2011-08-09_REVISION - M1981185 (68)

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New Access Road Construction Work Plan Exhibit D — Attachment 1 • Wood product materials may be chipped and used for mulch; • Rock that may have rolled into the wetlands or outside of the permit boundary will be manually removed; and • Loose material and debris will be removed from slope below road by hand or by appropriate equipment approved by DRMS. Initial Grading (Sequencing) • Road will be graded to road specifications (Attachment A - Sheets C4.10 to C4.14). Road Cuts, Fills, Retaining Walls and Reclamation • Terrace deposits and colluviums are exposed in the cut slope between about Sta. 16 +00 and 19 +00 (Attachment A - Sheet C3.10). Slopes in this interval will be flatted to 1:1 using an excavator. Between 19 +00 and 21 +00, cutslopes will be excavated and flattened to achieve the desired roadway width and allowable slope requirements. Strike and dip measurements in relation to the roadway alignment indicate that the bedding is favorably oriented from a slope stability standpoint. Thus cut slopes in the Morrison formation can be steepened to a maximum slope ranging from 0.5(H):1(V) to 1:1. At the tops of the slopes where colluvium is exposed, slope inclinations will be reduced as designed. The top of slope will be rounded. Shallow drainage ditches or rock berms will be constructed at the tops of cut slopes if necessary to intercept runoff Road grades between 18 +00 to 20 +80 (Attachment A - Sheet C3.10) are approximately 12% and in one section road grades are up to 15 %. Road will be graded to allow drainage towards the inside road cut. Construction Specifications • Upper 30 inches moisture conditioned and compacted to 95% RC per ASTM D1557- 09; • New fill slopes less than 1.5 (H):1(V) will be constructed without reinforcement (retaining walls, buttress). Slopes steeper than 1.5 (H):1(V) will be constructed as outlined in the attached design; and • To the extent practicable, vegetative filters will be retained to mitigate potential erosion and sedimentation impacts. Retaining Structures • After flatting of the cutslopes has been completed and the desired roadway width established, fill material in the roadway will be removed to expose bedrock. If the bench into bedrock is of sufficient width to reconstruct the fill at an inclination no steeper than 1.5 (H):1(V), the roadway subgrade will be reestablished so that roadway grades are not steeper than 15 percent. Fill will be free of organic materials and rocks Wildcat Mining Corporation May Day Idaho Mine Complex — 112d Permit Application Revised August, 2011 Exhibit D — Attachment 1 Page 8 of 15