ARCHIVED REPORTS LIMITED SOIL ASSESSMENT AND TEST PIT EXPLORATION

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KLEINFELDER 6.1.3. Debris Area Each of the LUFT five metals including cadmium, chromium, lead ne discrete a soil sample zinc were also detected from the five stockpile composite samples an collected at a depth of 15 feet in Test Pit TP2 (See Table 1). Three of these metals including cadmium, chromium and lead and were found in one or more soil samples which exceeded the Residential PRGs and OEHHA health risk values. Cadmium was detected in two composite soil samples (TP1 and TP12) and one discrete soil sample (TP2-15') at concentrations ranging from 2.08 s°detected7.55 ginghe oneddgcretethe Oampe cancer risk value of 1.7 mg/kg. Chromium w (TP2-15') at 255 mg/kg, exceeding the Residential PRG of 210 mg/kg. Total lead was detected in all six soil samples in the debris areas at concentrations ranging from 273 to 1610 mg/kg also exceeding the PRGs and OEHHA health risk values of 150 mg/kg. Total lead detected at 1610 mg/kg in the discrete soil sample 1 (TP2 ')-15is over the TTLC classification for hazardous waste for disposal purposes. ) also had lead s of Two of the composite samples (TP1 and TPh2ndicates disposalaatea Class6 disposal 821 mg/kg, exceeding criteria of 350 mg/kg, wh site (Hazardous Waste Disposal Facility) perdisposal osal pulposes STLC lead valun 25157. of the California es and Safety Code (CH&SC). Please note that for p 1 will also have to be obtained, which evaluates the potential for lead to leach from soil in a acidic environment (such as a landfill). If lead for disposal hat 5 purposesl.o Add tlonal more the soil will also be classified as a hazardous waste ' sampling and analyses should be expected for soil profiling prior to disposal. 6.2 CONCLUSIONS AND RECOMMENDATIONS Based upon our findings we have formulated the following conclusions and recommendations: 1) Based on our sampling and analyses conducted from test pit observations an area of approximately 600 by 140 feet (areas between TP9 and TP12 and the approximate width between the western debris area (TP5) area and TP1 was noted as containing fill material. Fill detected test pits atthe themaximum expl ed depths depth of 15 feet and was detected in all the ranging from 7 to 15 feet. The bottom of the fill was detected at approximately 6 feet in Test Pit TP5 along the western border of the site. 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 re ate rock, concrete tile, glass etc. For details refer to Table 4. 2) Based on the test pit findings the vertical extent of the fill has not been defined beyond 15 feet in depth in the majority of the debris area assessed. The lateral extent has also not been fully defined. Based upon test pit findings and surface 1Page 18 of 22 58671.E02/ST05R1127/DH:ly September 15, 2005 ,112105 Kleinfelder, Inc.