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Fall 2018 Subsidence and Geologic Field Observations <br /> Southern Panels Mining Areas <br /> �i. <br /> I. <br /> a <br /> Figure 1. Southwestward view during our fall 2018 field visit of two of five <br /> subsidence cracks observed for the first time on the road near the E7-12 MVB pad. <br /> Longwall mining had recently passed beneath this area at the time of our field visit. <br /> 4.3.2 Location 2 <br /> Two parallel subsidence cracks were newly observed approximately 300 feet south of the E7-12 <br /> MVB pad during our fall 2018 field work. These cracks have a N60°W orientation and are offset <br /> by 13 feet but their varied edge features suggest that they were not formed at the same time. The <br /> southern crack has very sharp edges with maximum dimensions of 7 inches in width, 5 inches in <br /> depth, and a continuous length of about 27 feet. The northern crack has more rounded edges from <br /> vehicle traffic and has a maximum width of 0.5 inches on the side of the road. This northern crack <br /> also has a 6-inch vertical offset with the highest side toward the southern crack (see Figure 1). <br /> Longwall mining had recently passed beneath this area where the E-Seam overburden thickness is <br /> about 800 feet. <br /> 831-032.900 Wright Water Engineers, Inc. Page 14 <br /> April 2019 <br />