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N• a KLEINFELDER All three monitoring wells will be developed after installation. Each well will first sampled with a clear acrylic bailer to visually inspect the sample for a product layer or sheen. If no product layer or sheen is observed on the water samples, the wells will Le developed with a surge-block, air-lift tool,and/or bailer. Surging along the screened interval of the well will draw the sediment from the formation into and out of the well and set the sand pack. The sediment-Iaden water will be air-lifted from the well at a rate of approximately 0.50 gallons per minute (gpm). Each well will be developed until the discharge water runs relatively clear of fines. Approximately 5 to 10 well volumes will be removed from each monitoring wed. After the wells have been developed,the aquifer will be allowed to equilibrate. The wells will then be purged and sampled. During purging, field parameters (pH, conductivity, temperature)will be monitored. Samples will be collected after the field parameters have: stabilized (normally requiring the removal of 3 to 5 weIl volumes). After collecting a sample, the sample bottles will be immediately sealed, labeled, and placed in an iced cooler. At the end of the field day, the water samples will be delivered under chain-of- custody hain-ofcustody to California Analytical Laboratories/Enseco in West Sara jento. To minimize cross-contamination, developing and sampling equipment will be <<eam _- cleaned prior to use in each monitoring well. Water generated during well deve',tping and purging will be contained in 55-gallon drums and stored on site pending results of water analyses. 3.5 MONITORING WELL ELEVATION SURVEY A ground water flow direction will be estimated from the three monitoring wells. The relative elevations of the top of the 2-inch PVC casings will be surveyed for the three wells. The casing elevations will be tied into an assumed elevation, or a nearby county or USGS benchmark. Depth to the static ground water table will be measured for the top of each PVC using. The depth to water will then be subtracted from the elevation of the top of -. the well casing to provide a water table elevation for each monitoring well location. The ground water flaw direction,will be estimated from the measured water table elevations. 148-88-2109 6 ti