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5` A Apache Plastics 1Q 2002 QMR Page 3 elevations in the monitoring wells were generally unchanged since the previous monitoring event (February 2002) Figure 2 presents groundwater elevation contours (corrected to mean sea level [msl]) for monitoring wells with total depths of less than 75 feet bgs (shallow wells) Figure 3 shows groundwater elevation contours for wells with total depths ranging from 105 to 115 feet bgs (deep wells) At the time of the second quarter 2002 monitoring event, groundwater was encountered in the monitoring wells at depths ranging from 46 56 to 55 80 feet bgs The groundwater flow direction in the upper water bearing zone was calculated to be towards the southeast at an average gradient of 0 01 ft/ft The groundwater flow direction in the lower water bearing zone was calculated to be towards the east at an average gradient of 0 043 ft/ft East and southeast groundwater flow directions are generally consistent with previous groundwater monitoring events SAMPLING, ANALYSIS, AND MONITORING PROGRAM RESULTS Groundwater samples were collected from twelve groundwater monitoring wells on May 20, 2002 and submitted to Alpha Analytical, Inc in Sparks, Nevada, a California state certified analytical laboratory, for chemical analysis Strict chain-of-custody procedures were followed from the time the samples were collected to the time the samples were delivered to the laboratory The samples were analyzed for total petroleum hydrocarbons as gasoline (TPHG) using USEPA Method SW8015B DHS LUFT Manual, and for benzene, toluene, ethylbenzene, and total xylenes (BTEX), methyl tertiary butyl ether (MTBE), tertiary amyl . methyl ether (TAME), tertiary butyl alcohol (TBA), di-isopropyl ether (DIPE), ethyl tertiary butyl ether (ETBE), and 1,2-dicloroethane (1,2-DCA) using USEPA Method SW8260B Sampling and analysis procedures are presented in Appendix B and certified analytical reports with chain-of-custody records are included in Appendix C Historic and second quarter 2002 groundwater analytical data are summarized in Table 1 and Table 2 Concentrations of TPHG, benzene, and 1,2-DCA in groundwater are also illustrated on Figure 4 The highest concentrations of TPHG (160 mg/1), benzene (20,000 µg/l), toluene (35,000 �tg/l), and 1,2-DCA (1,200 µg11), were detected in the sample collected from well MW-9, and the highest concentrations of ethylbenzene (3,900 µg/l) and xylenes (24,500 µg11) were detected in the sample collected from well VEW-2 TBA was detected in the samples collected from wells MW-2 (54 µg/1), MW-6 (9 5 µg11), and MW-8 (40 µg/1), and MTBE (4 3 µg/1)was detected in the sample collected from well MW-5 MTBE or other fuel oxygenates were not detected in any of the other samples STATEMENT OF LIMITATIONS The services described in this report were performed consistent with generally accepted professional consulting principals and practices No other warranty, expressed or implied, is made These services were performed consistent with our agreement with our client This report is solely for the use of our client unless otherwise noted Any reliance on this report by a third party is at such party's sole risk P\Apache Plastics\Quarterly reports120021Apache_2Q02 doe