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' trom MW-8 was also analyzed by Method 160 1 for total dissolved solids, by USEPA Method 8080 for Chlorinated Pesticides and PCBs, by USEPA Method 8240 for volatile organics, and by USEPA Method 300 0 for bromide, sulfates, and nitrate as nitrogen All samples were submitted to the District's laboratory along with the ' appropriate Chain-of-Custody forms Quality control samples were collected to provide a check on the sampling, analysis, and shipping procedures One duplicate sample was collected from MW-8 ' and submitted to the District's laboratory for identical analyses as the original sample One split sample was collected firm MW-9 and submitted to an outside non-District ' laboratory for identical analyses as the original sample to provide a check on the analytical procedures One 40 milliliter (mL) via[ trip blank was submitted to the ' District's laboratory and one 40 mL trip blank was submitted to the non-District laboratory for BTEX analyses to provide a check on shipping procedures In addition, 4 liters of groundwater were collected from MW-8 and submitted to Emerging Technologies, Inc, for bench-scale testing in support of the proposed remediation Results of the bench-scale test are not included in this quarterly ' monitoring report but will be provided in a separate report 4 3 Analytical Results Analytical results from third quarter 1994 sampling are summarized in Table 2 The laboratory data sheets are provided in the Appendix The quality control results ' are not included in Table 2, but are included in the Appendix The duplicate and trip blank quality control sample results confirmed that the samples had been ' collected, shipped, and analyzed appropriately Based on the data collected to date, the approximate petroleum hydrocarbon plume delineation €s shown on Figure 4-3 ' A summary of analytical results from the quarterly monitoring events since the third quarter 1993 are also presented in Table 2 The third quarter 1994 sampling results are consistent with the previous quarterly ' sampling results with the exception of the analytical results from MW-9 The sampling results from the fourth quarter 1993, first quarter 1994, and third quarter ' 1994 indicated traces of benzene and TPH-g in groundwater samples from MW-9 The District's laboratory reported non-detect for TPH-g in the third quarter 1994 ' sample from MW-9 However, the outside laboratory detected petroleum hydrocarbons at 24 micrograms per liter (µg/L) The Outside laboratory noted that some chromatographic peaks were observed in the gasoline range, but were not ' characteristic of gasoline Quantitation was based on the gasoline standard 94€:S Iasi Bay Municipal Utility € rtnct 4042960013idgti crw 5 Stockton servicc Center "third Quarter 1994