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Ms Lori Duncan Page 2 of 3 Groundwater Sampling Due to the presence of free product in well MW3, groundwater samples were only collected from wells MW1, MW2 and MW4 A muimum of three well casing volumes of water was purged from each well using a bailer prior to sampling The physical parameters of temperature, pH and electrical conductivity were measured during the purging process All downhole equipment was decontaminated pnor to and between uses using a solution of laboratory-grade detergent, then double rinsing in separate containers of clean nese water Groundwater samples were collected using a dedicated, single-use, disposable bailer after the physical parameters had stabihzed and water levels recovered to their pre-purged levels The samples were placed into an ice chest cooled to approximately 4°C and transported to Argon Laboratories (ELAP 92359) under chain of custody protocol Well purge logs are included in Attachment A Free Product Measurement and Recovery A Ground Zero technician measured and removed free product from well MW3 on October 12, October 26, November 5, November 12, November 21, December 10, and December 12, 2001 The thickness of measured product averaged 0 77 feet during the reporting period Approximately 74 gallons of product/water mixture was removed from well MW3 by manually bailing the product from the well The bailed product was stored in a double-contained salvage drum Table 2 summarizes product thickness measurements and volume removed Field notes associated with product bailing are included in Attachment B GROUNDWATER ANALYTICAL RESULTS Groundwater samples were analyzed for TPHg and TPHd using EPA method 8015M, BTEX using EPA method 8020,VOCs, oxygenated gasoline additives, 1,2-chchloroethane (1,2-DCA), and ethylene dibromnde (EDB)using EPA method 8260B, TRPH using EPA Method 1664, and dissolved(filtered) lead using EPA Method 6010/200 7 No TPI-1g, TPHd, TRPH, BTEX, oxygenated gasoline additives, 1,2-DCA, EDB, or lead was detected in groundwater samples collected from wells MW1, MW2, or MW4 PCE was detected at concentrations of 23 parts per billion (ppb), 21 ppb, and 21 ppb, respectively, in wells MWl, MW2, and MW4 Chloroform was detected at 3 9 ppb, 3 0 ppb, and 3 9 ppb, respectively, in wells MW I, MW2, and MW4 Low levels of cis-l,2-dichloroethene(4 0 ppb) and trichloroethene(3 2 ppb)were also detected in well MW1 Only PCE was detected at levels exceeding the primary Maximum Contaminant Level (MCL) established by the State of California Department of Health Services The established MCL for PCE is 5 0 ppb Groundwater analytical results are summarized in Tables 3 and 4 Attachment C contains laboratory reports and chain of custody documentation SUMMARY Groundwater levels and the direction of groundwater flow beneath the site were generally consistent with ihistorical measurements An average of 0 77 feet of free product was measured in well MW3 during the UGZA FSISYSOiIData1GROLTNDZEIGABBARDIreports14QM2UUl doc.