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Mr. Jeffrey Wong <br /> Page 3 <br /> Drilling and Sampling <br /> A C-57 licensed drilling company will advance soil borings at the approximate locations shown <br /> on Figure 3 using a hollow stem auger drill rig. The soil boring located within the former <br /> tankpit will be advanced to a maximum depth corresponding to the historic low groundwater <br /> depth (approximately 80 feet) to evaluate the vertical limits of contamination. The other borings <br /> will be advanced to maximum depths of 45 to 50 feet unless field evidence of contamination <br /> indicates that shallower depths are sufficient to accomplish the objective of lateral definition. <br /> Upon completion, the soil borings will be backfilled with cement grout to ground surface. <br /> Soil samples will be collected at five foot intervals to total depth for lithologic identification and <br /> field screening for contamination. Soil samples will be collected with a split spoon sampler <br /> containing clean brass liners. Samples selected for laboratory analysis will be capped, labeled <br /> for identification and immediately placed in an ice-chest chilled to 4° C. <br /> A groundwater sample will also be collected from the central boring. The groundwater sample <br /> will be collected using a discrete sampling device (Hydropunch or equivalent) driven into the <br /> water bearing zone. In the event that the sampler screen clogs or for other reasons groundwater <br /> will not enter the device in suitable quantity, a grab sample will be collected through the rods <br /> using a disposable bailer. Water samples will be placed in appropriate containers, labeled and <br /> chilled as described above. <br /> Laboratory Analysis <br /> Selected soil samples will submitted under chain of custody protocol to a State-certified <br /> laboratory where they will be analyzed for total petroleum hydrocarbons as gasoline (TPHg) by <br /> EPA Method 8015 and for BTEX by EPA Method 8020. Selected soil samples will also be <br /> analyzed for gasoline oxygenate additives using EPA Method 8260. At a minimum, soil samples <br /> collected from intervals of significant lithologic change, those exhibiting significant field <br /> evidence of contamination and from the capillary fringe will be analyzed. In addition the <br /> deepest soil sample collected from the central boring will be analyzed for each of the analytes <br /> described above. <br /> The groundwater sample collected from the central boring will be submitted under chain of <br /> custody protocol to a State-certified laboratory for analysis of TPHg and BTEX using EPA <br /> Methods 8015 and 8020 and for oxygenates using EPA Method 8260. Depending upon field <br /> conditions, additional groundwater samples may also be analyzed. <br /> Reporting <br /> Following the receipt of analytical results a technical report describing the methods and results <br /> of this investigation will be submitted to PHS/EHD. The report will describe to the degree <br /> harrys\workplan <br />