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I s Ground Zero personnel- described and logged the borings according to the Unified Soil Classification System (USCS). Descriptions of the soils encountered in the borings are presented in the Logs of Borings, Appendix A. Groundwater Monitoring Well_Construction Monitoring well MW 1 was completed using flush threaded, 2" diameter PVC well screen and casing. The well was screened from 42.5 ft to 62.5 ft below ground surface. The screened portion of the well consists of 0.020-inch wide, machine-slatted PVC casing. The casing from the top of the screened portion to one foot below ground surface is PVC blank. I The annular space of the well was filled with silica sand from the.total depth of the well to approximately 2 feet above the screened casing. A bentonite seal was placed above the sand pack for a total thickness of 2 feet (3 8.5 to 40.5 feet below ground surface). A neat cement slurry was placed above the bentonite seal to 1 foot below ground surface. The top of the casing was covered with_a locking cap and padlock, and the bottom has a threaded end-cap. The well head was protected with a cast-iron well head box installed approximately 112-inch above the surrounding ground to prevent water from ponding over the well-head cover. The well-head cover has a locking, watertight, expanding seal to protect the well against surface-water infiltration. Groundwater Monitoring Well Development and Sampling On May 24, 1995 a Ground Zero technician measured depth to groundwater in monitoring well MW l and then surged and developed the groundwater monitoring well using a bailer and submersible pump. Approximately 7.7 well casing volumes of water were extracted from the well prior to sampling. pH, EC, and Conductivity measurements were taken, and had stabilized prior to sampling. The well was also allowed to recharge to approximately 99% before the groundwater samples were collected. The purged water was stored onsite in a labeled DOT 55- gallon drum prior to disposal. Field data sheets are included in Appendix B. The samples were shipped to Argon Laboratories under Chain-of-Custody protocol for analysis of TPHg by EPA Modified Method 8015, BTEX by EPA Method 8020, Total Oil and Grease by Method 418.1, and Total Lead by Method 7421. Laboratory Reports, Chain-of-Custody Records, and Quality Assurance/Quality Control Documentation are included in Appendix C. e I