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KEI-P88-1013 .R2 July 15, 1992 Page 7 The wells were sampled on June 3 , 1992 . Existing monitoring well (MW6) could not be sounded or sampled because it was dry on the days the four new wells were developed and sampled (June 2 and 3 , 1992 , respectively) . Prior to sampling, the wells were checked for the depth to the water table and the presence of free product and sheen. No free product or sheen was noted in any of the wells. After the monitoring data were collected, between 6 . 5 to 7 . 5 gallons of water were purged from each well, and water samples were then collected by the use of a clean Teflon bailer. Samples were decanted into clean VOA vials that were then sealed with Teflon- lined screw caps and stored in a cooler, on ice, until delivery to a state-certified laboratory. RECENT FIELD ACTIVITIES - MONITORING WELL DESTRUCTION On April 9 and 13 , 1992 , four monitoring wells and a recovery well previously installed by other consultants (wells designated as W1, W2 , MW2 , MWS, and RW1 on the attached Site Plan, Figure 2) were destroyed at the subject site by pressure grouting each well up the casing to 1 foot below grade. Four other wells (designated as W3 . through W5, and W9, on the attached Site Plan, Figure 2) could not be precisely located and thus were not destroyed. An attempt was made to locate these four wells by geophysical methods (ground- penetrating radar) , but this procedure was not successful in pinpointing the exact position of these wells. Three other wells (designated as MW3 through MW5 on the attached Site Plan, Figure 2) are apparently obscured by the building and the footings of associated structures presently occupying the subject site. ANALYTICAL RESULTS Water samples from wells MW10 through MW13 , and selected soil samples from the borings of MW10, MW11, and MW12 , were analyzed at Sequoia Analytical Laboratory in Concord, California. All samples analyzed were accompanied by properly executed Chain of Custody documentation. The samples were analyzed for TPH as gasoline by EPA method 5030/modified 8015, BTX&E by EPA method 8020, and for EPA method 8010 constituents. In addition, the water samples collected from MW11 and MW12 were analyzed for nitrates and fecal coliform bacteria. The concentrations of TPH as gasoline and benzene detected in the ground water samples collected from monitoring wells MW10 through MW13 on June 3 , 1992 , are shown on the attached Site Plan, Figure la. The results of the soil analyses are summarized in Table 3 , and the results of the water analyses are summarized in Table 2 . . Copies of the laboratory analyses and Chain of Custody documenta- tion are attached to this report.