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900 mg/L of TPHg; the sample at 46 ' measured 0 26 mg/kg of ' benzene, 0 . 13 mg/kg of ethylbenzene, & 65 mg/L of TPHg Toluene & xylene were below detection levels PLATE VII gives details of lithology, blow counts, PID readings, & comments . Soil boring "B" - This soil boring was placed adjacent to the former pump island for the purpose of evaluating the possibility of leakage from the dispensing pumps and/or product lanes The results of the laboratory analyses confirm that indeed that area was a mayor contributor to the contamination encountered beneath the property Ethylbenzene, toluene, xylene & TPHg were found an ' all soil samples taken from 16 ' bgl to 511 . Benzene was detected an all samples from 26 ' to 51 ' bgl . As can be seen on PLATE IV, PID readings of cores taken at 251 , 301 , 351 , 401 , & 45 ' bgl exceeded the maximum of the meters capability - 2, 000 ppm The ' sample at 50 ' recorded 1051 ppm, laboratory results {TABLE XIII} revealed significant levels of BTEX & TPHg. All of the soil samples were non-detect for MTBE . PLATE XI shows the potentaometrac surface based upon the 7/1/1996 sampling event The gradient is to the northeast at about 0051 / foot . The direction as almost identical to those measured an 6/95 & 10/95, the 2/96 event revealed a shift to the southeast Both monitoring wells #2 & #3 are an a downgradient position from ' the removed UST' s MW-2 is closest to the tank site, but MW-3 has consistently measured higher levels of contamination The placement of soil boring "B" adjacent to the pump island, ' revealed extensive contamination in all soil samples below 16 ' That indicates either the fuel dispensers, product lanes, or both, may be the mayor source of contamination That also accounts for the high levels of gasoline products measured in the ' water samples from MW-3, which as only about 10-15 ' from the pump island The water table was measured at an average depth of 37 58 ' bgl, a rise of 5 61 ' since the February sampling This rise an water levels has been observed an most of the Stockton area, due most likely to higher than normal rainfall this past season ' The results of the analyses of water samples from the sax wells as summarized on TABLE A. The highest levels of ethylbenzene, ' toluene, xylene & TPHg were measured an MW-3 ; MW-5 had the highest level of benzene . MTBE was only measured in MW-2 , MW-4, MW-5, & MW-6 ; at was not detected an MW-1 or MW-6 The reason ' for this anomaly is not known Perhaps later sampling events will clarify the matter ' 8