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2.05.6(6) <br />The Bruce Park landslide is located on a southeast facing slope with <br />grades of about 15 to 20 percent dipping into the reservoir. An existing <br />road is located in the lower portions of the slide adjacent to the reservoir <br />and several ditches cross the slide area. The slide area is covered with <br />grass, weeds and bushes and is generally devoid of trees. The <br />topography is hummocky and vegetative growth indicated that water <br />ponds in several areas of the slide and/or springs may be observed during <br />spring runoff. The landslide materials consist of low to high plasticity clay. <br />Materials with high fine contents (passing No. 200 sieve), especially clay <br />fines, are at low risk for liquefaction. Based on test results, the fine <br />contents in the landslide materials are in excess of 70 percent indicating <br />low susceptibility to liquefaction. The estimated landslide volume (volume <br />of solids and volume of water) is about 1.5 to 2.0 million cubic feet. (YEH <br />Final Geotechnical Investigation and Evaluation Report Bruce Park <br />Landslide, April 5, 2006, revised November 6, 2006) <br />Groundwater within the Mesaverde formation has been found to be of low <br />quality and limited extent. See section 2.04.7 for a thorough discussion of <br />the groundwater within the permit and adjacent area. <br />Portions of Hubbard Creek road, Stevens Gulch road and Terror Creek road <br />are within the permit boundary and adjacent area. Hubbard and Terror <br />Creek roads are protected from subsidence damage by limited extraction <br />zones in the areas where serious damage could occur. The Terror Creek <br />road is considered a good wide single lane unsurfaced dirt road. The <br />Hubbard Creek road is a good single lane unsurfaced dirt road from Bowie <br />Road to about 3,500 -feet north of the Forest Service Boundary where four <br />monitoring wells are located. North of the monitoring wells the road turns <br />into a trail that is restricted to foot and horseback travel. Stevens Gulch <br />road is a two lane improved gravel surfaced road and has multiple uses. <br />Numerous jeep trails cross areas of predicted substantial subsidence. <br />However, subsidence should not result in serious damage to the roads <br />provided surface fracturing and cracking does not accompany the <br />subsidence. Any minor damage which occurred could be readily repaired <br />with a grader and/or dozer. <br />PR -14 2.05-148- 03/14 <br />