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r , <br /> Pombo Ranch Property <br /> First Quarter Groundwater Sampling Report January 2005 <br /> Page: 2 <br /> 1.79 to 2.34 feet lower than levels recorded in the October 20, 2004. Shallow <br /> groundwater flow was toward a northwest trending trough with northeast and southwest <br /> components and very flat gradients (N4E/004 and S55W/0.007). A very slight upward <br /> vertical gradient was observed at the well pair MW5 and MW 105. Wellhead elevations, <br /> depth to water measurements, and groundwater elevations are shown below. Groundwater <br /> elevations and flow directions are shown on figure 2. Cumulative groundwater elevations <br /> are shown on a hydrograph in figure 7. <br /> Groundwater Elevations 01/20/05 <br /> Well Collar Elevation DTW GW Elevation <br /> MW-1 53.47 11.61 41.86 <br /> MW-2 53.22 11.62 41.6 <br /> MW-3 55.02 12.42 42.6 <br /> MW-4 53.55 11.7 41.85 <br /> MW-5 53.46 11.79 41.67 <br /> MW-105 1 53.55 11.81 41.74 <br /> Gasoline petroleum and volatile aromatic hydrocarbons were detected at very low <br /> concentrations in wells MW4 and MW5 located at and immediate down gradient from the <br /> former underground storage tanks. Fuel oxygenates were detected at very low <br /> concentrations in wells MW4. Laboratory analyses are shown below and on Figures 3, 4, <br /> and 5. <br /> Laboratory Groundwater Sample Results 01/20/05 <br /> Sample I.D. Gasoline Benzene Toluene E-Benzene Xylenes Oxygenates Dissolved 02 <br /> MW-1 <0.05 <0.3 <0.3 <0.3 <0.6 ND 1.47 <br /> MW-2 <0.05 <0.3 <0.3 <0.3 <0.6 ND 2.21 <br /> MW-3 <0.05 <0.3 <0.3 <0.3 <0.6 ND 4.52 <br /> MW-4 0.79 2.4 <0.3 32 46 45 mtbe 0.78 <br /> MW-5 1.1 <0.3 <0.3 11 <0.6 ND 0.87 <br /> MW-105 <0.05 <0.3 <0.3 <0.3 <0.6 ND 1.83 <br /> ND=Non Detect NA-Not Analyzed <br /> Mg/L for gasoline&DO pg/L for BTEX,MTBE,and 8260 Oxygenated Compounds <br /> Dissolved oxygen measurements were collected as part of the groundwater monitoring to <br /> provide an estimate of the level of biologic activity in the groundwater. The dissolved <br /> oxygen was measured during this monitoring event in the field (and noted on the field <br /> logs), using a down hole meter. Dissolved oxygen concentrations are presented in the <br /> above table and in figure 6. <br /> i <br />