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i 11 . depth to groundwater gradually rose to about 65 feet below grade, and by June 1995 the groundwater level was about 60 feet below grade The groundwater gradient has been relatively consistent despite the fluctuations in elevation, with groundwater flow measured to be easterly under a gradient of 0 001- 0 003 On June 6, 1995 the hydraulic gradient was measured to be 0 003 to the east(Figure 4) The results of analytical soil testing indicates that soil samples from six well locations contained greater than 1,000 mg/kg TPH These well locations appear to be clustered in three separate areas (Figure 5) The first area is located along the west side of the property near the pump island and former western underground tank Soil samples from this area contained TPH concentrations of up to 4,100 mg/kg as found in sample TB4-10 The area is further defined by well locations MWS and TB6, which also had elevated contaminant levels in soil The second area is located near the center and to the east of the former tank cluster as defined by wells TB7, T1312, and MW2 Soil samples in this area contained up to 5,300 mg/kg TPH as found in sample T137-20 The third area is interpreted to be an isolated zone around boring/well TB3 This area had up to 5,700 mg/kg TPH as found at 30 feet below grade This location was the site of an unidentified subsurface fiberglass pipe that was discovered during site reconstruction The pipe was approximately 2-inches in diameter and appeared to run from the cashier's booth area north towards Harding Way There are no known uses for this pipe, but moderate hydrocarbon odors were noted in the surrounding soil Groundwater sampling results have shown that well MW 5, located near the western site boundary, consistently contains free floating product Each of the other wells has historically had high dissolved concentrations with up to 18,000 ug/l benzene detected in the groundwater The results of sampling from June 1995 show that only wells MW3R and TB 10 had less than 1,000 ug/l dissolved benzene (Figure 6) Page 3 i