Laserfiche WebLink
4.3 Soils <br />The upper watersheds, the present road, and the Facilities Area bench are located on <br />Carracas soils. The lower slopes below the facilities bench and road are of Nunn Loam. <br />4.4 Land Use Condition (LUC) <br />Reference is made to Paragraph 2.4. <br />4.5 Curve Number (CN) <br />4.5.1 Pre-Mined State <br />CN values of 84 over Nunn Loam and 87 over Carracas Loam are developed in Paragraph <br />2.7 for the Rangeland Reference Area (1996 Vegetation Survey). <br />CN values of 81 over Nunn Loam and 85 over Carracas Loam are developed in Paragraph <br />2.7 for the Exhibit 5 reference. <br />A CN of 87 is used for the din road area (located on Nunn Loam, a soil with a hydrologic <br />soil profile of "C", reference Table ~.3 of the SEDCAD+3 documentation). <br />4.5.2 Reclaimed State <br />Vegetation survey (1996) transects 4 and 10 of the South Slope were used to determine a <br />CN value of 84 for the upper-most watershed of the Facilities Area. The West Slope 1991 <br />section of the 1996 Vegetation Survey was used to determine a CN of 84 for the grassed <br />steep slopes above and below the facilities bench. A CN of 91 was selected for the gravel <br />road and hardstand areas (located on Carracas Loam, a soil with a hydrologic soil profile <br />of "D", Table 5.3 of the SEDCAD+3 documentation). <br />4.6 Hydrograph Response Shape <br />See Paragraph 2.5. <br />4.7 Soil Erodibility Factor (K) <br />See Paragraph 2.3. Subwatersheds above the facilities bench and the bench are on Carracas <br />Loam (K = 0.20). The slope below the facilities bench is on Nunn Loam (K=0.24). <br />Paee 14 of 34, 7 Oct 96 <br />