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property through the excavation. The PVC line was removed during excavation procedures An eight inch storm drain line extended from the west side of the excavation to the east side and was removed prior to tank removal procedures The re-routing of the water main and the storm drain as well as a description of the existing underground utilities at the subject property are addressed in a separate letter. The depth of the excavation at the south end, prior to removing any soil, was approximately eight feet below the surface of the pavement. The depth to the stockpiled soil material decreased moving northward within the excavation. At approximately 30 feet south of the north end of ' the excavation, the stockpiled soil material was even with the top of the excavation ' An excavator entered the excavation at the north end and began excavating from the southern end of the excavation. The excavator removed soil from the excavation and placed the soil on the asphalt surface along the east side of the excavation. A backhoe equipped with a front ' loader pushed the excavated soil into a stockpile adjacent to the north end of the excavation The excavation was continued until the bottom sheet of black plastic was exposed and removed, thus, removing the soil material as required by Mr. Collins. The measured depth from the top of the paved surface to the bottom of the excavation was approximately 12 feet. The excavator proceeded digging in the northward direction until all desired soil material was removed from the excavation and stockpiled. The final excavation dimensions were 110 feet long, 15 feet wide ' and 12 feet deep On June 15, 1993 Mr. Collins arrived at the site at approximately 9:00 am. Mr. Collins inspected the excavation and determined that no additional excavation was required. 2.3 Soil Transportation and Disposal On June 15 and 16, 1993 a total of 360 cubic yards of soil material was loaded onto 20 end dump trucks with the excavator, and transported to the Forward Class III Landfill in Stockton, ' California under non-hazardous waste manifests. The total volume of soil was calculated based on the number of end dump truck loads at 18 cubic yards per load ' 2.4 Excavation Backfilling Procedures Backfilling procedures began on June 16, 1993. The excavation was backfilled with a clean pea ' gravel to one foot below the top of the paved surface. The backfilling procedures were observed by personnel of BSK & Associates Geotechnical Engineers (BSK). No compaction effort is required for clean pea gravel, thus, this portion of the backfilling did not require compaction tests A total of 640 tons of pea gravel was placed into the excavation. ' On June 17, 1993 ditches were excavated in the pea gravel to re-route the two inch schedule 40 PVC water line removed prior to excavation procedures and the storm drain line that was removed during tank removal procedures in January 1992. The pipe lines were re-routed and buried at their original depths. The pea gravel was graded and compacted at the surface 07121cd2 7