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I <br /> 18 March 2005 <br /> AGE-NC Protect No 95-0128 <br /> Page 3 of 4 <br /> 3 2 ANALYTICAL RESULTS OF MONITORING WELL GROUND WATER SAMPLES <br /> TPH-g was detected in ground water samples MW-4, and MW-11A at concentrations of <br /> 110 micrograms per liter (µg/l) and 130 µg11, respectively BTEX compounds were detected in <br /> sample MW-4 at concentrations of 3 5 µg/1 ethylbenzene and 2 5 µg/1 total xylenes <br /> MTBE was detected in ground water samples MW-4, MW-5, MW-6, MW-IIA and MW 1B at <br /> concentrations ranging from 18 µg/1 in MW-6 to 130 µg/1 in MW-11A <br />' No additional target analytes were detected at or above laboratory reporting limits in the samples <br /> analyzed The analytical results are summarized in Tables 2 and 3 The laboratory report (CTEL <br /> Project No CT214-0501081), including quality assurance/quality control (QA/QC) and chain of <br /> custody forms for the quarterly monitoring event are included in Appendix C Documents confirming <br /> the upload of laboratory electronic deliverable format(EDF)files and depth to water measurements <br /> to GeoTracker are included in Appendix D <br /> 4.0. SUMMARY AND CONCLUSIONS <br /> The following conclusions were drawn from the results of this quarterly investigation <br /> • Ground water elevations measured during the January 2005 monitoring event ranged between <br /> 23 41 feet to 25 19 feet below MSL The depth to ground water decreased an average of <br /> 1 2 feet since the last ground water monitoring event The site ground water flow direction <br /> was inferred to be east-northeast towards off-site <br /> TPH-g was detected in ground water samples MW-4 and MW-11A, the highest <br /> concentration was reported in sample 130 µg/l <br /> • BTEX compounds were detected only in sample MW-4 <br /> • MTBE was detected in ground water samples MW-4, MW-5, MW-6, MW-11A and <br /> MW 11 B,the highest concentrations(>50 pg/1)were detected in samples MW-4,MW-5,and <br /> MW-I 1 A All of the detectable MTBE concentrations exceeded the primary or secondary <br /> maximum contaminant level (MCL) for MTBE in drinking water <br /> • The lateral extent of dissolved MTBE is defined,but the vertical extent has not been defined <br /> off-site under the centerline of the Pacific Avenue <br /> Advanced GeoEnvironmental Inc <br />