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KEI-P88-1013 .R2 July 15, 1992 Page 2 extraction wells) and ten monitoring wells were installed by Kleinfelder and Associates , as shown on the attached Site Plan, Figure 3 . These soil borings and wells apparently delineated the zone of soil contamination that was then present at the site. Since soil boring data are included in previous Kleinfelder reports and in our previously submitted work plans for this site, this information will not be repeated in this report. The extent of ground water contamination at the site, however, has not yet been completely defined. On January 19, 1988 , and again on July 26, 1988 , Kaprealian Engineering, Inc. (KEI) submitted proposals for soil and ground water remediation at the site. A proposal was subsequently approved by Unocal and the pertinent regulatory agencies. Soil remediation began on September 19 , 1988, and was completed on December 12 , 1988 . The area excavated in relationship to the Kleinfelder and Associates soil borings is as indicated on the attached Site Plan, Figure 3 . A total of 28 soil samples were collected and analyzed from the excavation sidewalls and bottom. These samples were used to further delineate the zone of contamina- tion and guide soil excavation. The excavation was terminated at ground water (a depth of 53 feet) or at a shallower depth if pit bottom sample analyses indicated no detectable contaminant concentration. Soil was excavated to a maximum depth of 53 feet (the existing shallow water table depth) . During excavation, two monitoring wells (MW1 and MW7) and all seven vapor extraction wells were destroyed. Also during excavation, six of the remaining seven monitoring wells (MW2 , MW3 , MW4 , MWS, MW8 , and MW9) suffered various amounts of wellhead damage. The complete results of the soil excavation pro3ect are presented in KEI 's report (KEI-P88- 1013) dated December 15, 1988 , and are not repeated here. As previously stated, during the excavation activities it was necessary to destroy two monitoring wells, MW1 and MW7 . The wells were destroyed on September 25, 1988 , after permits were obtained from the San Joaquin County Public Health Services (SJCPHS) . KEI concluded that both the source of the contamination and the majority of the contaminated soil had been removed from the site, and that it was necessary to determine the extent of ground water contamination. It was also concluded that KEI would prepare proposals, as necessary, for well repair and abandonment, installa- tion of additional monitoring wells, and subsequent ground water remediation (if warranted) . On November 29 , 1988 , an attempt was made to sample the existing wells. Unfortunately, most of the wellheads were damaged during soil excavation. Wells MW2 , MW3 , MW4 , MW5, and MW9 were in need of