2020-06-25_REVISION - C1981035 (14)

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WORST POSSIBLE CONSEQUENCES OF SUBSIDENCE The two track road following the ridge line west of the project area is the main structure on permitted or adjacent lands which could suffer damage due to the effects of subsidence. In the event that a surface subsidence crack were to intersect the road, it is possible that some repair of the road would be required to allow its continued use. This road is used primarily by the surface grazing lease holders of the State of Colorado land for access to cattle rangelands in the north part of Section 36. Where subsidence cracks have intersected two track roads above the existing King I Mine, repairs were made by shoveling less than a pickup truck load of"road base" into the crack. In the event that subsidence cracks damage any barbed wire fence within the permit area (a fencepost could be dislodged or strands of barbed wire could stretch and break or sag), GCC Energy, LLC will repair said fences without charge to the surface grazing lease holder, or will reimburse the lease holder for any repairs necessary. The buildings and structures on and around the surface facility area of the mine will not be damaged by subsidence because there are no minable coal seams beneath this area. Addition of PR-1 O Parcels (Federal Coal Lease COC-78825) PR-10 adds acreage to the PAP that was studied under the Environmental Assessment and Technical Resources Reports performed jointly by the Bureau of Land Management and the Office of Surface Mining, Reclamation and Enforcement for the Dunn Ranch Lease by Application area (coal lease COC-78825). Please see Appendix 15; Dunn Ranch LBA Area Environmental Assessment, Section 3.4.3.3 and Appendix 16; Technical Resources Report, Section 2.4 for descriptions and conclusions concerning subsidence. These documents often refer to E.A. DOI-BLM-CO-SO10-2011-0074-EA which can be located in Appendix 18. Dunn Ranch LBA E.A. (King II Appendix 15, Section 3.3): "Cultural resources (Table 3-6) could be impacted by subsidence as they are located above proposed panels. However, potential subsidence is expected to occur very infrequently at King II due to a variety of factors, such as the stability of the Cliff House sandstone (Section 3.4.6). As noted in Section 3.4.6, the subsidence that has occurred has been less than 1 foot in depth, and 0.25 to 0.5 ft in width. In the existing federal permit and lease areas, no effects to historic properties have been observed due to subsidence. Based on known occurrences and frequency of subsidence in the existing mine area, no subsidence impacts to NRHP-eligible orpotentially eligible sites are anticipated." GCC Energy, LLC King II Mine Section 2.05.6 Page 18 June 12, 2020 (PR-10)