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J .- • S m lin Ev —01 On March 10, 1989, the soil in the area about Sample Point 31035 was excavated an additional 6 feet in depth (from 8.5 feet to 14.0 feet below ground surface). The 14 to 17 cubic yards of additionally excavated material was stock-piled on plastic sheeting near the excavation. Soil 8.5 to 11.0 feet below ground surface consisted of red-brown silt to fine- grained sandy silt. At a depth of approximately 11 to 13 feet, a lense of gray-colored soil was encountered. The gray-colored soil had a sewage-type odor. Below the lense of gray soil, the red-brown silt to sandy silt was encountered again. After the excavation was completed, the gray colored soil was visible on the north side wall, but not visible on the south, east, or west sidewalls (Plate 3). A Kleinfelder geologist collected two samples of native soil from the excavation. Sample 22926 was collected from the floor of excavation at a depth of 14 feet, and Sample 22927 was collected at a depth of 13.5 feet from the north sidewall. Both samples consisted of a red-brown silt to fine-grained sandy silt, moderately to well cemented. The locations of the excavation sampling points from the February 23 and March 10, 1989, sampling events are shown on he Sample Location/Cross-Section Location Map (Plate 3) and Cross-sections A-A" and B-B' (Plates 4 and 5). Soil samples were obtained in clean brass tubes. Sample tubes were decontaminated prior to sampling by washing in a solution of trisodium phosphate (TSP), followed by a distilled water rinse. Each tube was retracted, capped with Teflon sheeting and tightly fitting plastic end caps. Samples were labeled, logged on chain-of-custody and stored on ice until delivery to California Analytical Laboratories/ Ms, atorie / ns cwas o inVresentest athroughout thlef oampli g representative from the SSJJLL P process. A photoionization detector (PID) was used in the field to screen the soil for volatile organic consultants 103 eV. Neither a soil samples showed spil above ambient background The gray oil had PID reading of 65 parPID million by volume. Analytical Results The samples were EPA Method 8020. Ile samplezed for s Pere analyzed extractableori a one-week rush turnaround s B d e by TPH and BTEX constituents were below laboratory reporting limits in Samples 22926 and 22927. 1n Sample 22927 collected from the wall of the excavation, a late eluting (heavy) hydrocarbon was indicated. The hydrocarbon was not indicative of fuel hydrocarbons or diesel associated with the tank. It ra _stained soil on the north side of the excavationexcavated, The late eluding hydrocarbon cot Ie associated with d nat be quantified or identified further. Based on the analytical results, the hydrocarbon contaminants associated with the excavated diesel tank appears to have been removed. Meinfelder recommends a copy of this report be submitted to the SJLHD for their review. If you have any questions or require our services any further, please do not hesitate to contact us.