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} _ &M01Wen Union Ice Company - Weber Street Phase II-Repo,; ;f Findings Page 9 Inspection of Plate 7 and Table 2 shows that all of the contaminated soils were excavated except for a small finger of contamination in the southeast corner of the excavation. The excavation was discontinued here because of the presence of the sewer line. Sample S-7, taken in thi, portion of the excavation, shows that the contamination is at a depth of about 11.5 feet. It appears to be feathering out in that direction (Plate 6). On March 7, 1991, a small backhoe trench was opened about 10 feet east of sample location S-7. Samples from this trench show that the soils contamination continues to this area. Samples taken from 10 feet and 15 feet depths from MW-8, which was drilled about 25 feet southeast of the backhoe trench, show that the contamination feathers out in that direction. We are proposing that four(4) exploratory borings be drilled in an arcuate pattern, sur- rounding the backhoe trench, to define the extent of this contamination. Once the geo- metry of the remaining soils contamination is understood, its potential to further con- taminate ground water will also be understood. We can then decide whether to leave it in place or remove it by further excavation. GROUND WATER CONTAMINATION Evidence of BTE&X contamination was detected in Wells 1S, ID, 2S, 3S, 4S, 4D, 5S, 6S and 7S during this investigation. Results of the sampling of these wells are shown in Table III. Wells 1S and 1D showed presence of contaminates during the March and April samp- ling rounds. These wells are up-gradient wells. The contamination detected tll em may have an off-site source; possibly, an off site leaking storage tank or, perhaps, spills from vessels using the ship canals. There have been no contaminates detected in these wells since April, 1990. Samples from well 2S contained very minor levels of Toluene and Xylene in March and April of 1990. This well has sampled clean since that time. Well 3S showed minor Toluene contamination in March, 1990. This well has ,ampled clean since that time.