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3.2.2 Discrete Ground Water Sample Collection <br /> A discrete ground water samples will be collected from each soil boring Soil boring drilling and <br /> sampling will be halted upon encountering the zone of saturation After drilling to the prescribed <br /> ' depth, the auger flights will be left in the borehole and the ground water allowed to rise in the <br /> hollow auger stem A bailer will then be lowered into the auger stem for the collection of a <br /> ' ground water sample Standard ground water sampling protocol will be used in the collection and <br /> handling of the sample to preserve its integrity <br /> ' Ground water samples collected from soil bonngs during this phase of the investigation will be <br /> field analyzed by PID headspace analysis The ground water will be collected in clean disposable <br /> polyethylene bailers and then transferred to clean 500 milliliter sample bottles or Jars Each Jar <br /> ' will be filled approximately 314 full with sample water and immediately capped The sample will <br /> then be agitated by hand to release volatile components to the headspace atmosphere The probe <br /> of the PID will be inserted into the headspace of the Jar and the subsequent reading recorded on <br /> ' the appropriate field log This methodology has indicated a high sensitivity to volatile gasoline <br /> constituents and is believed to be the most cost-effective approach to field screening of ground <br /> water samples <br /> Upon termination of the soil boring and round water sampling, each boring that is not to be <br /> g g <br /> converted to a monitoring well will be properly abandoned Bentonite chips or pellets will be N° <br /> tplaced into each soil boring that encounters ground water to a thickness equal to the thickness of <br /> the water layer within the boring The remainder of the soil boring will be sealed with a <br /> cement/bentonite slurry tremmied into the boring as described in Section 3 2 1 The conversion of <br /> soil borings to monitoring wells is described in Section 3 3 1 <br /> ' 3.2.3 Laboratory Analysis of Soil Samples <br /> All soil samples collected for laboratory analysis will be stored in a cooler chilled to 4° Celsius <br /> and shipped under strict chain of custody protocol to the analytical laboratory The samples will <br /> be analyzed in Modesto, California by GeoAnalytical Laboratories, a California State certified <br /> analytical laboratory for the following constituents <br /> ' • TPH - gasoline, Method 5030/LUFT <br /> detection limit 10 mg/Kg <br /> ' . Benzene Toluene Ethyl Benzene and Total Xylenes (BTEX), EPA Method od 8020 <br /> detection limits 5 0 µg/Kg <br /> 3.3 Monitoring Well Installation and Sampling <br /> ' AGS proposes to install three ground water monitoring wells to determine the lateral extent of <br /> ground water contamination caused by the release of petroleum hydrocarbons at the site A <br /> fourth monitoring well will be installed to ascertain possible vertical migration of contamination at <br /> the site <br /> American Geological Services,Inc <br /> CA95DE-029 <br /> 9 <br />