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27 February 2019 AdvancedGeo <br /> AGE Project No. 08-1650 Environmental <br /> Page 4 of 6 0. <br /> 3.1. PILOT SOIL BORING ADVANCEMENT AND SOIL SAMPLE COLLECTION <br /> One pilot soil boring will be advanced to a total depth of 40 feet bsg utilizing a truck- or <br /> track-mounted, hollow-stem drill rig, equipped with 8.25-inch diameter hollow-stem <br /> augers. Relatively undisturbed soil samples will be collected from the soil boring at five- <br /> foot intervals beginning at 5 feet bsg using a California modified split-spoon sampler fitted <br /> with 2-inch diameter stainless steel sleeves. Upon removal from the sampler, sample <br /> sleeves will be separated, and the lithology characterized. Soil encountered in the boring <br /> will be visually classified by an AGE staff member in accordance with the Unified Soil <br /> Classification System (USCS). Additionally, soil samples will be field-screened for the <br /> presence of volatile organic compounds using an organic vapor meter (OVM) equipped <br /> with a photo-ionization detector (PID). Soil sample descriptions and OVM readings will be <br /> recorded on a log for each boring. <br /> 3.2. SOIL PROBE BORING ADVANCEMENT AND SAMPLE COLLECTION <br /> Soil borings will be advanced using a van mounted Geoprobe 5400 direct-push probing <br /> unit equipped with 1.25-inch probing rods. The Geoprobe advances soil probe borings <br /> using a hydraulic hammer to drive soil and groundwater sampling tools to specified <br /> depths. Borings will be advanced to total depths of approximately 30 feet bsg and <br /> between 65 and 75 feet bsg. The proposed boring locations are illustrated in Figures 2 <br /> and 3. Soil samples will be collected at discrete five- or ten-foot intervals beginning at five <br /> feet bsg in the shallow boring and at 40 feet bsg in the deep boring. Soil samples will be <br /> collected using a Geoprobe soil sampling assembly loaded with a two-foot acetate liner. <br /> Soil encountered in the borings will be visually classified by an AGE staff member in <br /> accordance with the USCS. Additionally, soil samples will be field-screened for the <br /> presence of volatile organic compounds using an OVM equipped with a PID. Soil sample <br /> descriptions and OVM readings will be recorded on a log for each boring. Soil samples <br /> will only be collected to characterize the lithology and identify the second water-bearing <br /> zone. <br /> 3.3. GRAB GROUNDWATER SAMPLE COLLECTION <br /> For collection of shallow and deep grab groundwater samples, soil borings will be <br /> advanced to the top of the groundwater table as identified by collection of a saturated soil <br /> sample or four feet below the identified second groundwater zone. Once groundwater has <br /> been encountered, a Geoprobe (or similar) push-driven water sampling device will be <br /> advanced four feet into the water-bearing zone. Grab groundwater samples will be <br /> collected using a Geoprobe water sampling assembly fitted with a pre-cleaned, one-inch <br /> diameter 0.01-slotted temporary well screen. Each groundwater sample will be extracted <br /> by dedicated disposable polyethylene tubing through the hollow center of the push rods <br /> into the screen section. <br />