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1 r <br /> ATTACHMENT B <br /> FIELD AND LABORATORY PROCEDURES j <br /> 1 � <br /> Exploratory Drilling <br /> The soil borings will" be drilled using 8-inch hollow-stem auger drilling equipment. <br /> Borings will be logged by an IT geologist or engineer using the Unified Soil Classification <br /> System and standard geologic techniques. Soil samples will be collected at 5-foot depth <br /> intervals using a California-modified split-spoon sampler. The sampler will be driven a <br /> maximum of 18 inches using a 140-pound hammer with a 30-inch drop. All soil samples <br /> f for chemical analysis will be retained in brass liners, capped with Teflon squares and <br /> plastic end caps, and sealed in Ziplock"I-style bags. The samples will be placed on ice for <br /> transport to the laboratory accompanied by chain-of-custody documentation. All down- <br /> hole drilling and sampling equipment will be steam-cleaned following the completion of <br /> t the soil boring. Down-hole sampling equipment will be washed in a trisodium phosphate <br /> f or alconox solution between samples. a <br /> r C <br /> Groundwater Monitoring Well Installation <br /> Groundwater monitoring wells will be completed in five'soil borings by installing 2-inch <br /> diameter, flush-threaded, Schedule 40 PVC casing with 0.020-inch factory-slotted screen. <br /> R Approximately 20 feet of screen will be placed in the bottom of the boring. An RMC 2112 <br /> sand pack, or equivalent, will be placed in the annular space across the entire screened <br />++' interval, and will extend approximately 2 feet above the top of the screen for the well. A <br /> E 2 to 3 foot bentonite transition seal will be placed atop the sand. pack, and a Portland <br /> cement seal will extend from the bentonite transition seal to the ground surface. The <br /> Portland cement seal will be emplaced by tremie pipe or through the center of the hollow- <br /> stem augers in one continuous operation from the bottom of the interval to be filled to the <br /> top. Emplacement of the Portland cement grout specifically shall not be accomplished by <br />{ "free fall" from the ground surface. The boring.logs will show well construction details. <br /> The groundwater monitoring wells will be developed after completion. The development <br /> procedure for each well will consist of pumping or bailing water from the well until the <br />} water is visibly clear, the well goes dry, or until a maximum of ten casing volumes have <br /> been removed. <br /> 911-011.1 Blworkplan B-1 <br />