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ENCON <br /> Soil samples will be containerized in analysis-appropriate laboratory-supplied vials. For VOCs <br /> analysis, soil sub cores will be collected from the desired sampling point using a dedicated <br /> disposable plastic syringe and retained in two pre-weighed, laboratory-supplied, 40-milliter, <br /> sodium bisulfate-preserved and one methanol-preserved volatile organics analysis (VOA) vials in <br /> accordance with EPA Method 5035 sampling protocol. The vials will be sealed with Teflon-lined <br /> septum caps, labeled for identification, and stored in an iced cooler. <br /> Soil from each boring will be prepared for laboratory analysis. In addition, soil from the top of <br /> fine-grained intervals will be prepared for laboratory analysis. The remaining soil in the liners <br /> will be visually inspected for discoloration, monitored for odors, and classified in general <br /> accordance with the Unified Soil Classification System(USCS). Soil from select intervals will be <br /> placed in a sealable plastic bag and field-screened for volatile organics with a calibrated <br /> photoionization detector(PID). <br /> 5.6 Soil Gas Probe Construction <br /> Soil gas probe will be constructed within the boring locations after soil sampling has been <br /> completed. The boring will be advanced to the deepest desired sampling depth and a newt-inch <br /> diameter Nyla-flow tubing with a stainless-steel vapor implant at the terminal end will be inserted <br /> into the boring to the desired sampling depth and sand will be poured into the boring annulus to <br /> form an approximately 1-foot-long sand pack around the vapor implant. Approximately 1 foot of <br /> dry, granular bentonite will be placed atop the sand pack and the boring annulus will be backfilled <br /> with hydrated bentonite to the next desired sampling depth where a soil gas probe will be similarly <br /> constructed. <br /> Upon installation of the probe, the boring annulus will be backfilled with hydrated bentonite to <br /> approximately 6-inches bgs to form a seal. The outer casing will be withdrawn from the subsurface <br /> as the soil gas probe construction progresses.Each probe will be fitted with a valve on the sampling <br /> end of the tubing and labeled for identification. <br /> Soil gas samples will be collected by laboratory field personnel and analyzed by a State-certified <br /> laboratory. A shut-in test will be performed to identify potential leaks in the sampling train and <br /> fittings will be adjusted as necessary prior to purging and sampling each probe. <br /> The soil gas sampling probes will be allowed to equilibrate for 2 hours after installation, and <br /> sampling will be conducted by applying a vacuum to the probe and collecting the vapor samples. <br /> After each probe was allowed to equalize, the soil gas sample was extracted using a Xitech Model <br /> 1060H 1-Liter High Vac Bag Sampler vacuum pump and sampling box drawing air from the <br /> subsurface through the poly tubing and filling a Tedlar bag located inside the Sampler Box, <br /> upstream from the pump. The samples were collected after purging at least 7 pore volumes by the <br /> Field Technician. Approximately three purge volumes will be purged from each soil gas probe <br /> prior to sample collection. Each sample will be analyzed using a calibrated gas chromatograph / <br /> mass spectrometer(GC/MS) for analysis within 24 hours of sample collection. <br /> 8 <br />