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Figure 3 shows the groundwater table levels in June of 1986, 'r 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 ` 421 . 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 101 , on average, within the upper 100 ' . There are no known water wells on or near the property. Wells in the general area are completed in the 150 ' to 250 ' 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-of-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