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u KEI-P88-1013 .R4 October 27 , 1994 Page 6 Figure 1) were installed at the site. The four wells were each drilled and completed to total depths ranging from 70 to 72 . 5 feet below grade. Ground water was encountered at depths ranging from 64 to 69 feet beneath the surface during drilling. The four new wells (MW10 through MW13) were developed on June 2 , 1992 , and were initially sampled on June 3 , 1992 . Existing monitoring well (MW6) was not sampled because it was dry on the days the four new wells were developed and sampled (June 2 and 3 , 1992 , respectively) . On April 9 and 13 , 1992, four monitoring wells and a recovery well previously installed by other consultants (wells designated as W1, W2 , MW2 , MW8 , and RW1 on the attached Figure 3) were destroyed at the sub3ect site by pressure grouting each well from the bottom of the well to the surface . Four other wells (designated as W3 through W5, and W9 , on the attached Figure 3) could not be precisely located and thus were not destroyed. An attempt was made to locate these four wells by geophysical methods (ground-penetrat- ing 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 Figure 3 ) are apparently obscured by the building and the footings of associated structures presently occupying the subject site. Water samples from wells MW10 through MW13 , and selected soil samples from the borings of MW10, Mwll, and MW12 , were analyzed at Sequoia Analytical Laboratory in Concord, California. The samples were analyzed for TPH as gasoline, BTEX, 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 results of the soil analyses are summarized in Table 5, and the results of the water analyses are summarized in Table 3 . Based upon the analytical results for the ground water samples collected from wells MW10 through MW13 on June 3 , 1992 , KEI recommended the implementation of a monitoring and sampling program at the site. Documentation of the well installation procedures, sampling techniques, and the analytical results are presented in KEI ' s report (KEI-P88-1013 .R2) dated July 15 , 1992 . RECENT FIELD ACTIVITIES - MONITORING WELL INSTALLATION On July 13 and 14 , 1994, two additional two-inch diameter monitor- ing wells (designated as MW14 and MW15 on the attached Figure 1) were installed at the site. The wells were each drilled, con- structed, and completed in accordance with the guidelines of the Regional Water Quality Control Board (RWQCB) and the California