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reclaimed. As part of the earthwork for the creation. of the wetland bank. this lake will be <br />filled. The adjacent riverbanks show some invasive species and some effect due to <br />previous impacts. Improvement of the river corridor will. be included in the bank design. <br />Water tests were performed on the nearby irrigation ditch, the river, and the two existing <br />ponds. The water tests were to provide a baseline survey of the water qualify. Also the <br />water was tested for dissolved. selenium. due to the increased interest of selenium on the <br />Western Slope. Little to no selenium was found in the samples. However if selenium or <br />other dissolved metals are later found in irrigation water or ground water, these waters <br />may be diverted into the bank. to help remove contamination. <br />3.Q Proposed Wetland dank ~~sggn <br />This site will. be completed in one construction phase. The construction will take place in <br />four stages. The topsoil and overburden will be removed and stockpiled outside t?~e <br />wetland bank area. Once the stripping is completed the gravel will be regraded or <br />removed from the site in order to lower the elevation of the site. This will allow <br />subirrigation of the plants. After the earth moving is completed the topsoil and <br />overburden. will. be replaced. Various wetland and upland buffer plant species will be <br />introduced to the site. Map 3 shows the planned design of th.e wetland. bank. <br />3.1 Topsoil and Overburden dandling <br />Topsoil consists of weakly developed soils derived from recent sandy and gravelly <br />a luvium. The predominant soil, Nicolaudette loam, has 2 to 3 feet of loam and sandy <br />Loam over l,~ravelly substrata. It has moderate permeability and low available water <br />capacity. Parallel to the Uncompahgre River along the floodplain are iuldifferentiated <br />Fluvents and Fluvaquents, consisting mainly of recently deposited gravel bars. In the <br />natural state, the layers below the topsoil are sand and sandy loam parent material and not <br />subsoil per se. In mining terns, the sand and sandy loam would be considered <br />overburden. <br />Topsoil anal overburden will be stripped pi7or to establishment of the final site grade. <br />Approximately 0.5' of topsoil. exists across the site. Portions of the site have already <br />been stripped of topsoil for the mining operation. The overburden will then be stripped <br />and stockpiled separately from the topsoil The approximate thickness of the overburden <br />is l.S'. There is not an easily seen division between the topsoil and overburden. <br />However, the overburden ,has noticeably i~nore cobbles than the topsoil. Both maybe <br />used for growth mediiun. <br />3.2 l~arth work <br />After topsoil and. overburden has been stripped the gravel will be removed and. re-graded <br />to form the topography as shown in Map 2 included in Appendix C. The ground will be <br />regraded to form a series of swales. These swales will direct the available irrigation <br />water along the bottom of the area. "The northern pond will remain with a small buffer <br />between the swale section. The southern pit will be filled. Filling the pond- wilt. provide <br />additional wetland acreage as well as reduce the evaporative losses o~Ethe site. Some <br />material will. need to be taken. offsite in order to achieve the desired grade. The .removal <br />