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Fourth Quarter 2004 Quarterly Groundwater Monitoring Report Stockton Center Site Authority—University Park January 10,2005 Page 2 of 6 Table 1 Summary of November 2004 Quarterly Groundwater Monitoring Results Field Activit Number of groundwater moEwater r wells 3 Number of monitor wells sampled 3 Monitor wells measured for level 3 Date(s)monitored 11/10&11/11/04 Site Hydrology Approximate average depth to Average increase(+)/decrease H in groundwater 42,76 depths to groundwater since last +1.36 feet (August 2004 monitoring Ap2roximate flow direction Southeast Groundwater Contamination Wells containing free product None Wells with odor noted MW-2 and 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 - 6.2 benzene Ethyl benzene(pg/L): <0.5 -2.5 Total Total Xylenes(pg/L): <1.0 - 1.9 Xylenes MTBE(µg/Q: <0.5 - 83 MTBE 1,2-DCA(}ig/L): <0.5 - 160 1,2-DCA TAME(pg/L): <0.5 - 1.4 TAME TBA(µg/L): <5.0-33 TBA TPH-G (µg/L): <50-510 TPH-G TPH-D (pg/L): <50- 130 TPH-D TPH-K(pg/L): <250-320 TPH-K Additional Information Volatile organic compounds were analyzed by EPA Method 8020. Total petroleum hydrocarbons were analyzed by EPA Method 8015M. All wells were Eured prior to sam lin FIELD OBSERVATIONS On November 10, 2004, 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 fourth quarter 2004 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 moderate and strong petroleum hydrocarbon odor, respectively. Field observations are included in the groundwater monitoring field forms, attached. GROUNDWATER ELEVATIONS AND GRADIENT On November 10, 2004, 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 42.76 feet below the surveyed well collar measuring points (the �1� CONDOR