2013-01-29_PERMIT FILE - C1981022A (3)

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Ste- 2.05.6 noting that the upstream and downstream segments generally have a configuration sinular to the premitrirrg cross-sections shown. Final backfilling and grading will be completed to create a stable final topography appropriate to the postmining land use. The final topographic configuration of the Elk Creek Mme area is shown by the Facilities Postmining Topography Map, (Maps 2.05-M6), and the Postminirtg Goss-Sections, (Map 2.05-M7). A significant portion of the bench fills for the Elk Creek Mme "portal bench will be removed and the excess fill material will be hauled to the Ellt Creek facilities area and placed to establish the postminirrg configuration for this area. Generally, final grading will be limited to the portal bench areas since most of the upslope slope stabilization area, used az a source for the material used to build the Ells Creek Mme portal bench, will be reclaimed immediately following completion of borrow activities, and the Elk Creek road will be retained in its constructed configuration to provide long-term access. Limited grading will be required to remove berms and culveru, regrade the light- use road and rack catch bench so they slope outward for drainage, and blend these areas with the surrounding cersain. Reclamation of the Ellt Creek Mtne facilities area will require approximately 94,500 cy of cut and 12,000 cy of fill, resulting in approximately 82,500 cy of excess cut material. Since this bench material cannot be utilized in establishment of the design postmining topography for the Elk Creek Mme facilities or replaced in its original location in a stable configuration, it will be hauled down-valley and placed in the lower Elk Creek surface facilities area az supplemental fill. Final reclamation of the Elk Creek Mme facilities area will involve grading the remaining material to blend with the surrounding terrain and promote effective drainage and rounding the edges of the remaining road. OMI will periodically inspect and visually monitor both the reestablished Elk Geek stream channel and regraded slope areas for evidence of any significant erosion or instability If significant probk:ms are detected, OMI will consult with the DMG relative to appropriate corrective meazures. If warranted, • based on site investigations and cooperative consultation, OMI will modify the channel and slope designs in the problem area(s) and make the corresponding field modifications. The pre-disturbance land use for this area was undeveloped land and historic rninittg activities. The affected lands will be reclaimed consistent with the undeveloped land use while maintaining access through the area to adjacent public lands to the north. Soil Replacement -Available soil materials will be salvaged and stockpiled during construction of the Elk Geek Mrne facilities. Available soil resources for replacement will be somewhat limited since the existing Elk Creek road was previously disturbed without recovery of soil, the upslope slope stabilization area u a natural slide where any soil is mixed into the active slide material, and soil recovery in this area maybe limited by steep slopes and associated equipment safety considerations. Available stockpiled soil material will be replaced at uniform thickness of approximately 8 inches on the original soil recovery areaz including regraded areaz, road outslopes, and the reestablished Elk Creek channel to ~*+a~~*+i>P the benefiu of soil replacement in enhancing revegetation efforts. Excess soil material recovered from the Elk Creek Mme facilities area will be used to supplement available soil resources for reclamation of the lower Elk Creek facilities area where apre-law soil replacement deficit exists. Revegetation - In accordance with an agreement with the DMG, a vegetation study was conduced for the Bear Creek and Hubbard Geek disturbance areas and adjacent undisturbed areas during the summer of 1981. The results of this study are sur*+~~>pd in Exhibit 2.04-E6, Vegetation Information, and graphically illustrated on Map 2.04-M8, Regional Vegetation. A revegetation plan, based on the study resulu, u included in the vegetation study report in Exhibit 2.05-E6. Because • other mine disturbance areas including the Elk Creek Mme area involve similar soil and vegetation types and topographic configuration and aspect, the revegetation plan haz been detemuned to be generally applicable to all mine disturbance areas. Disturbed and reclaimed areas will be prepared and reseeded consistent with the approved revegetation plan. Given that minor riparian areas are interspersed with the dominant Mountain Shmbland vegetation community in the portion of Elk PR04 2.05-64 Revised May 2001