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elevated in several wells, ranging from 43 2 ppb in VM-7 to 81 3 ppb in VM-3 (Appendix B) Figure 5 is an isocontour map of dissolved lead, and it appears that the highest concentrations are located in the central portion of the site southeast of the former dispenser island However, the distribution of lead does not resemble the TPH-g distribution (c f Figure 4) Thus, the source of the lead is not clearly apparent, nor is,it clear whether lead is restricted to the site or is elevated throughout the area 4.3 Electronic Data Uploading SJCEHD has pointed out that not all laboratory reports have been submitted electronically to the State Geotracker program, and requested that the electronic data file (EDF) for the site be brought up to date This task was accomplished during the quarter, seven missing laboratory reports were obtained from the laboratory and uploaded to Geotracker 5.0 REMEDIATION ACTIVITIES Soil remediation was initiated during the fourth quarter of 2005 Initial testing occurred on November 22 and the soil vapor concentration was measured with a portable photo-ionization detector(PID) Full operation commenced on December 12 and was witnessed by the San Joaquin Valley Air Pollution Control District(full operation could not take place until the air pollution office witnessed the startup and sampling) Thereafter the vapor extraction unit was monitored weekly and PID measurements were recorded (Table 4) In addition, laboratory . samples were collected in Tedlar,sample bags from the inlet and'outlet ports of the unit for quantitative analysis of hydrocarbon vapors by the laboratory Samples were collected on December 12 and January 12 (Table 5) The initial influent PID reading of 550 parts per million (ppm)was not sustained, and the concentration declined steadily through the end of January to about 200 ppm Effluent readings remained in the 10-14 ppm range after the initial reading of 20 ppm The laboratory reported Total Petroleum Hydrocarbon vapor concentrations of 2,010 and 850 parts per million by weight in the samples collected on December 12 and January 12 (Table 5 and Appendix C) Converting these concentrations to parts per million by volume (ppmv) yields concentrations of 571 ppm and 242 ppm (Table 5) Both of these are somewhat higher than the concentrations measured in the field with the PID Assuming that the laboratory concentrations are representative averages for the period between measurements, multiplying these concentrations by the average air flow rates (which are automatically recorded by the extraction unit), it is possible to calculate the daily and weekly hydrocarbon removal rates Through January 27, a total of approximately 427 pounds of hydrocarbons had been removed (Table 4) Table 4 also shows the number of hours during which the extraction system was in operation The system operated continuously from December 29 through January 5 Processing was interrupted occasionally either when the unit ran out of supplemental fuel or from intermittent power outages i4