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Emergency Remediation- 2480 Tracy Blvd., Tracy, CA. • Page 8 When, at the laboratory, a specimen was taken from a sample, it was taken from near the bottom of the sample tube. This was done so that the analytical results would reflect the concentrations of analytes present in the soil at the maximum depth to which the probe had penetrated beneath the ground surface. All nine soil samples recovered using the push probe were analyzed for the following suite of analytes. fAnalyte Method of Analysis Total Petroleum Hydrocarbons EPA Method 5030/8015 (as Gasoline) Benzene EPA Method 8020 Toluene EPA Method 8020 Ethyl Benzene EPA Method 8020 Total Xylene Isomers EPA Method 8020 Findings The results of the analyses of the soil samples recovered in the push probes are presented in Table 2. These data show that soil under the former site of the Chevron service station at 575 West Grant Line Road is affected by gasoline and that contamination has extended down the groundwater gradient, affecting the subsurface beneath the 2480 Tracy Boulevard property. Total petroleum hydrocarbon concentrations detected in the samples obtained with the push probe range from 210 ppm (parts per million) to 1,200 ppm. Moderate concentrations of BTEX compounds are present in all of the samples, although, with two exceptions, benzene and toluene were below detectable concentrations. The discrete specimens extracted from the push probe sampler for analysis at the laboratory represent the soil at depths between approximately 8.2 ft and 9.5 ft beneath the original ground surface. When the data from the extended site investigation is combined with the results of the soil and groundwater analyses obtained from the sampling performed during the initial evaluation of the contamination found to be affecting the property, it is apparent that components of gasoline are present over the entire area of the subject property in a zone extending from about seven feet below the ground surface, which elevation is some 0.75 ft above the water table (at its the elevation in April 1996), to some undetermined depth