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Spring 2013 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas (E -Seam) <br />4.0 TRAVERSES AND OBSERVATIONS IN THE SOD AND DRY FORK MINING <br />AREAS <br />A detailed discussion of observations associated with Traverses A -A' through I -I' (along with <br />accompanying Maps 1 and 2) is provided in this section. Many of the photographs obtained during <br />the spring 2013 field visit are included as figures in the text of this report. Where these images <br />have notable differences from previous photographs, the older image has been included for <br />comparison purposes. To reduce the overall size of this document, narrative text and photographs <br />for traverses where no noticeable change was observed are generally not included in this report <br />and/or only generally discussed. Map 1 shows the outline of E -seam mining workings along with <br />surface topography and other surface features (including the named traverses). Map 2 shows the <br />same area and detail (except traverses) as Map 1 along with recently- active landslide and rockfall <br />areas as delineated from aerial photo research and field observations. <br />4.1 Traverse A -A' <br />This traverse originates approximately 2,000 feet southeast of the Two Ponds area (i.e., location <br />of U.S. Forest Service [USFS] Water Resource Ponds P69 and P70) at point A and continues <br />approximately 1.0 mile southward to its connection (point A') with the USFS Road 711 (Dry Fork <br />Road). This traverse crosses the eastern portion of mined E -seam Longwall Panels E1, E2 and <br />most of E3 (see Maps 1 and 2). <br />Weathered and fractured siltstone, claystone and sandstone bedrock are exposed in several <br />roadcuts along the steeper portions of this traverse. Flatter portions of the traverse are generally <br />stable and on mostly soil and colluvium derived from the Wasatch Formation and from intrusive <br />rocks of the West Elk Mountains that surficially blanket much of the SOD mining area. <br />Overburden depths along this traverse vary from 1,390 to 1,600 feet over the B -seam and 1,100 to <br />1,300 feet over the E -seam. <br />No subsidence - related features were observed along this traverse during our spring 2013 field visit. <br />831 - 032.795 Wright Water Engineers, Inc. Page 8 <br />September 2013 <br />