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After purging and prior to collecting the groundwater samples, the water depth was measured again from a mark located on the top of the casing, all four wells were fully recharged. The groundwater samples, from each well, were collected in four, laboratory certified 40 ml pre-cleaned glass VOAS, with Teflon 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 , Toluene, Ethylbenzene and Xylene (BTEX) gasoline (TPHG) ; Benzene 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 'j TABLE 2 . � The analytical results, for the last five 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 Appendix B. SUMMARY, CONCLUSIONS AND RECOMMENDATIONS The calculated groundwater gradient is N110W or 3490at 0 . 003 ft/ft. The water levels in the monitoring wells have increased since the last water levels were taken. This increase is most likely due to the rains experienced in this locale for the last three months. All wells recharged completely in less than an hour. MW-1 and MW-3 had No Detectable concentrations of TPHG, BTEX or the oxygenates. TABLE 2 PPB ND < l PPB MTBE 3