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SUPPLEMENTAL SITE INVESTIGATION WORK PLAN <br /> South Pointe Property <br /> Stockton, California <br /> Scope of Work <br /> 4.3.3 DTSC Approval and Notifications <br /> Prior to implementing field activities, work approval shall be obtained from DTSC, either in the <br /> form of a Work Plan approval letter, or via written email communication. Stantec will coordinate <br /> with DTSC for posting and/or distribution of any required public notices regarding the project. <br /> 4.3.4 Permitting <br /> Stantec will obtain a borehole permit from San Joaquin County Department of Environmental <br /> Health, and coordinate with the agency for field inspection as required. <br /> 4.4 SOIL AND GROUNDWATER SAMPLING <br /> Stantec will subcontract with a California-licensed driller to facilitate the collection of soil and <br /> grab groundwater samples as described in the following sections. Soil samples will be collected <br /> from multiple depth intervals at locations across the site as summarized in Tables 1 and 2 and <br /> illustrated on Figure 7. Four of the boreholes will be extended to first-encountered groundwater <br /> for collection of a grab groundwater sample and analyzed in accordance with Table 3. Soil and <br /> groundwater sampling activities are described in the following sections. <br /> 4.4.1 Soil Sampling <br /> Temporary boreholes will be advanced to 5 feet bgs using a hand auger, and then advanced <br /> to terminal depth using direct-push equipment. From 5 feet to total depth, the boreholes will be <br /> cored continuously with subsurface materials retrieved in clear plastic liners. Subsurface <br /> materials will be logged and described for lithologic characteristics using the Unified Soil <br /> Classification System and screened for visual/olfactory characteristics and for the presence of <br /> VOCs using a photoionization detector (PID) equipped with a 10.6 electron-volt lamp. Soil <br /> classification, visual/olfactory observations of soil conditions, and PID results will be documented <br /> in the project notebook or on field data sheets. Collected samples will be placed into <br /> laboratory-supplied containers for shipment to the analytical laboratory. Samples will be labeled <br /> with a unique sample ID, and sample ID and collection time will be logged onto a chain of <br /> custody form. <br /> 4.4.2 Groundwater Sampling <br /> Four of the temporary boreholes will be advanced to first-encountered groundwater, <br /> anticipated at a depth of approximately 10 to 20 ft bgs. Although the sampling program does <br /> not call for analysis of samples between 9 feet below street grade and first-encountered <br /> groundwater, subsurface materials will be continuously logged as described above. The <br /> borehole will be advanced approximately 4 feet into first encountered groundwater. A <br /> temporary polyvinyl chloride (PVC) well screen will be inserted into the borehole, and <br /> groundwater samples will be removed from the borehole using a dedicated, disposable plastic <br /> bailer. Laboratory-supplied glassware will be filled directly from the bailer, and care will be taken <br /> 4.4 <br />