2018-10-24_PERMIT FILE - C1982056A (2)

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Since the intent of Rule 4.14.6 is to allow stabilization through means other than regrading, every alternative means will be employed prior to using machinery to alleviate an erosion problem. If such action becomes necessary, one of the small rubber-tired farm tractors utilized in reclamation will be allowed on the site to re-grade the gully. Once a site is regraded, it will immediately be planted to the appropriate perennial seed mixture. Details concerning the backfilling and soil stabilization of the Fish Creek Tipple operation are found within Volume VII, Fish Creek Tipple/LoadOUt Appendix, on pages 2.05-33 through 2.05-37. (d) A plan for removal from storage and redistribution of topsoil subsoil, and other material to meet the requirements of 4.06. RESPONSE The location and volume of all stockpiled topsoil materials are shown on Map 29, Reclamation. Topsoil stockpiles are located on stable surface areas where the likelihood of disturbance or contamination by the mining operations is minimal. Stabilization of the storage piles has been achieved with one of the perennial seed mixtures. In the event that the side slopes of the revegetated topsoil stockpiles do not become adequately vegetated, then alternate methods may be used for stabilizing the side slopes. The slopes may be reduced to facilitate revegetation or an erosion netting or a geotextile may be placed over areas that are not adequately revegetated. In reference to the erosion netting a product such as Curlex Excelsior Blankets, Polyjute or similar type products can be utilized to minimize wind and water erosion of the stockpile. The other option would be to use an erosion control geotextile such as one produced by Mirafi, or similar type produced by other manufactures. If these products were used they would be installed per the manufactures recommendation, which typically involves unrolling the product and stapling it to the ground. Likewise,the sections, where required, would be overlapped and stapled to the ground. Redistribution of the soil will be done, wherever practicable, at a time when the physical, chemical, and biological properties of the soil can be protected from alteration while minimizing the potential for erosion. If feasible, redistribution will take place during the early summer and fall when the soil moisture levels help reduce the emission of particulate dust. Regrading topsoil during these seasons with a dozer or rubber tired blade will also minimize compaction. Frost action plus wetting and drying should loosen most compacted zones to a depth of 20 inches, even in soils with a high clay content, as documented by Shafer et al., (1979). Leaving graded spoils in a roughened condition will alleviate slippage surfaces. Problems with a root penetration are mitigated by application of topsoil to rough-graded spoil. Numerous field and greenhouse studies conducted by Dr. W.J. McGinnies of the USDA-SEA-ARS on mine spoil from the Energy Mine No. l have documented that physical differences between reapplied topsoil and the underlying materials do not affect root penetration. In general, all available suitable soil materials will be recovered from planned disturbance areas prior to other disturbance, with either direct replacement on active reclamation areas or placement in temporary stockpiles so that the soil materials are available for future reclamation of mine disturbance areas. Following backfilling, grading, and establishment of appropriate drainage control features, soil materials will either be directly replaced, or recovered from stockpile and replaced on reclaim areas. Reasonable efforts will be made to replace and grade soil materials to a uniform depth, and the replaced soils will be left with a roughened surface to minimize erosion and facilitate water capture and infiltration. The reconstructed soil profile depth will be similar to the premine thickness and will be fully capable of supporting plant growth needed for the proposed postmining land use. The beneficial effects of as little as 2 inches of topsoil were demonstrated by Schuman and Power, 1980 in a paper entitled, "Plant Growth as Affected by Topsoil Depth and Quality of Mine Lands". After redistribution and as soon as conditions allow,the topsoil will be graded to assure a uniform and stable thickness onsistent with the proposed postmining land use, contours, surface water drainage system, and revegetation requirements. Application and subsequent blading along the contour will reduce erosion potential of all topsoiled areas. Wind and water erosion control will be accomplished as described under Rule 2.05.4(2)( c) above. RN 17-07 2.05-108 02/15/18