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• the asphalt zn two locations in the midcle of where the tanl mad been located , and obtaining soil samples using a bacl-hoe oucPat. The operation was witnessed by San Joaquin Co. EHD personet . 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 Forwaro , Inc. work began. on November 5, using a Jim Thorpe Oii JD r,90C e-ca,tia- tor operated by Rich Thorpe. W. J. Hunter , RG, supervised Opel--- ations, which were witnessed by Michael Collins of the County EHD. Starting at the north end of the site, the aspha.ir. covering and the clean fill was removed by the e\a avator bucket and stored against the south property line using a backhoe operated by Jamie 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 parkea adjacent to the e'r-avation. 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 buf " clay, • farm but not plastic , with occassional streais of clay lavers. Tnere were no odors or e,r!QenCe of contamination, notee. Using the e,cavator bucket , a soil sample was taken from the bottom center of the e,cavaLion, ( 12 deep , ) abour. 5 feet from the north wall . Using a clean , 2" � c,' grass tube, ts-ie geoloa )isF collected a sample from the teeth of the bucket. It "as quacit' ,,, sealed with teflon tape and plastic end caps, and wrapped with dict tape. Tr:e sample was labeled and olaced on ice pending transport to the laboratorv. That sample . s laentified as "Btm-No. ( 12 ) on Plates VI & VIZ . At this point , the truck was full , ani while it was transport:.ng 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 emptv truck, kwhich had returned from Forward. ) At this time, the size of the e�,cavation 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 remo,�ed spoil revealed obvious staining and discoloration. As digging progressed, the contamination appeared to be stronges-t on the east and south wall , and the bottom. The west wall dad n,ot • 4