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1 1 ' the asphalt in two locations in the middle of where the tank had been located, and obtaining soil samples using a backhoe bucket. ' The operation was witnessed by San Joaquin Co. EHD personel . The soil samples were analyzed as required by the waste disposal firm so that removed spoil could be taken directly to the ' disposal site as it was excavated. After County approval of the workplan, and arrangements had been ' made to transport the removed spoil directly to Forward, Inc. - work began on November 5, using a Jim Thorpe Oil JD 690C excava- tor operated by Rich Thorpe. W. J. Hunter, RG, supervised open ations, which were witnessed by Michael Collins of the County ' EHD. Starting at the north end of the site, the asphalt covering and the clean fill was removed by the excavator bucket and stored against the south property line using a backhoe operated by Jamie I Thorpe. After removing the clean fill to a depth of about 5-6 feet , the original removed soil was encountered. That material was placed directly in a dump truck parked adjacent to the excavation. The north end was excavated to a depth of about 12 ' feet , with dimensions of about 12 feet wide and 20 feet long. The top 2--3 ' consisted of black adobe loam, very sticky and plastic. The adobe graded irregularly to a tan to buff clayr firm but not plastic, with occassional streaks of harder clay layers. There were no odors or evidence of contamination noted. Using the excavator bucket, a soil sample was taken from the ' bottom center of the a<cavati on, ( 12 deep, ) about 5 feet from the north wall . Using a clean , 2" X ti" brass tube, the geologist collected a sample from the teeth of the bucket. It was quickly sealed with teflon tape and plastic end caps, and wrapped with I duct tape. The sample was labeled and placed on ice pending transport to the laboratory. That sample is identified as "Dtm-No. ( 12 ' ) on Plates VI & VII'. ' At this point, the truck was full , and while it was transporting the material to Forward Inc,. for disposal , the removed spoil was placed on the asphalt pending the return of the truck_ The excavator moved to the south end of the excavation, and soil removal continued. The clean fill was stored in a separate pile than the underlying spoil , which was placed in the empty truck , ' (which had returned from Forward. ) At this time, the size of the excavation was approximately 12 ' wide and 30 ' long, grading from 12 deep at the north end to about 9-10 at the south. While removing spoil from a depth of 10-12 , about 20 feet from the north end, a very strong petroleum odor was noted , and the removed spoil revealed obvious staining and discoloration. As digging progressed, the contamination appeared to be strongest on the east and south wall , and the bottom. The west wall did not I 4