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f 4 ` 4 07 May 2004 AGE-NC Project No 98-0534 ' Page 5 of 14 'J �ti�1� at concentrations up to k6"µg/l in sample P7-water Other BTEX compounds were also ' detected at concentrations as high as 1,100 µg/l (xylenes in P3-water) MTBE (by EPA Method` 8020) was detected in sfx of the water samples analyzed at ' concentrations ranging from 6 3 µg/1 in sample P8-water to 1,200 µg/1 in sample P9-water MTBE,ETBE and TBA were detected by EPA Method 8260 Modified in nine of water samples analyzed at a maximum concentration of 1,600 µg/1 in sample,P9-water (MTBE) The analytical results of selected soil and ground water samples are summarized in Tables ' 2, 3 and 4 Field procedures and sample results for the June 1999 excavation were reported in Preliminary.Investigation and Evaluation Report, dated 18 April 2000,prepared by AGE • 20 and 21 July 2000, eight pilot borings were advanced to 30 feet bsg and completed as ' monitoring wells (MW-1 through MW-8) utilizing 2-inch diameter PVC well casing As- built monitoring well diagrams for MW-1 through MW-8 arc shown on Figure 3,boring logs for wells MW-1 through MW-8 are included with Appendix B Discrete soil samples were collected at 5-foot intervals, beginning at 5 feet bsg, to total depth of each boring with the exclusion,of MW6 In boring MW6, soil samples were collected at two-foot intervals, � . starting at 10 feet bsg A total of twenty soil samples were submitted to MAT for analysis of TPH-g,TPH-d,BTEX, MTBE, ETBE,TAME,DIPE,TBA, 1,2-DCA and EDB None of the above mentioned fuel components were detected by laboratory analysis The analytical results of selected soil samples are summarized in Tables 3 and 4 Results of the July 2000 investigation were reported in Quarterly Report-3rd Quarter 2000, dated 09 October 2000,prepared by AGE • 02August 2000-the casing elevation of each installed well was surveyed to the nearest 0 01- , I foot,relative to well MW-1 assigned a relative,arbitrary elevation of 5 00 feet Initial ground water levels measured at MW-1 through MW-8 averaged 10 38 feet below the tops of the well casings, ground water was inferred to be flowing to the south and southwest with a r nearly flat hydraulic gradienf of 0 003 feet/feet TPH-g w snot detected in any of the aground water:samples _TPH_d,was only detected in_samplesA W-4-and MW-6-at.41�0 µg/Land 82 µg/1,respectively-Of the BTEX compounds,only toluene was detected in sample MW-4 at 0 63µg/l MTBE was detected in samples MW-3, MW-4, MW-6 and MW-7 at 3 7 µg/1, 13 µg/1, 350 µg11 and 2 2 µg/1, respectively ETBE was detected at 24 µg/1 in sample MW-6 and TBA was detected at 21 µg/l in sample MW-4 -No other petroleum hydrocarbon Iconstituents or fuel oxygenating compounds were detected during the laboratory analysis The results of the monitoring well survey and ground water elevations are summarized in I Table 1, analytical results of ground water samples are summarized in Table 2 Results of the August 2000 ground water monitoring event were reported in Quarterly Report - 3rd ,• Quarter 2000, dated 09 October 2000, prepared by AGE Advanced GeoEnvironmental,Inc