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' Third Quarter 2004 Groundwater Report 8200 N Highway 99, Stockton, CA Page 5 of 6 ' maps of TPHg, benzene, and MTBE in the A Zone, respectively, from the September 2004 data The figures include analytical results of groundwater samples collected from the newly installed well EW2, which was discussed in Section 3 0 of this report Attachment H contains laboratory ' reports and chain-of-custody documentation for groundwater samples collected from wells MW2 through MW16 and EW2 in September 2004 Attachment I contains graphs of TPHg, benzene, and MTBE concentrations of over time in all site wells ' 4.3 Domestic Well Sampling and Analysis ' At the direction of EHD in a letter dated October 10, 2003, Ground Zero collected water samples from eight nearby domestic wells, including the site facility well The samples were collected from either a sample port at the wellhead or from the nearest available sampling location (i a garden ' hose) Samples were collected after the pump was turned on for approximately 15 minutes The samples were immediately stored in an ice chest refrigerated to a temperature of approximately 4°C and delivered under chain of custody protocol to FGL Laboratories(FLAP #1563) and analyzed for ' volatile organic constituents utilizing EPA Method 524 2 No VOCs were detected in any of the samples collected from the nearby domestic wells Copies of ' the laboratory reports were submitted to the respective property owner The laboratory reports for samples collected from the nearby domestic wells are included in Attachment J Figure 7 shows the locations of the domestic wells relative to the site 5.0 SUMMARY ' The groundwater treatment system was put into operation on November 5, 2003 pursuant to WDR General Order No R5-2003-004412 The system generally operated continuously during July, ' however due malfunctions in the flow meter the system was down for most of August, and the system generally operated continuously through most of September until the extraction well pump failed on September 23, 2004 When in operation during the reporting period, the average flow rate ' through the treatment system was approximately 12 gallons per minute (gpm) Approximately 40,636 gallons of water was treated during the reporting period A total of approximately 366,498 gallons of groundwater has been treated between November 2003 and September 24, 2004 During ' that period, approximately 67 pounds of petroleum hydrocarbons, including approximately 22 pounds of MTBE, were removed through the treatment system ' Groundwater in the shallow aquifer beneath the site generally flowed to the northeast when monitored on September 14, 2004, although a pumping depression was evident around the ' extraction well (MW 1) MTBE was detected in downgradient A Zone well MW12 on September 16, 2004, unlike last reporting period (June 24, 2004) where it was not detected No MTBE was detected in wells MW 10 or MW 11, located west of well MW 12, or in wells MW 15 and MW 16, which are located downgradient of well MW12 ' G IGROUNDZEITULEBURGIRepo,"IQMR12004131IM2"doc