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exposed in the trenches was that movement of earth materials was by relatively <br />• slow creep. There was no evidence for rapid movement which would have produced <br />a chaotic distribution of rock fragments. <br />It is recognized that a slip plane(s) could occur below the levels <br />trenched; however, the geomorphology of the area of unstable ground suggests <br />slow creep instead of sudden or accelerated failure that would result in a <br />different geomorphic expression. <br />Trenches 2, 3, 6, and 7 were dug in an area defined in previous geological <br />mapping (Amuedo and Ivey, Inc., 1992, Engineering Geologic Ground Stability <br />Investigations, 005 Gulch and Vicinity, Seneca II-W Mine Area, Routt County, <br />Colorado) as unstable ground. The land surface certainly supports this <br />classification; however, the data obtained from the trenches indicates that <br />perceptible movement is not taking place at this time in the area designated <br />for the haul road crossing of the drainage. <br />• Trench A was cut in what had been mapped (Amuedo and Ivey, Inc., 1992) as <br />a fan deposit. Two interpretations of the origin of this deposit have been <br />tendered. One interpretation (Stover, April 7, 1992, Memo to Susan t4orrison re <br />Seneca II-W, permit NC-82-057, Technical Revision 16) indicates that this is a <br />landslide area, and bases this view largely on logs from drill hole DH-E as <br />prepared by Ground Engineering Consultants. The other view (Amuedo and Ivey, <br />Inc., 1992) is that this is an alluvial fan deposit that is a mixture of sandy <br />material, introduced from weathering of the nearby Twentymile Sandstone, and <br />clayey to shaly material, washed northwestward along 005 Gulch. Data from <br />Trench A did not provide a definitive resolution of these differences; however, <br />there was no evidence of landslide activity observed in the cut. As promised <br />in the meeting with MLRD staff personnel on April 9, 1992, I reviewed the <br />. aerial photography again, and on May 6-8 reviewed the area on the ground. In <br />4 <br />