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Revegetation Assessment <br /> Guanella Reservoir <br /> Clear Creek County,Colorado <br /> The species seeded in 2013 from the Reclamation Permit Seed Mix were analyzed to ascertain if they <br /> were compatible with the soil and other conditions within the project area, as shown in Table 2. This <br /> seed mix consists entirely of introduced species, which are not as well adapted to local conditions as <br /> native species. Additionally,at least two of the species are intolerant or moderately intolerant of saline <br /> conditions. The two fescue species were not observed in the reclaimed Phase II area (September 2017 <br /> Inspection Report) and are more typically used in lawn or golf courses and not revegetation applications. <br /> Table 2. Reclamation permit seed mix tolerances. <br /> he used(n/ Rawl oewih- <br /> canaroe Ugme scilleawkNWIle Hoove(M pH RMV Alkaunity/Sak Tolerance <br /> (inches) <br /> Ephraim Crested Wheatgrass Agropyron cnstatum I .0-8.2 Medium,under saline conditions,18 <br /> vigor/production are reduced <br /> Dwarf Perennial Ryegrass Lobum perenne I 0-8.0 High 10 <br /> SR3200 Blue Fescue Festuco glauca I Not rated* Not rated* Not rated* <br /> Reubens Canada Bluegrass Poo compreso I .0-7.0 No 10 <br /> Chewings Fescue Festuco glauca Not rated* Not rated* Not rated* Not rated* <br /> *Tolerance data is not available for either fescue. <br /> Source:U.S.Department of Agriculture(USDA),Natural Resource Conservation Service(NRCS)Plant Database 2018. <br /> Recommended Revegetation Plan Revisions <br /> Soil Recommendations <br /> To remove the salts, the CSU Soil Testing Lab (Appendix A) recommends adding gypsum and water to <br /> leach the gypsum through the soil and remove the sodium (salts)from the root zones. However, based <br /> on ERO'S assessment of the project area,there is concern that the salts would continue to leach up and <br /> prevent sufficient vegetation from growing in the project area. <br /> To prevent salts from leaching to the surface, ERO recommends placing a layer of different textured soil <br /> (such as clay)to create a barrier between the topsoil/subsoils and the existing ground. To determine <br /> which type of layer to use,a soil pit about 3 feet deep should be dug in the spring when the ground is <br /> not frozen. The texture of each layer of soil from the surface to the bottom of the 3-foot pit would be <br /> determined. Based on this testing, a plan describing the barrier would be developed and submitted to <br /> DRMS. <br /> This plan would include excavating the project area about 2.5 feet and removing the excavated soil to a <br /> designated location. The excavated area would extend 1 foot above the salt-crusted project area. Then <br /> a barrier of approximately 6 inches would be placed at the bottom of the project area extending to the <br /> 4 <br /> =R0 Resources Coraorat on <br />