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Fall 2012 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mining Areas <br />Observations noted along Traverse K -K' included healing and sealing of a deeply incised rut <br />(first observed in spring 2012) between the MDW E3 -36 and E3 -40 pads (Location 1) and <br />healing and sealing of subsidence - related cracking along the east side of the access road to MDE <br />E3 -32.5 (Location 2). <br />In addition, seven shorter traverses that originate from Traverse K -K' were visited as part of the <br />fall 2012 observations (i.e., Kl -Kl', K2 -K2', K3 -K3'. K4 -K4', K5 -K5', K6 -K6', and K7 -K7'). <br />Traverse K I -K 1' is above both mined and unmined portions of E -Seam Longwall Panels E3 and <br />E4 (Map 2). Subsidence effects noted along this traverse during the spring 2012 field visit were <br />again observed and described in this report as Locations 3 and 4. Traverses K2 -K2', K3 -K3', <br />K4- K4'and K7 -K7' are above mined portions of E -seam Longwall Panel El, E2 and E3 (Map 2). <br />No subsidence related observations were noted along these traverses during the fall 2012 field <br />visit. Traverse K5 -K5' is above unmined portions of E -seam Longwall Panel E5 which will not <br />be mined for at least another year. Traverse K6 -K6' is above the eastern ends of unmined E- <br />seam Longwall Panels E4 and E5 as well as above mined portions of E -seam Longwall Panel E3 <br />(Map 2). No subsidence - related features were observed during the fall 2012 field visit for that <br />portion of this traverse above mine E -seam Longwall Panel E3. A more detailed discussion of <br />Traverse K 1- K1' can be found later in Sections 3.5. <br />3.4.1 Photographic Observation Point 12 <br />This photographic comparison location was established in 2009 along the Dry Fork immediately <br />downstream of its confluence with the Horse Gulch drainage (Map 2). This location established <br />a view looking northeastward over the western end of E -seam Longwall Panel El where several <br />vertical sandstone stacks could be observed standing above the surrounding vegetation. These <br />stacks represented readily observable features that could be visually monitored while longwall <br />mining occurred beneath this area. Overburden thickness above the E -seam in the vicinity of the <br />stacks is approximately 1,000 feet. <br />Photographic comparisons find that there has been no observed changes at this location since the <br />spring 2010 field visit (i.e., after longwall mining passed beneath the area). <br />831 - 032.794 <br />April 2013 <br />Wright Water Engineers, Inc. Page 8 <br />