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Waste was not generated during the November 4, 2021 assessment. Groundwater was not encountered during the drilling and soil sampling activities. Photos of the site assessment activities are provided in Appendix E. Soil Analytical Results TPH-d, TPH-d and TPH-rr were detected above their respective laboratory reporting limits in soil sample SB-2-10' at concentrations of 4.88, 40.0 and 54.1 milligrams per kilogram (mg/kg) respectively. Tetrachloroethene (PCE) was detected above the laboratory reporting limit in soil samples SB-1-10' (0.00846 mg/kg), SB-2-10' (0.0203 mg/kg) and SB-2-15' (0.00451 mg/kg). 1,1,1-trichloroethane was detected above the laboratory reporting limit in soil sample SB-2-10' (0.00151 J mg/kg). Lead was detected in all soil samples collected during the November 4, 2021 assessment at concentrations ranging from 3.87 mg/kg (SB-1-15') to 8.29 mg/kg (SB-3-10'). The laboratory analytical results for soil samples collected during the November 4, 2021, assessment are tabulated in Tables 1, 2 and 3. The laboratory analytical report and chain-of-custody documentation is provided in Appendix F. Dark Oily Staining Near the Silo Per the Notice to Abate, dark oily staining was observed on the soil near the silo and parked trucks. On November 4, 2021, after site assessment drilling activities were completed, MR Drilling personnel manually excavated the stained soil at the location shown in Figure 2. The excavated soil was placed into a 55-gallon drum and a sample (Waste Profile #1) was collected and analyzed for the following: TPH-g, TPH-d, TPH-mo and TPH-rr by USEPA Method 8015; VOCs using USEPA Method 8260B; Title 22 Metals by USEPA Method 6010B; Total Solids by Method 2540 G-2011. Total xylenes were detected above their respective laboratory reporting limit in soil sample Waste Profile 4*1 at a concentration of 0.00222 J1 mg/kg. Notable concentrations of metals detected in soil sample Waste Profile #1 included arsenic (1.27 mg/kg), chromium (30.8 mg/kg) and lead (5.99 mg/kg). 1 J — Indicates the identification of the analyte at a concentration in excess of the laboratory method detection limit, but below the laboratory reporting limit. The reported value is an estimate. The laboratory analytical results for soil sample Waste Profile #1 are tabulated in Tables 1, 2 and 3. the laboratory analytical report and chain-of-custody documentation is provided in Appendix F. Photo documentation of the soil excavation is provided in Appendix E. The sample locations for sample Waste Profile #1 is provided in Figure 2. Investigation Derived Waste Soil waste generated during the soil excavation activities on November 4, 2021, was temporarily stored on-site in properly labeled, DOT-approved 55-gallon steel drum pending waste profiling for disposal or recycling. The drum containing soil waste was transported to the Potrero Hills Landfill facility in Suisun City, California. A copy of the waste disposal documentation is provided in Appendix G.