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. 29 June 2001 ' AGE-NC Project No. 98-0468 ' Page 3 of 4 ' 3.1. GROUND WATER ELEVATION AND FLOW DIRECTION During the 12 June 2001 monitoring event,the depth to ground water at the site ranged from 10.38 ' to 13.14 feet below the tops of well casings (btoc) in wells MW-1 through MW-5. Ground water wells MW-6 through MW-8 have not been surveyed.and were not utilized to determine•the ground water flow direction or gradient (Table 1). Ground water elevation at the site ranged from 3:49 to 4.07 feet below mean sea level (MSL). Ground water elevation in the monitoringwelis decreased an average of 0.8 feet since the previous monitoring event. A summary of depth to ground water and ground water elevation measurements is presented in Table 1. ' A ground water elevation contour map for June 2001 is illustrated on Figure 3. Based on ground water elevation data, ground water flow direction Is inferred to be toward the northeast. Ground ' water gradient for the latest sampling event was calculated to be 0.01. In general, ground water flow ' direction and gradient for this monitoring event appear'to be consistent with previous monitoring events results. 3.2. LABORATORY RESULTS OF GROUND WATER SAMPLES Ground water samples were collected from MW-3 through MW-8 for laboratory analysis. A summary of ground water analytical results are presented in Table 2. The laboratory analytical report is included in Appendix B. There were no reported detections of BTEX compounds or TPH-g in the ground water samples ' analyzed during the June 2001 monitoring event (Table 2). MTBE was reported in the ground water samples collected from monitoring wells MW-4 and MW-6 ' at.concentrations of 110 micrograms per liter (,ugll) and 170 µg/1, respectively, by EPA Method 8020.MTBE was reported in the ground water samples collected from monitoring wells MW-4 and MW-6 at concentrations of 100,ug/l and 150µg11, respectively, by EPA Method 8260. ' n samples exceed the DHS - established maximum contaminant The MTBE concentration l theses p • level (MCL)•of 5µg/1 for MTBE in ground water. The DHS action level for MTBE is 13 µg/1.There ' were no reported detections of any other fuel oxygenating compounds. Laboratory results of ground water samples analyzed for petroleum hydrocarbons, fuel additives and ' VOCs are summarized in Table 2. The laboratory reports (MAI Laboratory ID: 69679 to 69684}; . quality assurance and quality control (QA/QC) reports and chains-of-custody are included in. Appendix B. Advanced GeoEnvironmental,Inc.