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,00k\ I . GR Field Methods and Procedures Updated June 16, 1999 results recorded as reconnaissance data. GR does not consider field screening techniques to be verification of the presence or absence of hydrocarbons. Well Abandonment Prior to well abandonment, the total depth of the well and the depth-to-water in the well casing are measured and recorded. Groundwater monitoring wells are abandoned by filling the well casing with neat cement using a tremie pipe and pump. The tremie is removed and the cement in the well casing is pressurized to approximately 10 pounds per square inch (psi) for approximately 2 minutes. The well box is removed and the upper 5 feet of well casing is drilled out. The boring is then backfilled with neat cement or native material, depending on local regulations. Well Destruction Prior to well destruction, the total depth of the well and the depth-to-water in the well casing are measured and recorded. Groundwater monitoring wells are destroyed by drilling the well boring out to remove the casing, sandpack, and seal material. The boring is advanced at least one foot past the installed depth of the well to insure that all the casing and seal material are removed. Upon completion of drilling, the boring is backfilled to ground surface with neat cement placed using a tremie pipe and pump. Storing and Sampline of Drill Cuttings Drill cuttings are stockpiled on and covered with plastic sheeting or stored in drums depending on site conditions and regulatory requirements. Stockpile samples are collected and analyzed for disposal classification on the basis of one composite sample per 100 cubic yards of soil. Stockpile samples are composed of four discrete soil samples, each collected from an arbitrary location on the stockpile. The four discrete samples are then composited in the laboratory prior to analysis. Each discrete stockpile sample is collected by removing the upper 3 to 6 inches of soil, and then driving the stainless steel or brass sample tube into the stockpiled material with a hand, mallet, or drive sampler. The sample tubes are then covered on both ends with teflon sheeting or aluminum foil, capped, labeled, and placed in a cooler with blue ice for preservation. A chain-of-custody form is initiated in the field and accompanies the selected soil samples to the analytical laboratory. Stockpiled soils are covered with plastic sheeting after completion of sampling. A-2