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■ ■ except those acquired from EB11 (currently on hold pending analysis) . Analysis conducted to date revealed that all samples were free of detectable concentrations of Total Lead (detection limit 2 .5 ppm) . ' Each of the soil borings was advanced to a depth of 59 feet bgs, with the deepest soil samples acquired from 59 .0--60 . 5 feet. Groundwater was encountered at 59 feet in EB-8 and 58. 5 feet in FB-11 . The borings were se ed with bentonite from the bottom ' of the borehole to one foot belo the water level and then filled with grout cement to the ground surface. 7 ' The borings advanced on June 22-25 and 29, 1992 were converted to 2" inside-diameter groundwater monitoring wells constructed of threaded, Schedule 40 PVC risers attached to 0 . 020" slotted ' PVC well screen. The screened interval was extended five feet above the water table and the annular space around the screen was filled with ##3 Monterey Silica Sand. The annular pack was then covered by a two foot thick bentonite seal to protect groundwater from surface water infiltration. Cement was added from the top of the bentonite seal to 0 . 5 feet bgs followed by concrete aggregate to grade. Each well was then covered with a locking traffic box. Construction details for each well are presented graphically in Appendix A. Following construction of the monitoring wells, each was allowed to equilibrate for a period of at least 48 hours. Following this period, the depth to water and total well depth were measured with an electric water level meter and the volume of water contained in each well casing was computed. Each well was developed using a vented surge block to release and draw fines ( silts, clays, and fine sands ) into the well by forcing water in and out of the screen slots and adjacent annular pack. Each well was then purged using a clean bailer until the ground- water was free of sediment and other grit material, and the pH, conductivity, and temperature were stabilized. Measurements of pH, conductivity, and temperature were recorded and are presented in Appendix A. Samples from each developed well were obtained in a clean, disposable, polyethylene bailer lowered into the well to a point immediately below the water surface. Each water sample was transferred into three ( 3 ) amber glass sample bottles and two ( 2 ) Volatile Organic Analysis (VOA) vials . Each container was promptly sealed with a teflon-lined screw cap, labeled, placed on blue ice, and transported to a California--state certified hazardous waste analytical laboratory under chain of custody. Subsequent analyses were conducted for TPH-G and BTEX using EPA Methods 5030/8015-8020 (602) ; TPH-D using EPA Methods 3510/ 8015, HVOs using EPA Method 601 ; and Total and Fecal Coliforms . The report of laboratory analyses appears in Appendix B. These 6. ■