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FALL 2013 SUBSIDENCE AND GEOLOGIC FIELD OBSERVATIONS <br />South of Divide and Dry Fork Minina Areas <br />1.0 INTRODUCTION <br />Beginning in the spring of 2007, Wright Water Engineers, Inc. (WWE) has conducted semi - annual <br />(spring and fall) field visits to the area over the West Elk Mine as operated by Mountain Coal <br />Company, LLC (MCC) making subsidence and geologic observations. Prior to 2007, WWE <br />performed annual field visits dating back to 1996. Each of these visits provides observations <br />related to subsidence effects resulting from the longwall mining of coal in the B- and E- seams. <br />These observations have been subsequently chronicled in an annual or semi - annual subsidence <br />report 1. <br />This semi - annual subsidence report (Fall 2013 Report) is the second of two reports to be generated <br />based on observations made during the 2013 calendar year. In accordance with MCC's Colorado <br />Division of Reclamation, Mining and Safety (CDRMS) permit, subsidence reports are to be <br />submitted by April 30th (for preceding fall monitoring) and September 30th (for preceding spring <br />monitoring). Spring observations are regularly hampered by limited access due to snow or muddy <br />conditions and fall observations are typically scheduled around the various hunting seasons. <br />Historically, field observations have represented more than 80 percent of the text contained within <br />each of the semi - annual subsidence reports. The remaining 20 percent was repeated reference text <br />for the convenience of the reader. As of the Fall 2010 Report, WWE and MCC have made an <br />effort to reduce the size of the subsidence reports by removing repeated reference text. Each fall <br />report makes reference to the spring subsidence report for some of those details (e.g., traverse soil <br />types, thickness and sources, conclusions, and a bibliography). Also note that Appendix A of the <br />Spring 2013 Report provides a summary of the subsidence prediction information contained in <br />Annual and semi - annual subsidence and geologic field observation reports, as well as exhibits to the West Elk Mine <br />permit document (Exhibits 60, 60A, 6013, 60C, 60D, and 60E), are kept at Mountain Coal Company, LLC and at the <br />Colorado Division of Reclamation, Mining, and Safety. <br />831 - 032.795 Wright Water Engineers, Inc. Page 1 <br />January 2014 <br />