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overburden is about 1,000 feet thick at this location. These springs may be minimally impacted. <br />Spring 35-1 is located above the center of panel E3 along Deep Creek. The overburden is about <br />1,000 feet think at this location. This spring may also be minimally impacted. Springs 36-1 and 35-2 <br />are located along a tributary of Deep Creek and have overburden depths of 950 and 1,000 feet. <br />They are located outside of the influence of longwall mining and should not be affected. <br />11.4.2 Water-Bearing Zones <br />Horizontal strain produced during subsidence could impact local water-bearing zones in bedrock <br />beneath the blanket of clay-rich surficial material. It also may impact local water-bearing zones in <br />surficial material, where permeable and saturated zones are stratigraphically positioned in zones of <br />tensile strain. Impacts may occur for long periods of time, where the water-bearing zone is located <br />above mine boundaries and barrier pillars, areas where permanent strain occurs. On the other <br />hand, dynamic strains and related cracks produced by subsidence above moving longwall faces in <br />a given area are nil and close when the longwall faces move out of the area of influence of this <br />area. Based on Dunrud's evaluation, any mining effects on local on waterbearing zones can best be <br />identified by monitoring any changes in flow and water levels in springs and ground water wells (as <br />discussed in Section 11.4.3). <br />11.4.3 Ground Water Wells <br />The two monitored, ground water wells (23-H-1 and 23-H-2) in the South of Divide mining area are <br />located east of, and near the mouth of Deer Creek. They are located above, or within the areas of <br />mining influence of, the barrier pillar areas and haulageways of projected longwall panels E2 and <br />E3. Overburden depth to the E Seam is approximately 375 to 400 feet. The major source of the <br />water in these is wells likely from colluvium and alluvium in the Deer Creek drainage. There are <br />also two groundwater monitoring wells in the Dry Fork mining area. A shallow well in the upper Dry <br />Fork was reportedly installed in 2003 but-is no longer monitored and its status is unknown. (U.S. <br />Dept. of Agriculture, 2005) A groundwater monitoring well (96-2-2) was completed to bedrock by <br />the West Elk Mine is monitored three times a year. This groundwater monitoring well is located <br />approximately 500 feet east of the bleeder entires of panel E3 and approximately 500 feet north of <br />the bleeder entries of panel E4. It is outside of the angle of draw for the longwall mining and should <br />not be affected. <br />These wells, and any other water wells within the area of mining influence should continue to be <br />monitored (or begin to be monitored) for as many years prior to mining as possible, in order to <br />determine baseline information that would yield seasonal variations. <br />11.5 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. Large, extensive cracks were observed on Jumbo Mountain in landslide areas; <br />however, they were considered to be exclusively caused by the natural landslide process. <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 and Dry Fork mining areas. Also, no effects from landslide movements or rockfalls are <br />expected, because the highest rockfall potential is mapped in the high category. Rockfalls were <br />observed to occur only in the very high rockfall category areas in the Box Canyon mining area. <br />Although no cracks are expected in the soft, pliable alluvium, some cracks are expected to occur on <br />the harder and more highly compacted Dry Fork access road, particularly in the area near the <br />confluence of Deer Creek and Dry Fork. As discussed previously, the range of maximum vertical <br />displacement, tilt, and horizontal strain is projected to be 8.4 to 11.2 feet, 1.3 to 6.4 percent, and 0.7 <br />to 4.2 percent (respectively) in the North Fork stream valley and road above the solid coal <br />boundaries at western limits of longwall panels E2 and E3. <br />Tetra Tech - 0907171P 28