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Kennedy Jenks Consultants PRMLEGED & CONFIDENTIAL 2.0 FIELD ACTIVITIES Soil gas samples were collected from nine locations, Sampling Points SP#1 through SP#3 and SP#5 through SP#10 (Figure 3), on the Beckman Building property on 15 March 1996. Seven of these locations were outside of the Beckman Building. Sampling Points SP#9 and SP#10 were located inside the Beckman Building. At each of the seven outside locations, soil gas samples were collected at two different depths. The shallow soil gas samples were collected from approximately 5 feet below ground surface (bgs). The deep soil gas samples were collected from depths ranging from 18.5 to 25 feet bgs. Inside the Beckman Building, a single soil gas sample was collected from each of the two sampling locations at a depth of approximately 5 feet bgs. Soil gas sampling depths at each sampling location are listed in Table 1. The soil gas samples were collected by advancing a hydraulically driven 1-inch diameter sampling rod at each location to the desired depth. When the sampling depth was reached, the rod was withdrawn approximately 6-inches to create a void at the tip of the rod. A small vacuum pump was attached to the top of the sampling rod and a known volume of soil gas was extracted into a vial. Once filled with soil gas, the vial was recorded onto a chain of custody record and was analyzed immediately by TransGlobal Environmental Geochemistry, Inc. state certified onsite mobile laboratory (DOHS#1671). The soil gas samples and a blank gas sample were analyzed for halogenated volatile organic compounds (HVOCs) by EPA Method 8010. One duplicate soil gas sample was collected from Sampling Point SP#7 and was analyzed for HVOCs to assess the relative accuracy of the laboratory analyses. The sampling probe was washed with a phosphate-free detergent and rinsed with deionized water between use at each sampling location to minimize possible cross- communication of PCE or other HVOCs. The equipment rinse water and any soil generated from the soil gas sampling (investigation derived residuals) were collected in 5-gallon buckets and stored onsite for later profiling and disposal. After completion of the sampling and analysis at each location, the small borehole were filled with bentonite chips and hydrated with deionized water. Mr. Steven Sasson of SJCEHD was onsite to observe the abandonment of the borehole from Sampling Points SP#1 and SP#2 boreholes. The other boreholes were abandoned with his verbal approval. For the sampling locations outside the Beckman Building, the boreholes in the asphalt paving were patched with asphalt cold patch at each location. Inside the Beckman Building, 1 1/2-inch diameter concrete cores were drilled through the building's concrete slab on grade to allow advancement of the sampling rod and collection of the soil gas samples. At the completion of the sampling and analysis, the concrete cores were filled and leveled with a quick set , non-ferrous, non-shrink concrete grout. 4r5/5d 9:30 AM 3 952704.01 g:kpcst1955U52764.01 Uoei-MLdh