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25 September 1995 AGE-NC Project No 95-0125 Page 3 of 5 33 SOIL PROBING INSTALLATION On 26 June 1995, five soil probings were advanced to depths of ten feet, using AGE's van-mounted Geoprobe 5400 soil probing machine The location of the probing points is illustrated in Figure 2 Discrete soil samples were collected at depths of five, seven and ten feet using a piston-type Geoprobe soil sampling assembly All samples were field screened for the presence of organic vapors using a photo-ionization (PID Thermo Environmental instruments 580A) Boring logs, describing encountered soil characteristics, are included in Appendix B Samples were collected in clean 1 125 by 6-inch brass sleeves For each sample, the ends of the second sleeve were covered with Teflon sheets, capped and sealed with tape Samples were then placed in a chilled container and transported under chain-of-custody to McCapmbell Analytical, Inc (MAI)of Pacheco, California A total of six soil samples were analyzed for TPH-g and BTE&X in accordance with EPA methods 5030/8015m and 8020, respectively Sampling equipment was decontaminated in a non-phosphate detergent solution, rinsed twice with clean water prior to each sampling run iIn addition to sort samples, a grab ground water sample was obtained from probing The grab sample was collected at a depth of approximately six feet using a peristaltic pump and clean tygon tube The sample was collected in a Miter amber bottle, stored in a chilled container and transported under chain-of-custody to MAI The grab ground water sample was analyzed for TPH (as gasoline and diesel) and BTE&X in accordance with EPA methods 5030/8015m and 602, respectively Upon completion of sampling, each probing hole was backfilled with bentonite 3�a d-ped-wrth Bement 4.0. FINDINGS 4 1 GROUND WATER ELEVATION AND GRADIENT DIRECTION When measured on 26 June 1995, the depth to ground water at the site ranged from 6 to 7 feet bsg The relative elevation of ground water in each well was calculated by subtracting the ground water depth from the surveyed casing elevations, casing elevations were surveyed relative to MW-1, which Iwas assigned an arbitrary elevation of 100 00 feet Table 1 depicts the ground water elevations A 2-foot increase in ground water elevation was detected between the November 1994 and June 1995 samplings Figure 3 illustrates the relative ground water elevations at the site, based upon data collected during the June 1995 sampling Ground water flow in the area is to the northwest, with a small ndge evident