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831 - 032.793 <br />May 2012 <br />Fall 2011 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide 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 completed by MCC personnel. Copies of these <br />inspection forms can be found in Appendix A. MCC also collects substantial information from <br />the vicinity of Minnesota Reservoir and Monument Dam, such as visual inspections, survey data, <br />piezometer and inclinometer data, and annual aerial photo comparisons (Appendices B and C). <br />In addition, MCC monitors USFS water resources (Appendix D), Dry Fork Road survey data <br />(Appendix E); Dry Fork channel survey data which includes culverts, flumes, well and thalweg <br />survey data of all water conveyance structures over the Dry Fork Lease (Appendix E); and the <br />Lower Cow Camp Subsidence Survey Data (Appendix F). Also included is a map (Appendix G) <br />of 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 <br />with the actual data provided in Appendix B. An annual aerial photographic comparison of the <br />Minnesota Reservoir /Monument Dam area is conducted each fall to assess movement in the <br />landslides north and south of the reservoir. This discussion and these aerial images are found in <br />Section 4.2 and Appendix C. Section 4.3 discusses the 2011 Water Resources Project Survey <br />Report for the USFS as required in the permit and included as Appendix D. Additional details <br />regarding the monitoring of Dry Fork Road subsidence, Dry Fork channel survey data across the <br />Dry Fork Lease, and the Dry Fork Thalweg can be found in Section 4.4, while monitoring of the <br />Lower Cow Camp is discussed in Section 4.5. <br />Data and discussions associated with this section (excluding Section 4.2 and Appendix C) are the <br />responsibility of MCC and is provided in this WWE report for convenience. <br />Wright Water Engineers, Inc. Page 25 <br />