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Subsidence and Geologic Field Observations <br />Apache Rocks and Box Canyon Mining Areas <br />July 12-15, 2004 <br />4.3.3 Traverse O-O' <br />This foot traverse begins at the fork in the road to Horse Gulch and the drill road to methane <br />drainage well site MDW-16-08 and ends at MDW-]6-08. <br />• Traversed in road cut down Sylvester Gulch then southwazd to the well site above mined <br />longwall panel 16. <br />• The road cut is primazily in the alluvium of Sylvester Gulch, which is estimated to be 50 to <br />75 feet thick, then in colluvium and weathered bedrock (Barren Member of the Mesaverde <br />Formation) up the south side of Sylvester Gulch to the welt site. <br />• Overburden depth to the B Seam ranges from about 950 to 1,050 feet. <br />• No subsidence features were observed. A few irregular desiccation cracks (up to 1.4 inch <br />wide) were observed in the road neaz the well site. <br />• No subsidence features have been observed in the alluvial valleys of Deep Creek and <br />Sylvester Gulch above mined longwall panels (even where the overburden is about 950 feet <br />thick). <br />Location 13: <br />Subsidence cracks at Apache Rocks (compaze with Location 13 in the 2002 and the 2003 <br />reports). <br />No subsidence features were observed along the road from the Horse Gulch gate to Apache <br />Rocks, which is located above mined longwall panels 13 and 13A (although this stretch of road <br />was not identified as a traverse). <br />• Cracks in the sandstone of the Barren Member of the Mesaverde Formation appeaz to be the <br />same width as last year (Figures 16 and 17). The crack surfaces, however, appeaz slightly <br />831-032.640 Wright Water Engineers, Inc. Page 32 <br />September 2004 <br />