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Fall 2018 Subsidence and Geologic Field Observations <br /> Southern Panels Mining Areas <br /> valley. Subsidence features observed during our 2017 field visits have become very difficult to <br /> identify, especially if one was not aware that they had previously existed. As a result,there are no <br /> discussions or photographs associated with these locations included in this report. <br /> A series of five parallel subsidence cracks were observed in the road near, and on the pad of, the <br /> E7-12 MVB pad. They are the result of longwall mining that occurred recently beneath the area. <br /> This location has been given the designation Location 1 for the purpose of this report and is <br /> discussed in more detail below. <br /> Approximately 300 feet south of the E7-12 MVB pad, there are an additional two parallel <br /> subsidence cracks that cross the road in a N60°W orientation. These cracks are discussed below <br /> as Location 2. <br /> Lastly, the elevation offset associated with a subsidence crack in the road leading to MVB E6-14 <br /> pad (originally observed in spring 2017) is still present and has not been removed by regrading. <br /> However, continued vehicle traffic on this road has lessened the abrupt change in the road. Other <br /> subsidence cracks observed on, or near, the MVB E6-14 pad further north have become more <br /> obscured with time. <br /> 4.3.1 Location 1 <br /> A series of five parallel subsidence cracks were newly observed at the north end of the E7-12 MVB <br /> pad and along the nearby road during our fall 2018 field visit. These cracks are spaced between <br /> 15 and 50 feet apart and have an orientation between N35°E and N70°E. Longwall mining had <br /> recently passed beneath this area where the E-Seam overburden thickness is approximately 800 <br /> feet. Several of these cracks had sharp edges suggesting relatively recent development. The <br /> maximum dimensions for these cracks were 2 inches in width, 6 inches in depth, and a length <br /> represented by the width of the road (about 25 feet). Figure 1 shows two of the cracks looking <br /> southwest. <br /> 831-032.900 Wright Water Engineers, Inc. Page 13 <br /> April 2019 <br />