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GeosynteCD consultants 3.2 Field Prouam In order to adequately assess the presence of residual COCs beneath the former pond ' areas with respect to lateral and vertical extent,two angled borings will be completed at the starting locations shown on Figure 2. Soil and groundwater samples collected from these borings will provide information regarding potential residual COCs beneath the ' former ponds. Details of this plan are provided in the following sections. 3.2.1 Drilling Angled Borings The borings will be advanced using hollow stem augers. The borings will begin at a minimum of 4 feet from the edge of the caps and will be advanced at the approximate angle listed on Table i and shown on Figure 3. These angles were selected for optimal coverage based on the size and shape of the former ponds and their respective caps. The augers will be advanced to the target intervals specified in Table 1 and a split-spoon sampler will be driven past the target interval to collect the sample. At each boring, soil samples will be collected at a minimum of every 10 vertical feet from ground surface to the groundwater table, in order to obtain a vertical profile of soil concentrations along the boring. One grab groundwater sample will be collected just below the depth where ' the water table is first encountered at each boring. A photoionization detector (PID) will be used to screen soil and monitor the worker breathing zone area per HASP guidelines. Boring locations at each pond are shown on Figures 4 and 5. Details for ' sampling at the designated intervals are described below. 3.2.2 Soil Sampling ' Samples will be collected at each sample depth and location, using the following protocol: Once the target depth(i.e., 10, 20,30 vertical ft bgs, etc.) is reached, the split- spoon sampler, containing three 6-inch brass tubes, will be driven approximately 18 inches past the target depth. Table 1 provides a list of the proposed samples along with sample information, such as sample vertical depths, sample locations along the borings, and laboratory analyses. Soil samples will be collected using the following protocol: 1. Depending upon recovery in the sampler, the top 6-inch brass tube will be ' collected as the soil sample for carbamate and urea pesticides, fumigants, Work Plan_Stockton Pond Inv_01-07-08 8 01.0708