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• Suomental Site Investigation Scoping Document Pittman Elementary School,Stockton,California January 23,2004 Page 6 concern at the site and provide definition for future removal action. Sample locations and the number of samples are subject to adjustment based on field observations and laboratory analytical results. 3.1 LAWN AREA Additional soil samples will be collected from around two PEA sample locations to characterize the extent of contamination from organochlorine pesticides (OCPs). The collection of additional samples to evaluate elevated cobalt concentrations has not been included, as it is Condor's opinion that the cancer risk associated with cobalt is a manageable risk. Organochlorine Pesticides Soil samples will be collected from a total of 10 locations in the lawn area on the western and southern portions of the site and analyzed for OCPs by EPA Method 8081A. The two PEA locations, L9 and L15, will be resampled. In addition, soil samples will be collected from four SSI sample locations surrounding each PEA sample location, approximately five feet away from the original PEA sample location. The proposed SSI sample locations are indicated on Figure 8,Appendix A. Soil samples will be collected at each location from 0 to 6 inches and 2.0 to 2.5 feet bgs. Samples will be collected at the surface by loosening the soil with a stainless steel shovel. A stainless steel spoon will be used to place the loose soil into laboratory-supplied glass jars. The deeper subsurface samples will be collected at each sample location by using a stainless steel hand auger and transferring the soil directly from the hand auger into laboratory-supplied glass jars. Each jar will be labeled for sample identification and placed in a cooler chilled with ice. Prior to use at each soil sample location, all sampling equipment will be decontaminated in the field by washing with a solution of laboratory-grade, non-phosphate detergent and deionized water and then double-rinsed. Following soil sample collection, an equipment blank sample will be collected by running deionized water through the sampling equipment and collecting the rinsate water in appropriate sample containers. The equipment blank sample will be analyzed for the same constituents as the samples collected with the field equipment. Second discrete surface and subsurface soil samples will be collected from one randomly selected sample location for quality assurance/quality control. This sample will not be identifiable as a second sample to the laboratories. The second samples will be prepared in an identical manner and analyzed for the same analytes as their primary counterparts. The general sample locations, sample types, and associated analyses are listed in Table 3 below. The laboratory analytical methods, detection limits, and associated United States Environmental Protection Agency(USEPA)Region D{Preliminary Remediation Goal (PRG) values are presented in Appendix C. Table 3—Proposed SSI Sampling Pro ram awn Area Sam le Locations Depths Number of Sam les Matrix Analyses Method 10 locations 5 locations per PEA 0-0.5 and 2-2.5 feet 10 shallow,10 soil Organochlorine pesticides 8081A location bgs intermediate(hold) 1 second sample 1 location 0-0.5 and 2-2.5 feet I shallow,I soil Organochlorine pesticides 8081A location bgs intermediate(hold) Equipmentblank water water Organochlorine pesticides 8081A 3.2 STRUCTURE DRIPLINES Additional soil samples will be collected from locations near PEA sample locations with detected lead concentrations exceeding the DTSC-provided value of 200 mg/kg: P1, P7, P8, P9, P10, Pll, P20/P21 (1 location), P27, P34, P73, and P75. Samples will be collected from locations approximately two feet away ow %k �, CONDOR