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Fall 2014 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas <br />3.9 Traverse G -G' <br />Traverse G -G' (previously known as Traverse L -L') is located along the Horse Gulch Road from <br />its connection with Dry Fork Road (east of Minnesota Reservoir) northward to the fork that either <br />leads to Apache Rocks (westward) or Sylvester Gulch/West Flatiron (eastward). No subsidence <br />features were noted along this traverse at the time of our fall 2014 field visit. <br />3.10 Photographic Observation Point 4 <br />This location was established on September 27, 2007, at the MCC monitoring station that <br />overlooks Monument Dam and Minnesota Reservoir from the north (see Map 1). From this <br />location, various features associated with a large landslide south of the Minnesota Reservoir can <br />be readily identified including the head scarp, hummocky topography, and numerous spring and <br />wetland areas (i.e., discharge locations from the landslide mass). Images from this location have <br />been obtained each field visit since 2009. Images obtained from the fall 2014 field visit show very <br />little discernable difference from those obtained over the last several years and are therefore <br />excluded from this report. A comparison of spring 2009 and spring 2013 images can be found on <br />page 24 of the Spring 2013 Subsidence Report. <br />3.11 Traverse H -H' <br />Traverse H -H' (formerly Traverse N -N') begins where the Deer Creek drainage meets the Dry Fork <br />Road and continues southward up- valley to a locked gate near two open plastic stock water tanks <br />(see Map 1). <br />This traverse is located above the projected E -South Mains and the western ends of mined E -seam <br />Longwall Panel E4 as well as unmined E -seam Longwall Panels E5 and E6. The lower (north) <br />end of the drainage is located above mined E -seam Longwall Panel E3, which was undermined in <br />December 2012. The E -seam overburden depth is approximately 400 feet at the north end of the <br />traverse and increases to about 500 feet at the south end. The estimated alluvial thickness ranges <br />from 30 to 50 feet in this area. The fall 2014 observations found no subsidence - related features <br />along this traverse. Note that this traverse crosses the tension zone above the southwest edge of <br />mined E -seam Longwall Panel E4. The estimated E -seam overburden thickness at this location is <br />approximately 450 feet. <br />831 - 032.796 Wright Water Engineers, Inc. Page 14 <br />March 2015 <br />