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i� Chevron Products Company Page 1 Former Chevron service station #9-5775, 301 West Kettlernan Lane, Lodi, California July 15, 2002 1.0 INTRODUCTION SECOR International Incorporated (SECOR), on behalf of Chevron Products Company (Chevron), presents second quarter 2002 (2Q02) groundwater monitoring and sampling results, and operating data for the groundwater extraction (GWE) and soil vapor extraction (SVE) systems at 301 West Kettleman Lane, Lodi, California (Figure 1). This report was prepared in accordance with Cleanup and Abatement Order (CAO) No. 5-00-704, dated April 20, 2000 (Attachment A), and covers the period of March 27, 2002 through June 25, 2002. 2.0 GROUNDWATER MONITORING AND SAMPLING Between April 29 and 30, 2002, SECOR conducted 2Q02 groundwater monitoring and sampling. Wells were gauged on April 29, 2002, and sampled on April 29 and April 30, 2002. Field and laboratory procedures are presented in Attachment B. Certified laboratory analytical reports and chain -of -custody documentation and monitoring and sampling field data sheets are included in Attachments C and D, respectively. A brief description is presented below. 2.2 Monitoring Well Gauge Data During the 2Q02, monitoring well gauge data indicates the approximate depth to groundwater r in A, B, and C -zones ranges from 57 to 59 feet below ground surface (bgs). Gauge data is presented as Table 1. Groundwater flows measured in the A -zone were calculated to flow to the southeast under an approximate gradient of 0.28 feet/foot (ft/ft). Groundwater near the site appears to flow radially toward extraction well EX -3 (Figure 2). Groundwater in the B - zone flows to the southeast, with an approximate hydraulic gradient of 0.01 ft/ft (Figure 3). 2.1 Sample Analytical Results During the 2Q02 event groundwater samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg), benzene, toluene, ethyl -benzene, and total xylenes (BTEX), methyl tertiary butyl ether (MtBE), tertiary butyl alcohol (TSA), di -isopropyl ether (RIPE), ethyl tertiary butyl ether (EtBE), tertiary amyl methyl ether (TAME), ethanol, methanol, ethylene di -bromide (EDB), and 1,2-dicholoethane (1,2 -DCA). Sample analytical results are presented as Table 2. Maximum concentrations of detected constituents for A, B, and C - zones are presented in the table below. An A -zone isoconcentration contour map for MtBE is presented as Figure 4. 1:IChevron1957751Periodic MonitoringlQuarterly Progress Reports1200212nd Quarter -2002 Progress Report.doe