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Revegetation Assessment-Revised <br /> Guanella Reservoir <br /> Clear Creek County, Colorado <br /> were frozen. The soil samples were submitted to the CSU Soil Testing Lab for routine sampling(pH, <br /> salts, organic matter, NO3, P, K, Zn, Fe, Cu, Mn, B lime, and texture estimates) plus Sodium Evaluation <br /> (SAR). <br /> Because the soils were partially frozen during the March 2018 site visit and additional information was <br /> deemed beneficial, another set of soil samples was taken on May 11, 2018 (May 2018 site visit) after the <br /> ground had thawed. The methodology used during the May 2018 site visit differed from the March <br /> 2018 site visit in that a deep soil pit was dug to approximately 4 feet at two sample points. At S1 (May <br /> 11,2018), samples were taken in each of the three layers present in the soil column (S1a, S1b, and S1c, <br /> Table 2). At S2 (May 11, 2018),the top layer was not sampled because it was similar to the top layer in <br /> S1 (S1a)and only the subsurface layer was sampled. <br /> Table 2. May 2018 soil sample descriptions. <br /> Sample Description Depth of Soil Layer Soil Texture(from lab <br /> results) <br /> Sia Topsoil 0 to 4 inches* Sandy clay loam <br /> Sib Sandy subsoil,with inclusions such as larger 4 to 27 inches Sandy clay loam <br /> cobbles and some asphalt. <br /> Sic Gravelly subsoil with cobbles(taken out of Below 27 inches Sandy loam <br /> sample submitted to lab);sample taken at 37 <br /> inches. <br /> S2 Topsoil 0 to 10 inches(no sample taken because Loamy sand <br /> similar to S1a);subsoil below 10 inches—may be <br /> native soil;sample taken at about 28 inches. <br /> * The soil depths were measured at one location only. The average topsoil depth within the project <br /> area was about 7 inches. <br /> Results <br /> The results for the soil sampling from the March 2018 site visit show that the soils in the project area <br /> (S2) are very high in salts,and high in sodium (alkaline), which would severely reduce plant growth <br /> (Appendix A—March 13, 2018 Agricultural Test Report). In contrast, the pH is suitable for plant growth, <br /> and the organic matter amount is more than 2 percent (2.6 percent), which is suitable for growing <br /> native vegetation (Munshower 1993). Where vegetation is growing (S1),the pH and salt levels in the <br /> soil are acceptable, although the pH at 8.1 is basic and may be unsuitable for some plant species. <br /> During the May 2018 site visit,the soils within both pits were dry down to 4 feet below the surface with <br /> no evidence of saturated soils. Since the samples were taken in May when the water table is typically <br /> higher,the unsaturated soils indicated that a high water table is usually not present. However, because <br /> ERO Project#7158 4 <br /> ERO Resources Corporation <br />