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tasted below reportinq limits. Refer- to Table III for a summary of <br /> bath tests. <br /> PLUME SIZE AND CONFIGURATION: <br /> The writer did not witness the removal of the tanE , when at was <br /> noted that there was some discoloration to the soil . During the <br /> re-e cavation operation , no visable discoloration or free product <br /> was noted; there was a gasoline ©dor present , but is wa; not <br /> possible to determine the e:cact location of those odors. Above a <br /> depth of about 10 ' , the odor was more pronounced; below that depth <br /> it became fainter and fainter , with the strongest odor towards the <br /> south side of the e<cavation. The character of the sediments <br /> encountered did not indicate any distinct cones or lavers of high <br /> permeability , and no free product was observed during the spoil <br /> removal , although as mentioned earlier , some was noted in selected <br /> samples. <br /> ESTIMATE OF AMOUNT OF PRODUCT LEAF AGE: <br /> There are no records available to indicate the amount of leakage, if <br /> any, during the years the tans~ was in service. Because the tank <br /> integrity was confirmed just prior to removal , it is assumed that <br /> any product leakage occurred either in the product lane to the pump <br /> island , (which was determined to be leaking during the test , ) or <br /> adjacent to the pump island. <br /> CONCLUSIONS. <br /> 1 . All of the samples from the excavation tested clean for both <br /> Ethylene Dibr-omide and organic lead. <br /> ^. Only one sample, SW--2W, had detectable levels of TPH-G. <br /> 71. An analysis of the LUFT manual procedures for estimating <br /> contamination levets that can be left in place without threatening <br /> ground water reveal that only two components in the bottom samples <br /> slightly e,ceed the limits derived from Table 2w-1 of that manual ; <br /> Toluene and Xylene in sample D-CS. All other components fall below <br /> the limits; (E,-hibit k . ) <br /> 4. The sail type, Stockton Adobe Clay, has a low Storie Inde < , and <br /> imperfect drainage; it appears unliFely that vertical or horizontal <br /> fluid migration through such a medium would be very e;,tensive. <br /> a. Additional spoil removal and sampling is necessary from the west <br /> end of the site. <br /> RECOMMENDATIONS: <br /> The writer is in agreement, with the enclosed letter from Mr. Vosi-es <br /> of Normac Inc. , proposing additional spoil removal from the <br /> J <br />