, 1992). The San Joaquin County Flood Control and Water Conservation District (1998 and 1999) ground water depth and elevation maps were reviewed to determine the ground water levels near the Site. The Fall 1998 and Spring 1999 maps are the most current official maps available from the County. According to these maps, ground water lies between 10 and 20 feet below ground surface and flows at a gradient of about 4 feet per mile (0.0007 ft/ft) to the northwest in the vicinity of the Site. 2.0 ABANDONMENT OF MONITORING WELL LP-5 The abandonment of monitoring well LP-5 occurred on December 14, 2006. Prior to drilling at the Site, all necessary permits were obtained, underground utilities were located and a tailgate safety meeting was conducted. NOA, Inc abandoned the monitoring well. Harlin Knoll of the San Joaquin County Environmental Health Department (County) and James Robinson, Geologist with NOA were onsite during the 2 4