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GROUNDWATER SAMPLING <br /> The wells were purged to dryness. The groundwater samples were <br /> collected via a clean bailer, placed in 40 ml VOAs and 500 ml <br /> plastic bottles, labeled, placed in a cooled ice chest and <br /> transported to a state certified laboratory (MCCAMPBELL ANALYTICAL <br /> INC ) under Chain of Custody (COC) documentation for analysis. The <br /> groundwater samples from the three wells had a sheen on the sample <br /> surface. <br /> ANALYTICAL RESULTS <br /> The analytical methods are those required in the "Tri-Regional <br /> Guidelines" which are directives of the Regional Water Quality <br /> Control Board and requested by the SJCEHD. <br /> The analyses completed were for Total. Petroleum Hydrocarbons, as <br /> gasoline (TPHG) ; Benzene, Toluene, Ethylbenzene and Xylene (BTEX) <br /> and Methyl-tent-butyl ether (MTBE ) via EPA Modified Method <br /> 8020/8015 . <br /> The results of the groundwater samples in ug/L (parts per billion <br /> {ppb} ) for TPHG, MTBE and BTEX are shown in `fable 2 . <br /> TABLE 2 <br /> ppb <br /> Sample ID TPHG MTBE B T E X__ <br /> MW-1 12, 000 ND 2 , 200 740 320 910 <br /> MW-2 140 , 000 ND 6 , 200 33 , 000 3 , 900 19, 000 <br /> MW-3 1 , 600 ND 120 370 39 180 <br /> Laboratory Data Sheets with detection limits and a copy of the <br /> Chain of Custody (COC) are contained in Appendix B. <br /> SUMMARY, CONCLUSIONS AND RECOMMENDATIONS <br /> The calculated gradient is S40o W or 2200 at 0 . 005 ft/ft. This is <br /> a generally southerly gradient. The direction and slope are <br /> similar to the prior calculated gradients. The gradient direction <br /> is inconsistent with the assumed regional gradient. <br /> Based on the analytical_ data from this and prior quarterly reports, <br />• 5 <br />