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1 <br /> OEOMATRIX <br /> B3-5 using a Vibra-Push XD-1 track-mounted rig (Figure 2) Two boreholes, approximately <br />' 6 inches apart, were advanced using the direct-push method The first borehole was used for <br /> collecting continuous soil core samples for lithologic logging and field screening The second <br />' borehole was used for collecting a discrete-depth grab groundwater sample for delineating the <br /> vertical extent of affected groundwater at the site <br />' Continuous Soil Coring <br /> The first borehole of B3-14 was advanced to approximately 49 feet bgs using the dual-wall <br />' (double core-barrel) method The outer barrel for advancing the soil boring was 2 inches in <br /> diameter and the inner barrel for soil core sampling was 175 inches in diameter Soil samples <br />' were collected for field screening and lithologic logging by Geomatnx field staff under the <br /> direction of a California Registered Geologist Field screening included measurement of total <br />' volatile organic compounds (VOCs) in the headspace of the soil samples using a <br /> photmomzation detector (PID) and examination of the soil samples for discoloration/staining <br /> 1 and/or petroleum odor The soil samples were logged using visual/manual procedures in <br /> accordance with the Unified Soil Classification System described in the American Society for <br /> Testing Materials Standard D 2488-90 Since the vertical extent of petroleum hydrocarbons in <br /> soil has been adequately delineated based on the existing soil data collected from B3-5 and <br /> other borings (descnbed in Section 4 3), laboratory analyses were not requested for the soil <br />' samples collected from boring B3-14 <br />' Grab Groundwater Sampling <br /> A discrete-depth grab groundwater sample was not collected at 20 feet bgs because there was <br /> not sufficient groundwater for sampling at this depth in the first borehole of B3-14 Field <br />' screening results of the soil samples collected from the first borehole indicate that the vertical <br /> extent of soil affected by petroleum hydrocarbons was between about 10 and 36 feet bgs <br />' (described in further detail in Section 4 3) Based on these results and the ltthology observed <br /> to the first borehole, the 2-inch diameter core-barrel was advanced in the second borehole of <br />' B3-14 to about 38 feet bgs with a ttp at the bottom of the barrel to case off the affected soil <br /> Then a HydroPunch groundwater sampler was advanced through the 2-inch diameter barrel to <br />' about 44 feet bgs The screened interval of the groundwater sampler was exposed from about <br /> 40 to 44 feet bgs for groundwater sampling A grab groundwater sample was subsequently <br />' collected from inside the sampler using a bailer <br /> 11PROJECMOOM6437 000/6437 08 doc 6 <br /> 1 <br />