2016-01-07_PERMIT FILE - C2010089A (11)

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The post mining landscape is designed to protect the hydrologic balance by establishing slopes that generally will not exceed 5:1. Any highwall reductions will result in maximum slopes not to exceed 5:1. Reclaimed hillsides proposed for the New Horizon North mining area approximate the original pre -mining contours. Topsoil material will exhibit infiltration rates generally similar to pre -mining soils. At the NHN Mine, future reclaimed areas will be manipulated mechanically using chisel plowing and ripping of graded and top -soiled areas in combination with timely reseeding to minimize overland flow rates and volumes. Surface Water Monitoring WFC will continue to collect data from the baseline surface water monitoring sites (SW -N200 through SW -N209, minus SW -N206, destroyed by County maintenance) for the foreseeable future, (see Section 2.04.7 and Appendix 2.04.7-2). It is anticipated that some of the sites may be relocated (with DRMS consultation) as mining advances and that other sites may be added as circumstances require. As an example, the two sites monitoring the 2nd Park Lateral inflow and out flow, SW -N209 and SW -N200 respectively, will be affected when the irrigation water is diverted through the HDPE pipeline. Irrigation water will be reintroduced in the Garvey parcel during the reclamation phase of the NHN Mine. This will be a sprinkling type of system in contrast to the current "flood" system. Additionally, prior to mining, the NHN permit area will be managed to prevent irrigation water from entering the permit area. Surface water monitoring site SW -N205 will be affected in that the irrigation water will be shut off indefinitely. The surface water monitoring will be maintained for the life of the mining operation or until such a time as DRMS may agree that they are no longer necessary. Surface water monitoring installations, if any, will be removed upon completion of the post mining phase of the Hydrologic Monitoring Program. All surface water data collected at each monitoring site in each future water year will be compiled and submitted to DRMS in the form of the New Horizon Annual Hydrology Report (AHR) within three months after the end of each water year. Future AHRs will include copies of quarterly NPDES discharge monitoring reports for each NPDES monitoring site submitted to the Colorado Department of Health during the same water year. Water Rights and Alternative Water Supplies Introduction Ground water rights (water wells) within the immediate region (1 mile radius) around the New Horizon North permit area are listed in Table 2.04.7-4 and the locations are shown on Map 2.04.7-8 of Section 2.04.7 Hydrology Description. In all, 30 ground water rights have been identified in the vicinity of the New Horizon North mining areas. All monitoring wells Section 2.05.6(3) Page 7 Sept. 2015 (TR -11)