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Figure 3 shows the groundwater table levels in June of 1986, a year with the highest levels in recent years . Estimating ✓ the surface as being +22 ' MSL, and the water table on this map as being -18 ' MSL, then the depth to groundwater would have been 40 ' below ground level (bgl ) . Figure 4 shows 1991 data with reference to ground level . It indicates the water table to be about 82 ' bgl , a drop of 42 ' . Figure 5 shows the wells that these data are based upon with the closest well about 1/4 mile away . The regional hydraulic gradient is in an easterly direction . California Department of Water Resources , Bulletin No . 146 shows essentially zero sand in the upper 50 ' of sediments and only about 10 ' , on average , within the upper 1001 . There are no known water wells on or near the property. Wells in the general area are completed in the 150 ' to 254 ' bgl range . EXCAVATION AND SAMPLING ACTIVITIES 4/21/92 GENERAL PROCEDURES Dennis Allen, (DRA) representing WJH, picked up sterile brass tubes and end caps for sample collecting at FGL Environmental , Stockton, CA, a California certified laboratory that would run all sample tests . All samples were hand collected using the above tubes ; Teflon end sealers were placed under the plastic caps and the samples were sealed with duct tape . All samples were collected from the back-hoe bucket during excavation and placed in a chest filled with crushed ice to await transportation to the laboratory . The technique used was to excavate in the area of contamination where either/or visible staining and hydrocarbon odors were found and to take samples when all obviously contaminated material had been removed . Back hoe samples were continuously examined for hydrocarbon odors by both DRA and Richard Thorpe . All samples were labeled on both ends with a laundry--type marker and on the side with a sticker label . The depth and location for each sample was noted on both the sample and on the chain-o£-custody form . The approximate location for each sample is shown on Figure 6 . FGL QA/QC procedures have been filed with EHD previously , FGL QA/QC control numbers are shown on each sample sheet . EXCAVATION AND SAMPLING JTO commenced excavation at about 9 : 45 AM . JTO told DRA that permission had been given by EHD to return the clean portions of the spoil to the north and south ends of the existing excavation . This was done as shown on Figure 6 . EHD also had been informed of todays operations . An exposed water line was covered at the north end of the previous excavation. The contaminated, spoil from earlier excavating 3