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I Sa,mpjiniz Event 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 110 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 wail, 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 the Sample Location/Crass-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 Each tube was retracted, capped with Teflon sheeting and tightly fitting plastic end caps Samples were labeled, logged on chain-of-custody and stored on ice until delivery to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/Enseco in West Sacramento, California A . representative from the SJLHD, Ms. Lititia Resch, was present throughout the sampling process A photoiomzation detector (PID) was used in the field to screen the soil for volatile organic consultants below 10 3 eV Neither of the two soil samples showed PID readings above ambient background levels The gray soil had a PID reading of 65 parts per million by volume Analytical Results The samples were analyzed for TPH extractable (Method 3550) by GC/FID, and BTEX by EPA Method 8020 The samples were analyzed on a one-week rush turnaround schedule. TPH and BTEX constituents were below laboratory reporting limits in Samples 22926 and 22927 In 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 excavated tank It may be associated with the gray-stained soil on the north side of the excavation The late eluding hydrocarbon could not be quantified or identified further (�ased on the an results, the hydrocarbon contaminants associated with the xc vated diesel tank appears to have been removed Kleinfelder 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