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f t Second Quarter 2005 Quarterly Groundwater Monitoring Report Stockton Center Site Authority—University Park June 13,2005 Page 2 of 6 Table 1 Summary of May 2005 Quarterly Groundwater Monitoring Results Field Activit Number of groundwater monitor wells 3 Number of monitor wells sam led 3 Monitor wells measured for water level 3 Date s) monitored 512105 Site Hydrology Average increase(+)/decrease(--) in Average depth to groundwater 40.09 depths to groundwater since last -1.62 Februa 2005 monitoring Approximate flow direction North Groundwater Contamination Wells containing free product None Wells with odor noted 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 Ethyl Range of analyte concentrations detected in the wells: benzene Benzene(�LgIL): <0.5— 10.2 Total Ethyl benzene(µg/Q: <0.5—24.7 Xylenes Total Xylenes (µglL): < 1.0— 12.7 MTBE MTBE(µglL): <0.5--30.8 1,2-DCA 1,2-DCA(�ig/L): <0.5—29.2 TBA TPH-G(pg/L): <50-557 TPH-G TPH-D(µg/L): <50- 144 TPH-D Additional Information BTEX were analyzed by EPA Method 8020. Gasoline oxygenates were analyzed by EPA Method 8260B Total petroleum hydrocarbons were analyzed by EPA Method 8015M. All wells were purged prior to sam lin . FIELD OBSERVATIONS On May 2, 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 second 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. The field inspection sample collected from monitor well MW-3 was noted as having a strong sulfur odor. Field observations are included in the groundwater monitoring field forms, attached. GROUNDWATER ELEVATIONS AND GRADIENT On May 2, 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 40.09 feet below the surveyed well collar measuring points (the measuring points are slightly below the ground surface). The average groundwater elevation measured in Ca CONDOR