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lw ec0100 and ellAmIment,inc. 4. Analytical Data 4.2.1 Analytical Results for TPH in Soil TPH-g was not detected in any surface or subsurface soil samples at concentrations above the laboratory reporting limit during the January 2011 sampling event. TPH-d was detected in nine surface and subsurface soil samples throughout the site at concentrations below the action level, except for one location, EC2-07. At location EC2-07, TPH-d was detected in the surface sample at a concentration of 110 mg/kg, which is above the action level of 100 mg/kg. TPH-mo was detected 13 surface and subsurface soil samples throughout the site but all at concentrations below the action level. TPH data is presented in Table 1 in Appendix C. The complete laboratory analysis data reports for all samples are contained in Appendix D. 4.2.2 Analytical Results for RCRA Metals in Soil RCRA metals were present in soil samples throughout the site,but were typically at concentrations below their site-specific action levels. Arsenic was detected in surface and subsurface soils from all 55 samples collected at the 11 boring locations at concentrations above the site-specific action level of 0.24 mg/kg. These concentrations of arsenic ranged from 0.62 to 4.4 mg/kg. No other metals were detected in the soil at concentrations exceeding their respective action levels. The highest concentration of arsenic was detected at sample location EC2-08 at 0.5 feet bgs at a concentration of 4.4 mg/kg. As reported by Bradford, et al, in the Background Concentrations of Trace and Major Elements in California Soils report in March 1996 (Bradford, et al 1996), arsenic is a naturally occurring element in the earth and in the San Joaquin Valley; it had been assessed in natural background concentrations ranging between 0.8 and 20 ppm(Bradford, et al, 1996). It is likely that the concentrations of arsenic found at the site are the result of natural mineral deposits and not contamination from human activities. Metals data is presented in Table 2 in Appendix C. The complete laboratory analysis data reports for all samples are contained in Appendix D. Figure 4 (Appendix A) lists contaminant concentrations for samples where a screening level was exceeded. 4.2.3 Analytical Results for VOCs in Subsurface Soil Volatile organic COPCs were generally not detected in soil samples above their respective laboratory reporting limits. Ethylbenzene was detected in soil sample EC2-S-09-10 at an estimated concentration of 0.00064 mg/kg, which is below the action level established for this assessment of 3.3 mg/kg. Xylene was detected in two soil samples collected at boring location EC2-09 at depths of 5 ft bgs (0.00011 mg/kg) and 10 ft bgs (0.00033 mg/kg), which are below the action level established for this assessment of 2.3 mg/kg. Methylene chloride was detected in two soil samples collected at boring location EC2-01 at the surface (0.00029 mg/kg) and at 2.5 ft bgs (0.0003 mg/kg), which are below the action level established for this assessment of 0.077 mg/kg. 1,2,3-Trichlorobenzene was detected in soil sample EC2-S-09-10 at an estimated concentration of 0.00064 mg/kg and at EC@-S-112-15 at an estimated concentration of 0.00064 mg/kg. There is no listed regulatory level for 1,2,3-Trichlorobenzene. 1,2,4-Trichlorobenzene was detected in soil sample EC2-S-112-15 at an estimated concentration of 0.0004 mg/kg, which is below the action level established for this assessment of 1.5 mg/kg. Chloroform was detected in four soil samples throughout the site at concentrations ranging from 0.00037 mg/kg to 0.00 13 mg/kg, which are below the action level established for this assessment of 0.68 mg/kg. 4-2