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October, 1994, groundwater began to seep into the excavation at about 15 ' bgl , this correlated well with water levels encountered during removal of the UST' s Groundwater was encountered at about 10 ' below grade during the placement of the soil borings & monitoring wells in August, 1995 After development & purging of the wells on August 9, 1995, the water table was measured at an average depth of 7 95 ' below grade PRIOR USE OF UST' S The tanks were used to fuel company and personal vehicles for business purposes They were installed in June, 1974, and were taken out of service in June, 1994, when they were removed. There are no accurate records concerning fuel usage, and inven- tory tracking reconcilliation was not performed LOCATION OF NEARBY WELLS There are no known monitoring wells within the zone of influence A California Water Service well is located across Fremont Street to the south • BRIEF REVIEW OF PRIOR WORK June 8, 1994 - Thorpe Oil Co removed two (2) 1, 000 gallon UST' s which had been used for storing & dispensing unleaded gasoline There was a strong petroleum odor noted during excavation & removal of the tanks, and apparent somal discoloration The piping from the tanks to the dispensing pump was removed, as well as the pump No odors or discoloration were noted in those areas The removal of the tanks was witnessed by Pamela Violett of the San Joaquin County EHD Soil samples were taken from the backhoe bucket by an employee of Geo-Analytical laboratory, as directed by the County representative PLATE III shows the locations of those samples The results of the laboratory analyzes are listed on TABLE I The removed spoil was returned to the hole, and barricades were placed around the site Correspondence from the San Joaquin Co EHD, dated July 18, 1994, required further assessment work to evaluate possible soil & water contamination As a result of that correspondence, a workplan was prepared by WJH to remove the returned soil & as much additional contamination as possible October 21, 1994 - Approximately 128 cubic yards of contaminated soil was removed from the site of the removed UST' s, resulting in an excavation about 16 ' x 18 ' x 16 ' deep Soil samples taken from the sides & bottom all revealed detectable amounts of BTEX & TPH-G, refer to PLATE IV for details The results of the 3 I I