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11CV 8 \V9 A S S O C I A T E S I N C Selected soil samples were kept on ice and delivered under chain-of-custody documentation to State-certified Argon Laboratories Inc. (ELAP Cert. No. 2358) in Ceres, California for chemical analysis. Selected soil samples were analyzed by Argon for TPHg, TPHd, TPHss, benzene, toluene, ethyl benzene, and xylenes (BTEX) by EPA methods 8015/8020, and oxygenate fuel additives by EPA method 8260. The analytical results for soil samples are summarized in Table ' 1. Laboratory data sheets and chain-of-custody documentation are included in Appendix B. 223 Grab Groundwater Sampling and Analysis ' A groundwater sample was collected from boring SB2A at the depth groundwater was first encountered, approximately 32 feet below the surface of the angle boring. Taking into account the thirty degree angle of the soil boring, this corresponds to a water depth of approximately 27.7 feet bgs. A Geoprobe® Screen Point 15 Groundwater Sampler was threaded onto the leading end of the.Geoprobe after groundwater had been encountered. When the sampler was advanced, O-ring seals and an expendable drive point provided a watertight system to ensure sample integrity. When the tool was advanced to the desired depth, extension rods were sent downhole to brace the bottom of the sample screen as the tool casing was retracted. When the casing was retracted, approximately 41-inches of screen with slot sizes of 0.004 inches was exposed. Teflon tubing with a check valve attached to one end was inserted down the casing until it was immersed in groundwater. Water was then pumped through the tubing and to the ground surface by ' oscillating the tubing up and down. Following soil and groundwater sample collection, the boring was backfilled with neat cement grout to the ground surface. ' The groundwater sample was placed on ice and delivered under chain-of-custody documentation to Argon for chemical analysis. The groundwater sample was analyzed by Argon for TPHg, TPHd, TPHss, BTEX, and oxygenate fuel additives. The analytical results for groundwater sample are summarized in Table 2. Laboratory data sheets and chain-of-custody documentation are included in Appendix B. ' 224 Hollow Stem Auger Drilling Activities ' Hollow stem auger drilling was conducted on April 9, 2000, by V & W Drilling (State C57 license no. 720904). Soil boring MW4 was advanced to approximately 39 feet bgs and soil samples were collected at five-foot intervals. Soil boring MW4 was advanced and completed as ' a groundwater monitoring well. A field geologist logged drill cuttings and soil samples utilizing the Unified Soil Classification System. Descriptions of soil types encountered and sample collection intervals are included on the well construction log contained in Appendix A. w:1172951reportslsumiii.doc 3