Laserfiche WebLink
29 June 1999 <br /> AGE-NC Project No 97-0290 <br /> Page 5 of 7 <br /> 3.0. FINDINGS <br /> Results of laboratoryanalysis of water to collected <br /> y soil and ground ate samples and a discussion of data <br />' during field work follows <br />' 31 STRATIGRAPHY <br /> Sandy fill material was encountered in the samples collected at depths of 5 and 10 feet bsg in borings <br /> I VW1, SWI and SW2 Silty sand and sandy silt were generally encountered from surface grade to <br /> 30 feet bsg Poorly graded sands were generally encountered between 30 and 60 feet bsg Silt and <br /> sand lenses were observed throughout the site A hard silt to clay layer was encountered at a depth <br /> Iof approximately 60 feet bsg The boring logs are included as Appendix A Stratigraphic cross <br /> sections were presented in the Corrective Action Plan, prepared by AGE <br /> 3 2 ANALYTICAL C L RESULTS OF SOIL SAMPLES <br /> Organic vapor was detected in 31 of the 36 samples collected from borings VW1, SW1 and SW2, <br /> located near the former USTs location, at concentrations as high as 6,588 ppm(SW2 at 25 feet bsg) <br /> Organic vapor was not detected in soil samples collected from boring MW8, located approximately <br /> 130 feet east of the subject property <br /> TPH-g was in detected in 10 of the 13 soil samples analyzed during the current investigation at <br /> concentrations as high as 5,500 parts per million(ppm, reported as milligrams per kilogram) BTEX <br /> compounds were detected at concentrations as high as 5 9 ppm, 160 ppm, 45 ppm and 270 ppm, <br /> respectively (SWI at 20 feet) Analytical results of soil samples are summarized on Table 1 The <br /> laboratory report (AAL Batch No 99-0423-008) and chain-of-custody forms are included in <br /> Appendix B <br /> 33 GROUND WATER GRADIENT AND FLOW DIRECTION <br /> The depths to ground water ranged from 4181 feet to 43 03 feet below the tops of the well casings <br /> The elevation of ground water in each well was calculated by subtracting the depth to ground water <br /> from the surveyed casing elevations Ground water elevations ranged from 5 10 to 5 56 feet above <br /> mean sea level(MSL) Ground water elevation increased an average of 1 51 feet between 26 January <br /> and 30 April 1999 Ground water data is summarized on Table 2 <br /> Ground water elevation contours based upon the data for the April 1999 monitoring event is <br /> Advanced CcoEn-ironmcntal,Inc <br />