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1 Boyett Petroleum ' 419 Main Stree4 Manteca, California ' Quarterly Groundwater Sampling Report June, 2000 Narrative 1 On June 23, 2000, GeoAnalytical Laboratories, Inc., conducted field measurements, well pumping and groundwater sampling on four (4) groundwater monitoring wells located at this site (Figures 1 and 2). 1 Groundwater elevations were taken from four (4) wells prior to pumping (Table 1 & Appendix B). Monitoring wells MW-1 through MW-4 were evacuated by means of a ' steam-cleaned, stainless steel bladder type pump. During the three (3) volume pump down of each well, samples were collected to measure field pH, electrical conductivity and temperature (Table 3 & Appendix B). Once stability was achieved, a minimum of three (3)well volumes were removed and samples were collected with a disposable bailer. The samples were then labeled and placed in an ice chest cooled with Blue Ice®. ' The samples were then logged on a Chain of Custody(Appendix A) and transported to the State-certified laboratory, GeoAnalytical Laboratory Inc., in Modesto, California. The analysis requested for the four (4) water samples was EPA method 8021B for BTX&E (Benzene, Toluene, Xylene, and Ethyl-Benzene) and MTBE (Methyl Tertiary Butyl Ether) and EPA method GCFID (5030/Luft) for gasoline. The analytes and concentrations detected are listed in Table 2 of this report. 1 Groundwater Gradient The water level measurements from three (3) monitoring wells (MW-1, MW-2, MW-3) ' were used to construct a groundwater gradient map (Figure 3). This quarter, the groundwater gradient trend is South 40° East with a downward slope of 0.0021 ft/ft. Since the sampling event in March 2000, the groundwater has fallen an average of 1.5 ' feet. Historical groundwater gradient maps are provided for reference in Appendix C. 1 1 i 1 1