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neither review could I find evidence of present or past instability. With the <br />• evidence now available there does not appear to be cause for concern that the <br />haul road alignment and the right abutment of the sedimentation pond embankment <br />impinge on this area since the design of both features will be coordinated. <br />The following are my opinions based on geological mapping done in October <br />1991, and on logging the trenches on May 6-8. <br />1. The general area between Sta. 53+70 and Sta. 63+85 where the haul road <br />is planned to cross the natural drainage of 005 Gulch is mapped as <br />unstable ground, but no evidence of recent movement was found in the <br />trenches dug. <br />2. Slip planes, and any evidence of recent movement of surface and <br />near-surface material were not found in any of the six trenches dug. <br />• 3. Definitive correlations of geologic features was not made between <br />trenches. <br />4. A consideration of materials exposed in the trenches and the <br />morphology of the land surface lead to the conclusion that movement of <br />unstable materials has been by slow creep, rather than by rapid <br />failure. <br />5. The coordinated design of the haul road and the sedimentation pond <br />embankment should obviate any problems where the two features impinge <br />on each other. Problems, other than some settlement, are not <br />anticipated. <br />6. The key to maintaining the level of stability presently found in the <br />area examined in Trenches 1, 2, 3, 6, and 7, is to provide for <br />adequate drainage of 005 Gulch with one or possibly two culverts. <br />• <br />5 <br />