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Spring 2016 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mininq Areas <br />This traverse is located above the E -South Mains and the western ends of mined E -seam Longwall <br />Panels E3, E4, and E5, as well as unmined E -seam Longwall Panel E6. Previous observations of <br />subsidence cracks were described on the MVB E5-20 pad beginning in the Fall 2015 Subsidence <br />Report. Details associated with the observed subsidence cracks associated with this location are <br />provided below as Location 1. <br />No other subsidence -related features were observed along this traverse during our spring 2016 <br />field visit. <br />4.2.1 Location 1 <br />The first observation of subsidence features on the MVB E5-20 pad occurred during our fall 2015 <br />field visit (approximately one month after longwall mining passed beneath this area). <br />Observations made during the fall 2015 visit found four large, parallel subsidence cracks oriented <br />in a N5°W direction with a spacing of between approximately 10 and 40 feet from each other. The <br />first of these cracks was located on the access road approximately 30 feet east of the pad. The <br />second and third cracks are located where the access road joined the pad (see Figure 1). At that <br />time, the maximum length of the western crack was a nearly continuous 135 feet, with the crack <br />ending on barren ground north of the pad. This pad was noted to have a maximum width of 14 <br />inches and maximum depth of about 6 feet. The E -seam overburden depth at this location is 450 <br />feet. <br />Observations at the MVB E5-10 pad during the spring 2016 field visit found continued evidence <br />of the subsidence cracks but with evidence of weathering such as rounded crack edges and <br />sediment infilling. Figure 2 shows the same subsidence cracks represented in Figure 1 as observed <br />during our spring 2016 field visit. Some widening of the cracks (up to 3 feet) was noted in response <br />to edge deterioration and slumping into the openings. However, crack depth was diminished <br />(about 2 feet) and the overall continuity of the longest crack was disrupted. <br />831-032.798 Wright Water Engineers, Inc. Page 10 <br />August 2016 <br />