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I Third Quarter,2002 Quarterly Groundwater Monitoring Report Eckert Cold Storage,Manteca,California November 19,2002 Page 3 groundwater gradient was 0.0013 ft./ft. towards the northwest, as shown. Groundwater elevation data for September 30, 2002 are presented in Table 1,below. Table 1 —Groundwater Elevation Data(September 30, 2002) Monitoring Screened Interval(bgs) TOC Elevation Depth To Water Groundwater Well Elevation MW-1 13 -28 38.09 20.39 17.70 MW-2 15 -30 37.90 20.18 17.72 MW-3 15 -30 38.31 20.60 17.71 MW-4 12-27 37.84 20.32 17.52 MW-5 14-34 41.22 23.51 17.71 MW-6 13 -33 37.65 19.94 17.71 MW-7 13 -33 38.22 20.46 17.76 MW-8 17-37 37.76 20.18 17.58 t TOC Elevation: Elevations are measured from the top of the well casing and are referenced to NGS Benchmark HS4486,elevation 35.03 feet using NAVD 88 datum. All measurements are in feet. LABORATORY ANALYTICAL RESULTS The groundwater samples collected from monitor wells MW-1 and MW-3 through MW-8, and domestic well DW-1 were analyzed for BTEX, TPH-G, and selected gasoline oxygenates/additives including MTBE by Argon Laboratories of Ceres, California. MW-2 was not sampled as damage to the well casing during installation of the well prevents placement of bailers and pumps down the well. • The current laboratory analytical results, shown in Table 2, on the following page, are generally consistent with historical laboratory analytical results. Historical groundwater monitoring data is included in Attachment C. Laboratory certificates of analyses and the chain-of-custody for the samples are included in Attachment D. Quarterly sampling of Total Petroleum Hydrocarbons quantified as Diesel (TPH-D) was discontinued for the third quarter 2002. In a letter to Mr. Harlin Knoll of the SJCEHD, dated September 26, 2002, Condor documented approval by the SJCEHD to discontinue TPH-D as a quarterly monitored analyte. SJCEHD approval was based on historical data indicating that the presence of TPH-D in site groundwater has been sporadic, very low in concentration, and likely the result of weathered gasoline rather than from the potential presence of diesel in the source area. i CONDOR