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�` - y •'�; ,tom is .��` S:.f N.a - �, &k r removed from MW-1 during development. The remaining monitor wells were all developed by removing approximately 55-gallons of water from each well. As previously stated, soil borings SB-1 through -5 were all drilled to z 17.5 feet below ground surface. These borings were backfilled with the aforementioned cement grout mixture from total depth to ground surface. All grouting operations were witnessed by a SJLHD site inspector. Groundwater Sam lin Groundwater samples were collected for TPH-G and VOA analysis by Modified EPA Method 8015 and EPA Method 602, respectively, from each monitor well. Monitor wells Mod-1, -3, and -6, which showed the presence of elevated concentrations of VOAs, were also sampled for ethylene dibromide (EPA Method 504) and organic lead (tetraethyl lead). The primary supply well and the backup supply well at the site were sampled for VOCs (EPA Methods 601 and 602), ethylene dibromide (EDB) and total volatile hydrocarbons Q (Modified EPA Method 8015). TA Monitor wells were allowed to equilibrate following construction for a �' period of not less than 12 hours prior to groundwater sampling. Prior to sampling, the top-of-casing elevation for each well was surveyed relative to an assumed datum of 20 feet mean sea level (MSL), as derived from the United States Geological Survey topographic map of the Lodi North Quadrangle, California and depth to water measurements were taken to determine groundwater elevations at each well. Before sampling, monitor wells MW-1 through -8 were purged by pumping approximately 55 gallons of water from each well. Monitor wells MW-9 and -10 were bailed dry and allowed to recharge for approximately 5 to 10 minutes prior to collecting groundwater samples. Groundwater samples were collected from each monitor well with disposable, polyethylene, non-reactive bailers. Samples were collected at the supply wells from steel sampling ports after purging each well for approximately 15 minutes. Water samples were tranferred to appropriate sample containers by filling from the bottom to top of the container to minimize sample aeration. Each sample container was individually labeled and placed on ice in a thermally insulated chest. All water samples were delivered to the appropriate analytical laboratory with an accompanying chain-of-custody form. A al tical Services Analyses for TPH and VOAs in soil and groundwater samples were performed by Weston Analytical Laboratory of Stockton, California. Weston also conducted EDB analyses of groundwater samples taken from monitor wells MW- 1, -3, -6, and the primary supply well. McLaren Analytical Laboratory of Rancho Cordova, California performed the analyses of water samples taken from the back-up supply well for VOCs, EDB, and total volatile hydrocarbons-and-analyzed additional water-samples from the ma supply - y well for total volatile hydrocarbons. prim ry Pp 12