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A Rock Logic <br />Onsulting LLC <br />Memorandum <br />Date: 24 November 2014 <br />To: Jim Abshire <br />Bill Bear <br />Art Etter <br />Kendra Hinton <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: Fall 2014 Subsidence Crack Mapping <br />Field Survey <br />A thorough field survey above the B -15 and west end of B -16 longwall areas was conducted on <br />November 20d' through 22nd 2014. The western end of the B -15 panel was checked in the spring of <br />2014. The B -15 and B -16 panels run parallel in an east west direction underlying and running east of <br />Stevens Gulch Road. Areas of flat terrain, mildly sloping and moderately steep topography overlie <br />the panels. Traverses over the panel were hiked to observe visual evidence of subsidence. Thick oak <br />brush covers some of the area. Some areas were covered by several inches of snow and other areas <br />had dry ground. A GPS unit was utilized in track mode to record the path of all traverses and <br />locations of cracks observed. Each new crack was to be photographed and the orientation, <br />length, width, and vertical displacement were measured. No cracks were observed in this <br />investigation. <br />Observations <br />No cracks were observed during this survey despite extensive hiking. No cracks were observed over <br />the west end of the B -15 panel last spring. Some areas that were surveyed were covered by several <br />inches of snow which could hide small cracks. Large cracks would still have been observed. The <br />areas with snow will be resurveyed in the spring. <br />Files <br />Crack measurements and field notes are recorded in an Excel file (Subsidence Crack Mapping Fall <br />14.xls). The AutoCAD map ( Subsidence - Crack- Novl4- source.dwg) was updated with the GPS track. <br />Digital photos of the area are attached. <br />