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COLORADO LEGACY LAND <br /> SCHWARTZWALDER MINE <br /> The soils and plant growth media used for reclamation are native soils from the alluvial valley excavation area. <br /> These soils are called Cryofluvents and Curecanti very stony sandy loam soils(Map Units 21 and 23 from Table <br /> 17-1 and Figure 17-1 of the Schwartzwalder Mine Environmental Protection Plan [Whetstone Associates Inc., <br /> 2016]). During the alluvial valley excavation project, clean soils shall be stockpiled and set aside to be <br /> redistributed during final reclamation. <br /> Section 7(b)(ii) of the Schwartzwalder Mine Environmental Protection Plan (Whetstone Associates Inc., 2016) <br /> provides the following description of seed and topsoil placement: <br /> "Topsoil Placement:Topsoil will be end-dumped on the crest of the slope and graded by dozers.Slopes will <br /> be graded to avoid concentrated water flow and subsequent erosion. Soil surfaces will be moderately <br /> roughened to allow the seeds to hold and some moisture to collect.Roughening can simply be the tracks <br /> of heavy equipment that has been used at the site for regrading. <br /> Seedin :Seeding will be accomplished by broadcast seeding followed by hydromulching.Hydroseeding is <br /> not recommended as it is not typically successful in an and climate. Table E-1 presents the seed mix to be <br /> used for the waste rock piles. <br /> Mulching:For 211:1V and steeper slopes, mulch is necessary to keep the seed and topsoil in place. Mulch <br /> can also provide shade to the seedlings and help the soil to retain moisture.Mulching will be accomplished <br /> by hydromulching with addition of a tackifier. Tackifier(Ecology Control MBinder) is a botanical glue <br /> made from Plantago insularis that can also be applied to the slope to prevent erosion. The hydromulch <br /> and tackifier should effectively stabilize the surface of the slope. <br /> Soil Amendments:Soil amendments may be required to improve the performance of the vegetation. This <br /> could include composted biosolids or manufactured amendments such as Biosol." <br /> EA. CONCEPTUAL CONSIDERATION <br /> This section has not changed from the 2012 Mine Plan Amendment 4. <br /> E.2. INTERCEPTION AND TREATMENT OF ALLUVIAL GROUNDWATER <br /> This section has not changed from the 2012 Mine Plan Amendment 4. <br /> E.3. ISOLATION OF RALSTON CREEK FROM SOURCES OF IMPACTS <br /> This section has not changed from the 2012 Mine Plan Amendment 4. <br /> E.4. MITIGATION PLAN FOR SOLID SOURCE TERM MATERIALS <br /> The alluvial valley excavation project began in the spring of 2018. Technical Revision 14 initial estimated <br /> 33,000 to 54,0000 cubic yards(CY)of soil were impacted by historical uranium mining practices. As of January <br /> 2020,approximately 19,500 CY of impacted soils have been excavated and disposed of onsite in the CV Glory <br /> Hole of the Schwartzwalder Mine. These materials were excavated form approximately 50% of the <br /> contaminated areas identified in Technical Revision 14,indicating that an additional (estimated) 39,000 CY of <br /> JANUARY 2021 14 AMENDMENT 5 <br />