_GENERAL DOCUMENTS - C1981017 (232)

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excavation and armoring of the channel will be accomplished. A diversion ditch will be constructed on the Old Refuse Pile for the purpose of routing surface flows from near the top of the facility to the base of the pile. This will eliminate the need for the ponds (upon approval of the Colorado Department of Public Health and Environment) and the resultant cascading water which flows from upper pond outflow down the north side of the pile toward Dutch Creek. The channel would be trapezoidal in shape, and would generally follow the access road except as needed to maintain a gentle grade. The channel would be topsoiled and lined to promote growth of energy dissipating grasses. Two shorter and smaller feeder ditches would also be constructed on the Old Refuse Pile in order to accommodate the drainage from all portions of the facility. Earth Work, Grading Grading will be accomplished in numerous portions of the Project Area. The belt line transfer pad located north of Coal Creek will be graded to approximate the original topography of the area. The portions of the yard area (ie: entire Wash Plant vicinity from western most Coal Creek culvert, east to the Dutch Creek Flume) not affected by the Dutch Creek Diversion project will be rough graded. Grading will accomplish filling of existing drainage structures, fill the drainage sump located to the north east of the old office building, and to create a swale at the previous location of the Dutch Creek Flume. A hummocky topography will be created to facilitate revegetation success and erosion control. At the Old Coal Storage Area, located immediately north of the second switchback of Road A, the remnant coal will be pushed west to base of the west hill. Grading of the pad and surrounding north and west slopes to achieve appropriate landform and drainage patterns, will occur. Grade bench uphill (west) of pad to accomplish drainage to east, round out east and north pad slopes; rough grade entire area. Grade the toe of the slope south and south west of preparation plan to accomplish a land form consistent with that created by the concrete disposal and burial at the base of this slope. In addition, miscellaneous materials will be buried and drainages pattern will be established. Earth Work, Rip The entire project area will be ripped to an eighteen inch depth on no greater than thirty inch centers to promote revegetation success. Topsoil Application The entire Project Area will be topsoiled with one half foot of topsoil derived from the lower Sutey Topsoil stockpile. Revegetation Specifications will be nearly identical to other Invitations and Bid documents, however drill seeding of flatter areas will be allowed. Seeding in mid- to late September will be required. It is estimated that approximately 25 acres will be disturbed, and thus require revegetation. 27