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it 2.2 Drilling Activities and Sample Collection On September 24 and October 2, 1996, Smith Technologysupervised pe sed the advancement of nine soil borings (SB-I through SB-7 and FPB-1 and FPB-2) at the site. Ron Rowe of PHS/EHD observed much of the field activities conducted by Smith Technology. Drilling was conducted by Vironex Environmental Field Services (State C57 license no. 662116 utilizing Direct Push Technology, specifically the Geoprobe Systems Model 5400 sampling system. Soil samples were collected for lithologic, chemical, and geophysical analyses and soil vapor and groundwater samples were collected for chemical analyses. A field geologist was present to log all drill cuttings and soil samples utilizing the Unified Soil Classification System. Descriptions of soil types encountered and sample collection intervals were recorded on boring logs included 'in Appendix I. Generally, soil samples were collected continuously from the ground surface to a depth of 4 feet using a 1.5-inch inside diameter metal sampler, 4-feet in length and containing a 4-foot acetate sleeve. This sampler was also used to collect samples for geophysical analyses from deeper depths. Subsequent soil samples were collected at 5-foot intervals (beginning at 5 feet below ground surface (bgs)) using a 1-inch diameter metal sampler, 24 inches in length containing four 6-inch brass tubes. The soil samples were characterized for soil type, moisture content, and visual evidence of petroleum contamination. A photoionization detector (PID) was used as a field screening device for the detection of petroleum hydrocarbon vapors in the samples. Soil samples were labeled and placed immediately in a cooler with ice. Prior to collection of grab groundwater samples from each boring, a soil vapor sample was collected utilizing a vacuum pump on the drilling vehicle and a passive collection system. During drilling activities groundwater was initially encountered at approximately 7 to 10 feet bgs and stabilized at approximately 7.5 feet bgs. Thus, a drive point sampler was driven to the depth of the capillary fringe (generally at S feet bgs) and the sampler was pulled back up to 2 feet exposing all or part of the 2-foot screen in the sampler. Subsequently, a clean plastic tube was inserted into the sampler to the screen interval, and the top of the tube was connected to a tedlar bag inside a plastic case. The plastic case was sealed, and the air inside the case was evacuated utilizing the vacuum pump on the drilling vehicle, creating negative pressure inside the case and the tedlar bag. The vacuum pump was shut off and the line to the case L� closed at the desired pressure, and then the plastic tube was opened to the tedlar bag, and the bag allowed to fill with soil vapor from the formation. Upon discussion with Ron Rowe, it was decided that evacuation of the plastic tubing prior to connecting to the tedlar bag was N unnecessary due the very small volume of the tubing versus the volume of the tedlar bag. The wA95122TIumerpt 3 •