ARCHIVED REPORTS LIMITED SOIL ASSESSMENT AND TEST PIT EXPLORATION

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t1l KLEINFELDER topographical expression (fill areas above adjacent ground surface) the estimated extent of the fill is illustrated on Plate 2 and could extend an average of 940 feet by 140 feet wide. Please note however the areas beyond TP12 to the north and TP9 to the south have not been evaluated, therefore the extent of debris in these directions and other areas of the site remains unknown. The eastern extent of the fill against and/or below the western race track stands is also unknown east of TP1 . and the TP9 and TP12 and an assumed be 3) Assuming the fell does not extend y average fill depth of 15 feet the estimated removal volume would be approximately 61 ,000 cubic yards. Based on extrapolated dimensions in Plate 2, and an assumed fill depth of 15 feet the removal volume may be approximately 91 ,000 cubic yards. 4) The analytical findings in the AST, Dry Well and interior Race Track Area were overall unremarkable with the exception of arsenic detected at depth in two locations adjacent to two dry wells. The arsenic values (5.91 to 13.8 mg/kg) while exceeding residential PRGs and OEHHA health risk values based on Kleinfelder's experience with arsenic in the central valley are not atypical of background values. Please note however the evaluation in the Dry Well Area was conducted to evaluate potential leaching of contaminants at depth adjacent to the dry wells. Therefore, naturally occurring arsenic may be near the surface at values exceeding PRGS and OEHHA health risk numbers. 5) Based on the metal results in the debris area and the discussion in Section 6.1.3 the debris area is not suitable for the proposed residential development. Assuming future development of this area Kleinfelder recommends evaluating the extent of debris, further characterization for disposal purposes and removal to an approved disposal facility. Since evidence of building materials was found associated with the debris piles, the potential exists for said building materials to contain asbestos. If evidence of building materials is discovered to contain friable asbestos, this material would be classifed as a hazardous asbestos waste with disposal to a Class I landfill accepting asbestos waste materials. At least one soil sample with a total lead value of 1610 mg/kg indicates a hazardous waste classification for disposal purposes. Two of the composite samples also had lead values of 556 and 821 mg/kg, exceeding criteria of 350 mg/kg, which indicates disposal at a Class I disposal site (Hazardous Waste Disposal Facility) per Section 25157.8 of the California Health and Safety Code (CH&SC). While r there are some variances under Section 25157.8, they do not appear to apply to the site. Please also note that elevated total lead values as detected in the debris area will often fail the STLC criteria of 5 mg/l for classification as a hazardous waste for disposal purposes. 6) Significant cut and fill areas have been noted at the site. Although Kleinfelder has evaluated a large fill area west of the stands, other areas have not been evaluated for debris. Therefore additional debris could be encountered in future grading and development of the site. In the event debris, unusual odors or soil 58671.E02/ST05R1127/DH:ly Page 19 of 22 ©2005 Kleinfelder, Inc. September 15, 2005