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Spring 2013 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas (E -Seam) <br />Figure 6. Spring 2013 image looking northeast at <br />one of several small subsidence cracks in the <br />eastern portion of the E4 -1/2/3 MDW pad. <br />4.6.2 Location 5 <br />Figure 7. Spring 2013 looking northeast along <br />the eastern edge of the same pad at subsidence <br />cracks along the crest of the containment berm. <br />Differential settlement is a factor in the <br />development of these cracks given the large <br />amount of fill placed in this area. <br />An approximately 500 -foot long access road leads to the MDW E4 -4 pad where it departs the road <br />to the MDW E3 -64/65 pad. About 100 feet south of this intersection, a discontinuous 35 -foot long <br />subsidence crack was observed near the eastern edge of the road leading toward the MDW E4 -4 <br />pad (Figure 8). This location is above the northern edge of the headgate entries of mined E -seam <br />Longwall Panel E3. The maximum observed crack width and depth were 0.5 and 2 inches, <br />respectively. The E -seam overburden depth at this location is approximately 1,000 feet. <br />831 - 032.795 Wright Water Engineers, Inc. Page 17 <br />September 2013 <br />