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1 � <br /> 0 <br /> A S S O C I A T E S I N C <br /> No soil samples were collected from boring S112 from the surface to 40 feet bgs because the <br /> 1 boring was advanced immediately north of boring SBI completed in January 1998. No soil <br /> samples were collected from boring MW3 because this boring was advanced immediately south of <br /> boring SB 1. <br /> 1 3_2 Soil Sample Analysis <br /> ' Selected soil samples were placed on ice, and transported under chain-of-custody to Sequoia <br /> Analytical (FLAP #1210) of Redwood City, California for analysis. All soil samples were <br /> ' analyzed for TPHg, TPHd, TPHss, BTEX. In addition, two soil samples from boring SB2 were <br /> analyzed for HVOCs by EPA Method 8010. The analytical results for soil samples are <br /> summarized in Table 1. Laboratory data sheets and chain-of-custody documentation are included <br /> ' in Appendix D. <br /> 3_3 Groundwater Monitoring Well Construction <br /> 1 Soil borings MW 1, MW2, and MW3 were subsequently completed as groundwater monitoring <br /> wells to assess impacted groundwater beneath the site, and to provide measurement points for the <br /> determination of groundwater flow direction and hydraulic gradient. <br /> Each well was constructed with 2-inch PVC casing. The screened interval of each well was <br /> 1 positioned from approximately 5 feet above to 15 feet below the encountered water table to allow <br /> for seasonal water level fluctuations. The screen slot size is 0.020-inch. Well construction details <br /> are depicted on the well logs contained in Appendix C. <br /> ' 33.44 Monitoring Well Development <br /> 1 Groundwater monitoring wells MW1, MW2, and MW3 were developed on September 18, 1998. <br /> Each well was purged until the extracted water was relatively sediment free. Development/purge <br /> logs are included in Appendix E. Purgewater was temporarily stored on site in 55-gallon drums. <br /> 1 After fluid levels had been allowed to stabilize, groundwater levels were obtained from wells <br /> MW 1, MW2, and MW3. Fluid levels were taken on September 18, 1998, utilizing an electronic <br /> water probe capable of measuring with an accuracy of 11100 of a foot. Groundwater flowed to <br /> ' the east-northeast at 0.002 feet per foot. Groundwater elevation data are presented in Table 2. <br /> 1 335 Groundwater Sampling and Analysis <br /> On September 18, 1998, groundwater samples were collected from wells MW 1, MW2, and <br /> ' MW3. The samples were collected after purging a minimum of three well volumes and <br /> stabilization of electric conductivity, pH, and temperature. Field development/purge logs are <br /> presented in Appendix E. Subsequent to purging, groundwater was sampled and transferred to <br /> appropriate sample containers, using clean, disposable bailers with bottom emptying devices to <br /> w:g7295Vq)ortslsun ii.dw 4 <br /> 1 <br />