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� r 02 August 2007 AGE-NC Project No, 07-1524 Page 2 of 4 SOIL PROBE BORING ADVANCEMENT On 24 July 2007, AGE advanced one soil boring (B-1) in the area of the former UST area. Soil boring B-1 was advanced utilizing a van-mounted Geoprobe 5400 direct-push probing unit equipped with 1.25-inch probing rods.The Geopbrobe advances soil probe borings using a hydraulic hammer to drive soil sampling tools to specified depths.Boring B-1 was advanced to a depth of 20 feet below surface grade (bsg). The location of soil boring B-1 is illustrated on Figure 2. As required for the procurement of a boring permit,the work scope and procedures were detailed in the AGE-prepared Limited Subsurface Phase IIInvestigation Work Plan dated 10 July 200,submitted to the SJCEHD. SOIL AND GROUND WATER SAMPLE COLLECTION Soil samples were collected at 5-foot intervals beginning at 5 feet bsg to total depth of the boring. Each sample was collected utilizing a 1.5-inch Geoprobe soil sampling assembly loaded with four six-inch stainless steel sleeves. After collection,the ends of the second stainless sleeve was covered with Teflon sheets, capped and sealed with tape. The sleeve was labeled with soil boring location, depth.time,date and sampler's initials and then placed in a chilled container. Soil sample duplicates were extruded into plastic bags and field-screened for the presence of organic vapors using an organic vapor meter(OVM), equipped with a photo-ionization detector(PID). A grab ground water sample was collected from the boring using a temporary PVC screen. A Geoprobe push-driven water sampling device was advanced two to three feet into the water bearing zone. Samples were collected using a Geoprobe water sampling assembly fitted with a new one-half inch 0.010-inch slotted temporary well screen. Each ground water sample was extracted using inertial action by lowering Teflon tubing through the hollow center of the push rods into the screen section. Sufficient sample was collected to fill four 40-m1 EPA-approved volatile organic analysis (VOA)vials and one 1-liter amber glass container.The groundwater sample containers were labeled with soil boring designation,date,time,and samplers initials and then placed in a chilled container. Following soil and ground water sample collection, the probe-boring location was backfilled to surface grade with Portland cement.Grouting of the borings was witnessed by representatives of the SJCEHD. SAMPLE ANALYSIS Soil and ground water samples were transported under chain-of-custody to Cal Tech Environmental Laboratories(CTEL),a California Department of Health Services-certified laboratory,and analyzed for the following: Advanced GeoEnvironmenta1,1nc.