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APPENDIX B FIELD PROCEDURES The general procedures used in site assessments for drilling exploratory borings, collecting samples, and installing monitoring wells are described in this appendix. These general procedures are used to provide consistent and reproducible results; however, conditions may exist where variations of these procedures are applicable. A California state-registered geologist supervised the following procedures. SOIL SAMPLING Borings were completed using continuous push technology (CPT) equipment. Soil samples for logging were obtained at five-foot intervals by advancing a modified California split-spoon sampler equipped with. stainless steel liners into undisturbed soil beyond the tip of the boring rods. Soils were logged by a Pinnacle geologist or engineer according to the Unified Soil Classification System and standard geological techniques. Exploratory soil borings were backfilled to the surface with a bentonite-cement slurry pumped into the boring through the CPT rods. At the completion of the borings, the rods were removed and steam cleaned. Rinsate was collected in a DOT rated 55-gallon drum. A concrete surface seal or asphalt patch was placed at ground surface to match existing conditions. HYDROPUNCH SAMPLING Groundwater samples were collected in the first encountered water bearing zone (approximately 55 feet bgs) and at 80 feet bgs using HydroPunch sampling equipment. The sampler was advanced to the target depth using CPT rods. The sampler was opened approximately 2 to 3 feet by pulling back the rods to expose the sample screen and bailer was lowered through the centers of the rods to collect the groundwater samples. After samples were collected, the sampling equipment was decontaminated and the boreholes were sealed as described above. CP\C:1Archive\Arco121861Reports12186p106.doc B-1