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Fall 2019 Subsidence and Geologic Field Observations <br /> Southern Panels Mining Area <br /> 4.6 Traverse F-F <br /> Traverse F-F' departs Traverse E-E'in a southeasterly direction over the east end of mined E-seam <br /> Longwall Panels E5,E6,E7,and E8. Most of the MVB pads on the eastern end of mined Longwall <br /> Panel E5 and E6 have been reclaimed with the exception of MVB E64. This traverse allows <br /> access to MVBs E7-1/2, E7-3, and E74 over mined E-seam Longwall Panel E7 and to MVB pads <br /> E8-1, E8-2, E8-3, and E84 over mined E-seam Longwall Panel E8 (See Map 1). The E-seam <br /> overburden depth along this traverse is from 1,000 feet to more than 1,200 feet. <br /> During our spring 2019 field visit, subsidence-related features were observed on MVB E8-1 and <br /> E8-3 pads. Differential settlement cracks were observed on MVB E8-2,E8-3, and E84 pads. Fall <br /> 2019 field visit observations found that the subsidence crack previously observed on the MVB E8- <br /> 1 pad had healed and could not be relocated. This may have been in part due to the removal of the <br /> ventilation pump and trailer, which reworked the surface materials on the pad near the well head. <br /> The two subsidence cracks on the pad of MVB E8-3 were present during our fall 2019 field visit <br /> along with differential settlement cracks along the road at the southwest corner of the pad. These <br /> features are discussed in more detail below as Location 7. Differential settlement cracks on the <br /> MVB E84 pad were still present as of our fall 2019 field visit and somewhat exacerbated by the <br /> mining activities in the area. These features are discussed in more detail below as Location 8. <br /> 4.6.1 Location 7 <br /> A pair of subsidence cracks were observed during our spring 2019 field work on the north side of <br /> the MVB E8-3 pad (Figure 15) where the pad contained very little fill material. Recent longwall <br /> mining had occurred beneath the area at the time. Both cracks had maximum dimensions of 4 <br /> inches in width and depth. The longest of the two cracks measured approximately 15 feet. The <br /> E-seam overburden thickness at this location is approximately 1,000 feet. <br /> Observations of this same location during our fall 2019 field visit found it hard to locate the two <br /> subsidence cracks primarily due to activities on the pad associated with the removal of the pump <br /> and trailer (Figure 16). Numerous differential settlement cracks were observed along the south <br /> side of the road leaving the southwest side of the pad. This road connects this pad with the MVB <br /> E84 pad. These cracks were observed where the greatest fill placement had occurred during <br /> 831-032.910 Wright Water Engineers, Inc. Page 24 <br /> February 2020 <br />