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Phase II Sampling and Analysis Plan SOP-2—Drilling and Sampling Port of Stockton-Rail and Bridge,Stockton,CA FN the leading edge of the rod string. As the drive rod is advanced into the subsurface, the cutting shoe shears a 1.125-inch OD soil core which is collected in a clear plastic liner inside the drive rod. HSA drilling will be used for borings terminating at 3 ft bgs. HSA drilling allows for drilling and casing a borehole simultaneously, thereby eliminating cave-in problems and contamination of soil samples from units above. Borehole advancement will be conducted using a single auger flight advanced to no more than 3 ft bgs. If refusal is met prematurely, due to the presence of a boulder, landfill waste, etc., then the hole will be offset and attempted again. Soils from the retracted auger flights will be placed on a thick plastic sheet in piles corresponding to the depth interval, and sampled accordingly. 6.2.3.2 Soil Description Soils will generally be described in accordance with the 1990 ASTM D-2488-90, Standard Practice for Description and Identification of Soils (Visual-Manual Procedure). Descriptive information to be recorded in the field will include: • Identification of the predominant particle size and range of particle sizes • Percent of gravel, sand, fines, or all three • Description of grading and sorting of coarse particles • Particle angularity and shape • Maximum particle size or dimension The plasticity of fines description will include: • Color using Munsell Color System • Moisture (dry, wet, or moist) • Consistency of fine-grained soils • Structure of consolidated materials • Cementation (weak, moderate, or strong) The USCS group symbols will be used for identification. Additional information to be recorded includes: depth to the water table, caving or sloughing of the borehole, changes in drilling rate, depths of laboratory sample collection, presence of organic materials, presence of fractures or voids in consolidated materials, and other noteworthy observations or conditions, such as the locations of geologic boundaries. 6.2.3.3 PID Screening At 1-foot intervals within the soil cores, the soil will be screened with a PID. The soil will be screened using the following procedure: • From the sampling location within the soil core, use a tool to create a void. • Insert the tip of the PID into the void and allow the measurement to stabilize. • Record the highest PID reading on the boring log. 2-8