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o Rocky Mountain Penstemon(0.76 lbs/ac) <br /> o Big Bluegrass(0.50 lbs/ac) <br /> o Spike Trisetum(0.63 lbs/ac) <br /> o Junegrass (0.23 lbs/ac) <br /> The application to the slope will occur in the following steps: <br /> 1. Step 1: Roughen and furrow smooth surfaces of the slope using hand tools(photos 2-3). <br /> 2. Step 2: Combine items 1-5 with the prescribed volume of water in a hydroseeding tank;blend <br /> with approximately half of the prescribed seed mix; and spray onto the slope at the prescribed <br /> application rate(photos 4-6). Items 1-5 are a combination of fertilizer, growth media and topsoil <br /> alternatives selected by Triton Environmental,DOWL Engineering,and Clarke&Co., Inc. <br /> (collectively"contractors") for the specific slope,high pH and low organic content of the modern <br /> tailings. <br /> 3. Step 3: Blend item 6, a high-performance erosion control mulch product,with the remaining seed <br /> mix and prescribed amount of water in a hydroseeding tank, and spray on the slope(photos 7-8) <br /> after the application of items 1-5. The mulch is designed to provide enhanced erosion control by <br /> interlocking the tailings substrate and previously applied growth media, and was also specifically <br /> selected for the modern tailings by the contractors. <br /> Schedule and Monitoring <br /> On October 4-5, Caldera completed a 1-acre test plot on the steepest aspect of the modern tailings by <br /> implementing the methods described herein(photos 2-16). The purpose of completing the test plot was to <br /> evaluate costs and the short-term and long-term efficacy of the application on the steepest slope. Based <br /> on the short-term results,a similar application was used on October 26 at select areas of the historic <br /> tailings(photo 17). <br /> Caldera is required by EPA to closely monitor the long-term efficacy of the application. Since vegetation <br /> was essentially non-existent prior to the application,the proposed extent of monitoring will be seasonal <br /> photo documentation at the same locations as the photos herein. <br /> pending monitoring of the test plot and the progress of the adjacent Phase 1 work,the remainder of the <br /> slope treatment will be applied between October 2018 and October 2020. Adjustments to the seasonal <br /> timing and additives of the application may be necessary based on monitoring. <br /> Water Resources <br /> Caldera will use its water rights at and near the mine to supply water for the proposed work. <br /> No negative impacts are anticipated to occur to surface or groundwater resources during or after the <br /> application. The purpose of establishing vegetation is to protect water resources by preventing erosion of <br /> tailings. <br /> Access Routes <br /> Access to the top of the slope will be from the overland route that exists on the flattop surface of the <br /> tailings accessed from County Road 361/26B. Access to the bottom of the slope will be from hand <br /> carried spray tubes (photo 8)that connect to the hydraulic seeding tank at the top of the slope. <br /> Page 3 of 4 <br />