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0 �! Appendix A Trenches will be excavated at the Former Teepee Burner Structure. Trenche will be excavated to five feet bgs with a backhoe. Temporary shoring or sidewall sloping will not be i tecessary. Soil encountered in the trenches will be lithologically logged using ASTM Method D2433-93 md standard geologic techniques. Soil removed from the trenches will be placed on plastic sheetin 7 or a paved surface. Shallow soil samples(less than 5 feet bgs)will be collected from the trenche using a hand-held drive sampler attached to an extended handle or Encore''M sampler(where applicable). Soil samples may also be collected directly from the backhoe bucket. A1.2.3 Water Samples Two types of water samples,including groundwater and surface water sampl s will be collected during the AM&C field investigation. Description of the sample types and proced es for collection of the surface and shallow ground water samples are described below. A1.2.3.1 Groundwater Sampling Grab groundwater samples will be collected using a direct push sampling rig Once the targeted sampling depth is reached,the drive pipe will be pulled upward to allow groundwater o flow into the drive pipe. Samples will be collected by lowering a disposable,bottom-emptying bailer ilown the drive pipe, carefully raising the bailer,then decanting water from the bailer to the appropriate containers. The grab groundwater sample may also be collected using a peristaltic pump and silicone tubing. Samples collected for dissolved metals analysis will be field-filtered through a 0.45 micron in-line filter. The direct push drilling method is described below. Direct push drilling will be used,to advance and sample,grab groundwater om three borings at the site. Using a direct push drill rig,the borings are advanced and samples collected for lithology by hydraulically pushing or driving stainless steel core samplers to targeted sample depths. The core samplers are generally lined with clear plastic liners up to 5 feet long. After advancing the sampler to the targeted depth,the core samplers are pulled out of the borehole,split apart,aid the soil-filled core liner removed. Minimal soil cuttings are generated using this method. Following groundwater sample collection,the temporary borehole will be backfilled with hydrated bentonite. Surface restoration will consist of manually patching the borehole with soil,asphalt,or concrete to ir.arch existing conditions. A1.2.3.2 Surface Water Sampling Surface water samples will be collected from two storm water ponds located at the site. Surface water sampling will be performed by field personnel,equipped with appropriate legth waders.Field personnel will carefully walk to the approximate center of the ponds, taking care to mi imize their movements so as not to disturb the underlying sediment prior to collection of surface water samples. The surface water samples will be collected by dipping a one-liter,unpreserved amber bottle just below the surface of the water until the bottle is filled. Once the bottle is filled,the water will be dec ted into sample bottles appropriate to each analyses provided by the analytical laboratory. A1.2.4 Sediment Sampling Sediment samples will be collected from three storm water ponds located at 1he site. Sediment sampling will be performed by field personnel,equipped with appropriate length waders. Field personnel will carefully walk to the pre-determined sampling locations within the ponds,t#ng care ti minimize their movement so as not to disturb the sediment prior to sampling. Sediment saniples will be collected with a tube sampler or hand push corer. The cylinder of the sampler is manually pressed into sediment at the bottom of the pond. Any entrained water will b poured off from the top of the sampler,using care not to KB61125 APPENDIX A MACTEC Engineering and Consulting, Inc. A4 September 28,2005