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between the augers and the screened portion of the well was backfilled with Lonestar #2-12 sand. As the filter pack was placed, the augers were withdrawn from the borehole so the sand flowed from the augers into the annular space of the borehole. The filter pack was extended to approximately two feet above the top of the screened portion of the casing. A two foot seal of bentonite clay was placed in the annular space above the filter pack. Since the bentonite seal was positioned above the water table, five gallons of potable water was added to allow the bentonite to swell. The remaining annular space was backfilled to the surface with sand/cement slurry ' Each monitor well was finished with a Universal water-tight monitoring well manhole set into concrete. A watertight, locking cap sealed the well casing inside the manhole Boring logs/well ' details are contained in Appendix II. ' 3.1.3 Groundwater Sampling On November 6, 1990, the monitoring wells were monitored in accordance with RESNA's Groundwater Monitoring Protocol (Appendix III) The wells were then purged in accordance with RESNA's Well Development Protocol (Appendix III) Water samples were then collected from the wells in accordance with RESNA's Groundwater Sampling Protocol (Appendix III) Applied Analytical analyzed the samples for BTEX and TPHG utilizing EPA 8020 and 8015 Imethodologies, respectively Groundwater analytical results are summarized in Table 3 1 3.2 Phase 2 Activities On October 28, 1991, RESNA personnel advanced three soil borings (MW4, MW5, MW6) to depths ranging from 27 to 30 feet below grade at the project site to accomplish the following 1) further define the lateral and vertical extent of petroleum hydrocarbon soil contamination, 2) further determine and define soil stratigraphy, and 3) install groundwater monitoring wells within the uppermost aquifer in order to assess groundwater quality The boring/well locations are plotted on Figure 2 GPR1227 JPL 4