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modifications by PHS/EHD. Additionally, modifications to the letter addendum were made in the field with the approval of PHS/EHD. 2_1 Phase One The scope of work completed in phase one included obtaining permits, advancing five soil borings . using direct push technology, soil and grab groundwater sampling, and the laboratory analysis of selected soil and groundwater samples. 2.1.1 Drilling Activities On October 29, 1997, a Smith Technology geologist supervised the advancement of two soil borings to 30 feet bgs and three soil borings to 25 feet bgs. A site plan showing soil boring locations is included as Figure 2. Fisch Environmental, California License C57 683865, advanced the borings using a truck mounted Geoprobe® narrow diameter rig employing direct push technology. Soil samples were collected at five-foot intervals in acetate sampling tubes beginning at five feet below the ground surface and were described according to the Unified Soil Classification System. Descriptions of soil types encountered and sample collection intervals are presented on the boring logs contained in Appendix A. 2.1.2 Soil Sampling and Analysis Each soil sample was field screened with a Photoionization Detector (PID) for the presence of volatile organic compounds. No petroleum hydrocarbons were observed during field activities in borings SBI, SB2, SB3, SB4, or SB5. The PID readings from soil samples SB2-25 and SB3-5 were 11 and 9 parts per million (ppm), respectively. None of the other PID readings from the collected soil samples exceeded background levels of approximately 0 to 2 parts per million (ppm). Sample tubes were then sealed at each end using Teflon tape and plastic end caps, labeled, and placed on ice. Selected soil samples were kept on ice and delivered under chain-of-custody documentation to a State-certified American Environmental Network (AEN) laboratory (DOHS .- Cert. No. 1172) for chemical analysis. Field notes and PID readings are contained in Appendix B. Selected soil samples were analyzed by AEN for total petroleum hydrocarbons as gasoline, u (TPHg), benzene, toluene, ethylbenzene, xylenes (BTEX), oxygenate fuel additives, and total lead. The analytical results for soil samples are summarized in Table 1. Laboratory data sheets and chain-of-custody documentation are included in Appendix C. 2.1.3 Groundwater Sampling and Analysis One groundwater sample was collected from each boring at the depth groundwater was first encountered, approximately 19 feet bgs. A Geoprobe® Screen Point 15 Groundwater Sampler was threaded onto the leading end of the Geoprobe after groundwater had been encountered. w:\,90954190954.03\repofU\psi.d- 2 s SMTH u