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R (D Flock Logic <br />Consulting LLC <br />Memorandum <br />Date: 23 June 2008 <br />To: Collin Stewart <br />Ry Stone <br />Bill Bear <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 />From: Brad Lindsay <br />Subject: Spring 2008 Subsidence Crack Mapping <br />Field Survey <br />A detailed field survey above the B4, B5, B6, and B7 longwall areas was conducted. Roadways in <br />these areas were walked or driven over slowly to observe subsidence cracks. Areas between and <br />around roadways were hiked. A cursory field survey along roadways above the B8, B9, B 10, and <br />B11 longwall areas was conducted. The surveys were completed in May and June 2008. Each new <br />crack was photographed and the orientation, length, width, and vertical displacement were measured. <br />Observations <br />The large slide on the south slope at the bottom of Freeman Gulch has continued to move. In addition <br />to the rock fall from the upper cliffs, the lower portion of the slope is sliding downhill to the <br />northeast. As a result, a portion of the Freeman Gulch road has been moved downhill approximately <br />20 feet. Cracks in the immediate vicinity of the slide were not measured. Smaller slides continue to <br />occur along the roadways in Freeman Gulch and Sheep Corral Gulch. No new cracks were observed <br />above the B4 - B7 longwall panels. No cracks were observed above the B8 - B 11 longwall panels. <br />The attached map outlines areas that were walked or driven. <br />Most of the B4, B5, and B6 mining areas lay below Freeman Gulch. Much of this area is covered <br />with thick vegetation making it difficult to see any cracks that may exist. It is also difficult to estimate <br />the total length of cracks that cross the road and continue into the thick brush. , <br />Files <br />Crack measurements and field notes are recorded in an Excel file (Subsidence Crack Mapping Spring <br />08.xls). The AutoCAD map (Subsidence-Crack-June08-source.dwg) was updated with the lengths, <br />orientations, and locations of new cracks observed and areas surveyed. Digital photos are attached.