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~ INTRODUCTION <br />~' ;M. <br />• On December 14"', 1998 a 2"d geo-technical drilling project was initiated at the <br />Oxbow underground coal mine at Somerset, Colorado. This drilling project was <br />to provide bedrock and water level information along the proposed Elk Creek <br />slope entry. This entry is to access the D-seam, located approximately 240 <br />stratigraphic feet above the B-seam currently under development by Oxbow <br />Coal's Sanborn Creek entry. <br />D.A. Smith Drilling of Loma, Colorado was contracted to undertake the core <br />drilling. Glenn E. Miller Inc. of Elizabeth Colorado was contracted to administer <br />the drilling and to geotechnically log the core samples. <br />A series of top to bottom geotechnical cores and piezometer wells were to be <br />constructed along a projected entry path into the D-seam. Particular attention <br />was to be made of the soil-bedrock interface at each drill site. <br />Field operations were completed on January 8th, 1999 with the demobilization of <br />the Smith Drilling Company drill rig. <br />DRILL COSTS & PRODUCTIVITY <br />A total of 7 drill sites were completed during the project and a total of 717 feet <br />were drilled. Of this footage, 247 feet were cored. Overall core recovery was <br />238 feet or 96.4°k (Section 2). The invoice costs for the dolling were $26,243.24 <br />and took 10 operational days to complete. This was a productivity rate of 72 feet <br />per operational day. The invoice cost was $36.60 per dot foot. The individual <br />day sheets for the project are located in Section 5. <br />CORE HANDLING PROCEDURES <br />The priority of the recent coong project was to collect core data, rock mechanic <br />and hydrologic information from the D-seam horizons in the proposed Elk Creek <br />slope entry. <br />Continuous coring was the drilling method selected by Oxbow. Core samples <br />would allow the direct observation of all strata above, through and below the D- <br />seam. If requested, rock mechanic and chemical samples would be selected <br />from the core sequences Gosest to the coal seam. <br />Each core run was measured for recovery and received a core sheet description <br />of its lithology and relative rock strength. Rock and coal materials "selected for <br />preservation were measured, placed in plastic sleeves, stapled and sealed in <br />cardboard core boxes. These core boxes are stored at the Oxbow Mine facilities. <br />(• <br />Page 1 of 3 <br />