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Fall 2018 Subsidence and Geologic Field Observations <br /> Southern Panels Mining Areas <br /> consequence being a significant drop (up to 3 feet) of the outer edge of the pad coincident with the <br /> previously-observed differential settlement cracks. Evidence of this elevation change on the outer <br /> edge of the pad was still present during our fall 2018 site visit. <br /> Other previously-observed smaller subsidence cracks in the access road south of the MVB E6-12 <br /> remain as small elevation changes in the road that are inconsistent with water bar construction. E- <br /> seam overburden in this area is about 800 feet. <br /> Further south, Traverse D-D crosses the mined portion of E-seam Longwall Panel ET <br /> Approximately 115 feet south of the gate near the E7-l 0 MVB pad,two parallel subsidence cracks <br /> were observed in the road and will be described below as Location 3. Subsidence features were <br /> also observed during the fall 2018 field visit on three of the four MVB pads accessible from this <br /> traverse. The subsidence features associated with MVB pads E7-10 (Location 4), E7-9 (Location <br /> 5), and E7-8 (Location 6) will be discussed in more detail below. MVB pad E7-11 had no <br /> observable subsidence features during the spring and fall field visits. <br /> 4.4.1 Location 3 <br /> Two parallel subsidence cracks (offset by about 20 feet) were observed for the first time during <br /> our fall 2018 field visit. These cracks are located about 115 feet south of the gate near E7-10 MVB <br /> pad and have a bearing of about N10°W. Observations show that these cracks have been healed <br /> somewhat by vehicle traffic and grazing cattle (see Figures 3 and 4). The northern of the two <br /> cracks does not extend beyond the road while the southern crack extends about 30 feet south of <br /> the road before being lost in vegetation. The maximum dimensions of these two cracks is 6 inches <br /> in width, 4 inches in depth, and about 45 feet in length. The E-seam overburden depth at this <br /> location is approximately 1,000 feet. <br /> 831-032.900 Wright Water Engineers, Inc. Page 16 <br /> April 2019 <br />