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C A M B R I A The planned area of excavation was slightly reduced due to the presence of an active sewer lateral and a remediation piping trench running across the eastern arm of the proposed area of excavation (in the vicinity of SB-9) The depth of the excavation was determined based on the depth where groundwater was encountered during digging, which was 14 fbg Soil Sampling. Cambria collected soil samples at several locations from within the excavation Cambria consulted with SJCEHD staff and agreed upon the appropriate number and location of soil samples In general, soil samples were collected from the excavation sidewalls at approximately 5 and 10 fbg at nine locations, and from the bottom of the excavation (approximately 14 fbg) at four locations The excavator bucket was used to scoop up soil from the sample location, and the soil from the excavator bucket was packed into clean brass tubes The tube ends were then covered with Teflon tape and plastic end caps The samples were labeled, placed into a cooler with ice, entered onto a chain of custody record, and transported to a California-certified analytical laboratory Chemical Analyses Soil samples collected from the overexcavated area were analyzed for TPHg, BTEX,MTBE, and TBA by EPA Method 8260B Soil Disposal Approximately 859 tons of soil were generated during overexcavat►on activities at this site The soil was sampled and profiled for disposal The laboratory analytical data is contained in Appendix C Manley and Sons Trucking, Inc of Sacramento, California transported the soil to Allied Waste Industries' Forward Landfill in Manteca, California for disposal as it was generated during excavation activities The soil disposal confirmation is contained in Appendix D Backfill and Compaction. The finished excavation was backfilled with 1/4-inch gravel up to approximately 2 fbg Filter fabric was placed on top of the gravel and compactable fill was placed above the filter fabric The upper 2 feet of fill was compacted and compaction testing confirmed 95% compaction Compaction testing documentation is presented in Appendix E Findings• The soil chemical analytical data are summarized on Table 3 and the TPHg, benzene, MTBE, and TBA concentration data are shown on Figure 3 The certified analytical reports for the soil samples are presented in Appendix C • 0783 5