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Greer Property I S634 Steinegul Road September 9, 2000 Escalon, California Page. 7 Report of Findings and permeability from the 45' b g 1 were 0 3378 and 1 2x104 cm/sec, respectively Based on these values, the upper vadoze zone does not exhibit properties conducive to vapor extraction However, the lower vadoze zone does exhibit some properties conducive to vapor extraction Appendix F provides that ' laboratory analytical data for the hydraulic parameters Vapor Extraction Well VE-2 Vapor extraction well VE-2 was not sampled for the chemicals of concern but was analyzed for the hydraulic properties. One (1) sample from this well, VE-2 ' at 70' was analyzed for hydraulic parameters. The porosity of this soil sample was 0.4033 and the permeability rate was 6.9x10-7 cm/sec These parameter values are not conducive to the extraction of vapor Appendix F provides that ' laboratory analytical data for the hydraulic parameters ' 4.2 Groundwater Analytical Results The groundwater analytical data is presented in Table 2 The laboratory analytical ' data for the groundwater can be found in Appendix C of this report The groundwater analytical results revealed the presence of Benzene in concentrations between ND to 4,600 ug/L, Toluene was found between ND and 2,700 ug/L, ' Ethyl-Benzene between ND and 320, Total Xylenes between ND and 1,400 ug/L, and gasoline between ND and 23 mg/L Only two of the six oxygenates were found to be present !n the water samples These are identified as Tertiary Butanot ' (TBA) and MTBE TBA was found in wells MW-1, MW-5, MW-6, and MW-9 and ranged in concentration from 54 ug/L to 99 ug/L MTBE was found in N1W-1 ' and MW-6 at 3 7 ug/L and 150 ug/L, respectively The groundwater samples from the wells MW-8, MW-10, and the domestic well ' on site were ND for all analytes ' 5.0 Georogylxydrology The subject property is located on the western side of California's Central Valley The Central ' Valley is approximately 400 miles long and averages 50 miles wide encompassing approximately 20,000 square miles The valley is a large asymmetric trough that is bounded by granitic, metamorphic and mann sedimentary rocks of pre-tertiary age This trough has been ' filled with as much as 30,000 feet of sediment in the San Joaquin Valley portion to the south, and as much as 60,000 feet of sediment in the Sacramento Valley portion to the north ' The age of the sediments range from Jurassic to Holocene and include both marine and continental rocks and sedimentary deposits(Olmstead and Davis, 1961)