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9 <br /> ATTACHMENT A <br /> SOIL BORING INSTALLATION FIELD AND LABORATORY <br /> PROCEDURES <br /> Exploratory Sampling <br /> Three soil borings will be drilled using a Simul-Probe®, Enviro-Core or similar driven probe <br /> technology to collect discrete soil and discrete groundwater samples. All down-hole equipment <br /> will be steam cleaned prior to drilling. Representative undisturbed soil samples will be collected <br /> from the boring for geologic logging,field hydrocarbon vapor screening and laboratory analysis. <br /> Soil samples will be logged by a SECOR geologist using the Unified Soil Classification System. <br /> The borings will be drilled to a total depth of approximately 40 feet below ground surface (bgs). <br /> Continuous core sampling will be conducted in the boring proposed directly east of the site. Soil <br /> samples will be collected from the other two proposed borings at 5-foot depth intervals. At each <br /> sampling interval, the middle sample liner will be retained for chemical analysis. The ends of <br /> the liner will be sealed with Teflon®tape and plastic end caps, and placed in a chilled container <br /> for delivery to a state-certified analytical laboratory along with appropriate chain-of-custody <br /> documentation. <br /> Organic Vapor Procedures <br /> Soil samples collected at each interval will be field screened for VOCs using head space analysis <br /> and a photo-ionization detector (PID) or flame ionization detector (FID). The test procedure <br /> involves measuring approximately 30 grams from an undisturbed soil sample, and placing this <br /> subsample in a ziplock type bag. After the soil is allowed to equilibrate for approximately <br /> 20 minutes, the probe tip of the PID or FID is inserted into the bag. The highest measured <br /> concentrations of VOCs within the head space of the bag will be recorded on the boring log <br /> (Attachment B). PID and FID readings are useful for indicating relative levels of contamination, <br /> but cannot be used to evaluate hydrocarbon levels with the confidence of laboratory analyses. <br /> Laboratory Procedures <br /> Soil and groundwater samples will be submitted under standard chain-of-custody protocols to <br /> a California State-certified laboratory. The samples will be analyzed for total purgeable <br /> petroleum hydrocarbons calculated as gasoline (TPH-g), benzene, toluene, ethylbenzene and <br /> xylenes,and fuel additives(including MtBE,DIPE,ETBE,and TAME),by EPA Methods 8015 <br /> (modified), 8020, and 8260. <br />