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06. 2.2.1 Soil Sampling Undisturbed soil samples were collected from SB-6 and SB-8. Soil samples were not collected from SB-7. In SB-6, soil samples were collected every five feet beginning at a depth of 20 feet bgs and until groundwater was encountered at 36 feet bgs. In SB-8 (remote fill location), soil samples were collected at 5 feet and 8.5 feet bgs. The sample collected at 8.5 feet consisted of soil from the interface of the buried concrete slab. Soil samples were collected by driving the Geoprobe sampler to the desired depth, retracting the piston tip into a sample tube lined with a one-inch diameter acetate sleeve and driving an additional two feet to displace the soil sample into the sleeve. The soil samples were then extracted from the borehole to the surface using the Geoprobe rig. A field geologist logged all k,.. soil samples for hydrogeologic and lithologic characteristics according to the Unified Soil Classification System. 2.2.2 Groundwater Grab Sampling Groundwater was encountered in SB-6 at a depth of 36 feet bgs. The soil boring was advanced to a total depth of 40 feet bgs. To collect the groundwater grab sample, a groundwater sampling device consisting of a steel inner core well screen nested inside a steel outer sampler sheath was inserted from 36 to 40 feet bgs. From this temporary well, a groundwater grab sample was collected by lowering a polyethylene tubing and check valve system down the hollow center of ,.., the drilling rod and into the groundwater column. Using an oscillating motion, groundwater was pumped to the surface and into laboratory supplied glassware. Each of the push-point soil borings was abandoned by filling them with a cement/bentonite grout. The grout was pumped from the surface to the bottom of the hole using a grout pump and tremie tube system. Surface pavement was restored to its existing condition. 2.2.3 Laboratory Analyses of Soil and Groundwater Grab Samples All soil and groundwater grab samples were contained, labeled, packaged and stored in an iced cooler for transport under chain-of-custody documentation to NEL Laboratories, a state of California Department of Health Services certified hazardous waste testing laboratory (#1192) located in Burbank, California. L From SB-6 (southwest corner of UST excavation), the soil samples collected from 20, 25, 30 .. and 35-feet bgs were submitted for laboratory analysis. Each of these soil samples was 7 w,.