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The groundwater samples, from each well, were collected in four, ;«`rs laboratory certified 40 ml, pre-cleaned glass VOAS, with Teflon j =' septa and labelled. The 40 ml glass VOAS were stored and transported in a cooler, with ice, and Chain of Custody documentation to MCCAMPBELL ANALYTICAL INC. , a California State Certified Laboratory, located in Pacheco, CA. ANALYTICAL RESULTS The analytical methods are those required in the "Tri-Regional Guidelines" which are directives of the Regional Water Quality Control Board and required by the SJCEHD. The analyses completed were for Total Petroleum Hydrocarbons, as gasoline (TPHG) ; Benzene, Toluene, Ethylbenzene and Xylene (BTEX) via EPA Modified Method 8020/8015 and for the Oxygenates using the EPA Method 8260. A cumulative Table to show groundwater fluctuations and the comparative results for the concentrations of the Oxygenates, TPHG and BTEX, in the four monitoring wells, are contained in TABLE 2. The analytical results, for the last two quarterly events of the groundwater sampling from the Monitoring wells, identified as MW- 1, MW-2 , MW-3 and MW-BT in ug/L, i.e. parts per billion (ppb) , for Oxygenates, TPHG and BTEX are shown in Table 2. The Laboratory Data Sheets, along with detection limits, and Chain of Custody documentation are contained in t.ppendix B. SUMMARY, CONCLUSIONS AND RECOMMENDATIONS The calculated groundwater gradient is N250E or 0250 . The water levels in the monitoring wells has risen since the last water levels were taken. This rise is most likely due to the heavy rains experienced in this local for the last three months. i MW-1 had No Detectable concentrations of TPHG, BTEX or the Oxygenates. i MW-2 had less than 1 PPM TPHG and 1. 3 ppb MTBE contamination. MW-3 had 180, 44, 0.76, and 0.53 ppb of TPHG, Benzene, Toluene and Ethylbenzene respectively. No detectable concentrations of Xylene and 2 ppb MTBE contamination were reported. 3 i i i