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West Elk Mine <br />• author's evaluation, any mining effects on local on aquifers can best be identified by monitoring <br />any changes in flow and water levels in springs and ground water. <br />Ground Water Wells <br />Two monitored, ground water wells (23-H-1 and 23-H-2) of 10 wells monitored in the South of <br />Divide mining azea aze located east, and neaz the mouth of Deer Creek. They are located above, <br />or within the azeas of mining influence of, the barrier pillaz azeas and haulageways of projected <br />longwall panels E2 and E3. Overburden depth to the E seam is approximately 375 to 400 feet. <br />The major source of the water in these is wells likely from colluvium and alluvium in the Deer <br />Creek drainage. <br />These wells, and any other water wells within the area of mining influence will continue to be <br />monitored i.e. SOM 3B and SOM 3E(or begin to be monitored) for as many years prior to <br />mining as possible, in order to determine baseline information that would yield seasonal <br />variations. <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 report. <br />Roads <br />With the exception of the presence of minor subsidence cracks on an access road to Jumbo <br />Mountain, no subsidence features (cracks or bulges) were observed during the annual subsidence <br />observations. Lazge, extensive cracks were observed on Jumbo Mountain in landslide azeas; <br />however, they were considered to be indistinguishable from mining the B Seam. <br />Based on past observations in the Apache Rocks and Box Canyon mining areas, no significant <br />effects from mine subsidence are expected on most of the access roads and drill road in the South <br />of Divide azea. Also, no effects from landslide movements or rockfalls are expected, because the <br />highest rockfall potential is mapped in the high category. Rockfalls were observed to occur only <br />in the very high rockfall category areas in the Box Canyon mining azea. <br />Although no cracks are expected in the soft, pliable alluvium, some cracks aze expected to occur <br />on the hazder and more highly compacted Dry Fork access road, particulazly in the azea near the <br />confluence of Deer Creek and Dry Fork. As discussed previously, the range of maximum <br />vertical displacement, tilt, and horizontal strain is projected to be 8.4 to 11.2 feet, 1.3 to 6.4 <br />percent, and 0.7 to 4.2 percent (respectively) in the North Fork stream valley and road above the <br />solid coal boundaries at western limits of longwall panels E2 and E3. <br />Roads will be monitored six months before they aze within the angle of draw and on a weekly <br />basis while they aze 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 />2.05-1 SS Revised June 1005 PRIO, Rev. Minch 1006; May 2006 PR10 <br />