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r <br /> I <br /> MW-1 is screened between 6-feet bgs and 18-feet bgs Monitoring wells <br /> MW-2 and MW-3 are screened between 45-feet bgs and 165-feet bgs <br /> Monitoring wells MW-4 and MW-5 are screened between 4-feet bgs a n d <br /> 16 5-feet bgs In each monitoring well, Lonestar #2112 Monterey sand <br /> occupies the annular space between the borehole and the casing from t h e <br /> bottom of the boring to approximately 1-foot above the screen A 1 -foot <br /> thick hydrated bentonite layer separates the sand from the overlying <br /> cement surface seal The cement surface seal in these shallow wells was <br /> placed by gravity free-fall <br /> The wellheads of all five wells are secured with locking wellplugs beneath <br /> at-grade traffic-rated vaults <br /> 9.2 MonitorinlZ Well Developmen <br /> Monitoring wells MW-1 through MW-5 were developed on October 9 , <br /> 2000, using surge block agitation and submersible pump evacuation In <br /> total, at least ten times the volume of the well casing in was removed <br /> during the development process Upon completion of the well <br /> development, the water produced in all five wells was clear <br /> 9.3 Monitoring WellSing <br /> On October 12, 2000, ASE associate geologist Ian Reed collected <br /> groundwater samples from each monitoring well for analysis Prior t o <br /> sampling, the wells were purged of four well casing volumes of <br /> groundwater using dedicated bailers The pH, temperature a n d <br /> conductivity of the purge water were monitored during evacuation, and <br /> samples were not collected until these parameters stabilized Samples <br /> were collected from the wells using pre-cleaned dedicated polyethylene <br /> bailers All groundwater samples were decanted from the bailers into 40- <br /> ml volatile organic analysis (VOA) vials, preserved with hydrochloric acid <br /> and sealed without headspace All of the samples were labeled and stored <br /> on ice for transport to Kiff Analytical, LLC under chain of custody See <br /> Appendix F for a copy of the Field Logs <br /> 9.4— _ Purge Water Disposal <br /> Well development and sampling purge water were contained in 55-gallon <br /> steel drums and left on-site for temporary storage This water will b e <br /> transported to an appropriate facility for recycling <br /> 574 West Grant Line Road Report — October 2000 <br /> -8- <br />