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Exhibi[ G -Water <br />Process water, including equipment wash water, dust control water, and the sand and gravel wash <br />water, will not be discharged from the site. All process water will be routed towards the <br />excavated area and retained onsite. <br />The Major Drainageway Planning South Platte River in Adams County, Colorado, Phase B <br />Report (Drainageway Plan) was prepared in 2002 for the UDFCD and local water districts (CDM <br />2002). As part of the Drainageway Plan, the east bank of the South Platte River will be stabilized <br />as shown on Exhibit G-1. This bank stabilization will be designed and constructed under the <br />direction of UDFCD and will further develop their long-term plan for the South Platte River. <br />Several BMPs will be applied to the disturbance areas to minimize erosion and sediment <br />transport, including the following: <br />• Stripping of topsoil from the floodplain area should be given first priority to prevent <br />contamination of topsoil by storm water runoff from disturbed areas. It may be necessary <br />to strip portions of the floodplain area to establish proper drainage prior to additional <br />topsoil removal. <br />• Topsoil and other stockpiled material will be stored in such a manner so as to minimize <br />wind and water erosion. The primary methods of erosion control for soil stockpiles are <br />timely revegetation and/or the use of temporary erosion control measures such as surface <br />roughening, surface mulches, berms, ditches, or small sediment traps. All soil stockpiles <br />will be constructed with 2.SH:1 V or flatter slopes, and a ring ditch will be bladed around <br />the base of each stockpile. <br />• Stockpiled topsoil will be seeded with the stabilizing revegetation mixture during the first <br />appropriate season (3 pounds of pure live seed of Western wheatgrass per 100 square <br />feet). <br />• In limited situations, topsoil and other subsoil materials may be temporarily stockpiled or <br />windrowed near active operations rather than placed in permanent stockpiles. These <br />situations would occur when the salvaged soil is needed for current reclamation, but the <br />area is not immediately ready for soil to be respread. Temporary soil stockpiles will be <br />seeded as necessary. A berm will be placed around the toe of the stockpile to contain <br />sediment produced from the stockpile. <br />Floodplain <br />In cooperation with several local water districts, UDFCD prepared the Major Drainageway <br />Planning South Platte River in Adams County, Colorado, Phase B Report (Drainageway Plan) <br />(CDM 2002). The Drainageway Plan (UDFCD 2002) designated the 100-year floodplain and <br />floodway of the South Platte River in the vicinity of the proposed mine Expansion Area. A <br />portion of the mining area property is within the 100-year floodplain of the South Platte River. <br />As part of the Drainageway Plan, the east bank of the South Platte River adjacent to Expansion <br />Area North will be stabilized as shown in Exhibit G-1. This bank stabilization will be designed <br />and constructed under the direction of UDFCD and will further develop their long-term plan for <br />the South Platte River. The armored bank will be constructed before mining commences within <br />the defined 100-year floodplain. Prior to installation of the bank stabilization, no mining activities <br />will be conducted closer than 400 feet from the top of bank of the South Platte River. Following <br />1898-Frei 112 Ezhibits_(4.20.05).doc Ci-3 <br />