2018-07-02_PERMIT FILE - C2010089 (16)

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Plans for sampling overburden and topsoil to identify potentially deleterious materials have been developed and are outlined in Section 2.05.4(2)(d) Overburden and Topsoil Handling. As previously mentioned, investigations have determined that no acid or toxic materials will be replaced in the upper four feet of the regraded spoil (Section 2.04.6 Geology Description). Surface runoff from reclaimed areas will not come into contact with materials that would contribute to elevated levels of acid or toxic constituents in the runoff. Topsoil handling procedures (Section 2.05.4(2)(d) Overburden and Topsoil Handling) and revegetation methods (Section 2.05.4(2)(e) Revegetation) have been developed to prevent erosion and minimize the additional contribution of sediment to runoff. Plans presented in both sections include the establishment of topsoil piles, temporary seeding of topsoil piles, disking, mulching, deep ripping and prompt reseeding of reclaimed areas. Culverts presented in the surface water control plans have been designed to include appropriate headwater and tailwater depths and outfall protection (riprap) to minimize erosion. Surface Water Ouantity The sediment ponds, collection ditches and culverts have been planned and located to control all drainage into, through and out of the NHN mining area and to ensure that changes in surface water quantity are minimized. The postmining topography is planned to approximate the pre -mining contours (see Section 2.05.4(2)(c) Backfilling and Grading). Replaced topsoil material will exhibit infiltration rates similar to pre -mining soils. Reclamation techniques used in the top soiled areas (disking, ripping, mulching, etc.) in combination with reestablished watershed topography will minimize excessive rates and volumes of runoff. Stream Buffer Zones As indicated in Section 4.05.18 Stream Buffer Zones, buffer zone protection is required for Meehan Draw as defined by Rule 4.05.18. Map 4.05.18-1 shows that no collection ditches which route runoff from disturbed areas to the sediment ponds will be constructed within the buffer zone for Meehan Draw. The operations plan for collection ditch construction calls for no disturbance to the main channel of the draw, no excavation within the 100 foot buffer zone and that the collection ditches are capable of conveying the runoff from a 10 -year, 24-hour storm to the retention ponds. The ditch will be reclaimed and the ground surface reshaped to its approximate original contour. The plan calls for reseeding with a seed mix consistent with the approved postmining land use. WATER RIGHTS The surface water rights, namely, the shareholders of Colorado Cooperative Company 2nd Park Lateral are listed in Appendix 2.04.7-2 and the ground water rights (water wells) adjacent to the Section 2.05.6(3)(b)(v) Page 3 March 2018 (TR -16)