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(nominal outside diameter) hollow-stem augers to approximately 12 feet <br /> bgs or to first encountered groundwater. A core barrel sampler will be <br /> inserted within the hollow stem of the lead auger to provide a continuous <br /> core of each 5-foot interval. Each cored section will be examined and <br /> logged by an ERM geologist,under the supervision of a California <br /> Professional Geologist. Each boring will be logged in accordance with <br /> American Society for Testing and Materials Method D 2488 for the visual <br /> description of soils. Soil samples will be subjected to field measurements <br /> made with a photoionization detector (PID),which measures ionized <br /> volatile organic vapors and gives a direct readout in parts per million by <br /> volume in air. <br /> Soil samples will be collected continuously from each boring using a core <br /> barrel sampler to approximately 12 feet bgs or the depth of first <br /> encountered groundwater. Soil samples will be inspected to determine <br /> the physical condition of the subsurface materials. <br /> Two soil samples from each boring will be submitted to a California- <br /> certified laboratory (as presented on Table 1) for the following analyses: <br /> • Bulk density by ASTM D 2937, <br /> • Porosity; <br /> • Water content by ASTM D 2216; <br /> • Grain size distribution by ASTM D 422; and <br /> • Soils description by ASTM D 4318. <br /> • One sample of a cohesive soil from each boring will be submitted for <br /> analysis of permeability by ASTM D-5084. <br /> 4.3 GROUNDWATER MONITORING WELL INSTALLATION <br /> PROCEDURES <br /> As presented on Figure 5,monitoring wells will be constructed of 2-inch <br /> inside diameter,Schedule 40 polyvinyl chloride (PVC) casing. <br /> Approximately 5 feet of slotted (0.020-inch factory cut) 2-inch PVC well <br /> screen will be installed from the bottom of the boring to approximately 2 <br /> feet above the water table as measured during the time of drilling. The <br /> remaining portion of the well will consist of 2-inch PVC blank casing. The <br /> artificial filter pack will consist of a 1C sand or equivalent. The sand will <br /> be added until there is approximately four vertical feet of sand <br /> surrounding the well screen. At this time,the augers will be extracted at <br /> 1-to 2-foot intervals that will allow the sand to flow outward,between the <br /> PVC well screen and the boring wall. This process will continue until a <br /> sand pack has been placed approximately 1 to 2 feet above the slotted <br /> ERM 8 LFSCO,INC/0%737M-N.. ]IIW <br />