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The operator has completed a survey of structures and renewable resource lands existing <br />within the permit area. Structures of concern include portions of Rio Blanco County <br />Road 65 and 97, a 138kV power line, the refuse haul road and stock ponds (Raven Park <br />Reservoir and Halandras Reservoir). Project impacts, monitoring plans and mitigation <br />measures are addressed within the application. <br />County Road 65 was visually monitored on a daily basis by the operator during periods <br />of undermining by D seam longwall operations, and repairs were made as necessary. <br />Road segments subject to subsidence were posted with appropriate warning signs. <br />Similar monitoring, repairs, and hazard signage will be conducted during B seam <br />extraction beneath the road. The two stock pond reservoirs referenced were impacted due <br />to longwall subsidence. The stock ponds were visually monitored during undermining <br />and damage was minimal and did not warrant repair. The power line is owned by BME <br />and the mine is the only customer served by the power line. Power structures within <br />areas of active subsidence will be monitored periodically by the operator and repaired if <br />necessary. <br />The operator has calculated the maximum predicted surface subsidence based on <br />previous mining conducted within the permit area, site specific geologic conditions, seam <br />thickness, and overburden depths, utilizing British National Coal Board (BCB) and US <br />Bureau of Mines modeling. The operator has predicted up to 7.7 feet of surface <br />subsidence for longwall mining areas and up to 0.5 feet of subsidence for room and pillar <br />mining areas. Based on predicted horizontal tensile strains, surface cracks up to several <br />inches wide are anticipated within zones of maximum subsidence, with the extent of <br />cracking dependent on the nature of near surface geologic strata and surface soil cover. <br />The operator has committed to a program of visual monitoring to identify subsidence <br />caused damage to surface structures, stock ponds, and major damages, and has committed <br />to repair hazardous tension cracks, subsidence features interrupting flow in Red Wash or <br />Scullion Gulch, or damage to surface structures. <br />Subsequent monitoring and observation have largely verified initial subsidence impact <br />projections. Current and future monitoring includes daily monitoring of County Road 65 <br />while mining below the road and during the active subsidence periods and twice - weekly <br />monitoring of Scullion Gulch and stock ponds during periods of undermining. <br />XVI. Concurrent Surface and Underground Mining <br />No specific approvals are granted to the applicant under this section. <br />XVIL Operations on Alluvial Valley Floors <br />The permit area and adjacent lands contain three stream channels — the White River, Red <br />Wash, and Scullion Gulch — with enough associated alluvium to be considered as <br />potential alluvial valley floors. All three channels cross the permit area as well as <br />M <br />