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' 24 March 2015 • AGE Project No. 14-3325 ' Page 2 of 5 ' During the investigation, AGE advanced four (4) soil borings in the central region of the property, and two (2) soil-vapor borings along the southern property boundary. Soil and soil-vapor boring locations and designations are depicted on Figure 2. tSOIL PROBE BORING ADVANCEMENT ' On 04 March 2015, a total of six borings (SB1-SB1, SV1, SV2) were advanced at the subject property. Borings were advanced under SJCEHD Permit SR# 71612 (Appendix ' A). All borings were advanced within the central region of the property, and along the southern property boundary. Approximate locations of each of the borings is illustrated in Figure 2. ' Soil borings were advanced to a total a depth of approximately 20 feet below surface grade (bsg). Soil-vapor borings were advanced to a total depths of approximately 8 feet ' bsg. Borings were advanced utilizing an AMS Powerprobe 9600 direct push drilling rig equipped with 1.25-inch diameter probing rods. ' SOIL-VAPOR SAMPLE COLLECTION ' Soil-vapor samples were collected at depths of approximately 8 feet bsg in borings SV-1 and SV-2 using a Geoprobe soil-vapor sampling assembly. An expendable vapor point was placed into a point holder at the bottom of an assembly of 1.25-inch diameter ' hollow rods. The assembly was then advanced to the specified depth (i.e. 5 feet bsg) and retracted approximately twelve inches in order to disengage the bottom expendable point and expose a column of strata from which soil-vapor could be extracted. Single ' use, '/4-inch diameter disposable polyethylene tubing was then attached to a tubing adapter equipped with an O-ring to ensure a vacuum-tight seal. The adapter assembly was lowered through the center of the hollow drive rods to the specified depth and ' secured by threading into the expendable vapor point holder. Above ground, the surface around the soil-vapor sampler was sealed with bentonite ' powder and hydrated to prevent ambient air intrusion. Soil- vapor sample collection was conducted using 1-liter Tedlar bags. To ensure that a reliable soil-vapor sample was collected with no ambient air breakthrough down the probe rod, AGE erected a plastic ' enclosure over the probe rod, and applied an appropriate amount (approximately 6 to 8 ounces) of Isopropyl Alcohol (IPA) as a tracer to a towel. The wetted towel was completely wrapped around the base of the probe rod where it contacted the surface ' and the bentonite seal. The end of the polyethylene tubing was attached by a two-way inlet port to a Tedlar bag ' placed inside an SKC Vac-U-Chamber (lung box) vacuum chamber. A vacuum pump attached to a purge port of the vacuum chamber was then used to purge the exposed soil column, through the sampling tubing and inlet port, for one minute prior to sample 1 Advanced GeoEnvironmen[al,Inc. 1