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l constructed in the 3rd aquifer between 110 and 120 feet and in the 15' aquifer between 57 and 67 feet GT-14 reached a depth of 120 feet and monitoring wells were constructed in the 3rd and 2nd aquifers (105-115 feet and 80-90 feet) GT-15 was terminated at 125 feet and wells were installed in the 3`d and 2nd aquifers at depths of 115-125 feet and 80-90 feet The shallower aquifer well in each boring was designated the A zone, and the lower aquifer was designated the B zone Twenty samples were analyzed for TPH-diesel, TPH-gasoline and benzene-toluene-ethylbenzene- xylene (BTEX) The laboratory report is in Appendix B and the data are summarized in Table 1 2 2 Groundwater Monitoring Groundwater monitoring took place on November 9 The wells were opened and allowed to equalize with atmospheric pressure, and then the depth to groundwater was measured with a water level meter In nested wells, the depth was measured in both casings The measurements were recorded on the Well Monitor Report (Appendix C) before the wells were purged Depth data are given in Table 2 A Grundfos purge pump was used to pump between 20 and 45 gallons of water from each of the newly constructed wells to remove sediment and tighten the sand pack Well GT-13A was not purged, because the screened interval in this well is 57-67 feet in the I" Riverbank aquifer and the water depth in this aquifer was approximately 69 feet at the time of sampling The older monitor wells were hand-bailed of approximately 6 gallons of water except for GT-5, which dried up after 2-3 gallons had been bailed The water was disposed of on site Samples were collected in disposable plastic bailers Diesel samples were preserved in 1-liter amber bottles, and gasoline samples were preserved in 40-m1 vials The Gillies domestic well (G-1) was also sampled (tlus well is scheduled for destruction in the near future), The samples were labeled and placed into a cooled ice chest for later shipment to the laboratory The laboratory report is contained in Appendix D and the data are summarized in Table 3 After the wells were-sampled, they were surveyed with a bwlder's level to determine the elevation of the top of the casing All wells except GT-10 (dry) were surveyed GT-5 was used as the relative base level benchmark Casing elevations are shown in Table 2 Also, all well locations were re- measured and minor adjustments were made to the site location map 3 0 RESULTS 3 l Lithology and Stratigraphy After six CPT borings were drilled in late 2003, four cross sections were constructed to identify and correlate stratigraphic units across the site The sections were presented in the Fourth Quarter 2003 Report Three of these sections have been revised and expanded using the data from wells GT-12 through GT-15 (Figures 3-5) The new data confirm the previous interpretation and little modification of the earlier sections is required • 3