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plan views of the project area. These maps were not done to County and Tri--Regional format in matters of orientation and scale. The previously submitted excavation plan, herein att- ached, was drawn with south at the top of the map. These are good diagram: and this report continues this orientation. Also, it was not poFsible to draw the area map, Figure 8, to a 1" = 20' scale owing to computer-p:''nter size limitations; therefore, Fig-are 8 is approximately 1" = 30' and the zoom projection, Figure 9, is about 1" = 16' (bar graphs are in- eluded) . Figures 10, 11 and 12 are cross sections of the tank excavation and of. the Key Lock pump area. The cross sections have the sample data showing contamination on them as well as projected locations of proposed test holes. Their scales are about 1" = 20' . Their orientation conforms to the maps, and is not right side to the north or east. In the tank excavation area, it appears that the major contamination is near the loading racks, southerly of the excavation and/or is related to the pipeline connections to the Xey Lock pumps location. The highest readings found were at sample Location #1 '12, the one in closest proximity to the '_oadinc racks, which could easily be a source of spills. After leaving the area of excavation for tank removals, no contaminated samples were found under the pipelines until- reaching ntilreaching Sample Locations 8 and 9, located near and under the Key Card pump area. Sample 9 had a TEH reading of 1100 mg/kg, about 10 times higher than any other sample reading. No other sampling was done in this area. Inasmuch as the TVH readings- were far less than the TEH readings, it appears that the major leak in the pump area was diesel fuel . WORK PLAN FOR DELINEATION OF THE CONTAMINATION It does not appear that further excavation is warranted at this time because the limits and direction of the contam- ination are not known. The use of a shallow drilling capability auger and split spoon sampler is currently being investigated. If this rig appears capable of taking samples to about 12 feet below ground level , it 1s proposed that' 1 . 7 auger holes be drilled and .3ampled around the Key Lock pump area. The holes should be drilled to about 12 feet below ground level and samples col- lected at -21 , -7' and -121 . The samples shvu'd be tested for BT_EX, TPH•-G and TPI~-D, using standard DHS recommended methods. The DHS is to be notified of the sampling and any other test run that they might require. Inasmuch as Ethy:ene d;bromide and Inorganic lead were not found zn any previous test, it is not felt that further testing for them is needed. 7