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The borehole was drilled by a local drillirq contractor using a Central Mining Equipment ICME) <br />model 55 drip rig. A 4•inch solid auger was used to drill through the colluvium/alluvium <br />material. Two Standard Penetration Test ISPT) drives were taken within this material using <br />standard American Society for Testing and Materials (ASTM) methods, including a 2•inch <br />outside diameter (O.D.) split spoon sampler and 140 pound (Ib1 drop hammer. <br />Appendix A shows the kq for this borehole. The drilling conflmisd collwiumlallirvium depths <br />of appro>amately 18 feet. The material classified as a silty sand with laboratory anayses on <br />material taken from split•spoom samples. Maximum particle size was 1.5 inches. The contact <br />with competent Rollins Sandstone bedrock is at 18 feet. The hole was continued to 75 feet <br />to confirm sandstone bedrock continuity. Grilling within the competent sandstone was <br />performed using a 4-inch rotary tricone bit. Water was used to circulate cuttings to the <br />ground suHace where they were logged. Since the groundwater depth could not be <br />determined because of the use of water in the drilling process, a 1.5-indt diameter piezometar <br />was installed with screen in the bottom 50 teat. Several weeks later, the water IevN within <br />the piezometer was at 50 feet bebw the ground surface. This roading may, however, reflex <br />drilling water. <br />~I A geobgic strata that was not encountered in the drilling program was shale within the Bowie <br />Member. This shale strata is located between the sandstone outcrops above the site (also part <br />of the Bowie Member) and the Rollins Sandstone below. Operations of the Sanborn Creek <br />Mine take data within this shah, and is believed to be located below the surficial collirvium, <br />topographicaNy between the vertical Bowie Member sandstone Jiffs above and the Roll'urs <br />Member sandstone outcrops at the railroad tracks below. A geobgic cross section is <br />presented on Drawing 95255-02. Shab strata located within the Bowls Member is described <br />as 'grey shah with thin to thick lenticular beds of buff sandstone, and contains several coal <br />beds' (PBR, 19951. <br />~~ <br />88266/1424.RPT God Mi~w W~~a Bank Ougn far tM Sanborn Crest M(rr <br />Oetobar taea WESTEC, Inc. 4 <br />