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Cumulative FP Recovered to Date NA Depth to Groundwater(upper zone) 48 91 to 50 83 feet below top of well casing Depth to Groundwater(lower zone) 49 82 to 51 65 feet below top of well casing Groundwater Flow Direction/Gradient(upper zone) East/0 0006 ft/ft Groundwater Flow Direction/Gradient(lower zone) South-southeast 10 006 ft/ft DISCUSSION At the time of the fourth quarter monitoring event, groundwater was encountered in the monitoring wells screened within the upper zone (wells screened between 46 5 and 70 feet below ground surface (bgs)) at depths ranging from 48 91 to 50 83 feet bgs Well MW-3 was dry, well VEW-1 was obstructed, and well VEW-2 was inaccessible due to a rubbish pile Groundwater was encountered In the monitoring wells screened within the lower zone (wells screened between 94 and 115 feet bgs) at depths ranging from 49 82 to 51 65 feet bgs Groundwater elevations decreased approximately 0 16 to 0 30 feet in upper zone wells (except well MW-5, which increased 0 61 feet) since the August 27, 2002, monitoring event In the lower zone wells, groundwater elevations decreased 014 to 1 27 feet (except well MW-8, where groundwater rose 0 09 feet) The groundwater flow direction on December 5, 2002, was calculated to be eastward at a gradient of 0 0006 ft/ft in the upper zone Since 1995, groundwater flow in the upper zone has consistently been toward the east and southeast A groundwater contour elevation map for the upper zone is shown on Figure 2 The depth to water measured in well MW-5 during this quarter appeared anomalous, therefore the well was not used in generating the groundwater contour elevation map In the lower zone, groundwater flow during the fourth quarter 2002 was toward the south-southeast at an average gradient of 0 006 ft/ft Groundwater flow in the lower zone has historically been toward the south and east A groundwater contour elevation map for the lower zone is shown on Figure 3 V)weQ4 TPHG or benzene were not detected in the samples collected from upper zone wells MW-2 or MW-4 through MW-7 The sample from well MW-4 contained toluene (0 85 µg/L), xylenes (0 79 µg/L), and MTBE (0 62 pg/L) 1,2-DCA was detected in well MW-2 (29 pg/L) EDB was not detected In any of the upper zone wells In the lower zone wells, TPHG and BTEX were detected in well MW-9, TPHG and benzene were detected In well MW-8, and MTBE was detected In well MW-12 (0 76 Pg/L) The highest concentrations of TPHG (180,000 µg/L) and benzene (25,000 µg/L)were detected in well MW-9 1,2-DCA was detected in well MW-9 (780 pg/L), MW-11 (2 7 pg/L), and MW-12 (2 0 µg/L), and TBA (54 µg/L)was detected In well MW-8 EDB was not detected in any of the lower zone wells TPHG, benzene, and MTBE concentrations for samples collected and analyzed during the fourth quarter 2002 are included on Figure 4 PHS/EHD has requested that all peaks detected in the analyses be reported A copy of the laboratory tentatively identified compounds (TIC) report is attached Tentatively identified compounds were reported for wells MW-4, MW-8, and MW-9 Results of the TIC analysis are summarized in Table 3 • p\Apache Plastics\Quarterly reports\2002\Apache_4Q02 DOC 3TRATU5