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2-3 L. remaining annular space of each well was filled with neat cement on April 21 and 22, 1987 . Each well was completed at grade with a i' watertight utility box. The construction details for each well are in Appendix E. La Following installation, each well was developed using a stainless steel bailer to surge and bail the well until the water was relatively sediment free. Between 25 and 40 gallons (about 9 to LO 15 well casing volumes) of water was purged from each well. Each well was sampled on April 23 , 1987 , with a Teflon bailer equipped with a bottom-emptying valve. Prior to sampling, pH, L. specific conductance , and temperature of the discharged water were monitored, and bailing was continued until these parameters had stabilized (when three consecutive readings, taken 5 minutes apart, L, are within 10 percent of each other) . Approximately 20 additional gallons of water representing approximately 7 well casing volumes, were removed prior to sample collection. Each sample was then L' drained directly from the bottom valve into six 40-milliliter glass bottles with Teflon-lined septums and into 1/2-liter plastic bottle containing nitric acid preservative . The samples were stored on ice from the time of collection through delivery to BC' s Emeryville v laboratory. Pending results of the analytical tests, all groundwater produced during well development and sampling was contained and temporarily stored on site in 55-gallon drums. La All down hole drilling equipment was steam-cleaned prior to use at each borehole. All soil and groundwater sampling equipment was washed with laboratory detergent and tap water then rinsed with Le washed water prior to each use, as described in the Work Plan (Appendix B) . i. L. Lo La LO BROWN AND CALDWELL C CONSULTING EN&NEERS