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~ Flock j_ogic <br />• consulting LLC <br />Memorandum <br />Date: 13 November 2006 <br />To: Collin Stewart <br />Ry Stone <br />Bill Bear <br />From: Brad Lindsay <br />Rock Logic Consulting <br />PO Box 544 . Cedaredge, CO 81413 <br />Phone: (435) 851-9044 • rocklogicconsulting@gmail.com <br />Brad Lindsay • Consulting Geologist <br />Subject: Fa112006 Subsidence Crack Mapping <br />Field Survev <br />A detailed Feld survey was conducted above the B1, B2, and B3 longwall areas on <br />November 3, 2006 through November 11, 2006. Roadways in these areas were walked or <br />driven over slowly to observe subsidence cracks. Areas between and beyond the roads were <br />also hiked. Each new crack was photographed and the orientation, length, width, and vertical <br />displacement were measured. <br />Observations <br />The majority of cracks identified in the 2004 and 2005 surveys has healed or continue to <br />heal. Many of these cracks are no longer visible. New cracks were observed over the B2 and <br />B3 longwall areas. No new cracks were observed over the B 1 longwall area. The area above <br />the northwest comer of the B 1 panel was hiked from the TC-03-03 drill pad. The area is a <br />steep slope. No apparent evidence of cracking or subsidence was observed. As has been <br />observed in previous surveys, the majority of cracks appear at topographic high points. Five <br />new cracks or series of cracks were identified and mapped. The majority of the new cracks <br />identified were found along the northeast edge of the B3 panel. <br />Files <br />Crack measurements and field notes are recorded in an Excel file (Subsidence Crack <br />Mapping.xls). The AutoCAD map (Subsidence-Crack-Nov06-source.dwg) was updated with <br />the lengths, orientations, and locations of new cracks observed and areas surveyed. Digital <br />photos of most of the cracks are attached. <br />M2-1 <br />