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contained too much silt and could not be purged. Personnel returned to the site on October 18, 1993 to redevelop the wells and perform third quarter monitoring procedures. The wells were redeveloped by surging and purging each well with a PVC bailer to remove the silt. I A Solinist water level meter was used to measure the depth to groundwater in the three monitoring wells on October 14 , 1993 . After water levels were measured, PVC bailers were used to purge approximately 8 gallons of water from each well, to stabilize ' temperature, pH and conductivity (Table 1) . The purge water was placed in DOT-approved drums and stored on-site. I3 . 5 Water Sample Collection and Analysis Water samples were collected from each well using new disposable plastic bailers. Three 40 ml EPA vials of water were collected from each well and transported in a chilled container to STI in Sacramento. Each sample was analyzed for total petroleum hydrocarbons (TPH as gasoline) and volatile aromatics (BTE&X) in ' accordance with EPA methods 8015m and 602 . 4 . 0 FINDINGS 4 . 1 Excavation 4 . 1. 1 Excavation Soil Sampling Soil was excavated to a depth of 30 feet during the first phase of ' digging. Most of the soil samples collected after the first phase were uncontaminated; however, one sample from the floor and two samples from the west wall of the excavation contained hydrocarbons ' (Table 2) . TPH as gasoline and benzene were detected in the floor sample (B1-32) at 5, 900 Ag/g (parts per million) and 11 ppm, respectively. Toluene, ethylbenzene and xylenes were also detected in samples B1-32 , as well as in wall samples W-26 and W-29. During the second phase of digging, the excavation was deepened to a depth of 39 feet. No contamination was detected in soil samples collected from the west wall of the excavation during this phase of excavation. Only sample B5-39 , collected from the floor of the excavation at a depth of 39 feet, had any detectable contamination: ' benzene was detected at 0. 006 ppm and toluene was detected at 0. 007 ppm. These values barely exceed the detection limit of 0. 005 ppm. The laboratory report and chain--of-custody are included in Appendix ' A. 4. 1.2 Stockpile Soil Sampling No contamination was detected in the soil samples collected from the "clean" stockpiled soil. The contaminated stockpiles have not been sampled and characterized The laboratory report and chain-of- 7