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[~ Dock Logic <br />Consulting LLC <br />Memorandum <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 />Date: 13 October 2007 <br />To: Collin Stewart <br /> Ry Stone <br /> Bill Bear <br />From: Brad Lindsay <br />Subject: Spring 2007 Subsidence Crack Mapping <br />Field Survey <br />A detailed field survey above the B4, B5, B6, and B7 longwall areas was conducted in <br />September 2007. Roadways in these areas were walked or driven over slowly to observe <br />subsidence cracks. Areas between and around roadways were hiked. Each new crack was <br />photographed and the orientation, length, width, and vertical displacement were measured. <br />Observations <br />A large slide has occurred on the south slope at the bottom of Freeman Gulch. Many cracks <br />were observed in the vicinity of the slide (above the east end of the B6 longwall panel). <br />Fewer cracks were observed in the flats above the west end of the B4 - B7 longwall panels). <br />Some mud drying cracks were observed above the west end of the BS and B6 panels. <br />Most of the B4, B5, and B6 mining areas lay below Freeman Gulch. Much of this area is <br />covered with thick vegetation making it difficult to see any cracks that may exist. It is also <br />difficult to estimate the total length of cracks that cross the road and continue into the thick <br />brush. <br />Files <br />Crack measurements and field notes are recorded in an Excel file (Subsidence Crack <br />Mapping Fa1107.x1s). The AutoCAD map (Subsidence-Crack-Sept07-source.dwg) was <br />updated with the lengths, orientations, and locations of new cracks observed and areas <br />surveyed. Digital photos of the cracks are attached. <br />[7 <br />M2-1 <br />