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Fall 2016 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas <br />3.0 OTHER SUBSIDENCE MONITORING <br />MCC has been collecting data from numerous monitoring locations in and around Minnesota <br />Reservoir, Monument Dam and the general Dry Fork area for many years. Ongoing monitoring <br />by MCC personnel includes the Monument Dam and Minnesota Reservoir area, as well as U.S. <br />Forest Service (USFS) roads and stock ponds. Survey data and inspection forms for these areas <br />are provided in Appendix A and B, respectively. Please note that the term "recent displacement', <br />as used in Appendix A, indicates that the displacement shown is the difference in the measurements <br />recorded in the last two surveys. 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 3.2 and <br />Appendix C. In addition, MCC monitors USFS water resources in the vicinity of mining and <br />generates a permit -required annual report that is included as Appendix D. Also included with <br />this report is a map (Appendix E) that represents the actual extent (as of the date of the map) <br />of the mined E -seam longwall panels within the Maximum Projected Areal Extent of Potential <br />Mineable E -seam as shown on approved Permit Map 51. Data and discussions associated with <br />ongoing MCC monitoring are provided by MCC and included in this W WE report for convenience. <br />3.1 Monument Dam/Minnesota Reservoir Monitoring <br />As described in previous subsidence reports, MCC has conducted monitoring of the Monument <br />Dam and strategic locations around Minnesota Reservoir since 2006. Currently, MCC has <br />monitoring and reporting responsibilities for the land survey stations. Data collected from various <br />monitoring locations on the Monument Dam (including Dam Inspection Forms) are provided in <br />Appendix A. <br />Quarterly land surveys of the monuments (monthly when mining is within one mile of the dam) <br />were completed. A summary of both average height and longitudinal displacement data obtained <br />from spring 2016 to fall 2016 is provided in Table 1 of Appendix A. <br />831-032.798 Wright Water Engineers, Inc. Page 7 <br />January 2017 <br />