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DAMES & MOORE <br /> • A DAMES&MOORE GROUP COMPANY <br /> Fremont Investment & Loan <br /> June 15, 1998 <br /> Page 2 <br /> as a temporary well. Boreholes were backfilled with cement grout upon completion. <br /> One groundwater sample was submitted to Entech Analytical Labs, Inc. of Sunnyvale, <br /> California for laboratory analysis of volatile organic compounds (VOCs)by EPA Method <br /> 8260 and TPH Fuel Scan by EPA Method 8015M. <br /> • Advanced one boring (B-10) as above to collect one shallow(two feet bgs) and one deeper <br /> (six feet bgs) soil sample from the paint-impacted area behind Building F. The shallow <br /> sample was submitted for laboratory analysis of TPH-mineral spirits, VOCs, and selected <br /> metals. The deeper sample was submitted to the laboratory to hold pending the results of the <br /> shallow soil sample analysis. <br /> • Contacted the City of Lathrop Public Works Department and the San Joaquin County <br /> Department of Public Health regarding the potential existence and proper abandonment of <br /> the on-site water well identified on historical topographic maps and additional site <br /> observations for the potential presence of a water well. <br /> • Prepared this letter report summarizing the findings of our investigation. <br /> INVESTIGATION RESULTS <br /> On June 9, 1998, Dames & Moore performed the field investigation. Boring B-9 was advanced <br /> adjacent to Boring B-3, the boring from the previous investigation that had the highest TPH <br /> concentrations. Subsurface conditions consisted of a gray sandy silt to approximately six feet <br /> underlain by a brown silty sand with trace gravels to a depth of 12 feet. Groundwater was <br /> encountered at eight feet bgs. Boring B-10 was advanced behind Building F. Subsurface conditions <br /> consisted of a dark brownish gray,medium-grained sand to 8 feet bgs,the maximum depth explored. <br /> Groundwater was also encountered at approximately eight feet bgs. <br /> The laboratory analytical results are summarized below. The laboratory report is attached as <br /> Appendix A. Chemical analyses of groundwater sample B-9 detected 0.082 ppm TPH-diesel. No <br /> VOCs were detected. Chemical analyses of shallow soil sample B-10 did not detect the presence <br /> of TPH-mineral spirits, VOCs, or elevated concentrations of metals. Chromium, nickel, and zinc <br /> were detected at concentrations well below the California Total Threshold Limit Concentrations for <br /> hazardous wastes. <br /> Inquiries to the San Joaquin County Department of Public Health, Environmental Health Division <br /> indicate that there is a record of well destruction in 1988 for the site address; therefore, additional <br /> j research with respect to the well is not recommended. <br /> r J:JOBTREMONT\L.ATHRON RPT <br /> L Offices Worldwide <br />