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Third Quarter 2005 Quarterly Groundwater Monitoring Report Stockton Center Site Authority—University Park October 18,2005 Page 2 of 6 Table 1 Summary of September 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 09/01/05 Site Hydrology Average increase(+)/decrease(—)in -0.36 foot Average depth to groundwater 39.73 feet depths to groundwater since last (shallower) (May 2005)monitoring Approximate flow direction Northeast Groundwater Contamination Wells containing free product None Well(s)with odor noted MW-1,MW-2 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(�tg/L): <0.5—31.6 benzene Ethyl benzene(µg/L): <0.5—26.1 Total Total Xylenes(pgfl: < 1.0—22.4 Xylenes MTBE(µg/L): <0.5—51.3 MTBE 1,2-DCA(pg/L): <0.5—41.8 1,2-DCA TBA(µg/L): 5.0— 15.3 TBA TPH-G(pg/L): <50—699 TPH-G TPH-K(gglL):<250—333 TPH-K TPH-MO(pg/L): <500—724 TPH-MO TAME(µg/l-): <0.5— 1.0 TAME 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 sa lin . FIELD OBSERVATIONS On September 1, 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 third 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 samples collected from monitor wells MW-1 and MW-2 were noted as having strong and slight hydrocarbon odors, respectively. Field observations are included in the groundwater monitoring field forms, attached. GROUNDWATER ELEVATIONS AND GRADIENT On September 1, 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 1 `3 CONDOR