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��U vE9 X820 3.0 FINDINGS 3.1 Site Geology& Field Observations Based on Bureau Veritas' observations at the subject property, soils were generally brown to dark brown with orange and black mottling,and consisted of clay,silty clay,clayey silt,sandy silt,and silt to the maximum soil boring depth of 36 feet bgs. Thin fine-grained sand beds ranging from a few inches up to one foot thick were observed at various depths below 20 feet bgs in BV-1 through BV-5. A silty sand bed between 16 and 21.5 feet was observed only in BV-5. No native sands were noted in BV-6, which was only advanced to 12 feet bgs. With the exception of BV-6, encountered groundwater appeared to readily enter each borehole and stabilized within a couple of minutes with approximate depths to water in BV-1 through BV-4 ranging between 29.13 and 30.83 feet bgs. The depth to water in BV-5 was recorded at 26.5 feet bgs, as the top of the well was at a lower elevation. Groundwater was not encountered in BV-6. Bureau Veritas did not observe evidence of petroleum hydrocarbons or VOC contamination in soils (e.g., discoloration, odors) in the borings advanced during this subsurface investigation with the exception of BV-2, BV-3, and BV-4 below 29.5 feet bgs, the approximate depth of the groundwater table where some petroleum hydrocarbon odors and slight mottled black soil staining was observed. No elevated PID readings were recorded, except for BV-2 at a depth of 29.5 feet bgs where a PID reading of 159.8 ppm was recorded. This corresponded to the approximate depth of the groundwater table; however, there was little if any petroleum hydrocarbon staining of the soil at this depth. Observable soil staining was noted in BV-3 at about 31 feet bgs and in BV-4 mottled black staining was observed between 28 and 35 feet bgs. Based on field screening findings, soil samples BV-2 at 27.5 feet and BV-4 at 27.5 feet were submitted for laboratory analyses. Soil boring logs presented in Appendix C provide more details. 3.2 Soil Analytical Results No TPH or VOC concentrations were reported above the laboratory reporting limits in the two soil samples, BV-2 and BV-4, submitted for analysis as summarized in Table 1. A copy of the soil analytical laboratory report is presented in Appendix E. 2.4 Grab-Groundwater Analytical Results A summary of the analytical results for TPH and VOCs for grab-groundwater samples is provided in Table 2. The VOC analytical results for grab-groundwater samples were compared to California EPA Department of Health Services(DHS) Primary Maximum Contaminant Levels(MCLs). No MCLs have been established for TPH concentrations. A copy of the grab-groundwater analytical laboratory report is presented in Appendix F. TPH compounds were detected in four of the five analyzed grab-groundwater samples. TPH-g was reported in BV-3 and BV-4 at 160 and 250 ug/L, respectively. TPH-d (quantified as diesel)and TPH-mo(quantified as motor oil)were reported in BV-1 through BV-4. TPH-d concentrations ranged from 140 to 3,000 ug/L, and TPH-mo from 870 to 12,000 ug/L, with the highest concentrations noted at BV-2. The laboratory noted that TPH-d at grab-groundwater sample BV-2 resembled a Stoddard solvent pattern; the chromatogram at grab- groundwater sample BV-3 resembled a kerosene pattern. As presented in Table 2, concentrations of various VOCs were reported in the analyzed grab- groundwater samples, which included acetone, tert-butyl alcohol (TBA), 1,2-DCA, cis-1,2- dichloroethene(DCE), tetrachloroethene(PCE), and trichloroethene(TCE). PCE concentrations ranged from 1.5 to 610 ug/L; TCE concentrations ranged from 2.8 to 36 ug/L. In addition, PCE degradation compounds of 1,2-DCA and cis-1,2-DCE were also detected in the grab-groundwater samples. The grab-groundwater samples exceed one or more primary MCLs as noted in Table 2. 7 Project Number 99008-008321.03