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� 1 p This quarter's measurements of groundwater elevations were contoured and indicate a { delineated line between MW-1 and MW4 The area above the delineation line defined . ' directional flow in a north-northeasterly orientation while the area below the delineation line defined directional flow in a southeasterly orientation The hydraulic gradient averages 0 0014 � r feet per foot across the well field(above the delineation line)and 0 0020 feet per foot across the well field (below the delineation line) A groundwater elevation summary and directional flow map for the first quarter groundwater measurements are shown on Figure 4 I "r The groundwater elevation data collected during this event is typical of the site, and is consistent with historical data and seasonal trends 5.2 Groundwater Sample Analysis This section presents the results of the most recent(03110104)groundwater sampling event, and ' synthesizes these data with other data previously collected Table 2 WvI1 summarize the groundwater monitoring well analytical results from the most recent groundwater monitoring event Certified analytical laboratory reports and chain-of-custody documentation are included as Appendix C MTBE appeared for the �K-t time in MW-1 at a concentration of 3 1 ppb and TPH-diesel ' reappeared at a concentration of 3750 ppb All other constituents were below the reporting limits k MW-2 found continued contamination from TPH-diesel, TPH-motor oils, TBA and MTBE I DIPE reappeared at a concentration of 7 45 ppb BTEX and TPH-gasoline were below the detection limits MW-3 continues to remain free of contamination i TPH-diesel and TPH- motor oils in MW-4 remain below the detection limits, while BTEX and ' I TPH-gasoline remain consistent in their contamination levels MTBE made its first appearance f All groundwater samples secured by EI were logged in a cham-of-custody form, placed in an ice chest and picked up by a California Department of Health Services (DHS) certified laboratory for analysis ' 5.3 Free Product r r A September 1998 sample of groundwater monitoring well MW-2 found black, floating oil that ' appeared to be typical of used motor oil Floating oil has been removed from MW-2, using disposable bailers and absorbent socks, periodically since that time Approximately 19 8 gallons of floating oil have been removed(Table 3) f ' s Free product removal on 02/13/04 and 03/10/04 showed minimal amounts of oil(<1 TBSP) E 1 103 I