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by EA and by the PHS/EHD, that the groundwater elevation differences are due in part to seasonal agricultural groundwater pumping, and seasonal natural groundwater recharge. 4.3 Soil Analytical Results Soil samples were collected and submitted for laboratory analyses as described previously ' The soil analytical results are presented in Table 2. Soil analytical data sheets and chain-of- custody records are included in Appendix III. The analytical results of the soil sampling indicates that concentrations of TPH as gasoline (TPH-G) were detected in the soil collected from monitor wells MW2 through MW5. ' BTEX compounds were detected in the soil samples collected from monitor wells MW2, MW3 and MW4 The maximum concentrations of petroleum hydrocarbons detected in soil samples were from the samples collected at 25 feet below ground surface, at the historical ' highest seasonal groundwater elevation. No concentrations of TPH-G were detected in the soil samples collected from boring MW1. ' TPH-G were detected in the soil sample collected from boring MW2 at a depth of 25 feet below grade at a concentration of 22 mg/kg, at a concentration of 420 mg/kg in the soil sample collected from boring MW3 at 25 feet, and in the soil sample collected at 30 feet ' below grade immediately above first encountered groundwater at a concentration of 27 mg/kg. TPH-G was detected in the soil sample collected from boring MW4 at 25 feet below grade at a concentration of 160 mg/kg, and in the soil sample collected at 30 feet below grade immediately above first encountered groundwater at a concentration of 160 mg/kg. In the soil sample collected from MW5 at a depth of 25 feet below grade the TPH-G concentration was 12 mg/kg ' Analytical data indicated that no concentrations of BTEX were detected in the soil samples collected and analyzed from borings MW 1 and MW5. Ethylbenzene and xylenes were ' detected in the soil sample collected at 25 feet below grade from boring MW2 at concentrations of 0.024 mg/kg and 0.073 mg/kg, respectively, and benzene was detected at a concentration of 0 041 mg/kg in the soil sample collected from boring MW2 at a depth ' of 30 feet below grade immediately above first encountered groundwater. BTEX were detected in the soil sample collected from boring MW3 at a depth of 25 feet below grade at concentrations of 0 34 mg/kg benzene, 12 mg/kg toluene, 2 7 mg/kg ethylbenzene, and ' 14 6 mg/kg xylenes, and at 30 feet below grade collected immediately above first encountered groundwater at concentrations of 0.59 mg/kg benzene, 0 083 mg/kg ethylbenzene, and 0.2 mg/kg xylenes BTEX were detected in the soil sample collected ' from boring MW4 at a depth of 25 feet below grade at concentrations of 0 58 mg/kg benzene, 0 51 mg/kg ethylbenzene, and 2 9 mg/kg xylenes, at 30 feet below grade collected immediately above first encountered groundwater at concentrations of 0.082 mg/kg benzene, ' 0 088 mg/kg ethylbenzene, and 2 9 mg/kg xylenes, and a saturated soil sample at 40 feet below grade approximately 8 feet below the first encountered groundwater level at concentrations of xylenes at 0 011 mg/kg iiiaicai 12 1