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Ce0k9icdTecFinics Inc. Gubwy Page 2 Project No. 775.2 July 13, 1999 the former center UST. See Figure 2: Sketch.map for boring location. A hydropunch type groundwater sample will be collected from the boring. The soil boring will be drilled using an 8-inch outside diameter, continuous flight, hollow stem auger owned and operated by V&W Drilling (C57# 720904). The expected depth to groundwater is approximately 60 feet below ground surface, based on data from San Joaquin County Flood Control and Water Conservation District. The soil boring will be drilled to the,capillary .fringe. After the collection of the hydropunch sample,the borings will be closed by a neat cement grout trernied into the borehole. Soil boring permits will be secured as necessary and the local regulatory agency will be notified 48 hours prior to commencing work. The subsurface will be cleared of underground utilities by notifying Underground Service Alert. 2.1 Soil Sampling Procedure Soil samples will be collected for geological and analytical evaluation at 5-foot intervals. A boring log providing sediment description using the USCS and field observations will be maintained by a professional geologist working under the supervision of a registered geologist. Soil samples wi1l be collected in 6:0-inch brass liners using a 2.0 inch modified California split spoon sampler. All soil samples will 'be sealed with Teflon, capped with Teflon end caps, labeled and placed in a cooler at 4° Celsius for transport to the laboratory following Chain of Custody protocol. Since only selected soil samples will be submitted for laboratory analysis, a screening process will be used to gather additional information through field observation including: a sediment type, especially grain size and clay content moisture content • visible evidence of contamination, i.e., color change due to reduction of iron or discoloration from hydrocarbons and other pollutants a readings above background on a organic vapor meter (OVM) The OVM is a portable photo ionization detector that uses a 10.0 eV lamp to detect compounds with ionization potential below 10.0 eV (hydrocarbon range). 2.2 Hydropunch Sampling Procedure After the capillary fringe soil sample is collected from borehole, a hydropunch type groundwater sampling tool will be advanced into the saturated zone. The tool will then be retracted to expose the screen. A narrow diameter stainless steel bailer will be used to recover representative groundwater samples. Care will be taken to .minimize sample agitation from the initial filling of the bailer to the transfer of the sample to the VOA vial. Once the sample container is filled and capped, the bottle will be inverted, tapped, and checked for headspace bubbles. The sample container is identified and labeled with a unique designation, inserted into foam holders and placed in an ice chest cooled to 4°C for transport to the laboratory. All non-disposable sampling equipment is decontaminated using a steam cleaner before and between uses. Disposable gloves will be used while collecting all samples and will be changed with each sampling event. A bailer blank for each borehole will be collected prior to