ARCHIVED REPORTS LIMITED SOIL ASSESSMENT AND TEST PIT EXPLORATION

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i 4 KLEINFELDER 1 EXECUTIVE SUMMARY Legacy Development contacted Kleinfelder for the purpose of evaluating potential l environmental concerns associated with the Stockton 99 Speedway prior to residential development by conducting a Phase II Assessment concurrent with a Phase I Assessment (ESA). This report represents the Phase II Assessment. Legacy Development agreed on evaluating four areas of concern based on a preliminary site visit including a reported Debris Area, Track Area, Dry Well Area and Above Ground Storage Tank (AST) area. On July 1, 5and 7 2005 Kleinfelder collected a total of 33 soil samples in these four areas Twenty two of the 33 soil samples were analyzed for various analytical suites tand analytes including metals, petroleum constituents, volatile organic compounds and semi-volatile organic compounds. Sampling methodology included hand augering, pushprobe borings and utilization of a backhoe for test pit exploration. Hand auger sampling was conducted in the interior track area and pushprobe borings were advanced adjacent to the dry wells and AST area. A brief summary of Kleinfelder's findings are as follows: • Based on test pit observations, an area of approximately 600 by 140 feet located west of the race track area was noted as containing fill material. Based upon test pit findings and surface topographical expression (fill areas above adjacent ground surface) the estimated extent of the fill could extend an average of 140 feet wide by 940 feet long. In general, the debris appeared to be building demolition material. The primary fill material was concrete, followed by asphalt and wood with trace amounts of miscellaneous items including; bricks, tire, hoses, sheet metal parts, wire, plastic, burnt wood, aggregate rock, concrete tile, glass etc. • Based on the test pit (TP) findings, the vertical extent of the fill has not been defined beyond 15 feet in depth in the majority of the debris area assessed (See Plate 2). The lateral extent has also not been fully defined. The areas beyond Test Pit (TP12) to the north, beyond TP9 to the south and east of TP1, have not been evaluated. Therefore the extent of debris in these directions is unknown. Removal volume based on a fairly known area (600 by 140 feet) is estimated at 61,000 cubic yards and is extrapolated (900' x 140') to be up to 91,000 cubic yards assuming an average 15 foot depth of fill material. • 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 at values which in Kleinfelder's opinion are not atypical of background arsenic concentrations in the Central Valley. 58671.E02/ST05R1127/DH:ly Page 1 of 22 ©2005 Kleinfelder, Inc. September 15, 2005