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Fall 2013 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mininq Areas <br />As of the time of the 2013 aerial photograph (May), mining of E -seam Panel E1, E2 and E3 were <br />complete and E -seam Panel E4 was approximately 30 percent complete with mining progressing <br />from southeast to northwest. <br />4.3 U.S. Forest Service Water Resources Survey <br />MCC is required, as part of their permit, to monitor USFS water resources (i.e., reservoirs and <br />stock ponds). Appendix D of this report is the 2013 Water Resources Project Survey Report <br />generated for this purpose. <br />4.4 Subsidence Monitoring of the Dry Fork Road, Channel, and Water Monitoring <br />and Conveyance Structures <br />Beginning in November 2010, numerous monitoring stations were established along the Dry Fork <br />Road on the ground surface above Longwall Panels E2 and E3. These stations provided a means <br />to collect baseline information before longwall mining and to document the amount of vertical <br />displacement, tilt, and horizontal strain on Dry Fork Road after longwall mining has been <br />completed. Similarly, MCC collected required baseline information on water monitoring, <br />conveyance structures (i.e. flumes, culverts, and wells), as well as the thalweg while within the <br />projected angle of draw of longwall panel subsidence. <br />Surveys of the deepest part of the Dry Fork stream bed (thalweg), from where the flume crosses <br />Deep Creek to Minnesota Reservoir, were performed and data from all three surveys have been <br />presented in previous reports. These surveys included the invert and outlet elevations on all flumes <br />and corrugated metal pipe culverts along this reach. Previous reports included a comparison of <br />the Northing, Easting, and elevation for each data point within the survey. These comparison <br />revealed changes (some larger than others) that have occurred between surveys. Some of the <br />differences can be accounted for by increased beaver activities, which prevented access to some <br />survey locations, while other differences appeared to be the result of continued erosion of the <br />stream channel by natural means. It should also be noted that individual survey markers were not <br />set at each survey station. As a consequence, the second and third surveys attempted to relocate <br />the original survey location using global positional system (GPS) coordinates. In most instances, <br />the second and third survey locations were a reasonable representation of the original. However, <br />831 - 032.795 Wright Water Engineers, Inc. Page 27 <br />January 2014 <br />