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GROUNDWATER SAMPLING The wells were purged to dryness. The groundwater samples were collected via a clean bailer, placed in 40 ml VOAs, labeled, placed in a cooled ice chest and transported to a state certified laboratory (MCCAMPBELL ANALYTICAL INC. ) under Chain of Custody (COC) documentation for analysis. The groundwater samples from MW- 1 and MW-2 wells had a hydrocarbon odor. ANALYTICAL RESULTS The analytical methods are those required in the "Tri-Regional Guidelines" which are directives of the Regional Water Quality Control Board and requested by the SJCEHD. The analyses completed were for Total Petroleum Hydrocarbons, as gasoline (TPHG) ; Benzene, Toluene, Ethylbenzene and Xylene (BTEX) and Methyl-tert-butyl ether (MTBE) via EPA Modified Method 8020/8015 . The results of the groundwater samples in ug/L (parts per billion (ppb) ) for TPHG, MTBE and BTEX are shown in Table 1. Laboratory Data Sheets with detection limits and a copy of the Chain of Custody (COC) are contained in Appendix B. SUMMARY, CONCLUSIONS AND RECOMMENDATIONS The calculated gradient is S 50 W or 2200 at 0 . 009 ft/ft. This is a generally southerly gradient. The direction and slope have changed back to southerly as was found in the majority of the prior calculated gradients. Based .on the analytical data from prior quarterly reports, it appears that no or very low detectable concentrations of MTBE are impacting the groundwater at this site. The groundwater beneath the site has been impacted and heavy gasoline and BTEX contamination were detected in the groundwater samples from MW-1 and MW-2. Consistent with prior results, lesser concentrations of gasoline and BTEX were detected in the sample from MW-3 . JPCA recommends continued monitoring of the wells to further evaluate the amount of contamination and consistency of the gradient. JPCA also recommends the pumping of groundwater from wells MW-1 and MW-2 to remove, if possible the higher concentration 3