2006-07-15_REVISION - M1987028 - Laserfiche WebLink

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the former mad crossing will be mazked on the mine plan map. . - 21. The Mine Plan Map Cc amended will show the location and drainage pathways of ditches constructed along in mine haulage roads. The main haulage corridor is located along the eastern side of the ore body niuning south to north along the eastern berm separating in-mice drainage from Taylor Gulch drainage. The main haulage corridor will have connecting roads for access to different operating levels of the ore body working face(s). All drainage patterns will eventually lead south and west towazds the lower pit azea. Over time and (extraction of the marble ore body), the lower pit itself will migrate northwards along the strike of the mazble bed. In-mine drainage along the haulage corridor will connect the road ditches to lower pit These haulage corridor ditches will be cut with bulldozer or motor grader in simple "v" shaped, approximately 3' deep and 6' wide along all roadways to enhance drainage flow from the roadway towards the working face and eventual diversion to the lower pit azea. The relatively shallow structures will effectively move small to moderate storm evens flows from roadway to lower pit but will likely need maintenance after a major storm events and seasonal start-up. Due to the fact that tbe ore body a~ associated woridog face(and pit construction) is directly below the highwall bench configuration, most if not all- storm related and snow melt potential not controlled by highwall beach drainage structures will flow directly into the pit development created by ore extraction. Thus, the in-mine drainage ditches will need fn handle storm or smw melt drainage from a limited azea, basically only footprint well within the production levels, stockpile areas, and actual haulage oomdor_ Atypical cross section showing in-mine road with shallow ditches on either side of roadway is included in this mailing- 22. Amended Mine Plan Map shows the waste rock berm following the Taylor Gulch rip-rap channel along most of the central and northern portions of the mine site. The berm will continue through the azea now including the FS Road 228 crossing along the lower haulage comdor ramp to the lower (main staging area). There the berm will continue along the rim of the lower staging area to insure that all run-off reaching the lower staging area will drain towards the lower pit. No vehicles will cross the berm at the existing road crossing as that road will be removed and access to the upper reaches of FS 228 will be te-located north along the berm to the northern end of the existing disturbance. Mine Plan Map Cc shows the amended contours that reflect proper drainage towards the lower pit azea. All in-mine surface drainage and sediment flow will be directed towazds the lower pit area The tce of tbe final graded waste rock dmnp will have a fors foot minimum high berm constructed along the base of the 3:l slope to contain any surface run-0ff or sediment carried from large storm events or snow melt not contained via contour furrow manipulation of the finial graded dip slope.