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��� .raaax <br /> 3.1.2 Collecting Drill.Cuttings <br /> The field geologist/engineer may observe drill cuttings from the drilling fluid return for <br /> lithologic information to supplement discrete sampling. Sampling and logging cuttings will be <br /> performed as follows: <br /> 1. The height of the drilling table above ground surface, lengths of the drill bit, sub and <br /> drill collars, and length of drill rods should be taken into account in calculating the <br /> depth of penetration. <br /> 2. In mud rotary drilling, a small-diameter, fine mesh hand screen will be used to obtain <br /> a sample of the cuttings from the borings by holding the screen directly in the flow <br /> of the drill fluid return line. In air rotary drilling, cuttings will be collected after <br /> discharge from the cyclone. <br /> 3. In rotary drilling, a composite sample may be obtained from the return line by <br /> leaving the screen in place during the time it takes the driller to advance the boring to <br /> a preselected depth. <br /> 4. In rotary drilling, the travel time for cuttings to reach the surface may be estimated <br /> each time the driller adds a new length of drill rod by timing the first arrival of <br /> cuttings after circulation is resumed. This travel time can be used along with the <br /> depth of penetration to estimate the start and finish of each 5-foot sampling interval. <br /> 3.2 LOGGING OF EXPLORATORY BORINGS <br /> The observations of the field geologist/engineer will be recorded on a BORING LOG OR WELL <br /> LOG at the time of drilling. The drill rig operator and the field geologist/engineer will discuss <br /> significant changes in material penetrated, drilling conditions, hydraulic pressure, drilling action, <br /> and drilling fluid circulation rate. The field geologist/engineer will be present during drilling of <br /> soil borings and will observe and record such changes by time and depth. <br /> Drill cuttings and core samples will be observed in the field. A lithologic description will be <br /> recorded on the BORING LOG using the Unified Soil Classification System(LJSCS) as <br /> described in the American Society of Testing and Materials (ASTM) Standard D 2488-90. This <br /> description will include the USCS soil type, grain sizes and estimated percentages of each, . <br /> moisture content, color according to the Munsell color charts (Kollmorgen Instruments Corp.), <br /> plasticity for fine-grained materials, consistency, and other pertinent information, such as degree <br /> DRILLING AND DESTRUCTION OF SOIL BORINGS Page 4 of 6 <br /> PROTO-DD.doc REVISTONDATE!MARCH 1996 DD-4 <br />