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West Elk Mine <br /> <br />2.05-114 Rev. 06/05- PR10, 03/06- PR10, 05/06- PR10, 11/060- TR107, 04/07- TR108, 09/07- PR12, 02/08- PR12; 11/10- MR372; 10/20- MR-452; <br /> 12/20- TR149; 12/21- TR150, 1/24-TR152 <br />and barrier pillars - areas where permanent strain occurs. On the other hand, dynamic strains and <br />related cracks produced by subsidence above moving longwall faces in a given area are nil and <br />close when the longwall faces move out of the area of influence of this area. Based on this <br />evaluation, any mining effects on local aquifers can best be identified by monitoring any changes <br />in flow and water levels in springs and ground water. <br />Ground Water Wells <br />Ground water monitoring wells in the South of Divide mining area were located east and near the <br />mouth of Deer Creek and were above, or within the areas of mining influence of the barrier pillar <br />areas and haulageways of mined longwall panels E2 and E3. Overburden depth to the E seam is <br />approximately 375 to 400 feet at that location. The major source of the water in these wells was <br />likely from colluvium and alluvium in the Deer Creek drainage. These E seam panels were <br />mined in 2011 and 2012 and monitoring data reported in the Annual Hydrology Reports for <br />those years. <br />Monitoring wells, flumes, and road culverts located within the anticipated angle-of-draw of panel <br />subsidence will be surveyed for locations and elevations at least one month or more prior to <br />subsidence. These features will then be surveyed on a quarterly basis. Monitoring will cease <br />after no significant movement is noted during two consecutive quarterly surveys. The results of <br />the surveys will be submitted with the semi-annual subsidence reports. <br />Roads <br />No significant effects from mining subsidence are expected on most of the access roads and drill <br />roads in the mining areas. Also, no effects from landslide movements or rockfalls are expected, <br />because the highest rockfall potential is mapped in the high category. Rockfalls were observed <br />to occur only in the very high rockfall category areas in the Box Canyon mining area. Although <br />no cracks are expected in the soft, pliable alluvium, some cracks are expected to occur on the <br />harder and more highly compacted Dry Fork access road, particularly in the area near the <br />confluence of Deer Creek and Dry Fork. <br />Roads will be monitored six months before they are within the angle of draw and on a weekly <br />basis while they are within the angle of draw. After the roads are outside the angle of draw, <br />monitoring will continue on a monthly basis for six months. All road monitoring is dependant <br />upon accessibility. Results of the monitoring will be submitted with the semi-annual subsidence <br />reports. The report will include a description of observations, date of observations, and needed <br />repairs, if any. <br /> Buildings <br />Baseline information on buildings, such as foundations, walls, chimneys, and roofs, were obtained <br />prior to any mining on the Dry Fork Cow Camp in July 2004. A pre-mining survey of the Cow <br />Camp structures was performed Wright Water Engineers and was reported in Exhibit 60D, and <br />another survey was conducted by West Elk Land Surveying in February 2006 and is included in <br />Exhibit 73. No buildings will be impacted in the Dry Fork Lease area (Ditch Rider’s Cabin). <br />Impacts Beneath the Mined Coal Seam