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Subsidence Field Observations <br />West Elk Mine <br />August 28 and 29, 2001 <br />3.2.8 Traverse G-G' <br />Traverse G-G' is located near the upper East Fork and part of the West Fork of Horse Gulch <br />above mined-out longwall panel 12 and the northern part of longwall panel 13. <br />• The overburden thickness along the traverse ranges from 1,250 to 950 feet. <br />• No subsidence features were observed in the soil and colluvium along the traverse. <br />3.2.9 Traverse H-H' <br />Traverse H-H' is from the fork in the drill road on a ridge to the water monitoring wells SOM 23- <br />H-1 and SOM-23-H-2 above mined-out longwall panels 12 and 13. <br />• The overburden thickness ranges from about 1,300 down to 600 feet. <br />• No subsidence features were observed in the soil and colluvium along the traverse. <br />• One small desiccation crack was observed in the dam of a small pond at Location 15A <br />of 2000, which is located above the southern edge ofmined-out longwall panel 13A. <br />3.2.10 Traverse I-I' <br />Traverse 1-1' extends across Minnesota Reservoir dam, then up the lower Horse Gulch Trail. <br />• The water level in the reservoir appears to be 50 to 70 feet below the high water mark, <br />and perhaps 25 to 30 feet below this year's high water level. The water from Minnesota <br />Reservoir is flowing out through the dam outlet pipe. <br />• The overburden depth to the B-Seam, in the area effected by the major landslides, ranges <br />from approximately 400 to 700 feet. <br />• The hummocky topography and recent landslide scarps occur on the north and south sides <br />of the reservoir (Figures 7 and 8). <br />831-032.560 Wright Water Engineers, Inc. Page 12 <br />September 2001 <br />