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. f <br /> GEOMATRIX <br /> from ASB-3, ASB-8, and ASB-11 were similar to or within the range of those detected in the <br /> samples collected from ASB-7, which was the sample location selected to represent <br /> ' background conditions. The metal concentrations of these samples were less than the <br /> Preliminary Remedial Goals (PRGs)for Residential Soil and Industrial Soil (EPA,2002). <br /> l3.4.3 Grab Groundwater Data <br /> .1 <br /> TPHd was detected in the grab groundwater samples collected from ASB-1, ASB-5 through <br /> ASB-7, and ASB-11 at concentrations ranging from 110 to 2,900 µg/L(at ASB-1) (without <br /> ` silica-gel preparation procedure) (Table 9). Following the silica-gel preparation procedure, <br /> TPHd was only detected in the sample collected from ASB-1 at a concentration of 72µg/L. <br /> These results indicate that the material quantified as "TPHd" without the silica-gel preparation <br /> `. procedure was primarily polar components that may be due to intrinsic bioremediation of <br /> petroleum near this location. <br /> `l BTEX(Table 9) and PAHs (Table 10) were not detected in the grab groundwater samples <br /> l collected, with the exception of the PAH acenaphthene, which was detected at the laboratory <br /> - reporting limit of 0.2 µg/L in ASB-1. <br /> 3.4.4 Water Supply Well Data <br /> TPHg, TPHd, VOCs,PAHs, iron, and manganese were not detected in the water sample <br /> collected from the on-site supply well (Table 11). The concentrations of chloride,nitrate, <br /> sulfate, and TDS detected in this water sample were less than the drinking water standards <br /> (CCR Title 22). <br /> 1. .: 4.0 SUMMARY,CONCLUSIONS,AND RECOMMENDATIONS <br /> 1 The findings of the Bellini and Arcos property investigations conducted in August and October <br /> 1 2003, respectively, are summarized below: <br /> 1 • The site is underlain primarily by fine-grained deposits (i.e., silts) with interbedded <br /> coarse-grained deposits (i.e., sands and gravel). The depth to groundwater <br /> measured in the on-site monitoring wells has ranged from approximately 32 to <br /> 37 feet bgs. Horizontal groundwater flow direction beneath the Bellini property has <br /> j been generally to the east-northeast. <br /> 1 • Evidence of petroleum hydrocarbons in soil was observed and/or detected in borings <br /> SB-15 through SB-17, SB-19 through SB-21, ASB-1, ASB-2, and ASB-4. <br /> Petroleum-affected soil was observed within the saturated zone in these borings <br /> except for SB-17, which was observed within the unsaturated zone in the boring. <br /> i` cwaoJE=000001L0005011o1da 19 <br />