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• Page 5 Center, located across Robinhood Drive from the former Unocal site, appeared to have, at one time, contained underground storage tanks An inspection of this site revealed areas of concrete and asphalt disturbances that appeared to be the locations of former pump islands and underground storage tanks However, no record of any subsurface investigation work performed on this site was found in the SJCPHS files The locations of all of the sites discussed in this paragraph are shown on the attached Adjacent Sites Location Map, Figure 6 On April 8 , May 20 and 21, 1992 , four additional two-inch diameter monitoring wells (designated as MW10 through MW13 on the attached 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 subject site by pressure grouting each well from the bottom of the well to the surface Four other wells (designated as W3 through W5 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-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 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 , MW11, and MW12 , were analyzed at Seyuuid ArnalyLival LabULdLUly in C.UIlf-OLd, CallfOlil-La The samples were analyzed for TPH as gasoline, STEX, 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 KEI-POS-1013 APA