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Each of the 12 soil samples collected was analyzed for percent moisture, <br /> pH and alkalinity. As a result of limited sample volume, the alkalinity <br /> analysis was omitted from the chain-of-custody form. The expected <br /> background level for pH should be between 6.5 and 8.5. Actual soil pH <br /> results ranged from 5.2 to 10.8. Seven of the 12 soil samples had a soil pH <br /> within the suggested level. One soil sample was below the average pH <br /> 1 range and four soil samples were above the expected background level. <br /> 4.2 GROUNDWATER CHARACTERIZATION <br /> 4.2.1 Depth to Groundwater and Flow Direction <br /> Depth to groundwater was measured on 12 January 2005 in temporary <br /> wells SB-4 through SB-7. Groundwater elevations ranged from-0.47 feet <br /> below mean sea level(msl) to 0.79 feet above msl. The direction of <br /> groundwater flow determined during this investigation is generally to the <br /> rj south (Figure 2) and expected to be influenced by seasonal variability and <br />�J rainfall. The groundwater gradient is estimated to be between 0.0115 and <br /> 0.0156 feet per foot. <br /> 4.2.2 Reconnaissance Groundwater Analytical Data <br /> Recorunaissance groundwater samples were collected from four temporary <br /> wells,screened from 7 to 12 feet bgs that were installed as part of the site <br /> investigation. Each of the four groundwater samples were collected and <br /> analyzed for one or more of the constituents identified in Section 3.2.3. <br /> Analytical results for reconnaissance groundwater samples are presented <br /> in Table 4. The following sections discuss the results of the <br /> reconnaissance groundwater samples at the site. <br />,11 4.2.2.1 Total Metals <br /> J <br /> Of the 13 metals included for analysis,10 metals (arsenic,beryllium, <br /> cadmium, chromium,copper, nickel,lead, selenium,zinc, and mercury) <br /> were detected in SB-5,SB-6,and/or SB-7. Temporary well SB-4 did not <br /> yield enough water to collect a total metal sample. Total metals <br /> 1� concentrations in these three temporary wells were detected above the <br /> Region IX tap water PRG and/or their respective PMCL/ SMCL in nine of <br /> the 10 metals analyzed. The following table presents the detected total <br /> metal concentrations above the Region IX Tap Water PRG and/or <br /> ERM 10 LMM/W2A301-3/3/2005 <br /> IJ <br /> IJ <br />