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ATTACHMENT C SECOR INTERNATIONAL INCORPORATED FIELD AND LABORATORY PROCEDURES STANDARD PROCEDURE FOR HOLLOW STEM AUGER DRILLING Prior to drilling,the boring locations are marked with white paint or other discernible marking and cleared for underground utilities through USA. In addition,the first five feet of each borehole are drilled with a hand auger, posthole digger, or air/water knife to evaluate the presence of underground structures or utilities. Once predrilling efforts to identify subsurface structures are complete, precleaned hollow stem augers(typically 8 to 10 inches in diameter)are advanced using a rotary drill rig for the purpose of collecting samples and evaluating subsurface conditions. Upon completion of drilling and sampling the augers are retracted and the borehole is either completed as a well or filled with concrete, bentonite grout, hydrated bentonite chips or pellets as required by the regulatory agency. In areas where the borehole penetrates asphalt or concrete, the borehole is capped with an equivalent thickness of asphalt or concrete patch to match finish grade. During the drilling process, a physical description of the encountered soil characteristics (i.e. moisture content, consistency, odor, color, etc.), drilling difficulty and soil type as a function of depth are described on boring logs. The soil cuttings are classified in accordance with the Unified Soil Classification System (USCS). Soil cuttings are temporarily stored on-site in 55-gallon DOT-approved drums pending waste profiling and proper disposal. A label is affixed to the drums indicating the contents of the drum, suspected contaminants, date of drilling, borehole number, and depth interval from which the contents were generated. STANDARD PROCEDURE FOR SOIL SAMPLING - SPLIT SPOON SAMPLING The precleaned split spoon sampler lined with three 6-inch long brass or stainless steel tubes is driven 18 inches into the underlying soils at the desired sample depth interval. The sampler is driven by repeatedly dropping a 140-pound hammer a free fall distance of 30 inches. The number of blows (blow count) to advance the sampler for each six-inch drive length are recorded on the field logs. Once the sampler is driven the full 18-inch drive length or the sampler has met refusal (typically 50 blows per six inches), the sampler is retrieved. Of the three sample tubes, the bottom sample is generally selected for laboratory analysis. The sample is carefully packaged for chemical analysis by capping each end of the sample with a Teflon sheet followed by a tight-fitting plastic cap and sealing the cap with non-volatile organic compound (VOC), self-adhering silicon tape. A label is affixed to the sample indicating the `