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n+ t <br /> FIELD ACTIVITIES <br /> • Depth to Groundwater Measurements <br /> On September 2, 2003, representatives of Geocon measured the depth to groundwater in monitoring <br /> wells MW-9, MW-11 through MW-14, MW-16, MW-19, MW-20, MW-24, MW-25, VM-1 and VM-2 <br /> using a battery operated water level meter The measurements were obtained from surveyed reference <br /> points at the top of the well casing (TOC) The approximate well locations and site features are <br /> depicted on Figure 2, Groundwater Elevation Map - September 2003 <br /> During the Third Quarter - 2003, the depth to groundwater in the twelve existing wells was recorded <br /> between 52 06 and 52 97 feet below TOC Based on the September 2003 groundwater elevation data, <br /> the groundwater beneath the Site appears to be directed toward the northeast at an average gradient of <br /> 0 005, which is consistent with historical groundwater flow A review of the last reported groundwater <br /> level measurements for the Site indicates that from June 2003 to September 2003 the groundwater <br /> levels in each of the wells decreased an average of 1 36 feet A summary of the TOC elevations, depth <br /> to groundwater measurements and Mean Sea Level groundwater elevations is presented on Table 1 <br /> Well Purging and Sampling <br /> On September 2, 2003, approximately three well volumes of water (3 5 to 75 gallons) was extracted <br /> from each well utilizing a 2-inch diameter submersible pump or a disposable bailer During the well <br /> purging activities, the groundwater was monitored for pH, electrical conductivity, temperature, and <br /> turbidity This information is included on the Monitoring Well Sampling Data Sheets presented in <br /> Appendix B <br /> Following the purging activities, groundwater samples were collected from the wells and decanted into <br /> four 40-milliliter volatile organic analysis vials and one one-liter amber glass bottle The samples were <br /> sealed, labeled, placed in an ice chest containing ice, and subsequently transported to the laboratory <br /> using standard chain-of-custody protocol <br /> The extracted groundwater was placed into eleven Department of Transportation-approved, 17-H, 55- <br /> gallon drums and temporarily stored onsite pending receipt of laboratory analysis The drums will be <br /> transported by ABCO Environmental Services to an appropriate disposal facility in October 2003 <br /> ANALYTICAL METHODS AND RESULTS <br /> Laboratory Analyses <br /> Groundwater samples were delivered to Creek Environmental Laboratories, Inc , a Caltrans-approved <br /> and California-certified analytical laboratory, for the analyses of TPHg and TPHd following EPA Test <br /> Method 8015, benzene, toluene, ethylbenzene and total xylenes (BTEX) following EPA Test Method <br /> 8020 and fuel oxygenate compounds (FOCs) including MTBE, tert-amyl methyl ether (TAME), ethyl <br /> tert-butyl ether (ETBE), di-isopropyl ether (D1PE) and TBA following EPA Test Method 8260 <br /> Groundwater analytical results are summarized on Table 1 Laboratory reports and cham-of-custody <br /> documentation are presented in Appendix C <br /> Project No 5$475-06-24H -2- October 23,2003 <br />