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shown on the figure, Ditch H bisects the area. Berms were installed on each side of Ditch H to <br />keep disturbed area run -off out of the ditches. In response to NOV CV- 2007 -003 two additional <br />silt fence segments were installed along each of the channel berms on the east and west sides <br />of Channel "H" berm. Additionally, a berm break and water bar were installed to direct flow from <br />an ephemeral channel into Channel "H ". <br />The mine bench area was reclaimed in 2007 and the vegetation has thrived. A sediment <br />loss comparison has been made that shows run -off from the vegetated mine bench area will <br />contribute fewer suspended solids to streamflow or run -off outside the permit area than <br />untreated drainage from the natural surrounding premining area. Therefore the silt fences can <br />be removed. The sediment loss comparison is located in Appendix M(viii) beginning on page <br />M(viii) -4. <br />Waste Rock Disposal Area <br />See section 2.2.5 Waste Rock Disposal Site. <br />2.3.5 Erosion Control Considerations <br />2.3.5.1 Existing Erosion <br />Existing soil erosion rates in areas to be affected by the mine operation vary with the land <br />form, soil characteristics and vegetation cover. Erosion potential exists for three land forms with <br />the area to be affected: <br />Valley filling fan and side slope deposits <br />Steep side slopes <br />Valley flood plains <br />Soil loss rates were not calculated for each land form type; however, the presence of rills <br />and gullies in the area substantiates the fact that a significant amount of soil loss is realized <br />annually from the undisturbed slopes. Soil loss in the flood plain is negligible except for the <br />cutting of the unvegetated stream banks that continue to erode during periods of stream flow. <br />2.4 TOPSOIL MANAGEMENT <br />The primary goal of this topsoil management program is to realize effective conservation <br />and utilization of plant growth medium for the postmining land use. No topsoil was salvaged <br />prior to bench excavation or road construction. In accordance with criteria existing at the time of <br />disturbance, no salvageable topsoil existed at the bench area and along the excavated portion <br />of the road route, especially on steeper slopes. Portions of the route did exhibit some week and <br />grass growth. A great portion of the road, located within an area exhibiting marginal topsoil, was <br />established over the existing road on the canyon floor. <br />All suitable topsoil materials from future areas to be affected will be removed as a <br />separate operation and stockpiled prior to effecting a disturbance, as discussed in Section 2.4.2. <br />Topsoil will be stockpiled in the vicinity of the disturbance, mulched and seeded to wheat <br />grasses in order to minimize erosion, and adequately marked to preclude disturbance prior to <br />reclamation, see Section 2.2.6 and 3.2.3. <br />TR -25 2 -27 05/14 <br />