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1 <br /> Geological Technics Inc P age 4 <br /> Groundwater Monitonng Report <br /> Project No 723 2 <br /> January 19,2004 <br />' The sampling technician wore disposable gloves while collecting all samples <br />' A chain of custody document, listing all samples collected and their intended analyses, <br /> accompanied the samples from the field to the laboratory, thereby providing a means to <br /> track the movement of the samples and ensure their integrity <br /> 1.3 Laboratory Analyses <br /> The groundwater samples collected on November 26, 2003, were delivered to Sherwood <br /> Labs of Hilmar, California (certification #1400) for analyses of <br />' ❑ Benzene, Toluene, Ethyl Benzene, and Xylene (BTEX), MTBE, by EPA method 8020 <br /> ❑ Total Petroleum Hydrocarbons as Gasoline (TPH-G) by EPA method 5030/8015(M) <br /> Sherwood forwarded well MW-201 samples to Castle Analytical Laboratory (Department of <br /> Health Services Certification No 2480) of Atwater, California, for analysis of <br /> • Oxygenated Fuel Compounds (MTBE, DIPS, ETBE, TAME & TBA) by method 8260 <br /> The detection limits for the above analyses are listed in Table 2 of Appendix A, while the <br /> lab analytical results are presented in Appendix B <br /> As required under AB2886� groundwater elevation and laboratory data were submitted <br /> q <br /> electronically to GeoTracker on January 13, 2004 and December 11, 2003 - confirmation <br /> numbers 41681 10489 & 5144245207, respectively <br /> ' The soil data from the November 20 — 26 soil borings (MW-7 through MW-9) was <br /> successfully uploaded to GeoTracker on January 13, 2004 - confirmation numbers <br /> 6994009196 & 4156458973 <br /> ' 2.0 FINDINGS AND DISCUSSION <br /> ' The results of the groundwater sample analysis show the following <br /> ❑ Review of the historic groundwater elevations show that groundwater levels experience <br /> seasonal fluctuations from the mid 1990s to spring 2000 but have been decreasing <br /> steadily with each seasonal cycle since spring 2000 <br /> ❑ The concentrations of BTEX and TPH-G continue to fluctuate in individual monitoring <br /> wells from one sampling event to the next However, there is a general trend of <br /> ' concentrations tracking the groundwater elevations <br /> ❑ Intenriediate well MW-101 continues to contain BTEX & TPH-G, but concentrations <br /> ' continue to fluctuate from one sampling event to the next <br /> ❑ Deep well MW-201 contained xylene at a concentration (0 3 ug/1) dust at the laboratory <br /> reporting limit The contamination is probably a drilling artifact created by the use of <br /> mud rotary drilling It is noted that the contaminant concentrations in MW-201 have <br />