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possible limited overburden, it may not be possible to achieve complete side slope reclamation <br /> by backfilling with available overburden material. The result is, depending upon the amount of <br /> overburden material recovered and available for reclamation, side slope backfilling may need to <br /> be enhanced with additional material from the pit floor. Using material from the pit floor will <br /> make the pit slightly deeper, but all slopes will still be maintained at 3H:1 V or shallower. <br /> Additional material required, if any, will be determined during mining as overburden material <br /> quantities and pit depths are verified. <br /> Materials Handling - Grading <br /> The 3H:1 V pit side slopes will be graded to transition into the relatively flat pit floor. Grading of <br /> the pit floor may leave a subtle rolling topography rather than a completely flat bottom <br /> depending on varying depths of the sand and gravel deposit. The side slopes will also not be <br /> graded smooth, but will contain a low profile ridging pattern that follows the contour. Final <br /> grading that leaves this type of ridging pattern helps to capture water for plant growth as well as <br /> reduce the velocity of runoff and slope erosion. On these slopes, erosion may present a <br /> maintenance issue for the first year or two of revegetation if there are large, drenching <br /> thunderstorms, but more normal low intensity thunderstorms should not create more than minor <br /> rilling. <br /> All backfilling and grading will be done to stabilize the material and control erosion. Final <br /> grading and seeding will be done as soon as possible after backfilling, grading, and topsoiling <br /> have been completed. There will not be known toxic or hazardous materials in the backfill <br /> material. The reclamation will not leave high walls on the property. In addition, there will be no <br /> auger holes,excavations, or shafts left on the property. <br /> Topsoil and Reve etg ation <br /> The growth medium for revegetation will be a combination of overburden and topsoils. <br /> Unfortunately, there is not a large quantity of quality topsoil available at the site. Because of its <br /> thin occurrence, true topsoil stripping will likely incorporate some of the underlying silty clay <br /> overburden material. Every effort will be made to separate true topsoil stripping, but even with <br /> the incorporation of some overburden material, it is not anticipated that large quantities of the <br /> topsoil/overburden growth medium will be available for reclamation. <br /> Because of its limited availability, the topsoil/overburden growth medium may not be placed <br /> evenly over the entire site. The floor of the pit will likely need less growth medium because <br /> moisture accumulation there will help vegetation growth and new soil development. Therefore, <br /> only about 2 inches of the topsoil/overburden growth medium will be placed on the pit floor. <br /> The same dressing will be used for areas where stockpiles, access roads, or mining structures <br /> have been removed and the underlying material has been scarified in preparation for reclamation. <br /> A minimum of 4 inches of growth medium will be placed on backfilled pit slopes. The extra <br /> thickness of growth medium will help to retain moisture on the slopes and provide a deeper <br /> rooting zone to help protect against erosion. For slopes created by backfilling, growth medium <br /> will go on top of a considerable depth of overburden. When spreading growth medium on <br /> slopes, the same requirements for general grading will be followed. Final grading prior to <br /> Harmony Gardens Site <br /> DBMS Limited Impact 110 Permit Application Page 12 <br />