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I31 January 2002 AGE-NC Project No 95-0128 (' Page 6 of 8 abovegi ound stor age Baker tank into a vacuum truck (supplied by American Valley Waste OiI), the purged water was transported off-site under hazardous waste manifest to Industrial Service Oil Co Inc , a waste treatment facility located in Los Angeles, California Documentation and uniform - hazai dous waste manifest foi disposal of the pump test pw ged water ai e contained in Appendix I 3 5 GEO-TECHNICAL ANALYSIS RESULTS OF SOIL SAMPLES w generally encountered from a depth of approximately 30 feet to 60 feet Silty clay to sandy clay as g y P PP bsg in the two soil borings Soil borings and well completion logs are depicted in Appendix A Based upon soil samples submitted for geotechnical analysis, clay or clay with fine sand was encountered between 35 and 50 feet bsg The clay had a permeability range of 1X10-6 cm/sec to 3X10-7 cm/sec, ' and average porosity of 43% (Appendix J) ' 4 0. SUMMARY AND CONCLUSIONS The ground water table occurred within the well screen interval of the extraction well The most likely ' souice of the extracted ground water was from the silty clay and sandy clay with low permeability, encountered from 30 feet to 60 feet bsg ' The results fiom the Octobei 2001 aquifei ground water pumping test are • Ground water draw-down of at least 8 5 feet was observed in extraction well EW-1 following ' 720 minutes of continuous pumping(5 GPM),groundwater draw-down was observed in well VW-1 (located 5 feet to the west ) at 1 2•feet, well VW-4 (located 30 feet toward the west) at 0 45 feet,well EW-2 (located 15 feet toward the northeast) at 0 65 feet, wells MW-4 and ' MW-5(located 70 feet toward the northeast and 60 feet to the east,respectively) at 0 23 feet and in well vapor well VW-3 (located 25 feet toward the east) at 0 8 feet (Appendix C) ' A sem-logarithmic plot of ground water draw-down vs time was plotted to demonstrate relative stabilization of the ground water table within the network of observation monitoring points (Appendix E) • Utilizing a semi-logarithmic plot of ground water draw-down vs observation well distance fi om the pumping well, a best-ft line can be utilized to project a i adrus of intercept foi non- influence of approximately 100 feet at 5 GPM (Appendix F) ' Utilizing the Distance-Drawdown Method, a transmissivity was calculated at 380 ft2/day (equivalent to 2,840 gallons pei day/ft) and a storativity value was calculated at 0 043 ' (Appendix G) • Based on a tiansrnissi-vity value of 308 ft'/day and the exti action well screen thickness equal ' to 30 ft (screen interval at EW-1), a hydraulic conductivity value was calculated at 94 ft/day, or 0 03 cm/s (Appendix G), a hydraulic conductivity of 0 03 cm/s is consistent with a Advanced GeoEnvironmental Inc