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AdvancedGeo <br />Environmental <br />Ogg <br />13 June 2018 <br />AGE-NC Project No. 04-1239 <br />Page 4 of 6 <br />3.1.1. Soil-Vapor Boring Advancement and Sampling <br />Soil boring SV-1 will be advanced utilizing a 4-inch diameter stainless steel hand auger. <br />Upon reaching the total depth, soil boring SV-1 will be converted into semi-permanent <br />soil-vapor point using a three-inch long vapor implant attached to 1/4-inch diameter Teflon <br />tubing. The soil-vapor implant and tubing will be lowered to total depth of the boring (i.e. <br />6 1/2 feet bsg; filter pack material consisting of #2/12 sand will be placed from the bottom <br />of the borehole to a depth approximately one-foot above the vapor implant (i.e. 5 - 6 1/2 <br />ft). Following filter placement, approximately 1/2 foot of dry granular bentonite will be <br />placed above the filter pack (i.e. 4 1/2 - 5 ft). The remainder of the void space between the <br />tubing and the open borehole will be filled with a neat cement with 1-5% bentonite content <br />at depths between 1/2 - 4 1/2 feet bsg. The as-built construction of the soil-vapor sampling <br />well is depicted in Figure 5. <br />3.1.2. Soil Sampling <br />A soil sample will be collected at 5 feet bsg from soil boring SV-1 utilizing a 4-inch <br />diameter hand auger. The soil sample will be placed directly into a 6-inch brass sleeve. <br />The exposed ends of each brass sleeve will be covered with Teflon sheets, capped, and <br />sealed with tape. Each soil sample will be visually logged and classified by an AGE <br />geologist in accordance with the Unified Soil Classification System (USCS). Additionally, <br />the soil sample will be field screened for the presence of volatile organic compounds using <br />an organic vapor meter (OVM), equipped with a photo-ionization detector (PID). Soil <br />sample descriptions and OVM readings will be recorded on a log for each soil boring. <br />Following sample collection, each preserved sample sleeve will be labeled with the boring <br />location, depth, time, date, and sampler's initials. Appropriately sealed and labeled <br />samples will be placed in a chilled container and transported under chain of custody to a <br />State of California Department of Public Health (CDPH)-certified laboratory. Laboratory <br />reports of soil analysis, testing methods, laboratory quality assurance/quality control <br />(QA/QC) reports, and sample chain of custody documentation will be presented in a <br />report of findings and recommendations. <br />3.1.3. Soil-Vapor Sampling <br />Following soil-vapor well installations, a minimum 48-hour stabilization period will be <br />observed prior to soil vapor sample collection from the vapor point well location. A one- <br />liter Summa canister and a 6-liter purge canister will be connected together with a <br />dedicated and serialized sampling inlet manifold. The sampling inlet manifold will consist <br />of an air/vapor-tight valve; a particulate filter; a calibrated flow restrictor calibrated to 150 <br />milliliters per minute (ml/min), a stainless steel tee-fitting, two vacuum gauges at either <br />end of the controller and connections for both purge and sampling canisters (manifold <br />assembly). The soil vapor sampling assembly is depicted in Figure 6.