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permits maximum allowable in-place limits for B/T/X/E of .3/.3/1/1 <br /> mg/kg, (ppm.) A review of the laboratory analysis, (Table III,) <br /> reveals that only the sample at 30' in bore hole ##2 exceeded those <br /> limits. <br /> ENVIRONMENTAL FATE WORKSHEETS <br /> In order to further define allowable levels, Table 2-4 of the LOFT <br /> Manual was utilized. Although only the samples from bore hole #2 <br /> exceeded allowable levels using Table 2-1, a worksheeL for each <br /> detected substance was run to confirm those results. Tables VI-1 <br /> through VI-10 show the results of that analysis, which reveals that <br /> all samFlns except one are below indicated cleanup levels. The <br /> amount of Benzene measured at a0' in bore hole #2, (0.405 ppm,) <br /> slightly exceeds the allowable limit indicated an the worksheet. <br /> However, core samples from 35' & 40' in the same hole were below <br /> reporting limits (.005 ppm,) for this, and all other tested <br /> ingredients. <br /> CONCLUSIONS <br /> 1. Only .3 cores out of 44 analyzed had detectable levels of tested <br /> substances. <br /> 2. Geologic correlations between the S auger holes were quite good; <br /> uniformity of the beds is apparent. <br /> 3. The coarse sand & gravel bed present in the bottom S to 10 ;eet <br /> of all auger holes was thoroughly sampled; ( twice in HH #2, a times <br /> in the rest,, ) and all tested substances were below detection limits. <br /> 4. All contamination was located in, or in close proximity to, a <br /> layer of sticky blue-gray clay as shown on Plates VII & VIII. <br /> 5. The very low level of contamination is immobilized in a clay <br /> which has extremely low permeability, and appears to be an effective <br /> barrier to further vertical and horizontal migration of the trapped <br /> chemicals. A review of the drillers log of the City of Stockton <br /> well #22, (Exhibit D,) reveals that the interval from the surface to <br /> 156' was logged as blue clay, with no sands recorded. No <br /> contamination has been noted in water samples analyzed from that <br /> well , indicating that the minor amount of residual contamination at <br /> the site appears to be effectively immobilized. <br /> RECOMMENDATIONS <br /> Because of the low levels of c�jt;tamination, and the immobilization <br /> of those substances in a thick clay of law permeability, the future <br /> 4 <br />