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Mr. Harlin Knoll August 29,2001 <br /> 2nd Quarter 2001 QMR Project No.2007-0065-01 <br /> Page 3 <br /> SAMPLING, ANALYSIS, AND MONITORING PROGRAM RESULTS <br /> Groundwater samples were collected from 11 monitoring wells on May 22, 2001 and <br /> forwarded to Alpha Analytical, Inc. for analysis. Groundwater samples were analyzed <br /> for total petroleum hydrocarbons as gasoline (TPHG) using United States Environmental <br /> Protection Agency (USEPA) Method 8015B/DHS LUFT Manual, and for benzene, <br /> toluene, ethylbenzene, total xylenes (BTEX compounds), methyl tertiary butyl ether <br /> (MTBE), tertiary butyl alcohol (TBA), disopropyl ether (DIPE), tertiary amyl methyl <br /> ether (TAME), ethyl tertiary butyl ether (ETBE), and 1,2-dichloroethane (1,2-DCA) <br /> using USEPA Method 8260B. Certified Analytical Reports with chain-of-custody <br /> documentation are included in Appendix C. <br /> A summary of the groundwater analytical data is presented in Table 2 and Figure 3. <br /> Petroleum hydrocarbons and fuel oxygenates were not detected above laboratory <br /> reporting limits in the samples collected from monitoring wells MW-1, MW-2, MW-6, <br /> MW-7, MW-9, and MW-10, consistent with the previous sampling events. <br /> Concentrations of TPHG, benzene, and MTBE decreased in the samples collected from <br /> wells S-1, S-2, MW-4 and MW-8 since the previous sampling event. The highest TPHG <br /> concentration of 13 milligrams per liter(mg/L) was detected in the sample collected from <br /> monitoring well MW-3, while the highest MTBE concentration of 780 micrograms per <br /> liter (µg/L) was detected in the sample collected from monitoring well S-1. <br /> Concentrations of TPHG, BTEX, and MTBE detected at monitoring well MW-3 <br /> increased since the previous sampling event. <br /> VAPOR EXTRACTION WELL INSTALLATION <br /> Stratus installed a vapor extraction well to enhance performance of the SVE system <br /> operating onsite and its zone of influence. Stratus prepared and submitted a work plan to <br /> install a vapor extraction well and San Joaquin County PHS/EHD subsequently approved <br /> the work plan. Prior to implementation of field activities, a well construction permit was <br /> obtained from San Joaquin County PHS/EHD. Underground Service Alert (USA) and <br /> San Joaquin County PHS/EHD were subsequently notified 48 hours prior beginning work <br /> activities. <br /> Soil Borings <br /> A Stratus geologist oversaw Western Strata Exploration Inc., a California licensed <br /> drilling company (C57 ## 552198), complete work activities on May 2, 2001. Drilling <br /> was completed using 10-inch diameter hollow stem augers. Soils were classified on-site <br /> using the Unified Soil Classification System (USCS). All work was performed under the <br /> direction of a California Registered Geologist. The boring log detailing soil lithologies <br /> CA1Project FilesWSA Gaso1ine100651Qtr1yNUSA 0065 2Q01 Report.doc 5rRAW5 <br />