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Geofogica(Technics Inc. Page 2 Groundwater Monitoring Report Project No. 750.2 August 24,2000 The average groundwater elevation on July 14 was about 56.45 feet above MSL, which is approximately 61.65 feet below ground surface. A groundwater gradient was calculated for the event and groundwater was flowing N720W at 0.0024 ft/ft. Data is summarized in Table 1, Appendix A. Gradient directions are shown on Figure 3: Gradient Map. The three monitoring events for grouondwater gradient shows that the gradient slope and direction are similar. 1.2 Groundwater Sampling Procedure On July 14, 2000 Don Light of Del-Tech mobilized to the site to develop the monitoring wells and conduct a groundwater monitoring event. The wells were installed April, June and July of 1999 but were finished off below grade so that road and sidewalk construction could take place. In early April of 2000 the wells were relocated and finished to ground surface. Before development'was attempted, the wells were sounded for depth to water. Since the wells had never been developed after installation, Don Light first developed the wells by surging and pumping them until a clear stream of water was obtained. Once all of the wells had been developed, Mr. Light returned to the first well that had been developed and began &Wr%or the following sampling process: • The wells were purged of at least three well volumes of stagnant water using a dedicated 4.4 Waterra pump. Purging continued until the temperature, conductivity, and pH of the groundwater stabilized (<10% variation between three readings) indicating that formation 9.9 water representative of aquifer conditions was entering the well. These water duality parameters were measured at intervals of each well volume purged. • A stainless steel bailer was used to collect each sample. Care was taken to minimize 6.0 sample agitation from the initial filling of the bailer to the transfer of the sample to the VOA vials. • Once the sample containers were filled and capped, the bottles were inverted, tapped, and checked for headspace bubbles. Each sample container was identified and labeled with a unique designation, inserted into foam holders and placed in an ice chest cooled to 4°C for transport to the laboratory. La • All non-disposable sampling equipment was decontaminated using a steam cleaner before and between uses. Disposable gloves were used by the technician to collect all samples and were changed with each sampling event. A field blank (prepared from water provided by the laboratory poured into a VOA vial on site) accompanied the samples to the laboratory to serve as checks against cross V contamination. %.. 4 4