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Q <br /> A S S O C I A T E S I N C <br /> l <br /> 2_1 Drillina Activities <br /> ' On November 15 and 16, 2001, an ATC geologist supervised the advancement of three soil <br /> borings to approximately 54 to 55 feet bgs. A site plan with soil boring locations is shown on <br /> Figure 2. Woodward Drilling, California License C57 710079, advanced the borings utilizing a <br /> hollow stem auger drill rig. Soil samples were collected from borings MW 1, MW2, and MW3 at <br /> five-foot intervals in stainless steel sampling tubes. The cored samples and drill cuttings were <br /> ' characterized for soil type, moisture content, and visual evidence of petroleum hydrocarbons. A <br /> photo-ionization detector (PID) was used as a field-screening device for the detection of <br /> petroleum hydrocarbon vapors in drill cuttings and cored samples. A field geologist logged drill <br /> ' cuttings and soil samples utilizing the Unified Soil Classification System. Descriptions of soil <br /> types encountered and sample collection intervals are included on the boring/well logs contained <br /> in Appendix A. Soil borings MW 1, MW2, and MW3 were then completed as groundwater <br /> ' monitoring wells. Drill cuttings were temporarily stored on site in 55-gallon DOT approved steel <br /> drums. <br /> 2_2 Soil Sample Analysis <br /> Selected soil samples were kept on ice and delivered under chain-of-custody documentation to <br /> State-certified Argon Laboratories Inc. (FLAP Cert. No. 2359) in Ceres, California for chemical <br /> analysis. Selected soil samples were analyzed by Argon Laboratories for TPHg by EPA method <br /> 8015 modified; BTEX by EPA method 8020; methyl tertiary butyl ether (MTBE), tertiary amyl <br /> methyl ether (TAME), tertiary butyl ether (TBA), ethyl tertiary butyl ether (ETBE), di-isopropyl <br /> ether (DIPE), 1,2-dichloroethane (1,2-DCA), and ethyl dibromide (EDB) by EPA method 8260; <br /> and total lead. The analytical results for soil samples are summarized in Table 1. Laboratory data <br /> ' sheets and chain-of-custody documentation are included in Appendix B. <br /> 2_3 Groundwater Monitoring Well Construction <br /> Soil borings MW 1, MW2, and MW3 were completed as groundwater monitoring wells to assess <br /> ' impacted groundwater beneath the site and to provide measurement points for the determination <br /> of groundwater flow direction and hydraulic gradient. The wells were surveyed to an arbitrary <br /> elevation and survey results are contained in Table 2. <br /> Each well was constructed with 2-inch PVC casing to depths of approximately 54 to 55 feet bgs. <br /> The screened interval of each well was positioned from approximately 5 feet above to 15 feet <br /> ' below the encountered water table to allow for seasonal water level fluctuations. The screen slot <br /> size is 0.010-inch and the wells were surge blocked to ensure an adequate sand pack was in place. <br /> Well construction details are depicted on the boring/well logs contained in Appendix A. <br /> r0/ <br /> 1 <br /> w:192054.000I UepoM\sumii.doc 3 <br />