2015-01-27_PERMIT FILE - C1996083A (2)

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2.05.6(6) The above multi -seam subsidence monuments have pre - longwall mining base line measurements, post D Seam longwall mining measurements and post B Seam longwall mining measurements. At the request of the USDA -FS, the Operator will monitor the topographic surface, soil and vegetation through interpretation of color aerial photographs. The portion of the Iron Point Lease managed by the USDA -FS was photographed on October 16, 2001 and again on October 13, 2006. The area will then be photographed in five year intervals. A set of the photographs will be supplied to the Forest Service and any changes to the topographic surface, soil or vegetation will be noted. Field investigation of changes may be required. Mitigation measures, if required, will be developed jointly between the Operator and the USDA -FS. The Operator will cease monitoring the topographic surface, soil and vegetation after the acquisition of a photographic record at least two years after the completion of mining. Immediately following retreat extraction in the immediate proximity of a stream, spring or pond, the intensity of monitoring that feature will be increased to once a month for six months. Flows in the West Fork of Terror Creek, collected at flume monitoring stations SW -1 and SW -12, will be available in real time, updated hourly. Real time data will not be available during high flow, freezing conditions or when real time data equipment is inoperable. In the absence of real time data, flow will be measured monthly, increasing to weekly when the West Fork of Terror Creek lies within the predicted angle of draw. Weekly flow measurements will be initiated three months prior and continue for six months following longwall extraction under the West Fork of Terror Creek. There will likely be periods of time during the winter months when the flumes are inaccessible. The Operator will visually inspect known historic and modern landslides within the permit and adjacent area for stability in June and November of each year. Additionally, known historic and modern landslides will be visually inspected once a month for six months immediately following retreat extraction in their immediate proximity. The Operator will evaluate each rejuvenated or new landslide to determine what the apparent cause of the modern movement might be. If appropriate, mitigation methods will be proposed to minimize hazard to the mine facilities, public health and safety, and the environment. PR -14 2.05-169- 09/12/14