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1 9 Forty feet of 0 020-inch slotted screen were placed in each well at approximate depths of 34 to 74 feet BGS The upper 20 feet of screen, above the current groundwater table depth of about 55 feet BGS, allows for future groundwater nses The bottom 20 feet of ' screen, below the groundwater table, allows for potential groundwater drawdown should pumping be used as an eventual remediation method ' Well annular spaces were filled using number 2112 sand as a filter pack along the screen, bentonite seal above the filter pack, and a cement/bentonite-mix grout to the surface ' Well construction diagrams, showing the depth and thickness of well materials, are contained in Appendix A Construction details are summarized in Table 1 Monitoring well ' construction procedures are more fully described in Appendix B ' 2.4 Equipment and Materials Decontamination ' All drilling, sampling, and monitoring well PVC material were decontaminated in accordance with USEPA guidelines Decontamination procedures are described in Appendix B ' 2.5 Well Development and Groundwater Sampling ' Each well was developed to consolidate the sand pack, allow solids-free water entry ' through the screen, and maximize groundwater yield Developed groundwater was stored and sealed in 55-gallon drums pending proper disposal Well development procedures are ' more fully described in Appendix B Groundwater samples were collected from 11 of the site wells in accordance with ' sampling procedures described in Appendix B Samples were not collected from wells MW-5 and MW-7 because they were dry Groundwater sampling records are included in ' Appendix C Prior to sampling, the water level and the presence of phase-separated hydrocarbon product (PSH) was measured in each well using an oil/water indicator There was no PSH measured in any well A very slight hydrocarbon sheen was observed on the groundwater 04/94/121382/125997/STOCKREP REP/1 1