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Postmine Slopes <br />Transect Rise, ft Run, ft Slope, % <br />A 5 110 4.5% <br />B 5 80 6.3% <br />C 10 190 5.3% <br />D 30 1130 2.7% <br />E 30 710 4.2% <br />Average Slope / transect 4.6% <br />With the basic slope analysis illustrated above and a visual comparison; the entire property is <br />shown planned to be graded to a flatter, uniform slope that lends itself to multiple farming and <br />irrigation techniques, including methods that were used prior to mining disturbance. The <br />approved postmining land use for the Morgan property was irrigated cropland. The approved <br />postmining topography plan supports that same land use, and creation of the postmining <br />landscape as approved in the permit would not be expected to represent a degradation in the <br />capability of the landowners to use the same types of irrigation methods as were utilized prior to <br />mining disturbance. OSM also finds that the shallow slopes planned are within reason and <br />capable of a static safety factor of 1.3 or greater. <br />In addition to reviewing the approximate original contour (AOC) plans on the Morgan property, <br />OSM received a citizens compliant letter concerning the reclaimed postmining surface on the <br />Benson property which is north of the BB road and near to the Morgan property. Specifically, the <br />concern expressed was that the Benson property had been backfilled and graded 25 -feet higher <br />which may cause spoil seepage draining onto the Morgan property. The written concern did not <br />specify what the re- graded Benson property was higher than, but OSM has assumed that the <br />author of the compliant meant that the postmining Benson property was now 25 feet higher than <br />the premining topography, since the complainant stated that they have lost their view. <br />After reviewing permit Map 2.05.4 -1 `Existing & Projected Reclamation Contours New Horizon <br />#2 Mine' and Map 2.04.7 -1A `Hydrologic Monitoring Site Location Map with Domestic Wells' <br />the following was found: <br />• The premining topography of the Morgan property had a high point of 5764 feet, which <br />largely drained to the west. Runoff was also collected and conveyed along the BB road <br />to the west where it tied into existing natural drainages. The premining surface had <br />multiple small drainage features that drained from the high point to the west and south <br />west where they were intercepted by natural drainages and the BB road. <br />• The currently approved postmining topography in the permit has a high point of 5745 - <br />feet within the Benson property. The majority of postmining topography also drains to <br />the west and south west, where it is intercepted by natural drainages and the BB road. <br />Permit cross - sections B -B' and D -D' on Map 2.05.4 -1, shows a premining versus <br />postmining surface comparison. This comparison illustrates that the premining surface to <br />the north of the BB road has been relatively evened out with the approved postmining <br />contour. There does appear to be some surface undulation, but this undulation appears <br />Page5of7 <br />