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Fall 2014 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas <br />4.0 OTHER SUBSIDENCE - RELATED DATA <br />In addition to the semi - annual traverses conducted by WWE above longwall mining areas, MCC <br />has been collecting data from numerous other monitoring locations. For example, regular <br />inspections of USFS roads and stock ponds are performed by MCC personnel. Copies of these <br />inspection forms can be found in Appendix A. MCC also collected substantial information from <br />the vicinity of Minnesota Reservoir and Monument Dam, such as visual inspections, survey data, <br />and annual aerial photo comparisons (Appendices B and Q. In addition, MCC monitors USFS <br />water resources in the vicinity of mining (Appendix D). Also included is a map (Appendix E) of <br />the actual extent (as of the date of the map) of the mined E -seam longwall panels within the <br />Maximum Projected Areal Extent of Potential Mineable E -seam as shown on approved Permit <br />Map 51. Within these appendices, note that the term "recent displacement" indicates that the <br />displacement shown is the difference in the measurements recorded in the last two surveys. <br />A general discussion of the Minnesota Reservoir and Monument Dam follows in Section 4.1 with <br />the data provided in Appendix B. An annual aerial photographic comparison of the Minnesota <br />Reservoir /Monument Dam area is conducted each fall to assess movement in the landslides north <br />and south of the reservoir. This discussion and these aerial images are found in Section 4.2 and <br />Appendix C. Section 4.3 discusses the 2014 Water Resources Project Survey Report for the USFS <br />as required in the permit and included as Appendix D. <br />Data and discussions associated with Sections 4.1 and 4.3 are the responsibility of MCC and are <br />provided in this WWE report for convenience. <br />4.1 Monument Dam /Minnesota Reservoir Monitoring Data <br />Beginning in 2006, numerous monitoring stations were established on Monument Dam and at <br />strategic locations around Minnesota Reservoir as a means to collect baseline information about <br />water levels and potential surface /subsurface movement. Monitoring locations included three <br />historic standpipe piezometers, four boring locations each with three nested piezometers, two <br />inclinometer locations (one on the dam and one in the landslide area south of the dam), and <br />numerous survey mirrors for evaluation of surface movement on and near the dam. Many of these <br />locations have been monitored monthly from July 2006, while others were added to the monitoring <br />831 - 032.796 Wright Water Engineers, Inc. Page 22 <br />March 2015 <br />