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31 October 2003 AGE-NC Project No 01-0839 Page 4 of 7 I Water samples were collected from each purged well using new disposable plastic bailers or a pre- cleaned inertia pump after allowing the wells to achieve a minimum 80%recovery of the pre-purge water volume Each water sample was transferred into three 40-m1 VOA vials containing 0 5 ml 18% hydrochloric acid as a sample preservative After collection, the samples were properly labeled, placed In a chilled container and transported under chain-of-custody to Cal Tech Environmental Laboratories(CTEL),a California Department ofHealth Services-certified analytical laboratory,for Ianalysis The samples were analyzed for a TPH-g in accordance with EPA Method 8015M, and • BTE&X, MTBE, DIPE, ETBE, TAME, TBA, 1,2-DCA and EDB in accordance with EPA Method 8260B I 3.0 FINDINGS The soil stratigraphy, ground water elevation, flow direction, and gradient were determined from field data The contaminant impact to soil and ground water was quantified by the laboratory analytical data 31 STRATIGRAPHY Generally, red brown to yellow brown, dry to slightly moist, clayey silts to clayey sands were encountered from surface grade to approximately 25 feet below surface grade (bsg) Yellow brown fine sand was generally encountered between 25 feet and approximately 35 feet bsg From I approximately 35 feet bsg to 60 feet bsg the stratigraphy is dominated by yellow brown to red brown clayey silt Yellow brown clean sand are encountered at approximately 60 feet bsg to 80 feet bsg The soil boring logs are provided In Appendix B Selected soil samples were sent to Cooper Testing Laboratoryand analyzed for geotechnical I properties The soil sample collected from MW1 at 25 feet bsg is described as a brown clay with sand, with a porosity of 42 2% to 44 7%, and an average permeability of 2 Ox 10-5 centimeters per second (cm/sec) The soil sample collected from MW2 at 35 feet bsg is described as a brown silty claywith sand, with a porosity of 38 6%to 40 0%, and an average permeability of 1 Ox 10-'cm/sec The soil sample collected from MW1 at 60 feet bsg is described as a yellow brown silty sand,with a porosity of 45 9%,and an average permeability of 3 Ox l O'cm/sec The soil sample collected from I MW2 at 75 feet bsg is described as a brown silty sand to near sandy silt, with a porosity of 41 1% to 414%, and an average permeability of 1 Ox 10-5 cm/sec The soil sample collected from MW4 at IAdvanced GeoEnvironmental,Inc