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Section 2.05.3(3) have been designed to ensure that the hydrologic balance is protected. The <br />discussion for surface water protection has been separated into three parts: 1) surface water <br />quality; 2) surface water quantity; and 3) surface water monitoring. <br />Surface Water Quality Sediment ponds will be adequately designed and will be constructed <br />during operations for controlling surface water runoff from disturbed and reclaimed areas. An <br />NPDES permit will be obtained from Water Quality Control Division, Colorado Department of <br />Public Health and Environment to allow the discharge of water from the sediment ponds. The <br />design of the ponds has been developed to prevent additional contributions of sediment to stream <br />flow outside the permit area, to minimize erosion, and incorporates detention times sufficient to <br />ensure that all applicable effluent standards will be met. The pond discharge structures are <br />designed according to standard engineering design procedures for protecting against erosion via <br />emplacement of riprap and/or energy dissipaters. The pond will be removed and reclaimed when <br />the entire watershed reporting to the pond has been approved for Phase II bond release. The <br />impact of a sediment pond and runoff from reclaimed areas on the quality of receiving streams <br />was found to be of minimal significance (see Probable Hydrologic Consequences at the end of <br />this section). <br />Plans for sampling overburden after backfilling and grading have been developed and are <br />presented in Section 2.05.4(2)(d), Topsoil Redistribution. Based on these plans, surface runoff <br />from disturbed reclaimed areas will not come in contact with materials that would contribute to <br />elevated levels of acid or toxic constituents. <br />Topsoil handling procedures (Section 2.05.4(2)(d), Topsoil Redistribution) and revegetation <br />methods (Section 2.05.4(2)(e), Revegetation) have been developed to stabilize the landscape, <br />prevent erosion, and minimize the additional contributions of sediment to runoff. They include: <br />the seeding of temporary disturbance and topsoil piles; mulching, chisel plowing and deep <br />ripping; cover cropping; and timely reseeding of reclaimed areas (regraded and topsoiled) with <br />seed mixes designed for rapid establishment and development of effective hydrologic cover. <br />Those areas that are affected by mining will be graded to post mining topographies that generally <br />feature slopes no greater than 5:1. In combination with the reclamation and topsoil handling <br />techniques, reduced slopes will minimize the potential for erosion due to accelerated sheet wash <br />or gullying. <br />Diversions will be designed according to accepted design criteria, and will be built to minimize <br />erosion and prevent additional contributions of sediment by limiting the flow velocities and <br />tractive forces that cause erosion. Temporary diversions in place longer than a growing season <br />will be seeded with a temporary seed mix as outlined in Section 2.05.4(2)(e). Diversions have <br />been designed to maximize geomorphic stability while minimizing disturbance. All temporary <br />diversions will be removed and reclaimed after mining activities have been completed. Plans <br />Section 2.05.6(3) Page 5 April 2016 (PR -01) <br />