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1 v <br /> A S S O C I A T E S I N C <br /> On October 4, 2001, soil boring CPT 1 was advanced by Fisch Environmental The boring was <br /> advanced near former borings SB 1 and SB2, the area of highest petroleum hydrocarbon <br /> concentrations, to evaluate the deeper subsurface conditions A cone mounted with sensors at the <br /> tip was advanced into the soil using direct push rods The sensors tested the response of the soil <br /> to the force of the penetrating cone and this allowed the subsurface stratigraphy to be <br /> ' characterized The CPT boring was advanced to approximately 16 feet bgs when probe refusal <br /> occurred Drilling resumed without logging to prevent significant damage to the CPT equipment <br /> The boring was further advanced to approximately 45 feet bgs, and a groundwater sample was <br /> 1 collected using a Geoprobe® Screen Point 15 Groundwater Sampler threaded onto the leading <br /> end of the Geoprobe After the sample has been collected, the baring was grouted to the surface <br /> The CPT boring log is contained in Appendix A <br /> 2_2 Soil Sample Analysis <br /> Selected soil samples were placed on ice, and transported under chain-of-custody to Argon <br /> Laboratories (ELAP #2359) of Ceres, California for analysis All soil samples were analyzed for <br /> total petroleum hydrocarbons as gasoline (TPHg) and benzene, toluene, ethylbenzene, and xylenes <br /> ' (BTEX) utilizing EPA 8015 and 8020 methodologies, and oxygenate fuel additives utilizing EPA <br /> 8260 methodology The analytical results for soil samples are summarized in Table 1 Laboratory <br /> data sheets and chain-of-custody documentation are Included in Appendix B <br /> 2.3 Groundwater Sam lin and Analysis <br /> ' On October 4 and 5, 2001, soil borings SB7 through SB12 were advanced to depths ranging <br /> between 25 and 30 feet below ground surface (bgs) depending on the depth at which groundwater <br /> ' was encountered in each boring One groundwater sample was collected from each boring at the <br /> depth groundwater was first encountered, approximately 25 to 30 feet bgs A Geoprobe® Screen <br /> 1 Point 15 Groundwater Sampler was threaded onto the leading end of the Geoprobe after <br /> r ' groundwater had been encountered When the sampler was advanced, O-ring seals and an <br /> expendable drive point provided a watertight system to ensure sample integrity <br /> ' When the tool was advanced to the desired depth, extension rods were sent down the hole to <br /> brace the bottom of the sample screen as the tool casing was retracted When the casing was <br /> retracted, approximately 41 inches of screen with slot sizes of 0 004 inches was exposed Teflon <br /> tubing with a check valve attached to one end was inserted down the casing until it was immersed <br /> in groundwater Water was then pumped through the tubing and to the ground surface by <br /> ' oscillating the tubing up and down Groundwater samples were placed on ice and delivered under _ <br /> chain-of-custody documentation to Argon Laboratories for chemical analysis Following soil and <br /> groundwater sample collection, borings SB7, SB8, SB9, SB 10, SB 11, and SB 12 were backfilled <br /> ' with bentonite grout to the ground surface <br /> Groundwater was collected from soil borings SB7, SB8, SB9, SB 10, SB 11, SB 12, and CPT1 <br /> The groundwater samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg) <br /> and benzene, toluene, ethylbenzene, and xylenes (BTEX) utilizing EPA 8015 and 8020 <br /> w\149811reporbAAdd Inv doe 3 <br />