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08 November 2002 AGE-NC Project No.02-0918 Page 4 of 9 (EDB)and 1,2-dichIoroethane(1,2-DCA)in accordance with EPA methods 8260 Modified. The results of the soil sample laboratory analysis are presented in Section 4.2. 3.3. SOIL LOGGING After sample preservation, soil was extruded from the remaining sleeves and screened utilizing an organic vapor analyzer (OVA) equipped with a photo-ionization detector (PID: Thermo Environmental 580A, 10.0 eV,calibrated to isobutylene).The soil was also described in accordance with the Unified Soil CIassification System. Soil boring logs exhibiting soil profiles are depicted in Appendix A. 3.4. GRAB GROUND WATER COLLECTION AND ANALYSIS A`grab' ground water sample was also collected from boring B 1.After drilling to a depth of 50 feet bsg, the ground water sample was extracted by lowering a Teflon bailer down the center of the augers. The ground water sample was transferred into three laboratory-supplied, 40-m1 volatile organic analysis (VOA) vials containing 0.5 ml hydrochloric acid ('18%) as sample preservative. After collection, the samples were properly labeled, placed in a chilled container and transported under chain-of-custody to CTEL.The samples were analyzed for the same petroleum hydrocarbon products listed in Section 3.2. 3.5. MONITORING WELL INSTALLATION,DEVELOPMENT AND SURVEY Pilot borings 132,B3 and B4 were completed as ground water monitoring wells MW-1,MW-2 and MW-3,respectively,using 2-inch diameter schedule 40 PVC casing with 0.020-inch slotted screen installed from approximately 30 to 50 feet bsg and with blank casing extended to the surface.The filter pack(No. 3 Lonestar sand)was installed from approximately 28 to 50 feet bsg.A nominal 2- foot bentonite chip plug was then installed above the filter pack and hydrated.The remaining annular space was backfilled to within six inches of surface grade with portland cement.A traffic-rated well box (8-inch diameter) was installed over each well in accordance with San Joaquin County regulations. Monitoring well design specifications are depicted in Appendix A. Following well installation,the wells were developed in order to increase water Flow into the well and to minimize the amount of fine-grained sediment drawn into the well during pumping or bailing. On 27 August 2002, a California state-licensed survey engineer from Baumbach & Piazza Inc. Advanced GeoEnvironmental,Inc.