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1 1� 28 February 2003 AGE-NC Project No 95--0135 Page 3 of 4 r I TPH- was detected in waters les collected from the monitoring wells MW-1 and MW-2 TPH�-g g � g was detected at concentrations as high as 7,100 micrograms per liter (�ig/1),-in MW-1A Benzene was detected in samples MW-1A, MW-1B, MW-2A and MW-2B at a maximum concentration of 1,100 µg/1 (MW-IA) Toluene, ethylbenzene and xylenes were detected in the sample MW-lA, MW-2A and MW-2B at niaxnnum concentrations of 66 µg/1(toluene in MW-2A), 550 �ig/l(MW-IA) and 208 µg/l(MW-lA),,respectively DIPE was detected in water sample MW- 2A W2A at a concentration of 30 µg/1 MTBE was detected in sample MW-2B at a concentration of 29 lig/l. ' No other target analytes were detected in the samples analyzed The analytical results of groundwater samples are sunmiarized on Table 2 The laboratory report(CalTech laboratory ID 0302-027-1 to-6), Quality Control and Quality Assurance (QA/QC) and chain-of-custody are in Appendix C 4.0. SUMMARY/CONCLUSIONS The following conclusions were drawn from the results of this investigation During the January 2003 monitoring event,the shallow ground water flow direction at the site was generally toward the north-northeast ,Ground water elevation had decreased an average 1 5 feet between the last two monitoring events The analytical data from samples MW-i and MW-2 indicated that the highest concentration of dissolved hydrocarbons are on the western portion of the site • Monitoring well MW-3 appears to be located beyond the eastern margin of the dissolved hydrocarbon plume ' The fuel additive MTBE was detected in a water sample from well location MW-2, adjacent to the former UST area, the MTBE concentration (29,�Lg/l) exceeds the State of California maximum contaminant level of 10 µg/1 in'drinkmg water The lateral extent of dissolved hydrocarbons is not defined to the north of wells MW i and MW-2 nor CPT3 , i 5.0. RECOMMENDATIONS' Advanced GeoEnvironmentab Iuc 1 A