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First Quarter 2005 Quarterly Groundwater Monitoring Report Stockton Center Site Authority—University Park March 2,2005 Page 2 of 6 Table 1 Summary of February 2005 Quarterly Groundwater Monitoring Results Field Activit Number of groundwater monitor wells 3 Number of monitor wells-sampled 3 Monitor wells measured for water level 3 Date(s)monitored 2103 &2104105 Site Hydrology Approximate average depth to Average increase(+)/decrease(—)in groundwater 41.70 depths to groundwater since last -1.06 (November 2004)monitoring A22roximate flow direction East Groundwater Contamination Wells containing free product None Wells with odor noted MW-2&MW-3 Number of monitor wells with all of Number of monitor wells with any of benzene, 1,2-DCA, and MTBE 1 benzene, 1,2-DCA, and/or MTBE 2 concentrations below the MCLS concentrations at or above the MCLS Nature of contamination: Benzene Range of analyte concentrations detected in the wells: Ethyl Benzene (pg/L): <0.5 -7.1 benzene Ethyl benzene(pg/L): <0.5 -5.0 Total Total Xylenes(pg/L): <1.0 -4.4 Xylenes MTBE(pg/L): <0.5 - 89 MTBE 1,2-DCA(pg/L): <0.5 - 120 1,2-DCA TAME(pg/L): <0.5 - 1.5 TAME TBA(pg/L): <5.0-26 TBA TPH-G(ug/L): <50-690 TPH-G TPH-D(pg/L,): <50- 180 TPH-D Additional Information BTEX were analyzed by EPA Method 8020. Gasoline oxygenates were analyzed by EPA Method 8260E Total petroleum hydrocarbons were analyzed by EPA Method 8015M. All wells were purged prior to sam lin . FIELD OBSERVATIONS On February 3 2005, a Condor representative was on site to make field observations at the three monitor wells, MW-1, MW-2, and MW-3, as part of the first quarter 2005 quarterly groundwater monitoring event. Field observations included appearance of samples (color, clarity, and presence of petroleum product sheen or phase in samples), collection of water quality field parameters, and water level measurement. No separate phase petroleum or sheen was noted in the groundwater recovered from the wells. Field inspection samples collected from monitor wells MW-2 and MW-3 were noted as having slight and moderate petroleum hydrocarbon odor, respectively. Field observations are included in the groundwater monitoring field forms, attached. GROUNDWATER ELEVATIONS AND GRADIENT On February 3, 2005, the depth to groundwater was measured in monitor wells MW-1, MW-2, and MW-3, Groundwater elevation data is presented in Table 2, on the following page. The average depth to groundwater in the monitor wells was 41.70 feet below the surveyed well collar measuring points (the measuring points are slightly below the ground surface). The average groundwater elevation measured i the monitoring wells increased 1.06 feet between November 10, 2004, and February 3, 2005. The'% 4M k IL a CONDOR