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2.0 FIELD WORK SUMMARY In a work plan dated June 25, 1991, WESTON proposed installing monitoring well MW-4 in the narrow aileyway west of the restaurant building, approximately 60 feet downgradient from the former tank location as shown on Figure 1. The purpose of this well was to test the groundwater directly downgradient from the former tar.k location. WESTON also proposed collecting soil samples from the capillary fringe zone along the storm drain easement which is present west of the restaurant. The soil sample locations were designed intercept ltmateraa n he which might have moved preferentially down the storm drain g rocarbons o dwater. The work plan was approved by the EHD and field work commenced on July 2, 1991. It should be noted that one modification was made to the work plan procedure. An additional soil sample (SB-3) was collected from the capillary fringe zone (approximately 4.5 feet below ground surface, bgs) approximately eight feet northwest of MW-1. The purpose of this sample was to test the soil in a location that would have a high likelihood of hydrocarbon presence, ifsuch compounds existed in the vicinity near the former tank location. The new monitor well MWA was sampled on July 10 and July 16, 1991 to provide two independent analyses. The groundwater samples were scheduled for BTX&E, TPH-G, and colirorm bacteria analyses. Soil samples were collected on July 2, 1991 and scheduled for BTX&E and TPH-G analyses. All field work was performed under the direction of a Registered California Geologist. a comMete description of field work methodology including monitoring well specifications is presented in the Field Report, Appendix A. 3.0 ANALYTICAL RESULTS Analytical results for soil and groundwater are summarized in Table 1. The complete analytical reports are presented in Appendices B and C. All analyses were performed by the WESTON Analytics Laboratory which is certified by the State of California for the required analyses. 3.1 Soil Sample Results Although three soil samples (SB-1, SB-2 and SB-3)were submitted to the laboratory, only samples SB-1 and SB-3 were analyzea. SB-2 was not analyzed due to the addition of me SB-3 location to the work scope and the determination, based on proximity to the UST location (eight feet from MW-1 in center of former UST), that SB-3 was more likely to show hydrocarbon presence than SB-2 which was over 100 feet from the UST location. As shown in Table 1, the soil samples showed no detectable hydrocarbon presence except for toluene in sample SB-1 which is at the detection limit of 0.03 mg/kg. - 2 -