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Site Characterization Report: 7500 West Eleventh Street. Tracy, CA. Page 26 i groundwater recovered from PP-4 and MW-4 were 400 µg/L and 300 µg/L, respectively. The corresponding concentrations of gasoline in the groundwater at those locations were 880 µg/L and 52 pg/L, respectively. {Note: a similar relationship exists between the concentrations of MTBE in samples of groundwater recovered from MW-2, MW-3 and MW-4: MTBE was present in MW-3 at a concentration of 10,000 µg/L, but less than 1,000 µg/L in MW-4, and there was only 4.6 µg/L of that oxygenate in the groundwater sample recovered from MW-2.} r ; By examining the results of analysis of samples of soil recovered from PP-2, PP-3 and PP-4 and MW-2, MW-3 and MW-4 that are presented in Table 2, it can be seen that the distribution fuel hydrocarbons in the soil reflects their distribution in groundwater. With the exception of a trace of diesel detected in a sample recovered from a depth of 14 { ft, none of the soil samples recovered from PP-2, which was located just west of the ' = dispenser islands, contained any detectable concentrations of TPHd, TPHg or the BTEX compounds. Soil samples recovered from MW-2, located further to the west near the boundary of the 7500 West Eleventh Street property, were also free of any detectable sr} concentrations of TPHg or the BTEX compounds. However, a trace of an unidentified hydrocarbon in the diesel range was detected at a concentration of 1.90 mg/Kg from a soil sample recovered from a depth of 5 ft in that well boring. With the exception of traces of gasoline in a soil sample recovered from the shallow depth of 4 ft, samples from PP-4 were free of petroleum hydrocarbons. Low concentrations of diesel-range hydrocarbons up to 122 mg/Kg and gasoline-range f hydrocarbons ranging from 3.8 to 170 mg/Kg were detected in soil samples recovered from shallow depths in MW-4. No petroleum hydrocarbons were detected in samples recovered from deeper than 11 ft BGS in either boring. i Soil samples recovered from PP-3 and MW-3 revealed concentrations of diesel and gasoline that were generally elevated compared to those detected in the borings located to their east or west along the West Eleventh Street frontage of the subject property. Also, } ' petroleum hydrocarbons were found to be resent at particularly in the case of MW-3, p y p significantly greater depths in those borings than in borings to their east or west. However, the concentrations detected in the samples recovered from the MW-3 and PP-3 . borings are, in absolute terms, very low. The maximum concentration of diesel detected in the samples recovered from PP-3 was only 54 mg/Kg and the corresponding value for gasoline was 15 mg/Kg; similarly, the maximum concentration of diesel detected in i; samples recovered from MW-3 was 16.9 mg/Kg and the corresponding value for gasoline in a sample from that boring was 18 mg/Kg. The low concentrations of fuel hydrocarbons detected in soil samples recovered from PP- 3 and MW-31notable given the close proximity of those borings to the over-excavated Dispenser Pit, from which soil affected by high concentrations of petroleum hydrocarbons was removed in December 1998. The absence of significant concentrations ' of analytes of concern in soil samples recovered from those borings indicates that Dietz Irrigation had over-excavated a sufficient area to successfully remove the soil most sic