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' 16 October 2014 AGE Project No. 13-2675 ' Page 3 of 9 ' BORING ADVANCEMENT On 03 October 2014, AGE advanced four soil borings (B4 through 137) at the subject ' property. Soil boring B4 was advanced in the location of the former dry cleaning facility, boring B5 was advanced in the location of the former potential in-ground petroleum tanks, boring 136 was advanced adjacent to the east side of the existing building at the site (Acapulco Gardens Restaurant), and boring B7 was advanced in the western portion of the property. Soil borings B4 through B6 were advanced to total depths of approximately three (3) feet bsg for soil-vapor sample collection and boring B7 was ' advanced to a total depth of 40 feet bsg for soil and groundwater sample collection. Soil boring locations are illustrated in Figure 1. ' Soil borings B4 through B7 were advanced to total depths utilizing a van-mounted, GeoProbe 5400 direct-push probing unit equipped with 1.25-inch diameter probing rods. The direct-push probing unit advances soil borings using a hydraulic hammer to drive ' sampling tools to specified depths. ' SOIL-VAPOR WELL INSTALLATION AND SAMPLING Soil-vapor samples were collected from borings 134 through B6 at depths of three (3) ' feet bsg. Prior to sampling, soil-vapor wells were installed within the soil borings previously advanced. ' For installation of the soil-vapor well, a temporary vapor-tip and five feet of '/4-inch Teflon tubing were lowered to the base of the previously advanced borehole; two feet of tubing was left outside the borehole for vapor sample collection. Once the tubing and ' vapor-tip were in place, a filter pack of #3 sand was placed from the bottom of the borehole to two feet bsg. Following placement of the filter pack, dry bentonite crumbles were placed atop the filter pack to one foot bsg. Thereafter, bentonite was placed and thydrated from one foot bsg to near surface grade to seal the vapor well from ambient air intrusion. ' One six-liter Summa canister was utilized for purging and the soil-vapor samples were collected in one-liter Summa canisters (TO-15). The sampling and purge canisters were ' connected together with a dedicated and serialized sampling inlet manifold. The sampling inlet manifold consisted of a vapor-tight valve; a particulate filter; a calibrated flow restrictor, calibrated to 150 milliliters per minute (ml/min); a stainless steel tee- fitting; two vacuum gauges at either end of the flow controller and connections for both purge and sampling canisters (manifold assembly). The manifold assemblies were attached to the tubing from the soil-vapor wells. The purge canister was attached to the ' end of the sampling manifold while the sample canisters were attached to the tee-fitting between the tubing and purge canister. Advanced GeoEnviron mental,Inc. 1