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Boyett Petroleum ' 419 Main Street, Manteca, California ' Quarterly Groundwater Sampling Report ' March, 2001 ' Narrative On March 5, 2001, GeoAnalytical Laboratories, Inc., conducted field measurements, well pumping and groundwater sampling on eight (8) groundwater monitoring wells located at this site (Figures 1 and 2). ' Groundwater elevations were taken from four (8) wells prior to pumping (Table 1 & Appendix B). Monitoring wells MW-1 through MW-8 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 baiter. The samples were then labeled and placed in an ice chest cooled with 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 eight (8) water samples was EPA method 8260B for BTX&E (Benzene, Toluene, Xylene, and Ethyl-Benzene), oxygenates, Ethylene Dibromide (EDB), and 1,2-Dichloroethane (1,2-DCA), and EPA method GCFID (5030ILuft) for gasoline. ' The analytes and concentrations detected are listed in Table 2 of this report. Groundwater Gradient The water level measurements from eight (8) monitoring wells were used to construct a groundwater gradient reap (Figure 3). This quarter, the groundwater gradient trend is North 20° West with a downward slope of 0.0006 ft/ft. Historical groundwater gradient ' maps are provided for reference in Appendix C.