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Fall 2009 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mining Areas <br />• Light gray to brown soil, alluvium, and colluvium of the Barren Member of the Mesaverde <br />Formation are exposed along this road traverse. The soil, alluvium and colluvium are generally <br />stable due to the relatively gentle grade of the Sylvester Gulch valley bottom. <br />No subsidence features were observed and no photographs were taken. <br />5.3 Traverse C-C' <br />This traverse begins at the well site for E-seam Methane Well No. 1 (ESM-1) over mined B-seam <br />Longwall Panel 13, travels along the main access road to the Box Canyon mining area and West <br />Flatiron to the area known as Twin Ponds, and now heads southward to C' at a point where it <br />connects with Traverse I-I' over mined B-seam Longwall Panel 17. Traverse C-C' has remained <br />relatively constant for the last several observation periods. As of the fall 2009 field visit, the <br />upper end of the traverse and the location of C' has been changed (Map 1). The change in this <br />traverse is due to the reclamation of the road from Twin Ponds to D of Traverse D-D' and I of <br />• Traverse I-I' above the southern edge of mined Longwall Panel 14 (Map 1). <br />This traverse winds its way above mined Longwall Panels 13, 13A, 16 and 17. Light gray to <br />brown soil, colluvium, and local outcrops of siltstone and sandstone of the Barren Member of the <br />Mesaverde Formation occur in the road cuts. Overburden depth to the B-seam varies from 1,000 <br />to 1,450 feet. The colluvium and soil are locally unstable on road cuts along the traverse, which <br />causes slumping landslide deposits, primarily on the commonly-occurring steep slopes along the <br />middle portion of the traverse. <br />No subsidence features were observed. <br />5.4 Traverse D-D' <br />Traverse D-D' begins at point I of Traverse I-I' above the southern edge of mined Longwall Panel <br />14 and ends at the fork in the drill roads above the southern edge of mined Longwall Panel 24. <br />Soil, colluvium, and local bedrock of the Ohio Creek and Barren Members of the Mesaverde <br />Formation are exposed in the drill road. The soil and colluvium are locally unstable or quasi- <br />stable on the steepest slopes. <br />831-032.791 Wright Water Engineers, Inc. Page 24 <br />April 2010