_GENERAL DOCUMENTS - C1981017 (222)

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feet, with the larger portion of them less than 20 feet in height. Most cut slopes range up to 602 , and a few of 402 or less. The greater portion of fill slopes are less than 20 feet high, but many are up to 40 feet or more in height. Most fills are constructed at the angle of repose (30 - 452) ; a few are placed at less than 302. only minor stability problems are found in most of the cuts. Moderate stability problems consist of sloughing, and rockfall from rock cuts. Important stability problems are large sloughs and slide areas. A major, large-scale slide area lies above the road between stations 53+00 and 57+50 in a zone of soils. The slide extends to a much greater height than the road cut, and may not be related to road construction. Road G. 19,7001 in length, with an average grade of 2.7t. Nearly half of the road length is in cut and fill construction, and approximately 25a of the road has no significant earthwork. Cuts are distributed between soil and rock. The majority of cuts are less than 40 feet in height, although a few are up to 60 feet high. Slopes of cuts are generally steep; mostly up to 602, and occasionally steeper than 60= . Cut slopes near the end of the road, at the mine bench, are essentially flat. Most fills are less than 20 feet in height, eith a few ranging to more than 40 feet high. Most fill slopes are at 30-452, the approximate angle of repose. Rare areas of fill, which are essentially flat, occur along the road. Problem Areas Encountered: High soil cut. Typical for many haul road sections. It was excavated at a steep slope, frequently exceeding 45 degrees. Its crest is somewhat steeper than the overall cut slope and may be subject to severe sloughing. Sloughed material accumulates at the cut toe. . . As the cut slope may be steep and high, the access to it is difficult or impossible. The conditions for the vegetative cover are poor. High rock cut It is either in Mancos Shale or in Mesaverde Formation. . The cut slope is typically very steep, frequently up to vertical . . . Rockfall problems are common; the debris accumulate at the cut toe. The cut slopes have not been benched and the access to the slopes is practically impossible. High, thick fill Foundations for such fills have probably not been specially prepared; vegetation or topsoil were not removed prior to fill placement. . . . The slopes of the fill are steep, close to the angle of repose. . . . Seepage of ground water along the old topographic surface cannot be excluded; it might decrease the fill stability significantly. . . . Erosion, 3