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. __ _ ___ samples were contained, preserved and transported to Sequoia Analytical Laboratories, a state certified hazardous waste laboratory, in accordance with EPA protocol. The samples �. were analyzed for BTEX ,and TPH as diesel by SPA methods 8015/80200 3.0 SUBSURFACE CONDITIONS 3. 1 Field Inspection The soils encountered during drilling consisted ` predominantly of lean clays and clayey silts to 24 feet, the maximum depth explored. Saturated soils were detected at 9 feet below grade. Water levels stabilized slightly at approximately this depth in the wells. Hydrocarbon odors were not detected in the three borings. � The shallow groundwater gradient was calculated using well- head elevations (surveyed to an approximate mean sea level datum) and three rounds of water level measurements ('Cable 3) . The monitorings indicate the groundwater gradient is generally northwest at approximately 0.003 ft/ft (Figures 3, .•• 4, and 5) . 3. 2 Laboratory Analysis - Soils ` The laboratory analysis of the 8.5 foot samples from the monitoring wells reported non-detectable concentrations of BTEX and TPH as diesel. The sample analysis of hydrocarbon constituents for each boring is summarized in Table 1. The laboratory data sheets andchain-of-custody form are presented in Appendix II. 3.3 Laboratory Analysis - Groundwater Laboratory analysis of groundwater samples recorded below action, yet detectable. levels, of toluene in MW1 and MW2. All other hydrocarbon constituents were below method detection limits. The water sampling results are summarized in Fable 2. The laboratory data sheets and chain-of-custody form are presented in Appendix III. 4.0 CONCLUSI0NS The investigations conducted to date have documented diesel contamination only in groundwater beneath the site. Laboratory results reported less than a part per billion (ppb) of toluene in two of the three wells. Toluene was the only hydrocarbon constituent detected. 2