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sampling locations are paired with soil gas sampling locations. One geotechnical soil sample will be collected from each of the following areas: former drum storage area, former Foundry sand area,former trash burning cage area, and between the former Warehouse and Main Factory Building. Four geotechnical soil samples will be collected from the former pond areas. Sample locations may change in the field based on the locations of the highest soil gas concentrations, as well as lithology and moisture. 5.4.2. Proposed Sampling Media and Analyses Dudek proposes to collect soil vapor samples for VOC analysis by EPA Method 8260B (DTSC 2012). Soil vapor samples will be collected in accordance with the 2012 DTSC Advisory-Active Soil Gas Investigations (DTSC, 2012). Soil gas samples will be analyzed on site by a California Department of Health Services (DHS)certified mobile laboratory. Dudek proposes to collect soil samples from the soil cores retrieved during installation of the soil gas points.The samples will be analyzed for VOCs by EPA Method 8260B (prepared via EPA Method 5035A), SVOCs by EPA Method 8270C, Title 22 metals by EPA Method 6010Bn471A, and hexavalent chromium by EPA Method 7199. The soil samples from the former trash burning area, and to the east and southeast, will also be analyzed for dioxins and furans by EPA Method 8280A or 1613B. Soil samples from Pond 1 will also be analyzed for pH by EPA Method 9045C. Geotechnical samples will be analyzed for total organic carbon (TOC), fraction organic carbon,bulk density, grain density,porosity, soil moisture content, effective permeability, and soil classification (grain size and Atterberg limits). Methods recommended in Appendix H of DTSC's Guidance For The Evaluation and Mitigation of Subsurface Vapor Intrusion To Indoor Air(October 2011) will be followed. Soil samples will be analyzed by California Department of Health Service (DHS) certified stationary laboratories. 5.4.3. Proposed Sampling Depths The target depths for soil gas samples are within the interval from 5 feet bgs to 40 feet bgs, the bottom of which is approximately the top of capillary fringe. Sample locations are identified on Figure 2. Of the 30 soil gas sampling locations, 11 will include vapor samples at approximately five depths. The precise sample depths will be selected in the field based on lithology but are anticipated at approximately 5, 10, 20, 30, and 40 ft. bgs. The DTSC has requested soil gas samples from "at the soil cover/buried debris interface" and"immediately below the fill/cover" within the sampling locations at the former ponds. These depths are approximately between 4—6 feet bgs and 6— 10 feet bgs, respectively, but will be more precisely determined in the field. Following installation and sampling of the 11 multi-depth soil gas points, 19 soil gas points will be installed and Soil Gas and Soil Sampling Work Plan—Rev.4 7693-05 Former Keamey-KPF Facility Dudek Stockton,CA 12 September 2013