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KEI-P89-1104 .R9 . December 17 , 1992 Page 6 Federal Environmental Protection Agency. A separate technical report describing these field operations will be submitted in the near future. During the initial phase of the septic tank removal operations (on July 15 , 1992 , as noted above) a seven-inch, steel-cased, domestic water well was encountered about 40 feet southwest of monitoring well MW1 . On August 5 , 1992 , a representative of KEI was on-site during a downhole video camera survey of this well. The survey was conducted by Water Well Technology, Inc. of Rancho Cordova , California. The downhole camera survey indicated that the total depth of the well is 78 feet below grade and that the casing extends to 72 feet below grade. Possible perforations in the casing were observed starting at 42 feet below grade. Based on our previous research at the California Department of Water Resources for the other domestic well on-site (which was destroyed on January 24 , 1992) , the well was probably installed prior to 1951 . A water sample was collected from the second domestic well on August 21, 1992 . Prior to sampling, the well was purged of four casing volumes of water by the use of a submersible pump. The water sample from the domestic well was analyzed at Sequoia Analytical Laboratory in Concord, California. The sample was analyzed for TPH as gasoline by EPA method 5030/modified 8015 , and BTX&E by EPA method 8020 . In addition, the sample was analyzed for EPA method 8010 constituents The analytical results of the water sample collected from the domestic well indicated 300 ppb of TPH as gasoline, 21 ppb of xylenes , 1 . 3 ppb of 1, 4-dichlorobenzene, and 4 . 8 ppb of 1, 2-dichlorobenzene, with all other analyzed constitu- ents showing non-detectable concentrations. The results of the water sample analyses are summarized in Table 10 . A copy of the laboratory analysis and the Chain of Custody documentation are attached to this report. On September 24 , 1992 , the second domestic well was pressure grouted to the surface with bentonite cement grout by the use of a tremie pipe in conjunction with a grout pump. The second phase of the destruction of this well will include drilling around the well casing (by the use of oversized hollow-stem augers) to the full depth of the well (approximately 78 feet deep) , and grouting the annulus with neat cement grout to the surface. This second stage of well destruction is planned to be completed following station demolition in 1993 . RECENT FIELD ACTIVITIES - EXPLORATORY BORINGS Per Unocal Corporation ' s procedure for potential site divestment locations, on November 9 and 10, 1992 , seven exploratory borings