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v � concentrations were found to decline toward the north end ofthe tank.Most likely a spill occurred near the south end of the 12000-gallon diesel tank. Installation of Monitoring Well MW#1 (a.k.a. USTI) MW#1 was installed on 5/14/2001 to a depth of+/- 55'. Soil samples were extracted by a split spoon sampler at five intervals and the samples were analyzed for BTEX and Oxygenates(see Soil Sample Recap attached). Twenty feet of screened two inch PVC case was installed from 35' to 55'. The monitoring well was developed and the first set of water samples were taken on 5/2412001.The first set of water samples was non-detect for all analytes.The following is a report on the second set of water samples from this monitoring well. PROCEDURE Water Sampling and Analysis Water samples from MW#1 were extracted by Del Tech Geotechnical Support Services on 10/22/2001. The sample was transported under chain of custody to BSK Laboratories for analysis for oxygenates by EPA Method 8260,EPA 8015(M)and EPA 8020.Pump rates were one G.P.M.Depth to the water surface was 50.73'with a+/-4'stickup on the casing.The water table at the time of sampling is about 46' below the surface. FINDINGS This second consecutive water sample was found to be non-detect for BTEX, TPHg, TPHd, and all oxygenates. . CONCLUSIONS This second set of monitoring well water samples was analyzed by BSK Laboratories. The first set of samples extracted on 05/24/2001 was analyzed by Sherwood Labs and Entech Analytical Labs.Both sample set produced identical results. The sample sets were non-detect for all analytes. RECOMMENDATIONS The excavations for the UST removals should be backfilled with a one foot layer of compacted low permeable soil(k= l x 10-6 cm/sec)at the base of the backfill. This low permeable soil will prevent surface water migration though the contaminated plume.The remainder of the backfill may be random backfill material. i 2. REQUEST FOR NO FURTHER ACTION REQUIRED ON THIS UST SITE The Potential for Further Soil and Water Contamination by UST Leaking Potential for additional diesel contamination has been removed from the site when the UST was removed. The Extent of the Contamination Found in the Soil Only the south end ofthe 12000-gal UST was found to be leaking during removal.MW1 was located adjacent to the south end of the removal excavation to determine the vertical limits ofthe diesel plume. The diesel contamination is limited to a maximum depth of twenty-five feet below the surface. Low concentrations of TPHd were found in the ten and twenty-five foot samples.TPHd Concentrations of 868 mg/Kg and 1550 mg/Kg were found at fifteen and twenty feet of depth respectfully. The graph below illustrates TPHD concentration found in the MW#1 soil boring.