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GEOMATRIX <br /> that the travel blank was analyzed in a sequence after samples with high detections of those <br /> compounds and concluded that the detections in the travel blank were carryover from the other <br /> samples and are not representative of constituents in the travel blank <br /> No analyzed constituents were detected in the laboratory method blanks Recoveries of <br /> surrogate spikes were within laboratory quality control limits Samples MW3-6, MW3-3, and <br /> MW3-2 included detections of oxygenates at concentrations exceeding the linear range The <br /> samples were diluted by APPL, and the constituents detected at concentrations exceeding the <br />' linear range were reanalyzed The reanalyzed concentrations were reported <br /> 3.2.2 Analytical Results <br /> Analytical results for quarterly monitoring parameters and selected parameters requested by <br /> SJCDEH are presented in Table 3 Laboratory analytical reports are included in Appendix B <br /> 1 Analytical results are consistent with historical results for wells MW3-1, MW3-2, and MW3-3 <br /> This is the first sampling event for monitonng wells MW3-4, MW3-5, and MW3-6 <br /> Groundwater samples from monitoring wells MW3-1, MW3-2, MW3-3, and MW3-6 are <br /> impacted with TPHg and BTEX Groundwater sampled from monitoring wells MW3-4 and <br /> MW3-5 have no detected TPHg or BTEX Oxygenates DIPE, EtBE, MtBE, and tAME were not <br /> detected in any of the new wells and have not been detected in the old wells Dissolved lead was <br />' not detected in MW3-4, but was detected at a concentration slightly greater than the practical <br /> quantization limit of 3 micrograms per liter in MW3-5 and MW3-6 The highest concentrations <br /> of TPHg and benzene were detected in the groundwater sample from MW3-6 The highest <br /> concentrations of toluene, ethylbenzene, and xylenes were detected in the groundwater sample <br /> from MW3-2 The benzene concentration in MW3-6 is higher than previously reported benzene <br />' concentrations in site monitoring wells. APPL was contacted regarding the benzene <br /> concentration APPL checked for carryover or other quality control issues and found none <br /> 4.0 DISCUSSION <br />' During previous sampling events, groundwater was purged from the site monitoring wells using <br /> a vacuum truck and dedicated stinger in each well This purge method would tend to flush <br />' fine-grained formation particles from the nearby formation PHC compounds tend to adhere to <br /> fine-grained soil particles The fine-grained soil particles have not been flushed from the new <br /> groundwater wells The relatively high concentrations of TPHg and benzene in MW3-6 may be <br />' due to abundant fines being removed from the well during the initial sampling event in that well <br /> The concentrations of PHC will continue to be assessed during future sampling events <br /> 1 <br /> I TROJECTWOM6437 00016437-06 doc 4 <br />