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removed from MW3-3 during development At wells MW3-1 and MW3-2,very fine sand continued to enter the well casing throughout development and the pump could not be installed (required a sand content less than 5 mg/1) However, a total of about 70 gallons (about 17 well volumes)was ' bailed from both MW3-1 and MW3-2 and physical parameters remained stable after about 40 gallons were removed, indicating good communication with the aquifer ' 3.3 SAMPLING OF MONITORING WELLS Groundwater samples were collected on July 7, 1999 by PET and documented by Philip P Ross, ' R G Upon arrival at the site, water levels on all wells were obtained with an electronic sounder Prior to sampling each well, the presence of free-floating PHC product was assessed using a clear ' polyethylene bailer No floating product was observed in any of the wells The wells were then purged of at least three casing volumes using an electric submersible pump The purge pump was decontaminated before arriving at the site and between each well Periodic field measurements of temperature, pH, and specific electrical conductance were made on the purge water from each well, and samples were collected when these parameters reached relatively constant values A new, disposable polyethylene bailer was used to collect the water samples for laboratory chemical ' analysis Groundwater samples were preserved and transported under chain-of-custody procedures to PET's laboratory for analysis of BTEX and methyl tertiary butyl ether(MTBE)using EPA Method 8020, and TPHg using EPA Method 8015m In addition, all samples were analyzed for the following ' oxygenated compounds using EPA Method 8260,MTBE,tertiary butyl alcohol(TBA),di-isopropyl ether(RIPE), ethyl tertiary butyl ether(ETBE), and tertiary amyl methyl ether(TAME) A travel blank was prepared in the field from distilled water Laboratory analytical reports and chains of ' custody are included in Appendix B ' 3.4 MONITORING WELL ELEVATION SURVEY The elevation of each of the monitoring wells was surveyed by Dillon and Murphy Engineering of ' Lodi, California A map showing the location and elevation of the wells is presented in Appendix A 3.5 SUPPLY WELL SURVEY As requested by the PHS/EHD, a survey of domestic, municipal, agricultural, industrial, and other supply wells within a 2,000-foot radius of the site was conducted The survey included a review of records on file with the Department of Water Resources, California Water Service (the local i ' vipn 6 PHILIP P. Ross, R.G.