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Item <br />Vertical <br />subsidence <br />magnitude <br />Horizontal <br />displacement <br />magnitude <br />Angle of draw <br />USFS roads <br />USFS ponds <br />Predicted impact in Observed impact Prediction accurate? <br />permit application <br />Maximum 18.4 ft. <br />in two-seam <br />mining areas. Between 2000 and 2007 visual Although subsidence <br />Less than 1 ft. observations are used for displacements have not been <br />near panel edges verifying the conceptual surveyed since 1999, visual <br />in single-seam subsidence model, rather than observations described in the <br />mining areas. quantitative monitoring. The Fall Fall 2007 report indicate <br /> 2007 report included data from a subsidence displacements and <br />Maximum pre-mining surveys over panel E- the angle of draw have <br />horizontal strain 1 and the thalweg of the Dry Fork probably not significantly <br />of 3.9% of Minnesota Creek. exceeded the predicted values. <br />8 - 21 degrees <br />Rockfalls, No rockfalls or cracking found in Yes <br />cracking visual survey for Fall 2007 report <br /> No draining by subsidence cracks <br />Draining found in visual survey for Fall Yes <br /> 2007 report.